Why I got the error "Undefined operator '.*' for input arguments of type 'function_handle"?

RCac = @(~,state) (-k4.*(state.u(1)./K3+state.u(1)).^2+...
    k3.*state.u(1)./(KCICR+state.u).*(IP3./(IP3+K2)).^3.*Cas)...
    -kon.*state.u(1).*(BT-CaB)+koff.*CaB;

s = @(x, y) RCac;

Fe = wOmega(1) * PhiIPS(:, 1) .* s(ip(1, 1), ip(1, 2)) * areaOfElement + ...
         wOmega(2) * PhiIPS(:, 2) .* s(ip(2, 1), ip(2, 2)) * areaOfElement + ...
         wOmega(3) * PhiIPS(:, 3) .* s(ip(3, 1), ip(3, 2)) * areaOfElement;

I keep receiving the error message:

     'function_handle' 型の入力引数の演算子 '.*' が未定義です。

エラー: BarbeeModel (line 159)
    Fe = wOmega(1) * PhiIPS(:, 1) .* s(ip(1, 1), ip(1, 2)) * areaOfElement + ...

in English:

Undefined operator '.*' for input arguments of type 'function_handle'.

Error in
Fe = wOmega(1) * PhiIPS(:, 1) .* s(ip(1, 1), ip(1, 2)) * areaOfElement + ...

Answer 1

[Steven Lord]

You can't multiply a function handle, which is what s returns. If you intend s to evaluate the function handle RCac, just make it an alias of that function handle.

s = RCac;

Or if you wanted to make it explicit in that line of code that s is a function handle:

s = @(x, y) RCac(x, y);

In either of these cases s(something, somethingElse) returns a number rather than a function handle, and you can multiply a number by another number.