Blog

My thoughts and experiments.

© 2020. Dmitry Dolgov All rights reserved.

The Knife

I really don’t know how I lived before without pandoc. It’s an amazing tool, that saved me from a terrible pain of latex -> MS Word convertion. If you’re writing many scientific documents in latex format, and faced with the demand to convert it into MS Word, you can understand me. It’s like a tiresome point-and-click game, which can consume unbelievable amount of time.

Pandoc can do it, and I’m not kidding. All you need is to create a source file in markdown format and copy all latex formulas. In this post you can find several details.

Compare incomparable: PostgreSQL vs Mysql vs Mongodb

As such, there’s really no “standard” benchmark that will inform you about the best technology to use for your application. Only your requirements, your data, and your infrastructure can tell you what you need to know.

NoSql is everywhere and we can’t escape from it (although I can’t say we want to escape). Let’s leave the question about reasons outside this text, and just note one thing - this trend isn’t related only to new or existing NoSql solutions. It has another side, namely the schema-less data support in traditional relational databases. It’s amazing how many possibilities hiding at the edge of the relational model and everything else. But of course there is a balance that you should find for your specific data. It can’t be easy, first of all because it’s required to compare incomparable things, e.g. performance of a NoSql solution and traditional database. Here in this post I’ll make such attempt and show the comparison of jsonb in PostgreSQL, json in Mysql and bson in Mongodb.

Gentoo and Lenovo u430p - the sad story

Finally, I decided to replace my old laptop, and my chose fell on the Lenovo u430p. As I understand now, it was not a good idea in case of Gentoo =) Actually, I was surprised, how many nerves you can lose only because of the adaptation of you hardware to your requirements. And here is the shortlist of what you shouldn’t forget, if you want to do the same more easily.

Use an exception instead of the NaN

This is a small notice about a very useful trick. I often have to deal with computations, because the CFD is the part of my activity. And one of the annoying problem in this kind of research is when after many hours of computations you got a Not A Number result, caused by a stupid mistake. It would be nice, if a computation was interrupted by the NaN.