Plus42 Equations, Preview Release

[roberto_abraham]

(12-19-2021 11:11 AM)Thomas Okken Wrote:  My plan for name resolution is slightly more elaborate: search the current directory, and ancestors all the way to the root directory, but in addition, also a PATH directory where you can put symlinks to other directories, which will be searched from anywhere. So you don't have to clutter up the root directory with all the things that should be globally available.

That sounds very useful! The feature set of Plus42 sounds absolutely wonderful.

In case it helps to have an edge case for a user-defined unit to think about, a unit that I use all the time but which I think would be handy (but challenging) to incorporate as a user-defined unit is the Rayleigh (R). This is a unit of photon radiance defined as:

1 R = 1/(4 pi) 10^10 photon sec^−1 m^−2 Sr^−1

I bet this turns out to be a tricky edge case, since it involves two somewhat special situations. While 'photon' is part of the definition, it's just a dimensionless pure number that doesn't reduce to an SI base unit and instead should get carried along in calculations but stay symbolic. On the other hand, the solid angle is dimensionless but transforms to other dimensionless solid angle measures that have different exponents (e.g. arcsec^-2).