How to make exception for a number in the range of for loop in python

Question

In Python when I define a range for a variable, for example

for i in range(0,9):

but here I want to prevent i from taking a value of 7. How can I do this?

possible duplicate of How to conditionally skip number of iteration steps in a for loop in python? — BSMP
– BSMP, Commented May 30, 2015 at 3:01

Cleb · Accepted Answer · 2016-01-26 23:30:46Z

2

Depends on what exactly you want to do. If you just want to create a list you can simply do:

ignore=[2,7] #list of indices to be ignored
l = [ind for ind in xrange(9) if ind not in ignore]

which yields

[0, 1, 3, 4, 5, 6, 8]

You can also directly use these created indices in a for loop e.g. like this:

[ind**2 for ind in xrange(9) if ind not in ignore]

which gives you

[0, 1, 9, 16, 25, 36, 64]

or you apply a function

def someFunc(value):
    return value**3

[someFunc(ind) for ind in xrange(9) if ind not in ignore]

which yields

[0, 1, 27, 64, 125, 216, 512]

answered May 30, 2015 at 1:48

Cleb

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