# Return the absolute value of a masked Array in NumPy

NumpyServer Side ProgrammingProgramming

To return the absolute value of a masked Array, use the ma.MaskedArray.__abs__() method. If the element is negative, the abs() method negates it and returns. A masked array is the combination of a standard numpy.ndarray and a mask. A mask is either nomask, indicating that no value of the associated array is invalid, or an array of booleans that determines for each element of the associated array whether the value is valid or not.

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## 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([[55, 85, -68, 84], [67, -33, -39, -53], [29, 88, -51, 37], [-56, -45, 67, 85]])
print("Array...\n", arr)
print("\nArray type...\n", arr.dtype)

Get the dimensions of the Array −

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

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

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

Get the dimensions of the Masked Array −

print("\nOur Masked Array Dimensions...\n",maskArr.ndim)

Get the shape of the Masked Array −

print("\nOur Masked Array Shape...\n",maskArr.shape)

Get the number of elements of the Masked Array −

print("\nElements in the Masked Array...\n",maskArr.size)


To return the absolute value of a masked Array, use the ma.MaskedArray.__abs__() method. If the element is negative, the abs() method negates it and returns. If the element is positive, the abs() method returns the same value −

print("\nReturning the absolute value of the elements of a masked array...\n", maskArr.__abs__())

## 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, -68, 84], [67, -33, -39, -53], [29, 88, -51, 37], [-56, -45, 67, 85]])
print("Array...\n", arr)
print("\nArray type...\n", arr.dtype)

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

# Create a masked array and mask some of them as invalid
maskArr = ma.masked_array(arr, mask =[[1, 1, 0, 0], [ 0, 0, 1, 0], [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 return the absolute value of a masked Array, use the ma.MaskedArray.__abs__() method
# If the element is negative, the abs() method negates it and returns
# If the element is positive, the abs() method returns the same value
print("\nReturning the absolute value of the elements of a masked array...\n",
maskArr.__abs__())

## Output

Array...
[[ 55 85 -68 84]
[ 67 -33 -39 -53]
[ 29 88 -51 37]
[-56 -45 67 85]]

Array type...
int64

Array Dimensions...
2

[[-- -- -68 84]
[67 -33 -- -53]
[29 88 -51 --]
[-56 -- 67 85]]

int64

2

[56 -- 67 85]]