List between two numbers – definine number of steps, not step size

April 20, 2022

I want to create a list between two numbers, like:

import numpy as np

np.arange(0,100,10)

Output:

array([ 0, 10, 20, 30, 40, 50, 60, 70, 80, 90])

But I dont want to define the size of the step, but the number of steps. If I define 3 steps, then I want to get this list:

array([ 0, 50, 100])

Or 4 steps:

array([0, 33, 66, 100])

And so on.

It doesn’t matter if I have to set 4 (for all values) or 2 (only for interpolated values) to get the last output or if I’m getting an array or a list. Also how it rounds/ceils doesn’t matter as well. It’s only about the logical to create such lists.

>Solution :

As mentioned in the comments, numpy.linspace returns evenly spaced numbers over a specified interval.

import numpy as np

n_steps = 3 
np.linspace(start=0, stop=100, num=n_steps)
array([  0.,  50., 100.])

n_steps = 4
np.linspace(start=0, stop=100, num=n_steps)
array([  0.        ,  33.33333333,  66.66666667, 100.        ])

Edit
If you are looking for integers, you can then cast to int data type:

import numpy as np

n_steps = 3 
np.linspace(start=0, stop=100, num=n_steps, dtype=int)
array([  0,  50, 100])

n_steps = 4
np.linspace(start=0, stop=100, num=n_steps, dtype=int)
array([  0,  33,  66, 100])