Revision history [back]

This version works better:

%display latex
M = Manifold(4, 'M', latex_name=r'\mathcal{M}', structure='Lorentzian')
X.<t,x,y,z> = M.chart()
F = M.scalar_field(1/(-t^2 + x^2 + y^2 + z^2))
display(F.display())
dF=diff(F)
dF.apply_map(factor)
dF.display()