Any post containing code examples

The One Billion Row Challenge (1BRC) is a fun exploration of how far modern Java can be pushed for aggregating one billion rows from a text file. Grab all your…

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The Fast Fourier Transform (FFT) algorithm to calculate discrete Fourier transforms (DFT) is a recent addition to ojAlgo. The last blog post was about Image Processing (using Singular Value Decomposition,…

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https://lemire.me/blog/2022/11/22/what-is-the-size-of-a-byte-array-in-java Came across this blog post by Daniel Lemire. It's not his most interesting or informative post, but made me remember a little utility I wrote many years ago. MemoryEstimator…

Continue ReadingThe Memory Estimator

The main benefit with ojAlgo's suite of mathematical optimisation solvers is that it's open source pure Java. It allows to solve mathematical optimisation problems directly in the JVM – no…

Continue ReadingOptimisation-as-a-Service

A comparison between some iterative methods to solve linear equation systems. We'll compare 3 different methods: Jacobi, Gauss-Seidel and the Conjugate Gradient method. First the Jacobi and Gauss-Seidel methods are…

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Imagine there's a sequence of operations you need to perform on a dataset, and this dataset is very large. There is absolutely no way the entire dataset could fit in…

Continue ReadingIntroducing BatchNode

With ojAlgo v51.2.0 the IntegerSolver gained support for Gomory Mixed Integer (GMI) cuts. Details of what they are and how they're derived is described in many publications. Just google it.…

Continue ReadingGomory Mixed Integer Cuts