What is numpy.subtract() in Python?
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Python’s numpy.subtract() method subtracts two arrays element-wise.
Syntax
numpy.subtract() is declared as shown below:
numpy.subtract(x1, x2, /, out=None, *, where=True, casting='same_kind', order='K', dtype=None, subok=True[, signature, extobj]) = <ufunc 'subtract'>
A universal function (ufunc) is a function that operates on ndarrays in an element-by-element fashion. The
subtract()method is a universal function.
Parameters
The numpy.subtract() method takes the following compulsory parameters:
x1andx2[array-like] - arrays that need to be subtracted. If theshape the shape of an array is the number of elements in each dimension x1andx2is different, they must be broadcastable to a common shape for representing the output.
The numpy.subtract() method takes the following optional parameters:
Parameter | Description |
out | Represents the location into which the output of the method is stored. If not provided or None, a freshly-allocated array is returned. |
where | True value indicates that a universal function should be calculated at this position. |
casting | Controls the type of datacasting that should occur. The same_kind option indicates that safe casting or casting within the same kind should take place. |
order | Controls the memory layout order of the output function. The option K means reading the elements in the order they occur in memory. |
dtype | Represents the desired data type of the array. |
subok | Decides if subclasses should be made or not. If True, subclasses will be passed through. |
Return value
numpy.subtract() returns the difference of the two arrays element-wise. The return type is either ndarray or scalar depending on the input type.
Examples
The examples below show the different ways numpy.subtract() is used in Python.
Subtraction of two numbers
The code below outputs the difference of two numbers, 17.5 and 12. The result is shown below:
import numpy as npa = 17.5b = 12result = np.subtract(a,b)print (result)
Subtraction of two arrays
The example below shows the result of subtracting two arrays arr1 and arr2:
import numpy as nparr1 = np.array([20,30,40])arr2 = np.array([2,3,4])result = np.subtract(arr1,arr2)print (result)
The example below shows the result of subtracting two arrays arr3 and arr4:
import numpy as nparr3 = np.array([[20,30,40], [-2,-3,-4]])arr4 = np.array([[-2,-3,-4], [30,40,50]])result = np.subtract(arr3,arr4)print (result)
