Questions tagged [eigen]
Eigen is a C++ template library for linear algebra: matrices, vectors, and related algorithms.
20 questions
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Accelerating computation of a "2D Variance" using C++ and Eigen in a MEX function
I have the following function in Matlab:
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8
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3
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2k
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Why/How is Matlab's circshift function so efficient?
I have the following function in Matlab:
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-4
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1
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181
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matrix multiplication in C++ [closed]
I have the following function that takes too long to execute.
I need to made this at least 2x times faster.
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4
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1
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711
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Implementation of Iterative Closest Point in C++
Here, is my implementation of Iterative Closest Point algorithm in C++. The code is written using the Eigen library. I have tried to implement an efficient coding methodology best to my knowledge ...
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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1
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Fractional indexing and interpolation to reconstruct an image
I have a c++ project written as a Matlab Mex program that is constructing an image composed of IxJ pixels. Each pixel value is calculated by finding the contributions to that pixel from all the ...
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1
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Transforming from spherical coordinates to Cartesian coordinates using Eigen
I need to transform the coordinates from spherical to Cartesian space using the Eigen C++ Library. The following code serves the purpose:
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6
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1
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262
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Multivariate normal density using Woodbury matrix inversion lemma
I'm trying to speed up by multivariate normal density function by taking advantage of the fact that the covariance matrix is of the form A + U C U'. The inverse of such a matrix can be calculated ...
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2
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182
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Writting “A Simple Least-Squares Approach” by Longstaff and Schwartz into a C++ class
Background:
I have posted a similar question here. I followed the suggestions of @ Ben Steffan and made the appropriate changes despite number 6 that I did not understand and number 7.
Question:
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3
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Writting "A Simple Least-Squares Approach" by Longstaff and Schwartz; pricing American option contracts
Background:
I have made a post about this on another account here. I am writing the least squares algorithm into a class in C++ and I want to make sure that what I am doing is the most efficient and ...
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2
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0
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428
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Forward Monte Carlo Algorithm in C++
Background Information:
Here is an outline of the algorithm known as Forward Monte Carlo for pricing American options which is from the paper, "A Forward Monte Carlo Method for American Options ...
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Optimizing a function in Eigen
I'm a beginner in C++ and I would appreciate advices to optimize the following function I wrote with Eigen (in fact, to be used with RcppEigen).
So far, I observe a 3.5x speed-up compared to the ...
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Logistic regression with eigen
I am a new to Eigen, and I implemented a logistic regression model with it. It works but I don't know whether it is implemented in an efficient way.
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4
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1
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387
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Simple neural-network simulation in C++ (Round 3)
As I mentioned at the end of my Round 2 answer, I've needed to expand my code in order to produce faithfully the data needed for Figure 1 of this paper.
Unfortunately, the updates have made my script ...
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4
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1
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258
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Simple neural-network simulation in C++ (Round 2)
Intro
Yesterday I posted this question. Since then, I've updated my code to incorporate these suggestions. I've also removed the dependence on C++11. Finally, I've made the following changes that ...
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Simple neural-network simulation in C++
The C++ code below simulates the timecourse of the membrane potential (V) of a population of 128 leaky integrate-and-fire ...
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5
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2
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225
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Computing the RPY tensor with C++/Eigen (linear algebra)
I'm mostly used to writing scientific code in MATLAB / Python / Julia and my experience with C++ is very limited. I've implemented a fairly simple computation of the Rotne-Prager-Yamakawa tensor in ...
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7
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1
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Normalize Sparse Matrix along rows in C++ Eigen
I wrote a function to normalize sparse matrix along rows using C++ Eigen; however, I feel that it can be improved, and that I am not using some built in functions of Eigen.
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Are there any memory issues with this Eigen QR wrapper?
I am writing a wrapper to Eigen QR for my personal use and I am wondering if there are any memory leaks or undocumented behavior in my implementation, especially in the function ...
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3
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2
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6k
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Implementation of Mahalanobis distances using Eigen
I'm trying to learn C++ with Eigen. Here's my attempt at computing
Mahalanobis distances of a set of points x with respect to a sub-matrix ...
- 133