`formula`

Mathematical expression that defines a symbolic function.

Category: Symbolic Computations in MATLAB > Symbolic Variables, Expressions, Functions, and Preferences

Syntax

expr = formula(f)

Returns the body of the symfun f as a plain symbolic expression.

Description

A symfun such as f(x) = x^2 + 1 is more than an expression: it also knows its argument list. formula strips that wrapper and gives the expression, which can then be differentiated, simplified or substituted like any other sym.

When f has been declared but not yet defined, the formula is just the unevaluated call f(x).

Input arguments

f: Symbolic function. A plain sym expression is returned unchanged.

Output arguments

expr: Symbolic expression in the input variables of f.

Example

Extracting the expression

syms f(x)
formula(f)
f(x) = x^2 + 1;
e = formula(f)
class(e)

Output

ans = f(x)
e = x^2 + 1
ans = 'sym'

formula