I have been playing around with equations for electric systems using Sympy, and have already manage quite a lot so that equation look nice and decent : all values hold units which are following them even trough combinations of equations. That's quite important I think, because the aim is that the document I am writing to calculate my values IS the final document I will present (I'm using Jupyter notebooks and will PDF the whole thing).
Now come my problem : somehow, sympy decided that % are not a unit by itself (true enough, it has no dimension) and that it makes no sense to show it - at all. It seems to even parse my self declared units to remove any percent character that could appears ...
As long as I agree that % have no dimension, the character still exist for a reason - if it was that useless, it would have not existed to begin with. Humans like to read percents with a nice % at the end, because it already indicate that the result has been multiplied by a factor of 100. It also make the result more readable.
In code :
# imports
import sympy as sp
from sympy import init_printing
init_printing(use_latex=True)
init_printing(use_latex='mathjax')
import sympy.physics.units as u
from IPython.display import display
#define unit
percent = u.Unit('ab%c', 'ab%c')*100 # a,b and c are only there for debug. Only % is needed
#define dummy equation
Error_= sp.symbols('Error')
total_error = 1 # error is not yet in %. 1 means 100%
Eq = sp.Eq(Error_, total_error*percent)
display(Eq)
result : Error=100ab
Why is everything after the % plainly removed ? I've even been careful not to import all units in the global namespace so if % were to be detected, wouldn't it need u.% ?
PS: I have a long history of 3 days (total) working with Python. I'm usually more of a C guy. Hope I've not missed a stupid error.
