The Sleef library is an optimised library for the calculation of mathematical functions: the trigonometric functions(sin, cos, tan, sincos), inverse trigonometric functions(asin, acos, atan, atan2), exponential and logarithmic functions(exp, log, pow, exp2, exp10, expm1, log10, log1p), hyperbolic/inverse hyperbolic functions(sinh, cosh, … Continue reading
The compiler gfortran is able to automatically vectorize part of the code. The flag “–ftree-vectorize” enable the auto-vectorization and some diagnostics are written on the screen at compile time with the flag “-ftree-vectorizer-verbose=x” (x is a number from 1 to … Continue reading
I previously talked the use of optimised trigonometric function through the use of the acml library. Trigonometric functions are coded in hardware through the x87 extension but it works on 80bits which is not necessary all the time. So software … Continue reading
New subject for this post. Since my new position at the crm2 in Nancy, I am working with optics. We set up an experiment on interferences and optical diffraction for demonstration. I am looking for a free open source software … Continue reading
Part of a study on the standard deviation of the electron density using Monte Carlo simulations, I was needing a fast way to calculate structure factors. I achieve this goal a while ago but I continued to improve things each … Continue reading
Vectorization is a nice concept in optimisation. It allows simulaneous calculations using special units in the processor. It is working only on special cases. I tried to apply to structure factors calculations. Fortran does not allow you to write vector … Continue reading
A bug happened on the last December release of platon-nightly which was dated from 2012 instead of 2011. I forced the update (I increase the epoch tag) for the January release so that it will updated as usual.
I changed a few things in the settings of the blog. You have to be logged in to comment. No worry, you don’t need to create an account on Debroglie you can just login via facebook, twitter, google or linkedin. … Continue reading
Small reveiw and feelings about a few graphical libraries: gnuplot, matplotlib, pgplot, plplot, dislin and R. Continue reading
This post is the continuation of the previous one on: CPU starvation I needed to rewrite a part of the code and it was a good opportunity to change the algorithm of the variance calculation. I was using the naive … Continue reading