python vs d

[bytedruid via Digitalmars-d]

On Thursday, 24 April 2014 at 06:38:42 UTC, Suliman wrote:
> I am following discussions about GC and some other 'critical' 
> improves in D language for a long time. I see a lot of 
> arguments and heaps of code, that often hard to understand (for 
> example Templates) even more complicated to use it.
>
> I like D, but more and more I am playing with Python, and 
> understanding it's philosophy. And I like it because it's do 
> not have any overhead like C++. It's clean any easy to 
> understanding. As result it's harder to write bad code in it.
>
> Does anybody make tests of speed most common algorithm in D and 
> Python. I am trying to understand which project better to start 
> in Python and which in D.

I'm completely new to D, but have been writing in python for 
quite a while.  Python is a very good language but it can be 
slow.  I've noticed that anything involving bit shifting is very 
slow.

On one project I had a CRC algorithm in a python program that had 
to read a 2 megabit/sec datastream, calculate/compare CRC's and 
write data to disk files based on encoded times.  The calculation 
involved bit shifting and the program couldn't keep up with the 
input stream at 96% CPU utilization.  I implemented the CRC 
calculation in C (with almost no change to the algorithm), and 
added a python binding, leaving the rest of the python program 
unchanged.  CPU utilization dropped to 4.5% and I was able to 
keep up with the input stream, no problem.

In general I guess that anytime you need native performance write 
the program in D.  If it doesn't matter one way or the other 
write in D because you can deliver a binary with no dependency on 
an interpreter.  But if you know that the python interpreter will 
be available on the target system, and you need to make use of 
the extensive python standard library, and your program isn't 
multi-threaded, then use Python.