Comparison-Programming-Languages-Economics

Compare the implementation of a simple numerical program in Haskell https://github.com/jmoy/avb-econ-hs/blob/f6d65af480c99045573... to that in Julia https://github.com/jesusfv/Comparison-Programming-Languages-... Despite the Haskell program using the elegant facilities provided by REPA, the fact that mutable part (the `writePolicy`) has to be written in a different style than the pure parts since it is a monadic action seems cumbersome to me.

10x speedup (same algorithms, same architecture) replacing Java with C++ is not possible (~2x at max). One of the latest benchmarks I've seen is "Comparison of Programming Languages in Economics" [1] for code without any IO just number crunching, has a 1.91 to 2.69 speedup of using C++ compared to Java. So any code involving IO is going to be slower. Replacing bad Java code with excellent machine aligned C++ a 10x speedup is possible. [1] https://github.com/jesusfv/Comparison-Programming-Languages-...

github: https://github.com/jesusfv/Comparison-Programming-Languages-...

Another interesting comparison from the github repo[1] is the proportions of lines that it took in each language. [1] https://github.com/jesusfv/Comparison-Programming-Languages-...

I almost gasped when I saw that their R code[1] does the bulk of its computations inside a while(...for(...for(...for(...if(...){...}else{...})))) block, instead of using functionals like apply and 'vectorized' operations like ifelse. If this criticism seems harsh, compare the authors' R code to Hadley Wickham's advice at http://adv-r.had.co.nz/Profiling.html -- or just search Google for "speed-up loops in R". -- [1] https://github.com/jesusfv/Comparison-Programming-Languages-...

Their code is on github [1]. I am a C++ programmer so I'm happy that C++ came out on top, but the comparison is obviously flawed (as these sorts of comparisons always are). The problem is that the implementers don't have the same level of skill in each language and who knows how much time they spent analyzing and refining each version. See Russ Cox's response [2] to a Google paper [3] of a similar nature comparing C++, Go, Java, Scala for an example of a similar boondoggle. The R code, for instance, is obviously unidiomatic. If you have a four levels deep nested loop in R, you're doing it wrong, and it's taking every ounce of willpower to keep from spending the rest of the afternoon trying to fix up their code and make it faster. 1. https://github.com/jesusfv/Comparison-Programming-Languages-... 2. http://blog.golang.org/profiling-go-prog

GitHub repo and PDF here: https://github.com/jesusfv/Comparison-Programming-Languages-...