numpy.power(arr1, arr2, out = None, where = True, casting = ‘same_kind’, order = ‘K’, dtype = None) :
Array element from first array is raised to the power of element from second element(all happens element-wise). Both arr1 and arr2 must have same shape and each element in arr1 must be raised to corresponding +ve value from arr2; otherwise it will raise a ValueError.
Parameters :
arr1 : [array_like]Input array or object which works as base. arr2 : [array_like]Input array or object which works as exponent. out : [ndarray, optional]Output array with same dimensions as Input array, placed with result. **kwargs : Allows you to pass keyword variable length of argument to a function. It is used when we want to handle named argument in a function. where : [array_like, optional]True value means to calculate the universal functions(ufunc) at that position, False value means to leave the value in the output alone.
Return :
An array with elements of arr1 raised to exponents in arr2
Code 1 : arr1 raised to arr2
# Python program explaining # power() function import numpy as np # input_array arr1 = [ 2 , 2 , 2 , 2 , 2 ] arr2 = [ 2 , 3 , 4 , 5 , 6 ] print ( "arr1 : " , arr1) print ( "arr1 : " , arr2) # output_array out = np.power(arr1, arr2) print ( "\nOutput array : " , out) |
Output :
arr1 : [2, 2, 2, 2, 2] arr2 : [2, 3, 4, 5, 6] Output array : [ 4 8 16 32 64]
Code 2 : elements of arr1 raised to exponent 2
# Python program explaining # power() function import numpy as np # input_array arr1 = np.arange( 8 ) exponent = 2 print ( "arr1 : " , arr1) # output_array out = np.power(arr1, exponent) print ( "\nOutput array : " , out) |
Output :
arr1 : [0 1 2 3 4 5 6 7] Output array : [ 0 1 4 9 16 25 36 49]
Code 3 : Error if arr2 has -ve elements
# Python program explaining # power() function import numpy as np # input_array arr1 = [ 2 , 2 , 2 , 2 , 2 ] arr2 = [ 2 , - 3 , 4 , - 5 , 6 ] print ( "arr1 : " , arr1) print ( "arr2 : " , arr2) # output_array out = np.power(arr1, arr2) print ( "\nOutput array : " , out) |
Output :
arr1 : [2, 2, 2, 2, 2] arr2 : [2, -3, 4, -5, 6] ValueError: Integers to negative integer powers are not allowed.
References :
https://docs.scipy.org/doc/numpy-1.13.0/reference/generated/numpy.power.html#numpy.power
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