# Compute the truth value of an array OR to another array element-wise based on conditions in Numpy

To compute the truth value of an array OR another array element-wise, use the numpy.logical_or() method in Python Numpy. Return value is either True or False. We have set conditions here as a parameter. Return value is the boolean result of the logical OR operation applied to the elements of x1 and x2; the shape is determined by broadcasting. This is a scalar if both x1 and x2 are scalars.

The out is a location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.

The condition is broadcast over the input. At locations where the condition is True, the out array will be set to the ufunc result. Elsewhere, the out array will retain its original value. Note that if an uninitialized out array is created via the default out=None, locations within it where the condition is False will remain uninitialized.

## Steps

At first, import the required library −

import numpy as np

Creating two 2D numpy array using the array() method. We have inserted elements. The True is considered value 1. The False is considered value 0 −

arr1 = np.array([[True, 8, 7], [13, False, 11]])
arr2 = np.array([[False, 9, True], [19, 25, 6]])

Display the arrays −

print("Array 1...", arr1)
print("Array 2...", arr2)

Get the type of the arrays −

print("Our Array 1 type...", arr1.dtype)
print("Our Array 2 type...", arr2.dtype)

Get the dimensions of the Arrays −

print("Our Array 1 Dimensions...",arr1.ndim)
print("Our Array 2 Dimensions...",arr2.ndim)

Get the shape of the Arrays −

print("Our Array 1 Shape...",arr1.shape)
print("Our Array 2 Shape...",arr2.shape)

To compute the truth value of an array OR another array element-wise, use the numpy.logical_or() method. Return value is either True or False. We have set conditions here −

print("Result (OR)...",np.logical_or(arr1 > 10, arr2 < 15))

## Example

import numpy as np

# Creating two 2D numpy array using the array() method
# We have inserted elements
# The True is considered value 1
# The False is considered value 0
arr1 = np.array([[True, 8, 7], [13, False, 11]])
arr2 = np.array([[False, 9, True], [19, 25, 6]])

# Display the arrays
print("Array 1...", arr1)
print("Array 2...", arr2)

# Get the type of the arrays
print("Our Array 1 type...", arr1.dtype)
print("Our Array 2 type...", arr2.dtype)

# Get the dimensions of the Arrays
print("Our Array 1 Dimensions...",arr1.ndim)
print("Our Array 2 Dimensions...",arr2.ndim)

# Get the shape of the Arrays
print("Our Array 1 Shape...",arr1.shape)
print("Our Array 2 Shape...",arr2.shape)

# To compute the truth value of an array OR another array elementwise, use the numpy.logical_or() method in Python Numpy
# Return value is either True or False
# We have set conditions here
print("Result (OR)...",np.logical_or(arr1 > 10, arr2 < 15))

## Output

Array 1...
[[ 1 8 7]
[13 0 11]]

Array 2...
[[ 0 9 1]
[19 25 6]]

Our Array 1 type...
int64

Our Array 2 type...
int64

Our Array 1 Dimensions...
2

Our Array 2 Dimensions...
2

Our Array 1 Shape...
(2, 3)

Our Array 2 Shape...
(2, 3)

Result (OR)...
[[ True True True]
[ True False True]]

Updated on: 08-Feb-2022

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