i want to find the transpose of the matrix m but showing error. please can anyone help with the error

function [m]=calc_m()
m_rot()=@(w) [0;cos(w);sin(w)];
Q=[0.4082,0.4082,-0.8165;0.7017,-0.7071,0;0.5774,0.5774,0.5774];
m()=@(w) Q*m_rot();
z=m.'

Answer 1

[Geoff Hayes]

sadgun - can't you just do

z=m';

without the period? Though I'm not sure why you are setting this result to z since your function output parameter is m. Perhaps the above line of code should just be

m=m';

or the function signature should change to indicate that z is the output parameter.

Though perhaps this isn't the error? When I try to run your code, the first error is

 m_rot()=@(w) [0;cos(w);sin(w)];
      |
Error: An indexing expression on the left side of an assignment must have at least one
subscript.

Remove the brackets so that the assignment is just

m_rot = @(w) [0;cos(w);sin(w)];

The assignment for m will have the same problem so that should probably be

m = Q * m_rot(w);

where w is some value. Remember that m_rot is a function handle and so requires an input. Is this even correct though? Do you expect m to be a 3x1 matrix or should it be a rotated 3x3 matrix? Please clarify.

[sadgun pulagam]

Thank you for answering my question.

I want m also to be a function handle of w and then transpose m. because i want to use transpose of m in an integration function which i have defined it in later part of my code. this integration contains limits of w.

can't i transpose a m which is a fuction handle.

yes i want m to be 3x1 matrix.

[madhan ravi]

m=@(w) Q*m_rot(w);
z=m(w).'

[sadgun pulagam]

'undefined function 'cos' for input argument of type 'function handle'

This error is poping if i write as above and passing it to another function calling it.

[madhan ravi]

Upload the code that you are trying including the function call/s with datas.

[sadgun pulagam]

i am attching a file below.

[sadgun pulagam]

i am basically calculating K , with inputs c11,c12,c44. B is a variable which is integral of a function over 0 to 2pi. all other are given. if anything required please let me know.

[Walter Roberson]

Please post some sample inputs so we can run your code.

[sadgun pulagam]

c11=169.9, c12=122.6, c44=76.2

these are the only inputs required i hope. other all are given inside the code itself.

[Walter Roberson]

Your calc_m_n returns function handles for m and n.

Then on line 33 you have

mat_uv(i,j)=mat_uv(i,j)+z(k)*mat_C(k,i,j,l,c11,c12,c44)*m(@(w)(l));

This calls the function handle m, passing in a function handle @(w) (l) . That is a function handle that, if executed, would accept any input and return the current value of l (lower-case L) as of the time the anonymous function was created.

The function handle that was returned for m involves Qinv and taking its parameter (w) and applying a matrix rotation to it by way of m_rot . That involves taking the cos() of the argument. But the argument is the function handle @(w)(l) and you cannot take the cos of a function handle.

It is not at all obvious why you use @(w)(l) as the argument to m on line 33, since on the next line, line 34, where you invoke the very similar n, you just pass in l instead of an anonymous function that encapsulates l like you do for m