Matlab symbolic function conversion without dot for matrix operation

When converting symbolic expression to matlabFunction, expression like

    x=sym('x')
    f=- x^3/6 + x
    g=matlabFunction(f)

    -> @(x)x-x.^3.*(1.0./6.0)

which is not what I want because x is gonna be a matrix and my application requires actual matrix multiplication such as x^3 instead of the dot product form of x.^3

The only way to get it working is to use anonymous function, i.e.

    g=@(x) - x^3/6 + x

    ->@(x)-x^3/6+x

However, the issue with anonymous function is that I cannot use substitution but to type the entire formulation, i.e.

    g=@(x) eval(f)

If I do that, the anonymous function will treat the multiplication as dot product once again :(

In short, I will need to solve either one of the technical difficulties: (1) If I use matlabFunction, how do I remove all the dot after the conversion? or (2) If I use anonymous function, how do I bypass typing the symbolic expression if I have already defined 'f' for the expression?

I am totally lost here and I hope someone familiar with matlab can give me 2 cents.

Thank you!

Answer 1

[Yeshwanth Devara]

I am from MathWorks and I have notified the respective team about this limitation. One workaround for now is to use regex on the existing function and create matrix power as follows:

x=sym('x')
f=- x^3/6 + x
g=matlabFunction(f)
newg=str2func( regexprep(func2str(g),'\.(\*|\^)','$1') )

For inline solution:

x=sym('x')
f=- x^3/6 + x
g= str2func( regexprep(func2str(matlabFunction(f)),'\.(\*|\^)','$1') )