code optimization (calc PI)

[Michael]

Hmm..  thanks. I did this changes, but without any performance profits.


Matimus wrote:

> Using the '+' operator for string concatonation can be slow, especially
> when done many times in a loop.
> 
> 
>>   pi = pi + str("%04d" % int(e + d/a))  ## this should be fast?! I dont
> 
> 
> The accepted solution would be to make pi an array and append to the
> end...
> 
> pi = [] #create the array (empty)
> ...
> ...
> pi.append(str("%04d"%int(e+d/a))) # append to it
> 
> And when it is time to print the results do the following:
> 
> print "".join(pi)
> 
> It may look strange, but it is a common Python idiom. You might also
> look into an optimizer such as psycho: http://psyco.sourceforge.net/.
>