## Technology related projects

 Techdemo, 2009. 2012 3D printing, 2012 Graph project, 2011 Structure from Motion, 2009,2007 Geodesics, 2009,2008 Benefits/Risks of Tech in Classroom [PDF], 2007 Flash PITF, 2004 Sofia AI project 2003/2004 CCP 2001 I,II

## Technology notes 2017-2020, 2007-2010, 2011-2015, 2016, Now

17-07-2020: Got my new thinkmate workstation at home. My trusty older workstation is already 7 years old and still fit, filled with a half a dozen harddrives. But it would slow down sometimes heavily when doing harder mathematica computations or render non-smooth google earth flight simular pictures while simultaneously screen recording. An other reason is that now, while unable to access my office machine, I need a redundant set-up, just in case something would happen. We have no air conditioning at home for example and in the past, it was always during hot summers that a computer would die. I simply could not afford having even a few days without a computer. I had a budge limit of 2000 dollars and wanted a Ryzen (also because these AMD processor types somehow evoke a bit of new excitement). Also, just because of reliability and because the machines are on 24/7 all year, I don't want to high power consumption and went with a Ryzen 5. I expect only a performance gain of a factor 2 over my old machine but I also got 64 gig of RAM, which is 4 times more than before (I would go here definitely for 256 Gig if I had the cash). Also the graphics card is not that high end: NVIDIA Quadro P620. I like really stable and solid power supplies because this also prolongs the life of the PC. I have a AX1200i and the modular cable set-up really makes the machine clean. The Mid Tower Chassis is wisper quite. One does not hear the PC (that is one of the reasons to go with Thinkmate). I have built a PCs from scratch (which is a bit cheaper) but it had not lived long. This is my sixth thinkmate since almost 20 years now, 4 still run nicely, two older ones retired while still operational. When I got the workstation, I first thought that they forgot to put the graphics card (which is much smaller than my old monster) and the solid state drive (250GB crucial MX500 M2) which contains linux Ubuntu 20.04. (I prefer if the vendor already puts an OS on the machine as this makes sure that everything works). Of course, with thinkmate, you do not have to buy a windows OS. By the way, here is the workstation type. My dream configuration there would probably have cost twice as much (I had to stay below 2000). Here is a photo (click for a larger version
07-06-2020: Had broken my ipad and needed to fix it. Got a fixing kit from amazon but opening that screen and scraping off the glue is quite tough. Took me a while and of course, I damaged the button cable which had been glued into the screen and would have had to be removed very carefully. Got therefore also a new button. The repair finally worked but it is not for the faint-hearted. Some of these tiny screws are as small as fleas and one has to attach the tiny connectors to the screen while the touch screen pad and the glass screen parts are both in impossible positions. It took me in total several hours. I do not know how repair shops can do that much more effectively.
16-05-2020: A nice article in the register about Algol 60. I never programmed with Algol, but it describes also a bit how programming worked early on. Accidentally, in our first numercial analysis and programming course, we had to program an advanced ODE solver and submit the program to a mainframe (using punch cards). Yes, there were already macintoshs around, but somehow, these old assignments were still given at ETH (a time when the CS department was still together with the math department, it split while I was there). The story of punch cards makes one appreciate modern programming. You had to write the program, produce the punch card, then submit the job and then, after a while get back the result (which when it had mistakes, required to rewrite a new punch card and try again). This is a bit similar than writing text with a type writer. I wrote a research monograph as a highschool student using an IBM selective type writer, where usually, after mistyping a letter, one had to start over or then go over the old spot and overwrite it with a special tipex tape. This slow process forced to work more carefully.
12-05-2020: It is good, my office machine is on auto reboot. I can not go there and if there is a power outrage, like last weekend, the machine has to come up itself. So far, this works well. The machine still computes Hardy and Littlewood primes there. I upgrade my homeoffice machine from Ubuntu 19.10 to Ubuntu 20.4.
25-04-2020: Some short video swoop in our home office (video produced for a department wine and cheese party).
13-04-2020: Our FIOS box got fried during a power outage (relatively trivial thing: the power supply is dead). In a time, where everything is done over the internet, also teaching, this is devastating. Fortunately, there is still the phone which allows to access email and allows also to buy more wireless data plans. It will be interesting to see whether the phone connection will work for teaching online.
23-03-2020: Today is the first day of class online. Some pictures illustrating this, in particular, the teaching set-up. Having taught already a course online before, one of the challenges is the surge of information which everybody distributed. There are many ways to teach remotely, many techniques and teaching is very individual. One thing might work for one person, an other might work better for an other. Yes, websites like this are helpful but the amount of information distributed in the last week is even overwhelming for me who is almost constantly working with technology. I'm a bit anxious to see whether zoom lectures will work. It is actually amazing how well the internet infrastructure holds so far. [Update March 25. Things work surprisingly well so far.]
13-03-2020: Covid19 has forced to use more online learning as students were sent home for the rest of the semester. This will be challenging but also lead to insights about online learning. We will be learning also more about what technology works. Will the sudden increase of online resources work without glitches. Doing lots of video online needs bandwidth and also computer power. When I taught MathE320 online, Zoom was ok but needed resources. Here was my Zoom setup: [JPG panorama picture] with two laptops as one laptop alone would freeze up with both keynote and zoom running at the same time. An external monitor allowed to see the class better. It is very likely that with the sudden unexpected increase of online resources, challenges will occur.
21-12-2019: The web more and more becomes a nagging place. When visiting sites in Europe, one gets almost uniformly greeted with a "we use cookies and other technolgies" dialog. The user has first to click away that dialog. Additionally, news pages push users to register. Obviously this is not going so well (who wants to be tracked when reading) so that currently they give away prizes for signing up. Also in the US, newsportals like the new york times or Washington post put more and more content behind paywalls. It has the effect that websites of cable news like CNN become again more attractive. Maybe one has to look at other formats to support journalism. In Switzerland, there are still publicly funded structures which work. And in the US, there is still NPR but this relies on support from the public.
19-12-2019: It had not been my call, but the old department pages are now on legacy mode. The old page had been written by myself in Perl, and many things were automatically done by scripts. Automation is easy to implement with static pages. (An external company has worked on the new wordpress page for one and a half years. I had not been consulted during the transition nor do I yet have access. Things obviously have still to be smoothed out.) The now called legacy page" had been programmed in a few weeks while also teaching. Wordpress is a decent choice. I use it for my own blog but editing a CMS takes longer than a flat unix page like course websites, or rhetorik and rheinfall pages (for both of which I'm the editor since 23 years). One can get used to CMS, where content can be authored by many but they also tend to look rather plain. The hosting of CMS's must be done professionally. The old department site has been hacked when we had implemented CMSs (we had various internal wikis or the CMSA page which had been hosted at the math department first. It is always sad to see content disappear because the web should be a library, containing documents to which one can refer to. Taking down content destroys heritage and culture. Now, things like can not be linked to for some time. But things will pick up.
15-12-2019: A test with TikTok. Looks as if this has a lot of potential also for teaching but the portal is for now mostly used for dance clips. I had experimented with Vine" during 2013-2014 but that platform died. Lets see how long this service will work. The live cycles of Social networking sites appears to become shorter and shorter. I had liked Linkedin once, but now one can not even see the basic profiles any more without logging in. Microsoft currently chokes the platform to death. It is always the same: the founders have good intentions and leave things open until a critical mass of users has been achieved, then they milk it and strangle the service to death. Today, there was some discussion on Slashdot whether youtube should be subscription based. I would not be surprised if this would happen in the future. It of course would lead to a painful death of the platform. Lets see how long TikTok will make it. I like it how simple it is to use.
25-11-2019: The apple music store redesign makes search so difficult. The first thing you want in a store is to have a search box which allows to find and buy songs. I just watched the movie "Point of no return" which has a great sound track of Hans Zimmer. I like the movie and I like the sound track (there are various movies of that theme, (a recent one is Anna). Searching for the Zimmer soundtrack on the itunes store always refereed to apple music. WTF. I want to buy the song and not rent nor stream it. No reference to the point where one can buy it. How could I eventually find it? By first downloading the song from youtube, load a converted m4a version into itunes and then go from my own music library and search for it in the iTunes store. So, I was eventually able to buy it. I'm sure they lose millions of revenue by just have no search box (the search box on the left does not find shit in the store). It is funny that search" appears to be so difficult. Google of course has figured it out and we are all spoiled. Spotlight on Apple, the Harvard course catalog are examples, where search are disfunctional. Fortunately, there are hacks around it: in unix (and apple is a unix box too thank good), one can search things nicely with find" (a good old unix tool which is much better than spotlight. Spotlight finds thousand entries but which are mostly irrelevant). An other example is the course catalog at Harvard can only be searched by just looking at the PDF, OCR it and then search the text. I do not find my own math course on the Harvard course catalog. Sometimes, the simplest solutions are the best. A simple grep search. If that is too difficult, maybe have just let the search engines to the job. That works on Amazon for example (also there the internal search is riddled with infused bias).
04-11-2019: The dock disappeared on my laptop running Catalina OS. Others have that issue too. Following advise, fiddled for 5 minutes with the dock configuration tool or defaults delete com.apple.doc; killall Dock; with no solution. Then tried this. After some random size changes, it appeared back. Later the day, it disappeared again and worse, boot-up and apps take ages, network problems. Currently reinstall Catalina from the recovery mode. [Update: this did not work. In this case, I make a radical tabula rasa" move: rm -rf ~/Library/* which worked but requires to reconfigure various things.
02-11-2010: Now, also firefox by default saves images in webp format. This should be an obvious menu entry to change back. Now one has to type about:config in the address bar Search for webp and set the image.webp.enabled" value to false" by just double clicking the line. But there are are already websites which then do not display image files if image.webp.enabled is false. There are really moments, I hate developers changing long established settings just to push the new file format. In the long term, it might well be that webp will take over and replace png, gif and jpg formats, but it is not yet a format which is widely processable by image. Gimp opens them, but imagemagick does not convert them yet (ImageMagick 6.9.10-14 gives an error).
24-10-2019: Changed now also a second laptop to catalina (keeping an old version is in the long term never sustainable). There are more annoying changes. Iphotos now keeps the photos organized differently. No more in Masters, but in a folder originals, where annoyingly the photos are split up into lots of directories. The file extension is no more .JPG but .jpeg and transferring the photos from the phone does not delete the photos even if requested. The iphotos app is a total disaster. I keep my photos nicely stored in a plain folder in linux not depending on the whims and taste of app UI designers. But still, it is tough to get the bare jpegs from the app. First of all, the file names are cryptic 40 letter long password type files. That is no problem as this can be reordered in unix. The biggest problem is that when copying the files over, the stack of pictures is neatly shuffled. Pictures which were taken a few seconds after other are now equipped with a random name. Bravo apple. Maybe it was done to lock users to the platform, who knows, but iphoto has finally become the worst app. Fortunately, there is still the ImageCapture app which preserves the file names.
22-10-2019: Ron Rivest talks at Harvard on Voting security. Simple take away: Use paper ballots. KISS (Keep it simple), voting is also a matter of trust (the public needs to get insight that it works).
21-10-2019: Google pushes grasshopper a coding app which works within the browser. It is actually quite well done. (I only tested out the fundamentals 1 until the end). The problem with these apps (like DuoLingo for languages) can be that the app changes in time. In duo lingo for example, I could get for a long time very reasonable assignments and make good progress and then reach a very steep hill, losing all points with stupid typos or with unclear assignments, or then the goal post has moved adding much more assignments. The grasshopper app so far has been reasonable so far with not frustrating the user with undoable assignments. This is essential for teaching tools which do not come with a teacher who can clarify.
20-10-2019: The new apple music app replacing itunes needs some time to get used to. The trend continues to constrain the user and lock it to a specific layout. It wastes my real estate with more boundary and with art work I can not get rid of. It used to be that one could change the divider between two logical units in an app. Seems not be possible any more. The middle column can not be moved away. There is no divider where one can make it smaller. The ordering of the songs has changed, does not honor what I had configured before. Almost no choice in configuring the geometry. Now, I see maybe a list of 10 songs and the entire real estate is used up. UI designers are just so full of it. Sorry.
15-10-2019: Python renders different results on different platforms. This is not that surprising, one would expect even different result with different CPU's (or GPU's if they are involved) when dealing with floating point arithmetic. But in that case, the scripts produced different file name lists. The reason was that some Python routine called some sort of system IO. That can happen in any programming language which allows to call system parts. I have used countless many times "system(...)" from C programs for example. In Mathematica one can call programs with "Run". Now, the result of that system call of course can depend on the OS. [By the way, when I arrived here in 2000, I had installed a Mathematica backend integration routine which allowed to evaluate integrals by just calling an URL (a very primitive wolfram alpha...). This little CGi script went on on 5/20/2000, right after I arrived in May 2000, where my office machines were still directly on the web. Of course, this would be forbidding now (CGI in general is out and my current machines are each behind two firewalls and inaccessible from outside). But already then, the CGI script had to parse things and add a CPU and memory limit in order to protect the machine. Mathematica so far produces mostly identical result on different CPU's but we have seen examples of results obtained by solving PDE's where the result depends on the OS. ]
06-10-2019: Mac OS Catalina is a bit of a pickle. I do not install it for most machines yet for the simple reason that it breaks many of the 32 bit programs I still use. An example is Acrobat Pro" which is decent for compressing PDFs really nicely and also OCR's well in various languages. Open source (tesseract) does not cut this yet and having tried a dozen other tools, they still suck, also the Quartz filter in Preview is terrible (either they do not compress well or then they compress so much that things become blurry, Acrobat Pro had a sweet spot there). There is also Quicktime 7, which is a nice little piece of software. Just open a movie, cut and paste some parts, extract pictures, combine pictures to a movie etc. Yes, one can do things differently, but open source video is still a bit shaky (a script which combines pictures to a movie might work now, but not in 5 years, because some developer decides that ffmpeg does not cut it any more because avconv is in) or then produces massive files. So, for me, a move to Catalina remove some incentives to use the Mac for, which is to be able to do things which one can not do under linux yet. Removing 32 bit compatibility was a mistake. Did apple not learn from Windows compatibility break disasters? [Update of October 12: I tried a Catalina update on a non-production laptop: The anyvideoconverter" works. Unix stuff required to reinstall macport. The Scan snap software does not have a Catalina compatible update yet. The OS bitches also about zsh even after telling chsh -s /bin/bash' (an entry "export BASH_SILENCE_DEPRECATION_WARNING=1" in .bash_profile and .bashrc helps to shut this nag. An OS should never nag!!!! ) Also, what is this forced change of shell thing? I want bash. I'm not a zsh man, god damn it, I'm a dapper bash man!. Mcports failed to install texlive" even after removing /opt/local completely and reinstalling macports from scratch. Reinstalling MacTeX did the job and latex works. Now it is not that bad any more: scan snap and acrobat are the only remaining problems for me. I can live without quicktime & (as things can be done with Final cut and basic trimming with the new quicktime). Scan snap will be ported in a few months. For acrobat, I need to look for an alternative PDF compression and OCR. I don't do subscription software, I'm a dapper standalone software man! ] P.S. A strange thing in Catalina: in a terminal, the programs of /Applications/Utility do not show. They show in the finder. Very weird: See the screenshot. Update October 16: A fresh download of Scan snap worked now with Catalina. I also bought the app PDF-Compress for 10 bucks. It comes close to Acrobat Pro, when compressing to 150 DPI and produces only 20 percent larger files than Acrobat Pro. Does not do OCR although, just compress.
29-09-2019: No surprise there voting machines are still vulnerable. Ethical hackers tested the machines and were able to get into EVERY machine they got their hands on. Quote by Sen Ron Wyden: "it is basically a piece of cake for a relatively savvy hacker to compromise an election and alter votes."
26-09-2019: Some headlines about computer aided proof verification. An example is the formal proof management system Coq. Of course, many proofs contain mistakes, history has illustrated this. It is even possible that entire axiom systems are inconsistent. Mathematics has proven to be quite resilient also to severe foundational crisis. Proofs with gaps most of the time can be repaired. Some of the nicest mathematical results were first proven with mistakes (Euler gem, fundamental theorem of calculus, fundamental theorem of algebra). There had been gaps in the proof of the classification of finite simple groups. But we also become more picky. Many fundamental papers from 100 years ago would today never be accepted. They would be considered "too short" or "insufficient references", or "too long". The abstract of ITP 2019 which was headlined is What makes a Mathematician Tick?. From the technological point of view, automatic proof verification is a front runner to automatic proof generation. The last step will be automatic theorem searching. Well, in the end, we can just sit at the beach and read automatically written, refereed and read papers. Brave new world.
25-09-2019: Just read in the register about more "System D" take overs. The title in the register article is as always a pun, the content however looks as if linux is heading for serious trouble, if systemd changes the way user directories are maintained. " Lennart Poettering told the crowds at the All Systems Go Linux user-space event in Berlin he intends to reinvent home directories to fix issues with the current model" and "His solution is that the user must already be logged in, for SSH to work. A person at the session asked what should be done by a university student, for example, who wanted to log in to a Linux machine that was rebooted overnight from 200 miles away. The answer: "If you really want that this system can come up on its own, don't use this stuff. This is about security." Well, I have a better solution and this is really secure: just don't do stuff any more with computers". In the same way as just don't leave the house any more" to solve the problem of having an accident. SystemD managed home folders could make sense however in some restricted environments, where users" are mostly consumers" who don't do stuff and where it does not matter if they are locked out after a system reboot.
01-9-2019: The trend to hide things continues. I just updated firefox in linux. Now also here, the menu bar is gone. I like the menu bar. How do you get the menu bar back? It is a bit of a catch 22! The Support page tells to go View->Toolbars->Menubar. However, the View part is only visible in the menu bar and not in the Hamburger menu. One need temporarily to use F10 to get the menu back in order to enable the menu again.
11-8-2019: A little drone flight near the science center is not only technologically exciting. We have come a long way from da Vinci's first grasp of helicopter flight to modern drones which work technologically quite well today. [We are 4 years past 2015, the year appearing in the back to the future' scene with the flying cars, but we still have no cars for the masses, for obvious reasons: noise, safety, environment] Technology depends on a lot of things it is not only what can be done, but also what is allowed to be done. In the case of the drones, there are already quite severe restrictions. A drone can not fly too high and modern drones know their limitations depending on where they are in order not to violate some airspace. Also, responsibility requires to be not too close to people. Additionally, one has to be careful not to damage anything. A responsible flight can therefore not be too spectacular.
9-8-2019: The register reports as one of the few about a talk of Bruce Schneier at the Black Hat Def Con conference. The upshot is simple and given in the title of that article: "You can easily secure America's e-voting systems tomorrow. Use paper". And a quote which seems to be not only true but an understatement: "The technical knowledge of most congresscritters is sadly lacking".
25-7-2019: Having used SSD's for the OS for a long time already (my last linux machine moved over the OS to SSD in 2010), there is still a lot of moving platters as the larger partitions of are regular harddrives. SSD has been too expensive for 3-4 TB drives. They soon become (almost) affordable. I could not resist to buy a SAMSUNG 860 (4TB) in order to move /home finally also on SSD. It is still a bit crazy with 550 bucks but it is one of the rare cases, where one can again become excited about PC technology (many other things become just marginal updates, the times when every new machine was a mile stone are gone, I remember getting the NeXT or the first apple laptop or my own Sun workstation). I will soon see whether one can feel the difference, it takes a while to sync over the /home. Still, the other 5 HDs (all 4 TB) in my machine are still moving. I can not wait until everything is SSD. It will use less power and be a bit quiet, even so it is already. I use virtually silent' workstations from thinkmate since 2008. The current home one is probably 4 years old now. They are rock solid and work 365 day 24-7.
29-6-2019: It used to be that Mathematica would generate reasonable sized PDF's. In Version 12, GraphicsRow is in trouble:. Here is a test S1 = Plot3D[Sin[x y],{x,-2,2},{y,-2,2}];
S2 = Plot3D[Cos[x y],{x,-2,2},{y,-2,2}];
S=GraphicsRow[{S1, S2}];
Export["s1.pdf",S1,"PDF"];
Export["s2.pdf",S2,"PDF"];
Export["s.pdf",S,"PDF"];
Now look at the file size
-rw-rw-rw- 1 knill knill 44128440 Jun 29 21:52 s.pdf
-rw-rw-rw- 1 knill knill 259271 Jun 29 21:52 s1.pdf
-rw-rw-rw- 1 knill knill 246221 Jun 29 21:52 s2.pdf
25-6-2019: I recently traveled with a small external harddrive (5TB) (Seagate backup plus). They are nice little drives but also sensitive. There were some troubles after a drop. No wonder as they are mechanical platters. I still marvel at how small and still large these things have become. (In 2000, I still had a Next workstation with a 250 MegaByte harddrive.) Yesterday, I got a small 2TB external SSD (ScanDisc Extreme portable). Reformatted with encryption case sensitive, it is a big improvement even so the drive is still quit expensive (a bit over 320, while a 5T Seagate drive with platters is 110 dollars). The small 2TB marvel is about as long as a finger (3.8 x 1.9 x 0.3 inches). The data sheet tells that it is shock resistant up to 1500 G and temperature safe from -20 to 70 degree Celcius. I really like that it does not drain any power from my laptop if not in use (this is different from spinning platters). According to data, it is 5 times faster than the non-SSD versions. But it actually feels even better. For example, when unplugging and replugging in a non-SSD drive, there is a considerable delay for the drive to recover, sometimes even a few minutes (as the drive has to make some sanity tests). The SSD drive is immediately there.
24-6-2019: No more Raid for me. I had for more than 2 years now a nice little Raid rig at home (Noontec-TerraMaster D5-300). It worked fine for more than 2 years until 3 weeks ago, the drive would not mount any more. The individual hard drives are all ok. The software did not help and everything appears to be right. So, I had to reformat it and start all over again, the drive was back up after a few days of copying files. It worked only for a few weeks, then again, it failed in the same way. It must be a problem with the controller. For me this means now to forget raid. I will go for now with two 8 TB drives which are rsynced manually. This is cheaper. If one fails, well, just replace it. For long term backups, I use small 5TB drives which are encrypted, not overwritten and stored not in-house, nor in-office (and of course not in cloud). I was just recently happy about this: my media drive developed problems and then the RAID backup went down at the same time too (Murphy's law) leaving me stranded with long term backups.
20-6-2019: Summer is a good time also to upgrade programming languages. Because upgrades break things. Mathematica is usually quite good with keeping things intact. I don't mind things like that EulerCharacteristic is now defined in Mathematica 12. This requires me just to redefine procedures which were called EulerCharacteristic. But there are annoying changes: GraphPlot3D for example has changed how the objects are stored. This required to change any access of points like GraphPlot[s][[1, 1, 1]] to GraphPlot[s][[1, 1]]. For me it virtually breaks hundreds of programs. Admittably, GraphPlot3D looks better now, but it would have been more gentle to users to introduce FancyGraphPlot3D or leave the old data structure intact. One of the powers of Mathematica is that one can drill down into the details of a data structure as everything consists of lists and lists of lists etc like Lisp. An other thing just noticed is that PolyhedronData["Platonic"] lists now the Platonic solids in an other order than before. I don't see any reason why. It is now {Tetrahedron, Cube, Octahedron, Dodecahedron, Icosahedron} In Mathematica 11, it had been {Cube,Dodecahedron, Icosahedron,Octahedron,Tetrahedron} which was alphabetic. Now, it seems that the number of vertices were taken as an ordering parameter. It looks like a small thing, but every program written which used say PolyhedronData["Platonic"][[2]] ends up now with the wrong polyhedron. I did not scan my harddrive yet, but there must be dozens of programs (like for illustrations in courses done over the last 30 years) which are broken now. This is probably just the tip of the iceberg. The most annoying things are changes in the core of the language, but this fortunately did not happen with Mathematica. Once, in Switzerland, when I was in the cryptology group, (we were in the beautiful village of Linden), we programmed the most integer factorization algorithms from scratch in Pascal and while testing Morrison-Brillhard, suddenly things started to fail. We did not find a problem in our program. Drilling down showed that the Sqrt routine was broken. The team working on the basic core of the language had optimized that procedure and introduced a subtle bug. (All the integer procedures down to the detail were at that time developed and built in-house from scratch, not relying on any outside libraries. This is military after all). In any case, broken things are often a reason why programming can eat up so much time.
25-05-2019: Operating systems alerts are a nag, especially if you can not do anything about it. Why should you get nags "Your program" is not optimized appewear for your every unix routine which exists, as well as every old program which does no more have updates? Anyway, OS 12 allows according to this page,to supress these warnings:
 defaults write -g CSUIDisable32BitWarning -boolean TRUE
Update of 6/20/2019: this did not help. There are still nags. In general, whether it is a watch a laptop or desktop one should be able to be able to order it shut up about warning. Linux allows to configure this much better. iWatch OS has become better in this respect. [Update June 20, 2019: the above command still does not prevent warning messages. They appear just more rare.]
01-05-2019: Just wrote an email and in the text wrote: "I attach the file" but forgot to attach the file. The gmail system alerted me that I forgot the file. Usually, AI goes onto my nerves, as I hate if the system "assumes" to know what I mean. In this case, it was a pleasant surprise and a reminder that email systems read your email ...
18-04-2019: A new programming language without loops. We have seen that already. Niklaus Wirth built Pascal, Modula, then Oberon and things became more and more functional and elegant. But it was less and less and less used. I like to have choice. The idea of building everything functional is nice but it is good to be able to loop if needed. I try to program like that if necessary and say Map[Prime,Range[100]] rather than building the list with a loop Table[Prime[k],{k,1,100}]. The worst of course is P={}; Do[P=Append[P,Prime[k]],{k,100}]. Still, when building something more complex, I like the loop structure. It is cheaper to build, less elegant yes, but a language should not forbid it. I myself use it often. It can happen for example, that the evaluation of the inner part can take days or months. In that case, one wants to write out intermediate results. Here is an example:
P={}; k=10^70; Do[u=FactorInteger[k];P=Append[P,u];k++; Print[u],{10000}]
Now, Mathematica is very flexible but it does not allow to loop over numbers of the order 10^55. I had to circumvent by incrementing the index manually due to the limitation of the language. Still, it was no problem to overcome the limitation as the language allows loops. Also the name Bosque" is forbidding, as there is a Basque language. As for now, one can not find anything about it. There is an Example code about tic-tac-toe.
14-03-2019: The Pi day lecture on differential equations was an opportunity also to test my new go pro 7 camera. (It was housing day and most freshmen students could not make it to class). See this page. It is the first time, I was able to record in 4K with 60 Frames per second. What is really nice about go pro is the wide angle. See a lecture in the same room recorded with a traditional camera by the science center media team where the speaker is often out of frame and a camera operator was needed. I just had my bear babysit the camera. The picture quality of that little thing is quite good. The sound quality is not bad neither. An external mic might have helped a bit. There was one snag: the camera stopped recording after 40 minutes. I think it must have been due to a new SD card which had not been formatted within the camera This this discussion for example. There are entire videos about this issue. The recommendation is to reformat the SD card within the camera. I will do that before using it the next time for a longer recording and see whether this helped. An other possibility is that the 4K/60 frame is still too new (it was only enabled after a firmware update of the camera done the day before). For a lecture 60 frames per second is overkill of course but for action shots with slow motion, it will be nice.
26-02-2019: I like my scan snap scanner. I have one since they exist. The software has changed quite a bit over the years. It used to be that one could configure, at which DPI (dots per inch) or in which format or which document type one could scan. This is all gone now. I just happened, that suddenly all the pages of a document would be stored as JPGs. The reason was that the settings somehow were changed to "business cards" instead of "documents". That change determines now all the settings. It makes sense: most folks do not care or know about file types and their properties and one can not blame them. The operating systems have started to hide more and more too. One does no more see the file endings for example. Obviously, the scan snap software had been dumbed down" due to demand by the users. I would not mind. What is deplorable however that there is no way to be able to change the settings in a more obvious way. Simple" is good but pl3ease allow the user to drill deeper if necessary. Apple pretty much solved this problem by hiding stuff but by still allowing to modify things still when switching to a more advanced setting.
17-02-2019: There was a Slashdot article dealing with the annual letter of Bill and Melinda Gates. It concerns texbooks. Here is my own comment on slashdot. One reason I mention this here is because also Slashdot is an electronic service which might disappear at some point in the future (I hope not). Yes, one can question physical textbooks. I avoid them also as much as possible but there are still various issues with electronic texts: 1. Loss of control: Even with free versions of books or videos or resources, they can disappear at any moment. How many electronic resources which were available 20 years ago are available still now? I myself have the habit of keeping copies of everything I see electronically which I like because it can be pulled at any moment. Books don't just disappear. You can still read them in 50 years if they are converted first into a industry independent format. 2. Long term concerns: Having a private library however requires to have a good backup system, decentralized because one can not trust any service in the long run. I'm old enough to have seen many things come and go, terms of services change and it is only 25 years now, that we teach and distribute online (i had my first course websites for classes in 1994 and still have all these resources online, but how many things from 25 years ago are still there? The biggest shock for me was the pull of google video to youtube. It can well be that in 10 years, youtube is sold to an other company, or only available behind a paywall. Services like Kahn academy etc, we will have to see how long they are still free. 3. Privacy concerns: Even in the free textbook movement", one has started to look for ways to mine the information like tracking students readings. Like in e-books, the information what and how fast a reader reads, possibly annotates is used or sold. I personally do try to avoid such resources, because it is as if somebody constantly looks you over the shoulder. How long did I read what, what do I read? when do I read, where do I read? This information is all given away for free. How it is processed and stored is opaque. I know that even well intended projects for free textbooks start having students to register (yes it is free), but all this information is kept somewhere and evaluated. Who is naive enough to believe that this information stays confined. This by the way is the same also for online newspapers. I have concerns with being tracked all the time telling an anonymous entity what articles I read when and how and from where. 4. Screen and write technology: Electronic reading has become better with the emergence of tablets and good computer screens. It is still not there. Annotation with pen still beats annotation by electronic pens which can be sluggish and depends on industry controlled technology which changes still frequently. We will eventually get there, once the screen technology has the resolution, speed and comfort of paper. It is a matter of time only but it is not there. The tablets of today also run on operating systems over which one has lost control. Even well intended systems start to bug you to log in. Sorry. I keep all my library in a gold old fashioned directory tree which I'm sure I can read also in 10 years, which I can print out if needed and annotate with an old fashioned pen if needed. 5. Proprietary formats: One of the biggest problems with electronic reading is proprietary formats. I don't know how many different reading systems (apps) i have tried and which were abandoned or then bought by a big company which then only allows to use the service while registered. The best systems for writing on a tablet or screen are all proprietary and could disappear any moment. It is essential for example to have wrist protection technology when writing and drawing on a tablet. The pens have become great already, but the apps continue to disappear and appear. There were apps I liked which do not exist any more. Come on. If I write something, I need it to be available not only the 3 years of the life span of the app, I need to be able to read and modify it in 20 years. I have still documents written in software written by companies which disappeared or were bought by others. If the document was exported as a PDF and put on my own machine, yes, I can still read it. Other things have disappeared once one does not pay any more for the service. Or the app does no more work with the current operating system (more and more frequent nowadays also that the developers are long gone and no update available!)
10-02-2019: How UI design behavior has changed: I just got to a situation on Gmail, where the side menu suddenly kept collapsing. How does one bring the menu back? It used to be that one could change such behavior by using "settings" and change a flag. No more. We live in a time of riddles where UI designers love to be game designers. Fortunately enough others had that problem too. The solution is click on the Hamburger" (the three stacked lines to the left of the M symbol). I don't know why hiding things" has taken over so much. It took me a while to realize how to get to the print menu in chrome (the three little dots on the upper right corner are the key). It is just that for decades, UI design has had the paradigm that there was a menu bar. Now, once the menu bar is gone, one has the catch 22 situation to figure out how to get it back without the menu bar as the turn on-off switch had been in the menu bar ... In firefox at least, one can get it back by right clicking in the right place of the browser. Not so more in chrome. Now, as explained here, one needs to install an extension for getting it back. I can understand that some might want to have a cleaner browsing experience by not seeing the menu bar, but at least it should be configurable. There were similar issues already a decade ago with OS X design. There was a time, when suddenly the scrolling bars kept disappearing and also the hard drive icon of the computer went away. At least one could turn it back on. I can understand if hardware requirements requires an UI design changes like on newer iphones, where the start button is gone, one had to change the UI a bit but at least it had been done there so that has not to look up how to do it. [Update, for the new iphone, the way the control screen is accessed has changed also. It used to be that one could swipe from the bottom or the top to get the to it. The new version, I could not figure out myself and had to look it up. One has now to swipe down from the top right. Well UI designers have really become puzzle makers. ]
27-01-2019: In the fall, I had the opportunity to learn a bit more about Khipu, the talking knots of the Inkas. It should be mentioned also here in technology notes, as it is pure IT, and very modern IT. Information technology which we have discovered in our genetic code or in graph databases of the Unix philosophy of storing information in a directory tree have been pre-taken by Inka technology. In the last week of December 2018, I posted a few notes about this here [PDF]. The Khipu technology is not only fasciniating, it is also a great paradigm for many modern things.
27-12-2018: Youtube has removed this video because of some copy right claim. I would not mind that much. The problem is that they blocked without noticing me so that action can be taken, like a copy right dispute. In this case, I prefer not to make a copy right dispute as it is a small mattter and the background music not at all essential. Fortunately, youtube allows now to remove the music. Lets see whether the movie will come back. [Update: the movie came back.]
27-11-2018: I don't know of an other Oliver Knill, but I just saw on Amazon a an algebraic topology book which bears my name. I have not anything to do with this. I don't know any other mathematician with that name. There are very few mathematicians with the name of knill and only one with Oliver Knill (as far as I know). So this might be a scam. I submitted a fraud alert on the Amazon's legal part (reported infringement). It seems however that since names are not registered trademarks, this might not go through. Update: actually, I had been a bit too pessimistic. Amazon swiftly told me to have the entry to be sold (but the book is still listed). Update January 12, 2019: the book is still available. Quite annoying.
24-11-2018: The biggest problem in operating systems are still dependency hell" issues. My linux systems usually do fine for some years. Still, after a couple of years, there are dependency problems happening. On an office machine, convert" (ImageMagick 6.9.7-4) stopped working properly on large files probably due to a library update. Some of my apple systems (which run Mac OS Mojave) start to complain about unoptimized programs". The programs still work but might no more in the future: Adobe Acrobat 9 Pro for example was last updated in 2010 which I use regularly and does various things well which other programs don't (like optimizing PDF's, doing a reliable OCR). Now, upgrading to a later version is no option any more since Adobe moved to a subscription. Yes, keeping operating systems seems to become more and more challenging as the recent Windows 10 upgrades have illustrated.
26-10-2018: IBM to buy RedHat. Most commentors on the register are pessimistic and indeed, the prospect is not good for redhat. Getting absorbed in a large rigid structure has seldom been good. One can only hope that the work culture of the smaller company. In any case, IBM will buy a lot of talent. Maybe they have learned from previous mistakes: From Slashdot: "IBM acquisitions never go well. All companies acquired by IBM go through a process of "Blue washing", in which the heart and soul of the acquired company is ripped out, the body burnt, and the remaining ashes to be devoured and defecated by its army of clueless salesmen and consultants." We will see whether this will be true in this case. One can also learn.
25-09-2018: Tried out the Vivaldi browser. Refreshingly good. I still use Mozilla primarily. Vivaldi has a more intuitive interface and especially nice bookmark mangagement. Still, like Chrome it vastes URL estate by warning about non-https pages. It is good to have alternatives, especially as google started to tweek Privacy settings and do strange things with URLs.
20-08-2018: A small change in perl regex handling. I usually run a scripts to generate from a bibtex version file to an independent file (for example to submit to the ArXiv which needs the bibliography included rather than generated with bibtex). Until recently the following would work (from the command line or within an other script). The script replaces the bibtex entry with the content of a file:  perl -pe 's/\\bibliography{geometry}/cat file.bbl/ge' -i file.tex  This does not work any more, the curly brackets need to be escaped. The error message is: Unescaped left brace in regex is illegal here in regex; marked by  perl -pe 's/\\bibliography\{geometry\}/cat file.bbl/ge' -i file.tex  I love established and entrenched programming languages like Perl, which do not mess with the user (as even small changes breaks a lot of stuff). This is a rare case in Perl, where the developers badly mess with the users. Changing basic stuff like how regex stuff is handled in scripts should never be changed. If one googles the error message, one sees that this breaks a lot of other places. If the developer things something is handled not well, it should be implemented by allowing the user to set a flag enabling the new feature. Now, in my case, this is not that bad. I have to adapt that particular script only in 41 files, but I still don't know what other automated stuff will fail now.
06-08-2018: An article in Aeon by Nicholas Tampio provides some critique on "screen based learning". I think, there is a point. Real experiences with actual physical objects can give more insight. I myself believe to have got a lot more intuition about numbers by playing with Cuisenaire material (also in number theory) or Lego, Mecano, electronic boards, chemistry kits or building stuff. Books of course were also important. Of course, there was no web, when I was a kid, but TV instruction then is pedagogically essentially the same than Moocs today (just that you do the homework on paper and not on the screen) and that the lectures were broadcasted at a specific time (which prevented procrastination). The article mentions the book "Pnenomenology of Perception" by the French philosopher Maurice Merleau-Ponty who stressed the lived experience, the "doing" over the "seeing". I myself find such discussions always a bit tiresome when done in the abstract. It is difficult to theorize about pedagogy and learning. The real experience can be different. And one of the issues is raised in that Aeon article of Nicholas Tampi: real experiences, real people, real teachers, real engagement only comes with real interactions. This happens less when looking at a screen. Somehow, the screen can distract. I had just 1 and a half day without internet and phone at home because of some networking problem of our internet provider (at one point I was one hour on phone support). The issue got resolved. But there was one thing which was good. I was forced to focus on local things for once and used the blackboard for thinking and got an idea for a new proof of something. The topic of "screen based learning" might be complex, but as a general rule, keeping a healthy balance can be a good idea.
05-07-2018: Something about exploring creativity through computer algebra on Medium. It is also mentioned now on my creativity page. Related to computer algebra, checking for Hamiltonian property of graphs is hard. This can be illustrated with checking for the Hamiltonian property of the graph with vertices {1,2,...,n},where two nodes are connected if their sum is a square. So, far, the machine gets stuck when checking n=152.
15-05-2018: It is the time of the year to update a bit my machines. I upgraded two of my office machines from Ubuntu 16.04 to 17.10, and then to 18.04, both time with "update-manager -c". Went very well. The only snag was that from 17.10 to 18.04, the lightdm manager got lost. I'm still using the blackbox windows manager. Canonical announced to replace the X server with Wayland in version 20, but I guess it will be no problem then also to keep the X server running. Ubuntu 16.04 had been a very stable system. [Update 05/16/18: made also a home machine update from 16.04 to 18.04 in 3 steps. Needed a night and getting up a couple of times because the upgrader asks questions in the middle about configuration files. But things went well. Just needed to add the Nvidia graphics drivers "sudo ubuntu-drivers autoinstall". Some glitch with PERl which killed a morning: needed to reinstall perl although by running "upgrade" after "sudo cpan" and still have some library problems in PERL. How come, there is suddenly a "perl5" directory at home? I did not ask for it. Might be related to the PERL problems which came from a rather steep upgrade from 16.04 to 18.04. Needed to set the PERL environment variables by hand but still have libgtk3 problems. I might still have to do a fresh install of 18.04 after all, if there will be more issues.
30-04-2018: From a Mathematica workshop. Writing music with Mathematica
24-03-2018: The New York Times write about an other push of the Justice Department to Mandate a way to unlock phones. Its good that besides some Suites (Ray Ozzie and Ernie Brickell) also an expert (Stefan Savage) is on board. In technology and cryptology in particular, it is always difficult to say what is possible and what not. But in this case, it is not so much a technical issue. Whenever a second party (whether manufacturer or government or even some independent entity can open a device), then third parties can do it to. This claim can not be proven in general, it is just historically so many times happened. From the article: The idea is that when devices encrypt themselves, they would generate a special access key that could unlock their data without the owner's pass code. This electronic key would be stored on the device itself, inside part of its hard drive that would be separately encrypted - so that only the manufacturer, in response to a court order, could open it. I don't know but this looks like a very bad idea as if the system writes that access key into the memory, this part is accessible physically. Whoever thought about this assumes probably that there is will be some kind of decryption method known only to the FBI which allows to decrypt the device. So, what do you do then, if for some reason a third party knows how to do that? Suddenly, all phones, including the ones of the folks who came up with the idea, will be wide open to everybody. How long, until nobody will buy phones from US manufacturing any more?
18-03-2018: USB C multiplier hubs are almost not existent. I mean hubs which featuer additional USB C ports, not just the old USB parts. The ones one can buy are expensive, like this one. Virtually none of the cheaper hubs features additional USB C ports. A good hub would make the macbook more usable. Or then bring out the next Macbook with two USB C ports. The engineers seem not to get it. If the laptop is at the charger, one still needs an other USB C port for adding a USB C drive or device (USB C is faster, they will pick up anyway). The worst are the USB C hubs which don't even feature an additional USB charging entry as this means that hub can not be used for stationary use. Are there other reasons for this disaster? One could imagine expensive patents on USB C specifications or then technical problems with powering the ports. I myself have a NIGI adapter which fortunately features one additional USB C port. But the plug already wore out because I use it so often: at home I attach an external USB C hard drive for backup.
14-03-2018: To honor piday, I filmed a short story in a computer game. (The entire project is quite time consuming. Took in total about a day of work (filming and building a story). Assassin's Creed is well suited as the character can freely roam around. Unfortunately, one can not program the AI characters like the characters in the library or on the street but it is possible to tell a story. There is quite a bit of mathematics already built into the extension pack.
08-03-2018: The register honors the ZX81. As usual, the register title is hilarious: "10 PRINT "ZX81 at 37" 20 GOTO 10". But there is something nostalgic coming in. At that time, computers were REALLY exciting. Unlike today, where we just have incremental power increase, these were breakthroughs. I myself did not have the ZX81 but a tandy imitation. But what was nice is: you started up the machine and be right in a programming language. Yes, it was only basic, but you felt in control. It was a step forward from the TI 57 programming where one had to fight for each line of code in order to fit into the memory.
17-02-2018: Small is beautiful. The computation of all cohomology groups of an arbitrary simplicial complex in 6 lines. This compares with computations done in a triangle illustrated in Math E320 (see the [4 miracles Mathematica notebook].
04-02-2018: Just asked Siri who won the Super ball. Siri gave the last years results. Not watching TV myself, I had assumed that the game already took place and that Siri is just clueless. I thought having closed the conversation and exclaimed: "F..., you don't know". Siri answered: "Sorry, Oliver, I try to be better next time". After I found out that the game has not taken place yet, I realized having wronged the machine in error. The funny thing is that I felt really felt bad having shouted at it. Last week, a student suggested to me to ask the machine whether it wants to merry me. Siri: "Oliver, we don't know each other long enough." Good answer. A better one would have been: "But you are already married, Oliver".
08-01-2018: The Meltdown und Spectre CPU disaster (Supergau) produced a lot of discussion. This could be an opportunity for open source processors like . I bounced this once at a Heise forum. This is nothing new but the task would be formidable to be only close to commercial processors in performance. It is kind of a sad modern development in technology (also in Artificial Intelligence) that the development resources are so large that it has become a part of industry and is not part of academia any more. Now, we see one of the consequences of having these technologies done in opaque frameworks which nobody can examine or then only if it is too late. Not that open source is immune to gaffes but the risks are lower as more eyes look at things. Now we are fu..ed. There is no other word. I updated my linux machines and already see a performance drop and the machines of course are not secure. In the end, I don't think it will be too bad for the chip industry. They will be able to sell new processors like crazy once the new processors are out. Yes, there will be law suits, but essentially everybody will need new processors without speculative execution or implemented so that it can be disabled.
29-12-2017: An important article pinpointing one of the key issues in computer-human interactions: latency. It drives the user insane. We have computers 1000 times faster then the very early ones but latency is larger. Even if its the very tiny delays when typing. It is one of the main reasons, why minimal windows managers and linux are great. On linux, one can control any processes which delay.
23-12-2017: This is the time to try technology. I was reluctant so far with buying an iWatch. Gave it a try. It is quite good. I like Gaia, the GPS hiking app. I have been experimenting with small GPS devices for running in the past and it GPS not always connected reliably. This is also the case for the iWatch. Still needs to have the phone present. The greatest problem with the iWatch so far is that the inability to close some apps. Some don't want to quit. The apple outdoor app for example can not even be killed by rebooting the watch. Also Sudoku and 2048 (which are both nicely adapted to the watch) can not be reset. I had to remove them. Still don't know how to disable the workout app.
23-12-2017: My iphone was set to HEIC format. Now I have to convert hundreds of pictures to JPG. It is possible to set the camera preferences to JPG (compatible format) but in a recent IOS upgrade, it must have automatically pushed to HEIC. I use now the converter HEIC for the few hundred last pictures done in HEIC. It will probably take some time until image magic will convert things. I use for now the free "iMazing HEIC converter", which works quite well. Still it would have been a nice curtesy of apple to inform the user that they get pictures which can not be opened by most applications.
22-12-2017: I like firefox and support it as I don't want the browser to be dominated by a single company. The war on non-HTTPS URLS is annoying however. I can with firefox no more login to my router (which is of course not HTTPS) as it is on a LAN). Now, if I access the page, a warning dialog appears which prevents actually to enter the password. And then, since clicking away the dialog counts as a login, the router shuts down. Also, changing to HTTPS is not as trivial as it might appear. I have recently changed a tiny wordpress blog "quantum calculus" (60 pages only) to HTTPS, but since every linked image has a http: URL, I had to change this by hand and still missed some. In general, it is not the business of a brouwser to educate the user. The next step will be a warning message every time a non HTTPS link is accessed. Get a grip, firefox, not everything needs to be encrypted. If they don't stop this, I will delete you for good and compile my own.
21-12-2017: Something posted to this article. Why do we need a machine which does all? I need a workstation which is always on, does its daily chores, where I have a gorgeous large screen, which can also be used to watch a movie. I need a laptop to write with a clear screen without greasy finger prints. I like to touch the screen when consuming content on a tablet, but when working, fingers are forbidden on the screen. I need a tablet to read larger books and I need a phone to quickly look things up or to communicate. The phone needs to be small so that I can always have it with me, the tablet large so that also diagrams can be read well. Combining things always means to compromise: we have had printer-scanner combinations. They failed for both tasks. It is better to have a cheap and small reliable laser printer and a good reliable scanner which knows its stuff, can OCR, is fast and reliable. The prize of a device can be justified if it saves time, winning half an hour a day means 150 hours a year. Time is money too. For a laptop especially, I need reliability, a strong keyboard, a good screen. A 1TB drive would be nice too. But because there is lots of wear and tear, I personally prefer to buy relatively cheap but still good laptops and replace them frequently, delegate tasks which need heavy CPU or large amount of disk space to the workstation.
18-12-2017: Perl is 30 years old. A Heise article laments about the enthusiasm for the language. I agree. Perl is a great language. One of its strenghts is that it is stable. Happy birthday. Like a swiss army knife, it is a powerful tool and amplifies the shell. It is maybe no more fancy, but it does not matter what the masses think. A language which is 30 years old and still going strong deserves respect and also investment. At least it is safe from "rennovations" which destroy old programs. I can count on that scripts I wrote 10 years ago will run in 10 years still. I maintain a few "old fashioned websites" like rhetorik.ch or rheinfall.com or blogs like this one on graph geometry or course websites like This and then larger ones. All written in perl, some of the code almost 20 years old. But I have since decades not to spend ANY time on sysadmininstration. It runs by itself. I can focus on the content and the math rather than having to maintain stuff. Yes, content management systems, especially written in PHP, have taken over. Even so, I also maintain such a wordpress blog, quantum calculus, there are disadvantages of CMS: pages written in Perl are "documents", they are static, periodically generated pages which can be ported anywhere, independent of technology. They are documents which can be referred to. They are also FAST, very FAST. And stable and less vulnerable to attacks. 12-18-17
02-12-2017: A wise recommendation: keep paper backups for voting.
23-11-2017: A good article on the intel Management engine disaster. Nov 23. Some background about this troubling technology is given here. The talk of Joanna Rutkowska is here. It starts with "Personal computers are extensions of our brain. They are insecure and untrustworthy". An example of a well given presentation. We usually have assumed that hardware is trustworthy. One of her conclusions: today we can not assure secure boot. Rukowaka tells: "ME is an ideal backdoor and rootkiting infrastructure". It is part of "zombification" of computing: the hardware contains operating systems, which nobody can look at and which nobody can disable. Not even a secure OS like Qubes can prevent ME to take over.
21-11-2017: We are on the brink of a most terrible technology decision: the repeal of net neutrality. A NYT article puts it well: the internet might become a "pay for view" technology, at least in the US. Why a single person like the boss of FCC (a proven lobbyist of Telecoms can make such a decision on his own, is totally beyond me. It might lead to a much weaker US economy in the long term. There were other attempts of bad decisions recently, like health care changes which border at making it appropriate to call the lawmakers terrorists as it would have terrorized a large part of the population: (the definition is "the use of violence in the pursuit of political aims, religious or ideological change".) About 25 million would have lost insurance meaning the death of tens of thousands of Americans. Definitely much more than 911. (John Mc Cain with his famous midnight vote "thumb down" probably saved more lives than any general in the history of mankind). As taking away health care obviously kills people, it is an act of violence. It is not stabbing somebody to death, it is just watching the person bleed to death without doing anything and that is violence too. Changing net neutrality will not kill people, it will kill businesses. Maybe not world wide, as other countries are not that stupid. One can just say, it is not only idiotic, it is also deeply unpatriotic. Here is an article in "Entrepreneur" explaining a bit the small business aspect. And from the many cartoons:
12-11-2017: A nice article about augmented reality ("data-vomit gush"). There is especially a link to a movie showing the first experiments with virtual reality by Ivan Sutherland from 1968. It is related to the MIT Lincoln Labs in Lexington. Sutherland is also known for Sketchpad. Currently, the European tech sites like the Reg or Heise kick ass. Heise just now has a nice article about how Face ID was cracked with a mask. By the way, when looking back at these historical videos, it becomes evident how much ahead universities (like MIT) have been at that time! Now, cutting edge technology is outsourced to companies. This happens also at an amazing speed also in higher education. They don't even try to fight. It makes of course sense financially to outsource IT, to outsource mail, to outsource course websites technology, even to outsource teaching. But it will soon be mean the end of a golden age of "higher education" as a place where innovation happens. Impossible? We have seen it happen in the automotive industry. It is not inconceivable that in 50 years, Boston is the new Detroit. If this looks ridiculous, just look at how far ahead the Lincolns Labs were in 1968. Companies like Microsoft (1975) or Apple (1976) were not even conceived then. P.S. There had been previous times, where industries were ahead of the game. IBM, Xerox or Bell labs come to mind, so, it is maybe not such a new thing. It is just the scale which is much different.
11-11-2017: Installed High Sierra on one of the macs. I think the system is now faster. No problems so far. Actually quite amazing as so much has changed under the hood. As I had performance issues with Keynote on my laptop, I also upgraded the laptop. Maybe it can now run Zoom and Keynote at the same time.
11-11-2017: A bit modified comment posted on this story: What I want from a programming language are Standard, Stability and Speed. Nobody minds the little quirks, redundancies or the lack of elegance. When I program something today, I want it to run in 10 years, without modifications! In particular, I want the language to be around still, the grammar once put stay a standard. I want the program to run stably. In particular, I expect developers to be VERY VERY careful when changing the compiler. Even small changes annoy. C has been quite good but recently, it was no more possible to run gcc -lm example.c . Linking the math library required gcc example.c -lm. WTF. One has to change now 700 Makefiles just because somebody thought this is more elegant? I don't mind if a language is extended or sped up, but don't for change old grammar, not even the smallest things. There is lot of code around which would need to be fixed. I'm in particular cautious when adopting new language, even if it is only a wrapper. They first hype and spike. In the worst case, the developer gets over excited and changes the language again and again. In the second worst case, the language gets abandoned. A language needs to earn respect, prove that it is stable over a long period of time, that it is reliable and fast.
06-11-2017: My Zoom Setup for teaching Math E 320: A picture from Monday, November 6, 2017. I had problems to run both Zoom and Keynote on the same laptop. I currently feed the slides from a second laptop which joins the meeting too. There is a large monitor attached which makes things also more comfortable. Click on the picture below to see it large (10 Meg file).
24-10-2017: Some extended comment to This register article: The analogy with utility is deeply flawed. Information is not a utility. It can be (1) sensitive and (2) crucial (3) requiring big pipe capacities and (4) require a healthy IT culture to be handled properly. We have played as a clueless kid on mainframes asking "mommy" (sysadmin) for computing time have been autonomously and educated and return now to the nursing home, paying the nurse (cloud provider) for every second of service (computing time).
1. Information is not a utility. Water, gas or electricity do not contain possibly sensitive information, which needs to be protected. If a utility provider goes down, it is bad but not deadly. Losing data in a "cloud" or having data diffuse away to a third party, can kill a business as leaked information remains leaked for ever. If one of the major cloud providers loses control, it could even lead to a recession as many businesses would fail. Water, gas and electricity are information-free quantities, data files are not, they can be personal and crucial for a business.
2. Information technology is vital. A power station going down or a water pipe gets repaired is a temporary inconvenience. Data loss or data leak is unrepairable and would be especially bad for financial, health and educational sectors. As a private person, I can survive for weeks without internet, electricity and gas, even water and still keep up essentially the same productivity. A modern laptop can be powered by solar, it is possible to work even in candle light and water could be bought in bottles. Such a resilience for IT is not possible with cloud IT.
3. Information pipes are way too narrow An big problem with delegating IT to third parties is the internet infrastructure. Especially in the US, it is weak and expensive. The last mile is the main sore point. For any utility like water, gas or electricity, the capacity is not a problem. Now, with net neutrality currently dying in the US, it will even become worse. We will have to pay more, maybe even more for backing up large amount of data on a foreign data server.
4. Lack of a healthy IT culture. A consequence of delegating things elsewhere is a loss of IT culture. In the short term, it can make sense as still, the cloud suckers dump the prizes to keep people hooked and destroy local IT infrastructures. Once dead it is difficult to build it up again and higher prizes are likely to follow. Yes, it is good that we don't have to uudecode an attachment by hand any more and that most computers now have almost zero maintainance, that backups can be automated onto a time machine etc but it also means for many institutions that the IT culture is shored out.
22-10-2017: The exhibit Can you hear the sound of a simplicial complex uses MP3 files triggered by mouse click. I first used "onmouseover" but sound is in general annoying in webcontent, when appearing unexpectedly. Most of this page was generated pretty automated. The eigenvalues of the matrices corresponds to the sound frequency. Mathematica generates the sound and image files.
17-10-2017: The limitation of twitter to 140 characters is a standard which should not be given up lightly. We have a new unit, "the tweet". If twitter will change it to 280 characters, it should be called differently, like a "roar". Limitation is an interesting challenge, especially in code. Sometimes, one has to fight a bit, like in this post on the energy theorem. I had to leave away the semicolons, after the definition of the connection matrix and the definition of the energy. But I wanted to cover the complex given at the beginning of the talk about this energy theorem. I think twitter would make a "cultural" mistake as 140 characters has become a "cult". I wonder what the tests will reveal.
26-09-2017: After upgrading Keynote, it started to have some hickups when exporting a movie. See here. Keynote has improved a bit the performance. When using Zoom, I have had terrible problems, almost bringing down my machine. I still now present from a second computer as Keynote sucked all resources from the machine (a brand new macbook). Unrelated is the problem that keynote uses a lot of resources with large presentations. I have problems running it on the same machine together with Zoom, while teaching. My solution is to run a second laptop on a second account, join the meeting from there. The second laptop is only used for presentation and has no video in zoom. This works.
18-07-2017: Links for a technology demo for today: An animated picture Strong lattice Fluid dynamics fluid Bubbles Vortex Sphere Surface cloud
11-07-2017: An important message of Vi Hart:
11-07-2017: I use my 12 inch macbook every day. Maybe 5-6 hours per day in average. Now 2 years old, there is now a battery service warning. Yes, the battery empties faster (5-6 hours now rather than 10) and looks fine but still, it seems that life will not last too much longer. Also the keyboard shows its time. I type a lot. Some keys lose their key marking which is not a big deal, others have started to become less reliable. I cleaned out some like the space key but removing it risks breaking up one of the tiny plastic latches (which happend to me). The keyboard would also need to be replaced. The risk is now here that one of the keys breaks for good making the laptop unusuable. I have done replacements of individual keys for mac air laptops before but it is quite expensive. To service the battery, 200 dollars, to replace the keyboard again at least 200, then the time to schedule appointments with the genius bar etc, a couple of hours and having the laptop not available for weeks. It would just not be feasable. I decided to use the still well working laptop now as a backup machine and get a new 12 inch one. The strategy to buy relatively cheap laptops but replace them regularly appears better than having an expensive one (Pro) but still face the same long term problems like battery, harddrive and keyboard, which just happen to fade after 2-3 years of heavy daily use. I use also the same strategy for bike which drives has at least 3000 miles per year. (I drive rain and shine, snow or heat, every day). After 2-3 years also, the bike starts to fail everywhere and servicing it costs half of a new one. Also here, "buy relatively cheap but replace often" appears to be more effective than having a really expensive one. Then there is the risk of having it stolen, which both for laptops and bikes are just there and which just would be devastating with 3 times more expensive laptop or 10 times more expensive bike.
04-07-2017: A vulnerability in RSA incryption illustrates that not only the mathematical security, but also the actual implementation is important. In this case it is the way how the modular multiplication is done. This allows to recover some of the bits. Important work as crypto security is crucial for a functioning society (banking, trade, health care, voting). See the Heise.
22-06-2017: Why does one use ∞ in HTML while TeX uses \infty? The discrepancy is kind of annoying. The infinity symbol was introduced in 1655 by John Wallis. But who is to blame for the incompatibility? I think it might have been HTML as the Unicode Consortium was incorporated in 1991 and the first versions built in 1986-1987. TeX was released in 1978. ASCII came earlier but does not feature the infinity symbol (which is kind of a shame if one looks at the other things which have been chosen instead: in the List of ASCII codes) . Apropos: the incompatibility between different languages is not a biggie. The extended ASCII flavours however were and we still have to suffer from the sins of coorporations trying to embrace and destroy competition and invented their own character or even ASCII versions. Still today, both in Adobe as well as in Word texts, one has characters like -, ", which look ASCII but are not. Platform specific character codes remain annoying. It is good that both the unicode and W3C consortium have got their grip together.
17-06-2017: Having switched my 4K monitor as a second monitor for the mac, I have tried a curved monitor (Dell UltraSharp U3415W PXF79 34-Inch). With a 3440x1440 resolution it does not match my 4K monitor with 3840x2160, but actually (maybe because my eyes also get older), I prefer to have a bit of a larger font while working. The widescreen (21:9) aspect ratio is very comfortable to work with. Here is a screen shot (click on the picture to see the full 3440x1440 pixel screen shot):
16-05-2017: A rare event: youtube is down. Interesting error message, (for google developers to debug): (click for larger picture) .
15-06-2017: A heise article illustrates how Etherum has heated up the crypto currencies. Ethereum is a gold rush, while bitcoin tanks (for now). These things are always a bit of a pyramide scheme but the block chain technology looks hotter as one can run code in decentralized applications. It also allows to build smart contracts. The Etherum virtual maachine is a turing complete software which can run any program it is kind of like a universal Turing machine. This makes it interesting in a more general sense. The Ether currency shows exponential growth ether or bitcoin.
10-06-2017: The SEO optimizers have become more sophisticated. It used to be stupid. But today, I got a personal email from a "math student" who for a "geometry project" needs to have a page linked to get "extra credit". Who does not want to help a student? The page however did not look like a project page. Yes, it had some information on it, but not done by a student and only remotely related to geometry. I asked back for the name of the school and the name of the teacher, but it was probably a waste of time. Must have been spam.
01-06-2017: An article in NPR about soundtracks produced by computer composers. This is fascinating. We have for a couple of times used Mathematica to compose. Examples> See also the lectures on Music and Calculus and AI.
31-05-2017: An other 5 hours of rebuilding my office machine. Since this is unpredictable, it is good to do this between semesters. While switching hard drives, one of the SATA cables broke off. It was the Sata connector to one of the important drives which got stuck in the part of the cable, killing both the cable and the drive. I got really mad because it was a nice new harddrive. I decided therefore to get one of these hot swappable harddrive containers (IStar 2BAY 2 x 5.25 To 3 X 3.5 Cage) and also got new sturdy SATA cables. Since my workstations are silent Thinkmate machines, I was worried that the additional vent would be noisy but the enclosure shields it well. I did also a fresh install of the operating system as my SSD has gotten old. Some minor surprises in Ubuntu 17.04: Perl ignores now by default local libraries and local files. An entry "export PERL5LIB=./:\$PERL5LIB" in the .bashrc file solved this really annoying feature. It was the @INC variable which is set when Perl is installed and which does not look for local libraries any more. What were they thinking? An other hick-up with the ftp server which accepts pictures from the LAN webcam. I should have known. It is not the first time, but if the configuration file (here /etc/vsftp.config) has not the right permissions and not owned by root, the server does not start up (without complaining). Ubuntu now talks too much, everything if one does ssh's into the machine. The chatty motd scripts are in /etc/update-motd.d. One could delete them but they might be handy at some point. The easiest to shut this off is to edit a file /etc/motd containing what one wants to display. Now it just gives a line telling when and from where the last login was. Also took the opportunity to upgrade Mathematica.
26-05-2017: It is rare these days to get into the case sensitive trap on OS X. I regularly sync a work directory from my office machines with my laptop which has a non-case sensitive file system. If two files like g.pdf or G.pdf are present in the same directory, one will bite the dust. It is usually no problem but I just got bitten by this once more. I format external drives on the mac with case sensitive file systems but it might still be a risk to do that for the main drive. OS X is well done and almost perfect, but the case sensitivity is one issue which needs to be solved.
24-05-2017: Spent an afternoon with a strange bug on my home machine. For some reason, the ubuntu installer always produces a garbled screen. The machine is fine, the graphics card is fine and works both under linux and windows, the install media are fine (work on an other machine. I excluded USB problems by using various flash drives, or USB harddrives, tried out various other BIOS settings and then also used an other monitor. I currently suspect that it is a low level graphics card mode which is buggy, either on the motherboard or then on the graphics card. Any way, an afternoon gone.
12-05-2017: Our phones are now voice over IP. It is funny how the information leaflet mentions "voice mail service has moved to the cloud". Dudes, it is just VOIP, web, internet. But I guess, now everything has to be the cloud due to marketing reasons. One of the arguments against VOIP had always been redundancy and that things work even if the network is down. But as now most have cell phones, a traditional phone line in case of emergencies is no more so important.
26-04-2017: The registar of today mentions the plan of Ajit Pai (head of FCC) to kill net neutrality. No wonder, this guy was close to Verizon before going into politics. It would not surprise if he still is close to their lobby. Killing net neutrality could be one of the worst consequences of the Trump presidency which so far has a common theme: totally unqualified people are put into positions they never should be in. Even the relatively conservative "The Hill" calls it a "war on consumers". EFF calls the proposal "devastating for competition, innovation and free speech". Indeed, its consequences could be terrible both for the economy as well as for democracy. It is time to contact the representatives.
18-03-2017: The Google JPG encoder Guetsli is everywhere in the news. Here is the google blog and here is the paper explaining the iterative optimization. I could not compile it from scratch on an older ubuntu 14.04 but on OS X, it compiled well. A test with a first picture gave 7 percent reduction from 29981 Bytes to 27969 bytes. A compression with this picture did not go through yet. Probably too large. For the smaller version it took 40 seconds to reduce from 162589 to 120391 (35 percent). Not bad. But for the larger 12 Meg picture, a reincoding would take an hour. It would take days to reincode one of my panorama pages. It is not the first time that a swiss name has been used. There is also a Zopfli compression algoritthm by google. Why Swiss names? Some of the Google researchers like Jan Wassenberg are based at Google Zuerich. Wassenberg came from the Fraunhofer Gesellschaft, German research organization. The JPG 2000 data compression standard came from there which has, similarly than Guetzli a small compression advantage. It largely failed however because hardly any browser supports it (Firefox and Google chrome does not) and also because it is riddled by patents, which is a death sentence. [Update: In a test with a large panorama with 12 Megs, Guetsli worked for 2 hours and got out a 14 Meg version. The algorithm definitely seems have to have difficulty with very large files.]
12-03-2017: I do essentially all my work from a terminal. This is why crashes of the terminal app are especially annoying. I use xterm since about 30 years and it had always been stable, one all platforms, even on thin clients or over slow modems. OS X Sierra is the first exception. It is a known issue. I find it happening more frequently when editing files with long lines. Fortunately, unix apps like vim have built in recovery so that one does not lose data, when writing a program. It is still terribly annoying and the stability of fundamental apps like terminal should have the first priority. The issue has been known to apple since last fall.
26-02-2017: When trying to upload this clip it took only seconds for being banned from youtube. While this spoof was accepted (with adds), the Rammstein clip is seriously protected. One definitely has to accept evenso, I believe fair use still applies: no monetary part, no damage for the producer. It is maybe not sufficiently small.