from galgebra.ga import Ga
from sympy import symbols
from galgebra.printer import Format
Format()
coords = (et,ex,ey,ez) = symbols('t,x,y,z',real=True)
base=Ga('e*t|x|y|z',g=[1,-1,-1,-1],coords=symbols('t,x,y,z',real=True),wedge=False)
potential=base.mv('phi','vector',f=True)
potential
field=base.grad*potential
field
grad_field = base.grad*field
grad_field
part=field.proj([base.mv()[0]^base.mv()[1]])
part
dpart = base.grad*part
dpart