Maxima Function
showcomps (tensor)
Shows component assignments of a tensor, as made using the components
command. This function can be particularly useful when a matrix is assigned
to an indicial tensor using components
, as demonstrated by the
following example:
(%i1) load(ctensor); (%o1) /share/tensor/ctensor.mac (%i2) load(itensor); (%o2) /share/tensor/itensor.lisp (%i3) lg:matrix([sqrt(r/(r-2*m)),0,0,0],[0,r,0,0], [0,0,sin(theta)*r,0],[0,0,0,sqrt((r-2*m)/r)]); [ r ] [ sqrt(-------) 0 0 0 ] [ r - 2 m ] [ ] [ 0 r 0 0 ] (%o3) [ ] [ 0 0 r sin(theta) 0 ] [ ] [ r - 2 m ] [ 0 0 0 sqrt(-------) ] [ r ] (%i4) components(g([i,j],[]),lg); (%o4) done (%i5) showcomps(g([i,j],[])); [ r ] [ sqrt(-------) 0 0 0 ] [ r - 2 m ] [ ] [ 0 r 0 0 ] (%t5) g = [ ] i j [ 0 0 r sin(theta) 0 ] [ ] [ r - 2 m ] [ 0 0 0 sqrt(-------) ] [ r ] (%o5) false
The showcomps
command can also display components of a tensor of
rank higher than 2.