python - Values of variables inside a for-loop -



python - Values of variables inside a for-loop -

i have array a defined outside for-loop. b variable assigned equal a within loop. alter values of b within loop alters a. why/how happen?

>>> import numpy np >>> = np.asarray(range(10)) >>> in range(5,7): b = #assign b equal b[b<i]=0 #alter b b[b>=i]=1 print

output:

[0 0 0 0 0 1 1 1 1 1] #unexpected!! [0 0 0 0 0 0 0 0 0 0]

why a altered when don't explicitly so?

because when b = a reference gets copied. both a , b point same object.

if want create re-create of a need example:

import re-create ... b = copy.deepcopy(a)

python python-2.7 numpy

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