#162 ezUnits Missing unit conversion in function arguments

[Gunter Königsmann]

For many tasks ezUnits works just like magic:

(%i7)   load("ezunits")$
        sqrt((1`Ohm)*(1`Ohm));
(%o7)   1 ` Ohm

If the square ohms inside the root are expressed differently there seems to be no obvious
way to make ezUnits cope with that, though:

(%i4)   sqrt((1`Ohm)*(1`Ohm+(1`V)/(1`A)));
(%o4)   sqrt((1 ` Ohm)*(1 ` V/A+1 ` Ohm))

(%i5)   %``Ohm;
(%o5)   sqrt((1 ` Ohm)*(1 ` V/A+1 ` Ohm)) `` Ohm

Originally reported as ezUnits and unit conversions in function arguments to the maxima-discuss mailing list.

[Robert Dodier]

Ticket moved from /p/maxima/bugs/3942/

[Robert Dodier]

I've created an initial attempt to implement a function, add_compatible_units, to handle the situation described here. See the folder more_ezunits in: https://github.com/maxima-project-on-github/maxima-packages/tree/master/robert-dodier

As it stands, add_compatible_units could benefit from a stronger way to infer to what common unit terms should be converted, or else (or in addition) a way to hint the common unit. In the absence of that stuff, I think I'm more comfortable with add_compatible_units being in the external project maxima-packages.