y(t)= a*t*exp(-a*t); z=summatio​n(A(i)*y(t​-T(i)).sum​mation from i=1 to J. i need to partially differentiate z wrt A() and T()

for the above equation i need to partially differentiate z wrt A() and T() . how do i include the summation in matlab code.

Thank you in advance

[Ced]

summation from i to J? Summation over what? You don't even have indices...

Regardless, there is a sum function. And there is documentation where you can find examples on all the functions you need: diff, sum, syms, etc.

[KOMALA PAWAR]

y(t)= a*t*exp(-a*t); z=summation(A(i)*y(t-T(i)).summation from i=1 to J. i need to partially differentiate z wrt A() and T().

[KOMALA PAWAR]

take J as some value like 4 or 5.

Answer 1

[Ced]

And you want to do this symbolically? Looks to me that this would be a possibility:

1. create a variable for each summation index. You can do this e.g. using the syntax

a_vec = sym('a',1:J);

See Symbolic Variables Documentation

2. define the term z = sum(....)

3. differentiate w.r.t each variable, either in a loop, or in vector form using the jacobian function. See here:

Jacobian documentation