get an array variable in python

Question

can I do this in a loop, by producing the file name from the name of the array to store ?

ab = array.array('B', map( operator.xor, a, b ) )
f1 = open('ab', 'wb')
ab.tofile(f1)
f1.close
ac = array.array('B', map( operator.xor, a, c ) )
f1 = open('ac', 'wb')
ac.tofile(f1)
f1.close
ad = array.array('B', map( operator.xor, a, d ) )
f1 = open('ad', 'wb')
ad.tofile(f1)
f1.close
ae = array.array('B', map( operator.xor, a, e ) )
f1 = open('ae', 'wb')
ae.tofile(f1)
f1.close
af = array.array('B', map( operator.xor, a, f ) )
f1 = open('af', 'wb')
af.tofile(f1)
f1.close

thank you for any help!

John La Rooy · Answer 1 · 2010-03-10T22:01:15.723

2

Assuming you are storing all the intermediate arrays for a reason.

A={}
for v,x in zip((b,c,d,e,f),'bcdef'):
    fname = 'a'+x
    A[fname] = (array.array('B', map( operator.xor, a, v ) ))
    f1 = open(fname, 'wb')
    A[fname].tofile(f1)
    f1.close

Or something like this should work too

A={}
for x in 'bcdef':
    fname = 'a'+x
    A[fname] = (array.array('B', map(a.__xor__, vars()[x] ) ))
    f1 = open(fname, 'wb')
    A[fname].tofile(f1)
    f1.close

edited Mar 10 '10 at 22:01

answered Mar 10 '10 at 21:23

John La Rooy

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Doesn't this just compute `map(operator.xor, a, b)` repeatedly? – Mark Dickinson Mar 10 '10 at 21:36
@Mark Dickinson, yes it was. I fixed it now :) – John La Rooy Mar 10 '10 at 22:02

score 1 · Accepted Answer · answered Mar 10 '10 at 21:27

1

One way is to have a,b,c,d,e,f in a dict. Then you'd just do something like:

for x in 'bcdef':
    t = array.array('B', map( operator.xor, mydict['a'], mydict[x] ) )
    f1 = open(''.join('a',x),'wb')
    t.tofile(f1)
    f1.close()

answered Mar 10 '10 at 21:27

Justin Peel

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They are in a dict -- it's called *locals()* :) – Ian Clelland Mar 10 '10 at 21:34
1

@Ian Yes, but some people don't like to use that because it is kind of a hack. – Justin Peel Mar 10 '10 at 21:50
The way I was doing it was to have mydict['a'] return the array a. You can use locals() by just replacing mydict with locals(). – Justin Peel Mar 10 '10 at 22:02

get an array variable in python

2 Answers2