A bit of fortran and GR

I finally got off my ass and figured out how to use arrays and matrices in fortran, beginning from how to write them and read them and so on. I was trying to implement a simple linear algebra solution, that we had already done in C and python. I was frustrated most of the time because of the inconsistency in using the various loops, in defining variables and so on. I don't know how much ANSI C has changed in the last 10 years but from the looks of it, Fortran has. But I did find an interesting implicit method to read arrays in the in the mess, very functional and minimalistic.

On the other hand, as I've been doing over the weekend, I shall continue to write about the various metrics used in GR and their relevant christoffel connection symbols, reimann tensors and ricci tensor and ricci scalars. I read grtiny.pdf or the No-Nonsense introduction to general theory of relativity by Sean Carroll and was spurred on by it a little. But in general, I want to document all of this, preferably online, because I am bound to forget most of the things and I don't want to have to do all of the bull work over and over again.

I have an exam tomorrow so I'll get started on a couple of side projects tomorrow. Until then...

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