array matching

Jean-Michel Pichavant jeanmichel at sequans.com
Fri Apr 30 11:23:28 CEST 2010


Bill Jordan wrote:
> Hey guys,
>  
> I am sorry if this is not the right list to post some questions. I 
> have a simple question please and would appreciate some answers as I 
> am new to Python.
>  
> I have 2 D array: test = [[A,1],[B,2],[A,3][B,4]]
> I want to arrang this array in different arrays so each one will have 
> what is attached to. For example I want the output:
>  
> A =[1,3] and B=[2,4]
>  
> Thanks,
> Bill
>
Did you try anything before asking ? this is a pretty simple problem.

test = [['A',1],['B',2],['A',3], ['B',4]]

arranged ={} # dictionary containing the arranged arrays

for name, value in test: # you better be sure all arrays contain only 2 
elements
    if name in arranged:
        arranged[name].append(value)
    else:
        arranged[name] = [value]

print arranged
out: {'A': [1, 3], 'B': [2, 4]}

JM




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