Posts about Computer (old posts, page 15)

I had my first computer with 5 and started C programming when I was 13. Then I made some simple websites using PHP which grew into ever more complex ones. In 2007, I created some Java applications, some of them are still among the portfolio on this page. While I was an intern at the DLR, I started to learn Python and IDL, which introduced me to matrix based languages. For the numerical methods lecture and especially my bachelor’s thesis I used C++11. During my master’s thesis I have learned Haskell for fun. Later on for my PhD thesis I also learned R and the Wolfram Language.

This section of my site is for articles about programming practices and performance tests. Also various stuff about computer hardware and software.


Bei Epic Games gab es GTA 5 neulich kostenlos. Nachdem ich mit GTA 4 eher mäßige Erfahrungen gemacht hatte, wollte ich es mir vorher nicht kaufen. Aber so kann man ja einmal testen.

Zurerst musste ich einen Account erstellen und den Epic Games Launcher herunterladen. Das scheint eine ziemlich fette Anwendung zu sein, die man nicht unbedingt auf einem Arbeitsrechner haben will. Da ich auf dem Spielerechner aber schon Steam, EA Origin, Ubisoft Uplay und GOG Galaxy installiert habe, macht es dann auch keinen Unterschied mehr.

Für die Installation von GTA 5 braucht man knapp 100 GB Speicherplatz. Also gut, dann geht das Spiel halt auf die große HDD.

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Note-Taking Software

There are a lot of tasks which are so simple that most programmers think that they can just set out and write their own. One of this is note-taking software. There are a couple products out there, but none are quite perfect. And instead of improving one of the existing ones, it is tempting to just start with their own. In the end, of course, there will be just one additional niche solution that only really works for the programmer but not the next user.

Sometimes there are conflicting requirements. Like you want something that is WYSIWYG or not, should it be in the cloud or private. Yet many other things could be made configurable.

I often take notes when sorting my thoughts. That could be as part of my dissertation, drafting blog posts or comparing products when buying something. And now I am looking for a note-taking software that I can use for my dissertation and in the progress I get a blog post out of that. Guess that checks all the boxes then.

My workflow generally consists of writing structured text and adding screenshots, inline math and code snippets along the way. I will compare a few products that I have tried out for note-taking.

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Hard vs. Soft Line Wrap

When editing text, I have been using Vim so far. My text documents were either Markdown, reStructuredText or LaTeX. All of them are just source code in some sense, the output format HTML or a PDF in a browser. Single line breaks do not matter in either format, it takes a blank line in between to separate paragraphs. Therefore one has the freedom to insert line breaks within a paragraph at will without it meaning anything semantically.

For a long time I have used hard line wrap. This means that I let my editor insert a line break after 79 characters per line, limiting the line length to 80 characters (including the line break \n). The alternative is soft line wrap where the editor does not insert line breaks into the source code but just virtually wraps the lines for display such that it fits. This latter approach is what one is used from word processors like Microsoft Word or LibreOffice Writer. Also it is used in virtually all web forms.

The soft line wrap looks like the following picture in an editor. You can see the line numbers and as such each paragraph only has a single line number. The text is wrapped in a soft fashion that is just done to fit the window for viewing.

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Markdown Editors (on Fedora)

I use Markdown a lot to create notes and reports. Since April I also use it for my website. And actually I write my dissertation using Markdown as well. All this time I have been using Vim for editing all my text files. For Markdown I wanted to try a few GUI editors with instant preview.

Although there are tons of editors and Fedora Magazine has tested NoteKit, Joplin, MindForger, Remarkable, Ghostwriter, UberWriter, Marker, and Ghostwriter, not all of them are in the Fedora repository. Only Apostgrophe (apparently formerly UberWriter), Ghostwriter and Marker are in the Fedora 32 repository. As there are already enough choices, I did not go to install more external repositories. By searching the package index for “markdown” I was able to also find Notes-Up.

I have used each of them for a bit and want to share my impressions. So far I still use Vim for most of my editing, but I found it nice to work with Marker and Apostrophe for a change.

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Headsets for Every Purpose

Over time I've accumulated a unsettling large number of headsets and headphones. And unfortunately I have yet to find the one that performs well with all tasks. Likely this is not even possible as there are just contradictory requirements. So at the moment I have four different ones which all have their niche.

The best sounding headphones that I have are the Sony WH-1000XM3. They just sound really great and have active noise canceling. I use them in the office and on the go. They connect via Bluetooth to my phone and I can also use them for calling. As they have built-in microphones and were rather expensive, I'd expected them to perform good in phone calls. However, they audio quality sucks so badly that people regularly tell me that they just cannot understand me. So I just cannot use them for calls. Then the Bluetooth chip in my laptop is so outdated (from 2011) that it can only connect via some fallback audio protocol and I can only use them as headphones, not as a microphone. And quality is worse than with my phone. So with the laptop I sometimes use the cable to connect them.

The Sony headphones have pretty much replaced my Sennheiser HD 485. These were fine for the budget that I had at the time. The ear cushions have dissolved over time, so I replaced them, and the new ones are also rather dissolved by now. Guess they were not built to last in this price segment. I did like the sound at the time, but I dislike that one cannot take off the cable on the headphone part. A broken cable therefore means soldering work. Their advantage at home is the acoustically open design, though. This means that I am not completely shielded from ambient sounds but rather hear my own movements. This is more relaxing at home, also I can hear when people try to talk to me.

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Video Conference Experiences

During the pandemic I work from home, just like most office workers. To keep in touch we use video conference tools. But as we did not have anything set up before, we needed to find something that works sufficiently welt. Also with the GDPR it is not that easy to just take anything.

It turns out that none of the tools are quite satisfactory, there always is a bunch of friction.

The first that we tried is the DNF Conf system by the German Research Network. It uses WebRTC, is hosted in Germany and fulfills the GDPR requirements. Also it supports presenting PDF documents. Unfortunately it has been hopelessly overrun and it took a month before they ramped up resources and users went to other services such that it is mostly usable now. On my laptop is uses a lot of resources.

The second thing that we have tried is Jitsi Meet on their site and then also hosted an instance on our own. I like this the best so far. It also uses WebRTC but supports keyboard shortcuts for muting the microphone and even has a push-to-talk feature. But somehow the resource use is quite high and the members of our group with flaky internet connections would be cut of all the time.

For Android there is an app, that seems to work just fine also. I have used it occasionally and am quite happy with it.

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