How to convert a float array to an integer array in python ?

Examples of how to convert a float array to an integer array in python:

Using the numpy function astype

To convert a float array to an integer array in python, a solution is to use astype, example:

>>> import numpy as np
>>> A = np.array((0.4, 1.6, 2.1, -3.7, 2.9))
>>> A
array([ 0.4,  1.6,  2.1, -3.7,  2.9])
>>> A = A.astype(int)
>>> A
array([ 0,  1,  2, -3,  2])

Round the numbers before converting them in integer

It is also possible to round the numbers and after convert them to integer using the numpy function around

>>> import numpy as np
>>> A = np.array((0.4, 1.6, 2.1, -3.7, 2.9))
>>> A
array([ 0.4,  1.6,  2.1, -3.7,  2.9])
>>> A = np.around(A)
>>> A
array([ 0.,  2.,  2., -4.,  3.])
>>> A = A.astype(int)
>>> A
array([ 0,  2,  2, -4,  3])

Note: work also with the function rint, example

>>> import numpy as np
>>> A = np.array((0.4, 1.6, 2.1, -3.7, 2.9))
>>> A
array([ 0.4,  1.6,  2.1, -3.7,  2.9])
>>> A = np.rint(A)
>>> A
array([ 0.,  2.,  2., -4.,  3.])
>>> A = A.astype(int)
>>> A
array([ 0,  2,  2, -4,  3])

Truncate the numbers first

>>> import numpy as np
>>> A = np.array((0.4, 1.6, 2.1, -3.7, 2.9))
>>> A
array([ 0.4,  1.6,  2.1, -3.7,  2.9])
>>> A = np.trunc(A)
>>> A
array([ 0.,  1.,  2., -3.,  2.])
>>> A = A.astype(int)
>>> A
array([ 0,  1,  2, -3,  2])

Round to the nearest bigger integer

>>> import numpy as np
>>> A = np.array((0.4, 1.6, 2.1, -3.7, 2.9))
>>> A
array([ 0.4,  1.6,  2.1, -3.7,  2.9])
>>> A = np.ceil(A)
>>> A
array([ 1.,  2.,  3., -3.,  3.])
>>> A = A.astype(int)
>>> A
array([ 1,  2,  3, -3,  3])

Round to the nearest smaller integer

>>> import numpy as np
>>> A = np.array((0.4, 1.6, 2.1, -3.7, 2.9))
>>> A
array([ 0.4,  1.6,  2.1, -3.7,  2.9])
>>> A = np.floor(A)
>>> A
array([ 0.,  1.,  2., -4.,  2.])
>>> A = A.astype(int)
>>> A
array([ 0,  1,  2, -4,  2])

References