# MATLAB Matlab; Jacobian array calculation question

#### norian

Hi,
i wanna ask a question, if you help me i'll apraciate.

I have a jacobian matris with 4 initial parameters. J [1,1] like:

J =
-1/25-7610043006264749541981/760193818229211136000000*20265^(3/4)*1663^(1/4)*(1/T)^(7/4)/Yf^(9/10)*233^(13/20)*1000^(7/20)*Yox^(33/20)-Ypr

in here. I know T, Yf, Yox and Ypr.
At that problem i m having trouble with putting these parameter inside the jacobian matris because it is a darivative of some function. And printing J gives me that answer. do you know how to do that(calculate J with respect to 4 know parameters)? By the way i m working on matlab. and there are lots of J(as i made J1, J2 etc.) inside a for loop so i cant calculate it by hand :)

Thanks,

as an example;

syms x y z
f = [x*y*z; y; x + z];
v = [x, y, z];
R = jacobian(f, v)

The result is

R =
[ y*z, x*z, x*y]
[ 0, 1, 0]
[ 1, 0, 1]

as vector R in here i found J array above, but i could not give a value for x,y or z to compute R.

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