numpy.index() in Python
Last Updated :
28 Nov, 2018
Improve
numpy.core.defchararray.index(arr, substring, start=0, end=None): Finds the lowest index of the sub-string in the specified range But if substring is not found, it raises ValueError.
Parameters: arr : array-like or string to be searched. substring : substring to search for. start, end : [int, optional] Range to search in. Returns : An integer array with the lowest index of found sub-string, raises ValueError if substring is not found.Code #1:
# Python Program illustrating
# numpy.char.index() method
import numpy as np
arr = ['this is geeks for geek']
print ("arr : ", arr)
print ("\nindex of 'geeks' : ", np.char.index(arr, 'geeks'))
arr : ['this is geeks for geek'] index of 'geeks' : [8]Code #2:
# Python Program illustrating
# numpy.char.index() method
import numpy as np
arr = ['this is geeks for geek']
print ("\nindex of 'geeks' : ", np.char.index(arr, 'geeks', start = 2))
print ("\nindex of 'geeks' : ", np.char.index(arr, 'geeks', start = 10))
print ("\nindex of 'geek' : ", np.char.index(arr, 'geek', start = 10))
index of 'geeks' : [8] ValueError: substring not found index of 'geek' : [18]
