numpy.ravel() in Python
The numpy.ravel() functions returns contiguous flattened array(1D array with all the input-array elements and with the same type as it). A copy is made only if needed.
Syntax :
numpy.ravel(array, order = 'C')
Parameters :
array : [array_like]Input array. order : [C-contiguous, F-contiguous, A-contiguous; optional] C-contiguous order in memory(last index varies the fastest) C order means that operating row-rise on the array will be slightly quicker FORTRAN-contiguous order in memory (first index varies the fastest). F order means that column-wise operations will be faster. ‘A’ means to read / write the elements in Fortran-like index order if, array is Fortran contiguous in memory, C-like order otherwise
Return :
Flattened array having same type as the Input array and and order as per choice.
Code 1 : Shows that array.ravel is equivalent to reshape(-1, order=order)
- Python
# Python Program illustrating# numpy.ravel() methodimport numpy as geekarray = geek.arrange(15).reshape(3, 5)print("Original array : \n", array)# Output comes like [ 0 1 2 ..., 12 13 14]# as it is a long output, so it is the way of# showing output in Pythonprint("\nravel() : ", array.ravel())# This shows array.ravel is equivalent to reshape(-1, order=order).print("\nnumpy.ravel() == numpy.reshape(-1)")print("Reshaping array : ", array.reshape(-1)) |
Output :
Original array : [[ 0 1 2 3 4] [ 5 6 7 8 9] [10 11 12 13 14]] ravel() : [ 0 1 2 ..., 12 13 14] numpy.ravel() == numpy.reshape(-1) Reshaping array : [ 0 1 2 ..., 12 13 14]
Code 2 :Showing ordering manipulation
- Python
# Python Program illustrating# numpy.ravel() methodimport numpy as geekarray = geek.arrange(15).reshape(3, 5)print("Original array : \n", array)# Output comes like [ 0 1 2 ..., 12 13 14]# as it is a long output, so it is the way of# showing output in Python# About :print("\nAbout numpy.ravel() : ", array.ravel)print("\nnumpy.ravel() : ", array.ravel())# Maintaining both 'A' and 'F' orderprint("\nMaintains A Order : ", array.ravel(order = 'A'))# K-order preserving the ordering# 'K' means that is neither 'A' nor 'F'array2 = geek.arrange(12).reshape(2,3,2).swapaxes(1,2)print("\narray2 \n", array2)print("\nMaintains A Order : ", array2.ravel(order = 'K')) |
Output :
Original array : [[ 0 1 2 3 4] [ 5 6 7 8 9] [10 11 12 13 14]] About numpy.ravel() : numpy.ravel() : [ 0 1 2 ..., 12 13 14] Maintains A Order : [ 0 1 2 ..., 12 13 14] array2 [[[ 0 2 4] [ 1 3 5]] [[ 6 8 10] [ 7 9 11]]] Maintains A Order : [ 0 1 2 ..., 9 10 11]
References :
https://docs.scipy.org/doc/numpy-dev/reference/generated/numpy.ravel.html#numpy.ravel
Note :
These codes won’t run on online-ID. Please run them on your systems to explore the working
Last Updated on March 1, 2022 by admin