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c_vs_fortran

Anonymous (anonymous@undisclosed.example.com) — 2019-12-21T23:59:27+00:00

C vs Fortran for scientific computing When I tell people that I have used Fortran for a project, they are often surprised. One of the reasons is probably that they are used to Fortran 77, which is not all that user-friendly by today's standards. However, Fortran has seen quite active development over the years, there's Fortran 90, 95, 2003, 2008 and even 2011. The change from F77 to F95 was probably the most drastic one. Just to give you an idea: in the latest versions, you can create abstract…

computational_scientist

Anonymous (anonymous@undisclosed.example.com) — 2019-05-03T21:07:13+00:00

Becoming a computational scientist Note: the text below is copied from Appendix A of my PhD thesis from 2015. I have now been working on computational science and computational physics problems for more than six years. What has surprised me, in hindsight, is the great number of things that one has to be familiar with in order to be productive. The reason is probably the relatively large amount of DIY (do it yourself) in computing, compared to other disciplines. Below I will try to summarize wh…

fortran_improvements

Anonymous (anonymous@undisclosed.example.com) — 2018-04-25T12:46:33+00:00

Ideas for Fortran improvements Default values for optional arguments Currently, default values for optional arguments have to be handled like this: subroutine test(n_arg) integer, intent(in), optional :: n_arg ! Default is 10 integer :: n_used if (present(n_arg)) then n_used = n_arg else n_used = 10 end if ... ! Do something with n_used

fortran_programming

Anonymous (anonymous@undisclosed.example.com) — 2018-10-25T10:43:26+00:00

Fortran programming material Links to resources * * * Recommended books/tutorials for beginners The differences between Fortran 90 and Fortran 2003 (or newer) are not that large, so tutorials on Fortran 90 should still be a good starting point.

fortran_var_arguments

Anonymous (anonymous@undisclosed.example.com) — 2015-11-19T10:44:01+00:00

Reading a variable number of elements in Fortran The code below locates the content in an input string. The in-arguments are the line to be read in, the maximum number of entries and a string with delimiters. After performing the routine, the out-arguments are the number of entries found, and two list of indices: startIxs(i) holds the starting point of entry i in line, and endIxs(i) holds the end point.

my_setup

Anonymous (anonymous@undisclosed.example.com) — 2023-11-10T13:42:44+00:00

My setup Desktop Decription Choice Operating system GNU/Linux Distribution Debian Window manager XFCE Editor Emacs E-mail client mu4e Keyboard I use the Colemak layout (but with Caps Lock as Ctrl). [Colemak layout]

postdoc_fellowships

Anonymous (anonymous@undisclosed.example.com) — 2021-01-27T14:39:00+00:00

Postdoc fellowships in the Netherlands * NWO Veni - Applied and Engineering Sciences * NWO Veni - Science Domain * Marie Curie individual fellowships How to apply Useful links * (Funding calendar)

progression_of_time

Anonymous (anonymous@undisclosed.example.com) — 2019-04-08T19:59:51+00:00

The progression of time Time goes by pretty quickly, so this page tries to capture its progression. For the 'Life progress' counter I've used a life expectancy of 81.71 years.

scicomp_journals

Anonymous (anonymous@undisclosed.example.com) — 2020-05-31T22:13:12+00:00

Scientific Computing Journals This mostly serves as a list for myself, but perhaps it can also be useful for others. An excellent list of journals in which you can publish software can be found here. Mixed access * Computer Physics Communications (Elsevier) * Journal of Computational Physics (Elsevier) * Siam Journal on Scientific Computing

scicomp_netherlands

Anonymous (anonymous@undisclosed.example.com) — 2017-10-02T09:16:26+00:00

Computational Science links Netherlands UvA / VU (Amsterdam) * Computational Science (University of Amsterdam) TU Eindhoven * Centre for Analysis, Scientific computing and Applications (TU Eindhoven) * Center for Computational Energy Research (CCER) TU Delft * Institute for Computational Science and Engineering (TU Delft) TU Twente * Twente Centre for Scientific Computing * Multi-Scale Mechanics * Physics of Fluids * Multiscale Modeling and Simulation * Computational M…

start

Anonymous (anonymous@undisclosed.example.com) — 2019-05-06T09:39:26+00:00

By creation date * Postdoc fellowships in the Netherlands * The Old Rabbit * Becoming a computational scientist * Fortran programming material * Ideas for sustainability * Ideas for Fortran improvements * The progression of time * Computational Science links * Scientific Computing Journals * My setup * Reading a variable number of elements in Fortran * Life and video games * Videos * Variance of averaged measurements of unequal size * C vs Fortran for scientific computing

sustainability_ideas

Anonymous (anonymous@undisclosed.example.com) — 2020-05-31T22:10:43+00:00

Ideas for sustainability Behavior * Work less * Consume less * Travel less * Enjoy things that cost few resources, such as talking/hanging out, reading books, playing games Transportation For any type of fast transportation through earth's atmosphere, drag (air resistance) will be important. The drag force is roughly proportional to the velocity squared, the surface area of the moving object and the air density. So assuming we won't have

the_old_rabbit

Anonymous (anonymous@undisclosed.example.com) — 2019-11-10T16:29:29+00:00

The Old Rabbit A short story I wrote as a young kid.

thoughts

Anonymous (anonymous@undisclosed.example.com) — 2019-05-05T23:45:09+00:00

Life and video games I'd say life and video games are pretty similar: * It's nice to play with others * Typically, you want to get good at it * There are three main motives to actively participate: * To enjoy yourself now * To invest in future enjoyment

variance_uneq_measurements

Anonymous (anonymous@undisclosed.example.com) — 2015-11-19T10:43:19+00:00

Variance of averaged measurements of unequal size Suppose that we have a random variable $X$ that we can only take averaged samples from. This means we cannot directly obtain a sample $X_i$, but only a sample of the mean of $k$ $X_i$'s. To complicate things, $k$ varies uncontrollably with each measurement. How do we estimate the variance of the original variable $\mathrm{Var}(X)$$S_{k_i}$$k_i$$X$$k_i$$$\mathrm{Var}(S_{k_i}) = \langle(S_{k_i} - \langle S_{k_i} \rangle)^2\rangle = \langle(S_{k_i}…

videos

Anonymous (anonymous@undisclosed.example.com) — 2018-10-09T22:05:11+00:00

Videos So you can see me move and speak! * CWI Multiscale Dynamics group video * FOM Veldhoven 2014 * UvA Master's programme in computational science * Video abstract