Maxima -- GPL CAS based on DOE-MACSYMA / Bugs / #2794 question on diff after load(itensor)

#2794 question on diff after load(itensor)

Milestone: None

Status: open

Owner: nobody

Labels: None

Priority: 3

Updated: 2014-10-11

Created: 2014-08-04

Private: No

Hi Maxima gurus:

After loadind itensor

I understand
diff(x([],[2]),x([],[1])); -> kdelta([1],[2])
ev(%,kdelta); -> 0

I understand
diff(cos(x([],[2])),x([],[2])); -> -kdelta([2],[2])*sin(x([],[2]))
ev(%,kdelta); -> -sin(x([],[2]))

But I don't understand
diff(cos(x([],[2])),x([],[1])); -> 'diff(cos(x([],[2])),x([],[1]));

Why isn't de derivate carried out?
How can I make it do the derivative?
Isn't the result: -kdelta([2],[1])*sin(x([],[2]))

I'm using "5.31.2" on Windows

Thanks,

Daniel