Skip to content
Related Articles

Related Articles

Improve Article

numpy.index() in Python

  • Last Updated : 28 Nov, 2018
Geek Week

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'))

Output:



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))

Output:

index of 'geeks' : [8]
ValueError: substring not found
index of 'geek' : [18]

 Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.  

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning – Basic Level Course




My Personal Notes arrow_drop_up
Recommended Articles
Page :