Numpy recarray.cumprod () function | python



numpy.recarray.cumprod() returns the cumulative product of array elements along a given axis.

Syntax: numpy.recarray.cumprod (axis = None, dtype = None, out = None)

Parameters:
axis: Axis along which the cumulative product is computed. The default is to compute the product of the flattened array.
dtype: Type of the returned array, as well as of the accumulator in which the elements are multiplied.
out: [ndarray, optional] A location into which the result is stored.
 – & gt; If provided, it must have a shape that the inputs broadcast to.
 – & gt; If not provided or None, a freshly-allocated array is returned.

Return: A new array holding the result is returned unless out is specified, in which case it is returned.

Code # 1:

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

 
# import numy as geek

import numpy as geek

 
# create an input array with two different fields

in_arr = 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 )])

print ( "Input array:" , in_arr)

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

rec_arr = in_arr.view (geek.recarray)

print ( "Record array of float:" , rec_arr.a)

print ( " Record array of int: " , rec_arr .b)

  
# using recarray.cumprod methods
# place an array of posts along axis 1

out_arr = rec_arr.a.cumprod ( axis = 1 )

print ( "Output array along axis 1:" , out_arr) 

 
# applying recarray.cumprod methods
# to an array of int records along the 0 axis

out_arr = rec_arr.b.cumprod (axis = 0 )

print ( "Output array along axis 0:" , out_arr) 

Output:

 Input array: [[(5., 2) (3., -4) (6., 9)] [(9., 1) (5., 4) (-12., -7)]] Record array of float: [[5. 3. 6. ] [9. 5. -12.]] Record array of int: [[2 -4 9] [1 4 -7]] Output array along axis 1: [[5. 15. 90.] [9. 45. -540.]] Output array along axis 0: [[2 -4 9] [2 -16 -63]]