Turn a numeric function into a symbolic one

Hi all,

do you know ho to turn a function with numeric input and output into a symbolic function?

Thanks!

Answer 1

[Doug Hull]

You will have to enter the function manually if you know it.

[Antonio]

Ok, so I guess it is not possible since my numerical function depends on other numerical functions to be defined.

[Antonio]

I should define all the functions as symbolic ones

Answer 2

[Walter Roberson]

In the case where the numeric function only involves mathematical calculations with respect to the parameter you wish to be symbolic, then pass a symbol to the numeric function.

If the numeric function has any part that is conditional on the input value (e.g., an "if" statement) then there is no mechanical way of handling the situation.

[Antonio]

how do you pass a symbolic variable to a numerical function?

[Antonio]

and eventually get a symbolic result?

[Walter Roberson]

Just call the function passing in a symbolic variable. Operator overloading takes care of the details.

For example,

f = @(x) sin(cos(x)^2-tan(x))

then

syms p

f(p)