Numpy recarray.dot () function | python

numpy.recarray.dot() returns the product of two arrays of records.

Syntax: numpy.recarray.dot (arr, out = None)

Parameters:
arr: array of the second record … 
out: [ndarray, optional] Location where the result is stored. 
– & gt; If provided, it should have the form to which the inputs are translated. 
– & gt; If not specified or No, the newly allocated array is returned.

Return: Returns a new array containing the result, unless out is specified, in which case it is returned.

Code # 1:

# Python program explaining
# numpy.recarray.dot () method

 
# import numy as geek

import numpy as geek

 
# create 2 input arrays with 2 different fields

in_arr1 = geek.array ([[( 5.0 , 2 ), ( 3.0 , - 4 ), ( 6.0 , 9 )],

[( 9.0 , 1 ), ( 5.0 , 4 ), ( - 12.0 , - 7 ) ]],

dtype = [( `a` , float ), ( ` b` , int )])

 

in_arr2 = geek.array ([[( 2.0 , 1 ), ( 4.0 , - 3 )],

  [( 8.0 , 3 ), ( 6.0 , 5 )],

[( 6.0 , - 5 ), ( - 5.0 , 4 )]],

dtype = [( `a ` , float ), ( `b` , int )])

 

print ( "1st Input array:" , in_arr1)

print ( " 2nd Input array: " , in_arr2)

 
# convert it to array of posts,
# using arr.view (np.recarray)

rec_arr1 = in_arr1.view (geek.recarray)

print ( "1st Record array of float:" , rec_arr1. a)

print ( "1st Record array of int: " , rec_arr1.b)

rec_arr2 = in_arr2.view (geek.recarray)

print ( "2nd Record array of float:" , rec_arr2.a)

print ( "2nd Record array of int:" , rec_arr2.b)

  
# applying recarray.dot methods
# between two arrays of floating point records

out_arr1 = rec_arr1.a.dot (rec_arr2.a)

print ( "Output float array :" , out_arr1) 

 
# using recarray.dot methods
# between two arrays of int records

out_arr1 = rec_arr1.b.dot (rec_arr2.b)

prin t ( "Output int array :" , out_arr1) 

Exit:

 1st Input array: [[ (5., 2) (3., -4) (6., 9)] [(9., 1) (5., 4) (-12., -7)]] 2nd Input array: [[( 2., 1) (4., -3)] [(8., 3) (6., 5)] [(6., -5) (-5., 4)]] 1st Record array of float: [[5. 3. 6.] [9. 5. -12.]] 1st Record array of int: [[2 -4 9] [1 4 -7]] 2nd Record array of float: [[2. 4 .] [8. 6.] [6. -5.]] 2nd Record array of int: [[1 -3] [3 5] [-5 4]] Output float array: [[70. 8.] [ -fourteen. 126.]] Output int array: [[-55 10] [48 -11]]