numpy string operations | ljust() function

numpy.core.defchararray.ljust(arr, width, fillchar=' ') is another function for doing string operations in numpy. It returns an array with the elements of arr left-justified in a string of length width. It fills remaining space of each array element using fillchr parameter. If fillchr is not passed then it fills remaining spaces with blank space.

Parameters:
arr : array_like of str or unicode.Input array.
width : The final width of the each string .
fillchar : The character to fill in remaining space.

Returns : Output array of str or unicode, depending on input type.

Code #1 :

# Python program explaining
# numpy.char.ljust() method

# importing numpy
import numpy as geek

# input array
in_arr = geek.array(['Numpy', 'Python', 'Pandas'])
print ("Input array : ", in_arr)

# setting the width of each string to 8
width = 8

# output array when fillchar is not passed
out_arr = geek.char.ljust(in_arr, width)
print ("Output left justified array: ", out_arr)

Output:

Input array :  ['Numpy' 'Python' 'Pandas']
Output left justified array:  ['Numpy   ' 'Python  ' 'Pandas  ']

Code #2 :

# Python program explaining
# numpy.char.ljust() method

# importing numpy
import numpy as geek

# input array
in_arr = geek.array(['Numpy', 'Python', 'Pandas'])
print ("Input array : ", in_arr)

# setting the width of each string to 8
width = 8

# output array
out_arr = geek.char.ljust(in_arr, width, fillchar ='*')
print ("Output left justified array: ", out_arr)

Output:

Input array :  ['Numpy' 'Python' 'Pandas']
Output left justified array:  ['Numpy***' 'Python**' 'Pandas**']

Code #3 :

# Python program explaining
# numpy.char.ljust() method

# importing numpy
import numpy as geek

# input array
in_arr = geek.array(['1', '11', '111'])
print ("Input array : ", in_arr)

# setting the width of each string to 5
width = 5

# output array
out_arr = geek.char.ljust(in_arr, width, fillchar ='-')
print ("Output left justified array: ", out_arr)

Output:

Input array :  ['1' '11' '111']
Output left justified array:  ['1----' '11---' '111--']