# Question:[HELP] Symbolic differentiation of matrix using Maple

## Question:[HELP] Symbolic differentiation of matrix using Maple

Maple

Hey,

I have one function that is consisted of several matrices.. The function is,

R := log(determinant(MCOV))+trace(multiply(SCOV, inverse(MCOV)))-log(det(SCOV))-2+Transpose(SM-TAU-multiply(L,K))&*inverse(MCOV)&*(SM-TAU-multiply (L, K));

where MCOV, SCOV, SM,TAU, L, K are all matrics. In a MCOV and L, there are symbols also..

I have tried to get second derivative of R function with respect to each symbol.

1017.html

Q1. (Equation 12 in uploaded file) After defining all MCOV, SCOV, SM,TAU, L, and K, I typed R function. The maple showed just (   ) with out anything inside () in the place of " trace(multiply(SCOV, inverse(MCOV))) ". Could anyone explain to me?

Q2. (Equation 13 in uploaded file) When I tried to get one second derivative of R, for example, using

SDL1:=map(Diff,R(L1,L2,F,K), (L1,2));

MAPLE showed that

Diff(ln(determinant(MCOV)) (L1,L2,F,K) L1,2)+Diff(L1,2) +Diff.............

Why didn't MAPLE show the actual results of "Diff(ln(determinant(MCOV)) (L1,L2,F,K) L1,2)"? What should I do to see the result?

Q3. (Equation 25 in uploaded file) Please help me how to get inverse of one matrix in Equation 25!!!! I am almost desperate!!

Thank you guys... Best best  luck in the future to anyone who leave any comment!!!!

Yoonjeong

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