Non-Linear Least Squares Minimization, with flexible Parameter settings, based on scipy.optimize, and with many additional classes and methods for curve fitting.

End-to-end Lane Detection for Self-Driving Cars (ICCV 2019 Workshop)

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A general and flexible factor graph non-linear least square optimization framework

oj! Algorithms

Six snippets of code that made deep learning what it is today.

Opt DSL

Symbolic Fitting; fitting as it should be.

A generalized inverse kinematics solver that supports closed chains for parallel kinematics systems, dynamic reconfiguration, and arbitrary joint configuration based on damped least squares error minimization techniques

Taking a Deeper Look at the Inverse Compositional Algorithm (CVPR 2019, Oral)

Fitting an Ellipse using a Least Squares method, in Python

Least squares conformal mapping implemented in C++

A single header-only C++ library for least squares fitting.

Modernized Minpack: for solving nonlinear equations and nonlinear least squares problems

A sharing of the learning process of mathematical modeling 数学建模常用工具模型算法分享：数学建模竞赛优秀论文，数学建模常用算法模型，LaTeX论文模板，SPSS工具分享。

FIR & LMS filter implementation in C++ with Python & JAVA wrappers

Least squares adjustment software

Vanishing Point detection for images and videos using Least Squares in C++

Find ellipsoid fit for arbitrary data with python/numpy, plot it or write to file.