Calculating of multivariate symbolic expression with numeric data

HI

I need to calculate integral over a Multivariate function,

the function is a product of some 3x3 "analytic" matrices which can be easily calculated using symbolic math,

Here is a simple function which I need to calculate :

syms t p
R=[ cos(p) sin(p) 0
 -sin(p) cos(p) 0
  0 0 1];

 L1=[ cos(t)  0      sin(t)
      0      1       0
    -sin(t)  0      cos(t) ];

 e0=[1;1;1]

 F=inv(R)*inv(L1)*R*e0

the result :

 F =

 sin(p)^2 - cos(p)*sin(t) - cos(p)*sin(p) + cos(p)^2*cos(t) + cos(p)*cos(t)*sin(p)

 cos(p)^2 - sin(p)*sin(t) - cos(p)*sin(p) + cos(t)*sin(p)^2 + cos(p)*cos(t)*sin(p)

 cos(t) + cos(p)*sin(t) + sin(p)*sin(t)

After having the function what is the best way to calculate it over a set of numerical data for p,t (phi,theta) ??

10x

Answer 1

[Walter Roberson]

Fnum = matlabFunction(F, p, t);

This would create a MATLAB function that had p as its first argument and t as its second argument and which returned an array of numeric values.

[Elad]

Hi,

thanks for your resopne, i tried it but it doesn't work

i also tried a simple function and still cant make it work.

how do you use it after converting it to matlab function?

simple function:

syms t p

R=sqrt(t*t+p*p);

Fnum = matlabFunction(R, p, t);

x=-5:1:5 ;

[X Y]=meshgrid(x,x);

[X1 Y1]=Fnum(X,Y)

[X2 Y2]=Fnum(1,1)

10x again

[Walter Roberson]

Those forms should work, it appears to me. What shows up if you display Fnum ?

[Alexander]

Try:

Fnum = matlabFunction(R, 'vars', [p, t]);

[Elad]

Thank u both, The last line gives the solution.