Why I love Python: More rambling...

[Fernando Perez]

Alex Martelli wrote:

> Ville Vainio wrote:
>> Another aspect of motivation is accomplishment - a thing that might
>> make a C++ programmer proud of his achievement seems like a trivial 15
>> minute job for a Pythonista, and when that Pythonista is tasked w/ the
>> C++ job he doesn't get the kick from the accomplishment. And 6 hours
>> of debugging that "trivial" program doesn't help either.
> 
> Yep.  Managing to write even just "SPQR" with the marble and chisel
> without cracking the slab makes you proud (that Q is _so_ tricky!) --
> with a word processor, or pen and paper, you'd get no kick from the
> accomplishment.  And six hours of sandpapering and polishing that
> marble slab doesn't help either.

Data point (real world, from a few weeks ago): after spending ~2 weeks (spread
over a month) writing about 1400 lines of C++, debugging a nasty coredump, and
pounding the documentation, I had my 'fast' extension module finished for some
numerical work.  Great, sweaty and exhausted but all proud of myself, I turn
my attention to the problem of writing a unittest.  I decided to write it in
python, since I figured it would be easier, and an independent implementation
of the algorithm (simple one) should suffice, if tested with enough random
data.

Python code: 15 lines (no, it's NOT a typo: fifteen).  Time to write it: 10
minutes.

The sad part (to my ego, at least:)?  The python runs faster!  The C++ version
is now in the dustbin.  At least I learned a bunch about the STL and
templates.  The consolation...

Cheers,

f.

ps for those thinking: you must be an idiot of a C++ programmer. That may well
be true.  But still, there are reasons for the difference.  The C++ version
uses a heavily templated library for handling multidimensional arrays with a
bearable syntax, and g++ isn't the best compiler out there for that kind of
code.  The python version relies on Numeric.innerproduct(), which is very well
optimized, and tackles head-on the problem I was avoiding with the templates,
namely very annoying pointer manipulations for multidimensional tensors.  The
Numeric guys got their hands dirty, did it once RIGHT, and it works extremely
well.