Units in TRestDetectorGas

[nkx111]

I think we should make a same system of units for TRestDetectorGas. Now the diffusion units are cm^0.5 and the e-Field units are V/mm. Moreover the plotting methods receive input field in V/cm. This is very confusing. Maybe we can make all the distance field in unit mm, as in REST standard unit system.

[nkx111]

The conversion is supported from TRestSystemOfUnits that 1*(cm^0.5)==0.316*(mm^0.5). I think it is easy to convert diffusion parameters to standard unit.

[jgalan]

Right, it is confusing, but for me it is strange to express field and diffusion in V/mm and mm^0.5. I am pretty much used to V/cm and cm^0.5, for those parameters. So it could be that units are stored internally in mm and V/mm but we operate them in V/cm? Just as it is done at the plotting methods.

Perhaps @cmargalejo or @juanangp got any insights here

[cmargalejo]

In my opinion it should be compulsory for the user to include the units and then REST can internally convert them to the standard unit system if required. I think that would avoid a lot of problems. In case this is not possible, I would keep the same units everywhere even if we are not used to them, so that any new user (and experienced user!) knows exactly what to expect.