NumPy builds on (and is a successor to) the successful Numeric array object. Its goal is to create the corner-stone for a useful environment for scientific computing. NumPy provides two fundamental objects: an N-dimensional array object (ndarray) and a universal function object (ufunc). In this post we are going to discuss ways in which we can find the length of each string element in the given numpy array. Problem #1 : Given a numpy array whose underlying data is of string type. Find the length of each element in the given object. Solution : We are going to use numpy.vectorize() function to find the length of each element in the given numpy array object.
# importing the numpy library as np import numpy as np
# Create a numpy array arr = np.array([ 'New York' , 'Lisbon' , 'Beijing' , 'Quebec' ])
# Print the array print (arr)
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Output :
# Use vectorize function of numpy length_checker = np.vectorize( len )
# Find the length of each element arr_len = length_checker(arr)
# Print the length of each element print (arr_len)
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Output :
# importing the numpy library as np import numpy as np
# Create a numpy array arr = np.array([ 'New York' , 'Lisbon' , 'Beijing' , 'Quebec' ])
# Print the array print (arr)
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Output :
# Find the length of each element arr_len = [ len (i) for i in arr]
# Print the length of each element print (arr_len)
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Output :
One additional approach to finding the length of each element in a NumPy array is to use the NumPy function numpy.char.str_len. This function takes a NumPy array of strings as input and returns an array of the lengths of each string. For example:
import numpy as np
# Create a numpy array arr = np.array([ 'New York' , 'Lisbon' , 'Beijing' , 'Quebec' ])
# Find the length of each element arr_len = np.char.str_len(arr)
# Print the length of each element print (arr_len)
#This code is contributed by Edula Vinay Kumar Reddy |
This will output: [8 7 7 6] (This code wont work in gfg compiler , install numpy in your local compiler then check )