Get the Tuple of bytes to step in each dimension when traversing in Numpy

NumpyServer Side ProgrammingProgramming

To get the Tuple of bytes to step in each dimension when traversing an array, use the ma.MaskedArray.strides attribute in Numpy. The byte offset of element (i[0], i[1], ..., i[n]) in an array a is −

offset = sum(np.array(i) * a.strides)

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.

Steps

At first, import the required library −

import numpy as np
import numpy.ma as ma

Create an array using the numpy.array() method −

arr = np.array([[35, 85], [67, 33]])
print("Array...\n", arr)
print("\nArray type...\n", arr.dtype)
print("\nArray itemsize...\n", arr.itemsize)

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

Get the itemsize of the Masked Array −

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

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)

Get the Tuple of bytes to step in each dimension when traversing an array, use the ma.MaskedArray.strides attribute in Numpy

print("\nStrides...\n",maskArr.strides)

Example

import numpy as np
import numpy.ma as ma

arr = np.array([[35, 85], [67, 33]])
print("Array...\n", arr)
print("\nArray type...\n", arr.dtype)
print("\nArray itemsize...\n", arr.itemsize)

# 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 =[[0, 0], [ 0, 1]])
print("\nOur Masked Array\n", maskArr)
print("\nOur Masked Array type...\n", maskArr.dtype)

# Get the itemsize of the Masked Array
print("\nOur Masked Array itemsize...\n", maskArr.itemsize)

# 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 get the Tuple of bytes to step in each dimension when traversing an array, use the ma.MaskedArray.strides attribute in Numpy
print("\nStrides...\n",maskArr.strides)

Output

Array...
[[35 85]
[67 33]]

Array type...
int64

Array itemsize...
8
Array Dimensions...
2

Our Masked Array
[[35 85]
[67 --]]

Our Masked Array type...
int64

Our Masked Array itemsize...
8

Our Masked Array Dimensions...
2

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

Elements in the Masked Array...
4

Strides...
(16, 8)
raja
Updated on 22-Feb-2022 06:44:50

Advertisements