Author: Jacob

Time Conversions with SPICE

JPL’s SPICE Toolkit (SPICELIB) is the premier software library for computations related to solar system geometry. It is freely distributed, and is also one of the best-documented libraries I have ever come across. SPICELIB also includes a comprehensive set of

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Another One Bites the Dust

JPL recently released an update to their awesome SPICE Toolkit (it is now at version N66). The major new feature in this release is the Digital Shape Kernel (DSK) capability to define the shapes of bodies (such as asteroids) via tessellated plate

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The New Features of Fortran 2015

The glacially slow pace of Fortran language development continues! The next standard, Fortran 2015, mainly consists of updates for Fortran/C interoperability and new coarray features such as teams. In addition, there are a bunch of minor changes and discrepancy fixes. A

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Fortran in the Cloud

You can now try OpenCoarrays and Gfortran in the cloud, courtesy of Zaak Beekman and the Sourcery Institute. Just navigate to and then click “Launch”. This awesome project is enabled by various other awesome tools like Binder, Jupyter, and GitHub. Truly,

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Xojo and Memory Lane

I happened across this article on a programming language and IDE called Xojo. I never used it under this name, but I have fond memories of using it when it was called RealBASIC. I learned it shortly after it came out in the

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It appears that Flang, a new open source Fortran front-end for LLVM, has appeared on GitHub recently with little fanfare. This is apparently the result of NVIDIA’s previously-announced plan to open source the PGI Fortran compiler. Unfortunately, they decided to give it

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Fortran Configuration File Formats

String and file manipulation in Fortran isn’t as bad as you’ve heard (OK, it’s bad, but it’s getting better). Sure, modern Fortran only provides the bare minimum of features for this sort of thing out of the box, but various libraries are starting

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GFortran 7.1

GCC (which includes GFortran) version 7.1 has just been released. Various features from Fortran 2003-2015 have been added, including: User-defined derived-type input/output (UDTIO). Partial support for derived type coarrays with allocatable and pointer components. Non-constant stop codes and error stop

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JSON-Fortran 5.3.0

JSON-Fortran 5.3.0 is out. This release includes a few minor bug fixes and a couple of new features. For one thing, it is now possible to easily build or modify a JSON structure without using pointer variables. Here’s an example: As

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Binary Search

Binary search is a search algorithm that finds the position of a target value within a sorted array. The following binary search routine is taken from NASTRAN, a venerable finite element analysis program from NASA: As you can see, it is a scene of FORTRAN

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