Making a list of evenly spaced numbers in a certain range in python

Question

What is a pythonic way of making list of arbitrary length containing evenly spaced numbers (not just whole integers) between given bounds? For instance:

my_func(0,5,10) # ( lower_bound , upper_bound , length ) # [ 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5 ]  

Note the Range() function only deals with integers. And this:

def my_func(low,up,leng):     list = []     step = (up - low) / float(leng)     for i in range(leng):         list.append(low)         low = low + step     return list 

seems too complicated. Any ideas?

Answer 1

Given numpy, you could use linspace:

Including the right endpoint (5):

In [46]: import numpy as np In [47]: np.linspace(0,5,10) Out[47]:  array([ 0.        ,  0.55555556,  1.11111111,  1.66666667,  2.22222222,         2.77777778,  3.33333333,  3.88888889,  4.44444444,  5.        ]) 

Excluding the right endpoint:

In [48]: np.linspace(0,5,10,endpoint=False) Out[48]: array([ 0. ,  0.5,  1. ,  1.5,  2. ,  2.5,  3. ,  3.5,  4. ,  4.5]) 

Answer 2

You can use the following approach:

[lower + x*(upper-lower)/length for x in range(length)] 

lower and/or upper must be assigned as floats for this approach to work.