# Repeat elements of a masked array along given axis in NumPy

To repeat elements of a masked array, use the ma.MaskedArray.repeat() method in Numpy. The "repeats" parameter sets the number of repetitions for each element. The repeats is broadcasted to fit the shape. The "axis" parameter is the axis along which to repeat values.

The method returns the output array which has the same shape as a, except along the given axis. The axis is the axis along which to repeat values. By default, use the flattened input array, and return a flat output array.

## Steps

At first, import the required library −

import numpy as np
import numpy.ma as ma

Create an array with int elements using the numpy.array() method −

arr = np.array([[49, 85, 45], [67, 33, 59]])
print("Array...", arr)
print("Array type...", arr.dtype)

Get the dimensions of the Array −

print("Array Dimensions...",arr.ndim)


Create a masked array and mask some of them as invalid −

maskArr = ma.masked_array(arr, mask =[[0, 0, 1], [ 0, 1, 0]])
print("Our Masked Array type...", maskArr.dtype)

Get the dimensions of the Masked Array −

print("Our Masked Array Dimensions...",maskArr.ndim)


Get the shape of the Masked Array −

print("Our Masked Array Shape...",maskArr.shape)

Get the number of elements of the Masked Array −

print("Elements in the Masked Array...",maskArr.size)


To repeat elements of a masked array, use the ma.MaskedArray.repeat() method in Numpy. The "repeats" parameter sets the number of repetitions for each element. The repeats is broadcasted to fit the shape. The "axis" parameter is the axis along which to repeat values. By default, use the flattened input array, and return a flat output array −

print("Result...",maskArr.repeat(3, axis = 0))

## Example

import numpy as np
import numpy.ma as ma

# Create an array with int elements using the numpy.array() method
arr = np.array([[55, 85, 59, 77], [67, 33, 39, 57], [29, 88, 51, 37],
[56, 45, 99, 85]])
print("Array...", arr)
print("Array type...", arr.dtype)

# Get the dimensions of the Array
print("Array Dimensions...",arr.ndim)

# Create a masked array and mask some of them as invalid
[0, 0, 0, 1], [0, 1, 0, 0]])

# Get the dimensions of the Masked Array

# Get the shape of the Masked Array

# Get the number of elements of the Masked Array

# To repeat elements of a masked array, use the ma.MaskedArray.repeat() method in Numpy
# The "repeats" parameter sets the number of repetitions for each element.
# The repeats is broadcasted to fit the shape.
# The "axis" parameter is the axis along which to repeat values.
# By default, use the flattened input array, and return a flat output array.
print("Result...",maskArr.repeat(3, axis = 0))

## Output

Array...
[[55 85 59 77]
[67 33 39 57]
[29 88 51 37]
[56 45 99 85]]

Array type...
int64

Array Dimensions...
2

[[-- -- 59 77]
[67 33 -- 57]
[29 88 51 --]
[56 -- 99 85]]

int64

2

(4, 4)

16

Result...
[[-- -- 59 77]
[-- -- 59 77]
[-- -- 59 77]
[67 33 -- 57]
[67 33 -- 57]
[67 33 -- 57]
[29 88 51 --]
[29 88 51 --]
[29 88 51 --]
[56 -- 99 85]
[56 -- 99 85]
[56 -- 99 85]]

Updated on: 04-Feb-2022

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