Conda + Fortran| degenerateconic.com
Root Finding| degenerateconic.com
Old School| degenerateconic.com
Great Circle| degenerateconic.com
A Modern Fortran Scientific Programming Ecosystem| degenerateconic.com
Direct and Inverse| degenerateconic.com
Modified Equinoctial Elements| degenerateconic.com
Fortran 2023 (ISO/IEC 1539-1:2023) has been officially published. This replaces the previous standard (Fortran 2018). In a previous post I listed the updates that are in this release (then called "Fortran 202x"). It will be a while before we have fully-compliant Fortran 2023 compilers. In the latest update …| Degenerate Conic
Some Earth-Moon NRHOs. From Williams et al, 2017. I have mentioned the Circular Restricted Three-Body Problem (CR3BP) here a couple of times. Another type of periodic CR3BP orbit is the "near rectilinear" halo orbit (NRHO). These orbits are just the continuation of the family of "normal" halo orbits until they …| Degenerate Conic
NightCafe AI generated image for "old computers" The classic Fortran routines r1mach (for single precision real numbers), d1mach (for double precision real numbers), and i1mach (for integers) were originally written in the mid-1970s for the purpose of returning basic machine or operating system dependent constants in order to provide portability …| Degenerate Conic
In today's episode of "What where the Fortran dudes in the 1980s thinking?": consider the following code, which can be found in various forms in the two SLATEC quadrature routines dgaus8 and dqnc79: K=I1MACH(14)ANIB=D1MACH(5)*K/0.30102000D0NBITS=ANIB Note that the "mach" routines (more …| Degenerate Conic
The glacially slow pace of Fortran language development continues! From the smoke-filled room of the Fortran Standards Committee, the next Fortran standard is coming along. It has not yet been given an official name but is currently referred to as "Fortran 202x" (so hopefully we will see it before the …| Degenerate Conic
There are a lot of classic Fortran libraries from the 1970s to the early 1990s whose names end in "pack" (or, more specifically, "PACK"). I presume this stands for "package", and it seems to have been a common nomenclature for software libraries back in the day. Here is a list …| Degenerate Conic
Modified Equinoctial Elements| degenerateconic.com
Gooding Universal Elements| degenerateconic.com
One of my major pet peeves about Fortran is that it contains virtually no high-level access to the file system. The file system is one of those things that the Fortran standard pretends doesn't exist. It's one of those idiosyncratic things about the Fortran standard, like how it uses the …| Degenerate Conic
Atmosphere Models| degenerateconic.com
Great Circle| degenerateconic.com
With the right plugins, Microsoft Visual Studio Code can be turned into a very good modern Fortran IDE. Here are some of my favorites: FORTRAN IntelliSense (hansec.fortran-ls). To use this, you must pip installfortran-language-server. vscode-modern-fortran-formatter (yukiuuh.vscode-modern-fortran-formatter). To use this, you must pip installfprettify. Modern Fortran (krvajalm …| Degenerate Conic
A Modern Fortran Scientific Programming Ecosystem| degenerateconic.com