Questions tagged [linear-algebra]
For code aims to resolve problems of linear algebra like vectors, vectorial space, linear transformations and systems of equations.
19 questions
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C - SIMD Code to invert a transformation matrix
I am writing a maths library for a raytracer project, and so I'm trying to make my heavy operations (like matrix inverse) more optimised. After doing some research, I discovered this trick to invert a ...
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Solving upper triangular matrix-vector equation in Rust
Most linear algebra libraries written for Rust, e.g. nalgebra or ndarray have type or trait requirements that mean their ...
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Determinant of matrix Python
This is an addition of my previous question Python matrix class. I've added a determinant function using Laplace expansion to my Matrix class. What I am looking for specifically is how 3x3 matrices ...
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Python matrix class
To prepare for my studies in linear algebra, I've decided to write a simple matrix class. This is the initial program, with functions to find the determinant and decomposition(s) to follow. I wanted ...
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Multithreaded sparse linear solver in Python
I would like to know if there are any multithreaded sparse linear solvers for LU decomposed sparse matrices.
I want to increase the solving speed of a system like:
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Find highest number of swaps within a set of possible duty swaps with networkx and PuLP
With huge help from Stack Overflow, I have created code which takes possible swap matches with given weights as an input and outputs a set of matches which gives the highest weight with the highest ...
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Scene Hierarchy with Translation, Rotation and Scale
This code represents an Entity Component that holds and manipulates an entity's local and world transforms, dealing with hierarchy and translation/rotation/scale transformations. The code is written ...
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Python manual SVD only working for some matrices - how to stabilize it? [closed]
I use the following code for a manual single value decomposition using numpy. Depending on the array I choose it sometimes works out well and I can verify the svd and sometimes it does not work out ...
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Implementing Preconditioned conjugate gradient
I have implemented the Preconditioned Conjugate Gradient (PCG) method for solving a system of linear equations in Python and I would appreciate it if someone could verify its correctness since I am ...
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Python integer optimization with PuLP involving polynomials that I think can be faster
I have a problem where we are given multivariate polynomials in variables like y_i and z_j and the goal is to express them as sums of products of terms of the form y_i-z_j with nonnegative integer ...
- 225
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Generic matrix library in Java
I have this repository. The most important source files follow.
com.github.coderodde.math.linear.matrix.AbstractMatrix.java:
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Implementing PLU Decomposition in Rust
I am using abstalg, because I wanted to learn more about how to do this with generic fields, (So you can implement LU decomposition not just for floats). I used ...
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An implementation of Givens method for diagonalising symmetric matrices
So I tried to create a code which aims to diagonalise symmetric matrices via Givens algorithm. The program only works for symmetric matrices, for we know a symmetric matrix is always diagonalisable, ...
- 121
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1
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557
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Matrix-vector multiplication with block-column distribution and MPI_Reduce_scatter
I'm studying MPI and I'm trying to solve the exercise (number 3.5) taken from Pacheco's book Introduction to parallel programming. Essentially the exercise is:
Write an MPI program that computes the ...
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Yet another mathematical vector class
This is an implementation of a mathematical vector.
I am currently working on a linear algebra project and before proceeding further with other classes (matrix, polar_vector etc.) I would like to have ...
2
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2
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Coordinate Descent Non-negative Least Squares optimization
In my fast implementation of Non-negative Matrix Factorization (Rcpp Machine Learning Library, RcppML), about 40% of the runtime is spent solving Non-negative Least Squares (NNLS) systems (the rest of ...
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Why is this tensor contraction so slow and how can I make it faster?
I am trying to calculate a specific complicated tensor contraction (of complex valued tensors) which appears as part of some other calculation and is called multiple times in a row, about 100 times or ...
- 203
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Solving a linear system with Gaussian Elimination
I decided to implement a solver for linear systems of equations based on the gaussian elimination and reduction to upper triangular form. The gaussian elimination is quite simple to implement but the ...
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