## Numerical Differentiation

I present the initial release of a new modern Fortran library for computing Jacobian matrices using numerical differentiation. It is called NumDiff and is available on GitHub. The Jacobian is the matrix of partial derivatives of a set of $$m$$ functions

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## SLSQP

SLSQP [1-2] is a sequential quadratic programming (SQP) optimization algorithm written by Dieter Kraft in the 1980s. It can be used to solve nonlinear programming problems that minimize a scalar function: subject to general equality and inequality constraints: and to lower

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## Refactoring

SLSQP [1-2] is a sequential least squares constrained optimization algorithm written by Dieter Kraft in the 1980s. Today, it forms part of the Python pyOpt package for solving nonlinear constrained optimization problems. It was written in FORTRAN 77, and is filled

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## Earth-Mars Free Return

Let’s try using the Fortran Astrodynamics Toolkit and Pikaia to solve a real-world orbital mechanics problem. In this case, computing the optimal Earth-Mars free return trajectory in the year 2018. This is a trajectory that departs Earth, and then with

Posted in Orbital Mechanics, Programming Tagged with: , , , , ,

## Pikaia

I’ve started a new project on Github for a new modern object-oriented version of the Pikaia genetic algorithm code. This is a refactoring and upgrade of the Pikaia code from the High Altitude Observatory. The original code is public domain and was

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