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NumPy - ndarray.flat function



The NumPy ndarray.flat() is an array attribute and it is a 1-D iterator over the array.

Syntax

numpy.ndarray.flat

Parameters

No parameter is required.

Return Value

Returns a 1-D iterator over the array.

Example:

In the example below, ndarray.flat is used to access elements of an array.

import numpy as np

x = np.array([[10,20,30],
              [40,50,60]])
n = x.size

#displaying all elements using flat attribute
y1 = x.flat[0:n]
print("x.flat[0:n] =", y1)

#displaying 3rd element using flat attribute
y2 = x.flat[3]
print("x.flat[3] =", y2)

print()
#displaying all elements using flat attribute
#on transpose of the array
y3 = x.T.flat[0:n]
print("x.T.flat[0:n] =", y3)

#displaying 3rd element using flat attribute
#on transpose of the array
y4 = x.T.flat[3]
print("x.flat[3] =", y4)

The output of the above code will be:

x.flat[0:n] = [10 20 30 40 50 60]
x.flat[3] = 40

x.T.flat[0:n] = [10 40 20 50 30 60]
x.flat[3] = 50

Example:

The ndarray.flat attribute can be used to assign value to the array.

import numpy as np

x = np.array([[10,20,30],
              [40,50,60]])
y = np.array([[10,20,30],
              [40,50,60]])

#assign value to all elements
#of the array using flat attribute
x.flat = 10
print("x =")
print(x)

print()
#assign value to given elements 
#of the array using flat attribute
y.flat[[1, 2, 3]] = 5
print("y =")
print(y)

The output of the above code will be:

x =
[[10 10 10]
 [10 10 10]]

y =
[[10  5  5]
 [ 5 50 60]]

❮ NumPy - Array Manipulation

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