[Numpy-discussion] loop through values in a array and find maximum as looping

[Derek Homeier]

On 07.12.2011, at 5:54AM, questions anon wrote:

> sorry the 'all_TSFC' is for my other check of maximum using concatenate and N.max, I know that works so I am comparing it to this method. The only reason I need another method is for memory error issues. 
> I like the code I have written so far as it makes sense to me. I can't get the extra examples I have been given to work and that is most likely because I don't understand them, these are the errors I get :
> 
> Traceback (most recent call last):
>   File "d:\plot_summarystats\test_plot_remove_memoryerror_max.py", line 46, in <module>
>     N.maximum(a,TSFC,out=a)
> ValueError: non-broadcastable output operand with shape (106,193) doesn't match the broadcast shape (721,106,193)
> 
> and
> 
OK, then it seems we did not indeed grasp the entire scope of the problem - 
since you have initialised a from the previous array TSFC (not from TSFC[0]?!), this can 
only mean the arrays read in come in different shapes? I don't quite understand how the 
previous version did not raise an error then; but if you only want the (106,193)-subarray 
you have indeed to keep the loop 
           for b in TSFC[:]:
                N.maximum(a,b,out=a)

But you would have to find some way to distinguish between ndim=2 and ndim=3 input, 
if really both can occur...
> 
> Traceback (most recent call last):
>   File "d:\plot_summarystats\test_plot_remove_memoryerror_max.py", line 45, in <module>
>     if not instance(a, N.ndarray):
> NameError: name 'instance' is not defined
> 
Sorry, typing error (or devious auto-correct?) - this should be 'isinstance()'

Cheers,
						Derek