Dear all:

Dear Friends:

I'm relatively new to Smath and I have a question that I've been trying to solve for a long time and I can't find a way.

This is to use the "diff" function to differentiate an expression with respect to the variable that is an element of a vector, just like the "Jacob" function does. Here is an example:



Hope you can help me and tell me how to derive a expression with respect to the correct varible name.

Best wishes to all,

Mario

I could not tell you why this works.. but assigning another variable the value of q.d[i seems to work.

Jacobiano.sm (8 KiB) downloaded 31 time(s).

Something like this ?
Jean

Maths Jacobian Example.sm (7 KiB) downloaded 31 time(s).

Wrote

I could not tell you why this works.. but assigning another variable the value of q.d[I] seems to work.

Jacobiano.sm (8 KiB) downloaded 31 time(s).

Thank you very much!, it works fine. I am also wandering why, but it works!

Wrote

Something like this ?
Jean

Maths Jacobian Example.sm (7 KiB) downloaded 31 time(s).

Thank you very much, the solution proposed by alyles works fine.

The worksheet you are attaching is something different. But thank you very much in any case.