NumPy: multiply() function

numpy.core.defchararray.multiply() function

Return (a * i), that is string multiple concatenation, element-wise.
Values in i of less than 0 are treated as 0 (which yields an empty string).

Version: 1.15.0

Syntax:

numpy.core.defchararray.multiply(a, i)

Parameter:

Return value:

out : ndarray - Output array of str or unicode, depending on input types

Note:

The 'chararray' class exists for backwards compatibility with Numarray, it is not recommended for new development. Starting from numpy 1.4, if one needs arrays of strings, it is recommended to use arrays of 'dtype' 'object_', 'string_' or 'unicode_', and use the free functions in the 'numpy.char' module for fast vectorized string operations.

Some methods will only be available if the corresponding string method is available in your version of Python.

The preferred alias for 'defchararray' is 'numpy.char'.

Example-1: numpy.multiply() function

import numpy as np  
a1 = ['aaa', 'bbb', 'ccc'] 
a2 = ['ppp', 'qqq', 'rrr'] 
print("\na1 : ", a1) 
print("\na2 : ", a2) 
print("\na1 : ", np.char.multiply(a1, 2)) 
print ("\na1 : ", np.char.multiply(a1, [2, 4, 3])) 
print ("\na2 : ", np.char.multiply(a2, 3)) 

Output:

a1 :  ['aaa', 'bbb', 'ccc']

a2 :  ['ppp', 'qqq', 'rrr']

a1 :  ['aaaaaa' 'bbbbbb' 'cccccc']

a1 :  ['aaaaaa' 'bbbbbbbbbbbb' 'ccccccccc']

a2 :  ['ppppppppp' 'qqqqqqqqq' 'rrrrrrrrr']

Pictorial Presentation:

Pictorial Presentation:

Pictorial Presentation:

Example-2: numpy.multiply() function

import numpy as np  
arr1 = 'Python'
arr2 = 'NumPy Tutorial '
print ("\narr1 : ", np.char.multiply(arr1, 2)) 
print ("\narr2 : ", np.char.multiply(arr2, 4)) 

Output:

arr1 :  PythonPython

arr2 :  NumPy Tutorial NumPy Tutorial NumPy Tutorial NumPy Tutorial 

Python - NumPy Code Editor:

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