For a number of years I have been familiar with the observation that the quality of programmers is a decreasing function of the density of go to statements in the programs they produce. — Edsger W. Dijkstra One of the classics…

Degenerate Conic
Algorithms, modern Fortran programming, and orbital mechanics

For a number of years I have been familiar with the observation that the quality of programmers is a decreasing function of the density of go to statements in the programs they produce. — Edsger W. Dijkstra One of the classics…

Here’s another example using the C interoperability features of modern Fortran. First introduced in Fortran 2003, this allows for easily calling C routines from Fortran (and vice versa) in a standard and portable way. Further interoperability features will also be added…

It looks like JPL just opensourced their MATH77 Fortran library. MATH77 is a library of Fortran 77 subroutines implementing various numerical algorithms. It was developed over decades at JPL, and contains some very high-quality and time-tested code. The code is released under a BSD-type license. There…

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…

There is a lot of confusion and misinformation about the Fortran programming language on the internet, and a general ignorance about it among programmers. Most younger programmers who use languages invented five minutes ago probably have never seen it, and may only be dimly…

The Standards of Fundamental Astronomy (SOFA) library is a very nice collection of routines that implement various IAU algorithms for fundamental astronomy computations. Versions are available in Fortran and C. Unfortunately, the Fortran version is written to be of maximum use to astronomers who…

The ISO_C_BINDING intrinsic module and the BIND attribute introduced in Fortran 2003 are very handy for producing standard and portable Fortran code that interacts with C code. The example given here shows how to use the popen, fgets, and pclose routines…

## Comments

I just came across this article from 2005 written by Jef Raskin (probably most famous for having initiated the Macintosh project at Apple) on source code documentation [1]. I agree with much of what he recommends. I have never believed that code can…