find index of value in array python code example

Example 1: python find index by value

>>> ["foo", "bar", "baz"].index("bar")
1

Example 2: find an index of an item in a list python

#Example List
list = ['apples', 'bannas', 'grapes']
#Use Known Entites In The List To Find The Index Of An Unknown Object
Index_Number_For_Bannas = list.index('apples')
#Print The Object
print(list[Index_Number_For_Bannas])

Example 3: python get index and value from list

test = [ 'test 1', 'test 2', 'test 3' ]
for index, value in enumerate( test ):
  print( index, value )

Example 4: numpy find index of matching values

import numpy as np
# init arrays
a = np.array([1,2,3,2,3,4,3,4,5,6])
b = np.array([7,2,10,2,7,4,9,4,9,8])

#using enumerate, list comprehension and set
print([key for key, val in enumerate(a) if val in set(b)])
# output
# [1, 3, 5, 7]