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An inline function is created from a string containing the function
body using the inline
function. The following code defines the
function f(x) = x^2 + 2.
f = inline ("x^2 + 2");
After this it is possible to evaluate f at any x by
writing f(x)
.
Caution: MATLAB has begun the process of deprecating inline functions. At some point in the future support will be dropped and eventually Octave will follow MATLAB and also remove inline functions. Use anonymous functions in all new code.
Create an inline function from the character string str.
If called with a single argument, the arguments of the generated
function are extracted from the function itself. The generated
function arguments will then be in alphabetical order. It should
be noted that i, and j are ignored as arguments due to the
ambiguity between their use as a variable or their use as an inbuilt
constant. All arguments followed by a parenthesis are considered
to be functions. If no arguments are found, a function taking a single
argument named x
will be created.
If the second and subsequent arguments are character strings, they are the names of the arguments of the function.
If the second argument is an integer n, the arguments are
"x"
, "P1"
, …, "PN"
.
Programming Note: The use of inline
is discouraged and it may be
removed from a future version of Octave. The preferred way to create
functions from strings is through the use of anonymous functions
(see Anonymous Functions) or str2func
.
Return a cell array of character strings containing the names of the arguments of the inline function fun.
Return a character string representing the inline function fun.
Note that char (fun)
is equivalent to
formula (fun)
.
Identify the symbolic variable names in the string str.
Common constant names such as i
, j
, pi
, Inf
and
Octave functions such as sin
or plot
are ignored.
Any names identified are returned in a cell array of strings. The array is empty if no variables were found.
Example:
symvar ("x^2 + y^2 == 4") ⇒ { [1,1] = x [2,1] = y }