Multiply tensors containing matrices, following matrix multiplication rule Question: Say I have a tensor, where A, B, C, and D are all 2×2 matrices: M = [[A, B], [C, D]] How do I get to the power of n, for example with n=2, with Python or MATLAB M^2 = [[A@A + B@C, A@B + B@D], …
Python 3 matrix calculator Question: I have an issue with this code, It works wrong on option 7 at least is the main problem, It should do the matrix modify and save new value like 2A(A s 2) should be saved on A and maybe because it doesn’t update to new value it gives wrong …
How do I write a python function to maximize sum of N X N upper left sub-matrix from given 2N X 2N matrix? Question: I have this problem to solve: Given a 2N x 2N matrix of integers, you are allowed to reverse any row or column any number of times and in any order. …
Optimize this linear transformation for images with Numpy Question: Good evening, I’m trying to learn NumPy and have written a simple Linear transformation that applies to an image using for loops: import numpy as np M = np.array([ [width, 0], [0, height] ]) T = np.array([ [1, 3], [0, 1] ]) def transform_image(M, T): T_rel_M …
How to reshape matrices using index instead of shape inputs? Question: Given an array of shape (8, 3, 4, 4), reshape them into an arbitrary new shape (8, 4, 4, 3) by inputting the new indices compared to the old positions (0, 2, 3, 1). Asked By: mariogarcc || Source Answers: Numpy’s transpose "reverses or …
Values in numpy matrix based on an array using index and value of each element Question: I would like to use a numpy array to index a numpy matrix using the values of the array indicating the columns, and indices indicating the corresponding row numbers.As an example, I have a numpy matrix, a = np.tile(np.arange(1920), …
OpenCV Mat cpp operation only on condition Question: Having a hard time figuring out how to do this python operation in c++ without looping. The goal is to perform an operation only on a part of the cv::Mat that meets a condition. In this case, scaling values of the image that were originally between -5 …
Sorting matrix columns Question: I have a matrix 4*5 and I need to sort it by several columns. Given these inputs: sort_columns = [3, 1, 2, 4, 5, 2] matrix = [[3, 1, 8, 1, 9], [3, 7, 8, 2, 9], [2, 7, 7, 1, 2], [2, 1, 7, 1, 9]] the matrix should first …
Indexing ndarray with unknown number of dimensions with range dynamically Question: I have data array with unknown shape and array bounds of bounds for slicing data. This code is for 3D data, but is there any way of generalizing this to N-dim? for b in bounds: l0, u0 = b[0] l1, u1 = b[1] l2, …
How to use numpy instead of for loop with different vectors Question: I want to improve my code to make it faster and for now, I have a for loop that I don’t know how to replace it with numpy functions. import numpy as np N = 1000000 d = 2000 p = np.linspace(0,210,211) alpha …
