I want to make a programming function in which I want to take input any mathematical function like f(x)=sin(x)+x^2. then I take a input x and my function return a value of f(x).but i don't know how can i do?

I want to make a programming function in which I want to take input any mathematical function like f(x)=sin(x)+x^2. then I take a input x and my function return a value of f(x).but i don't know how can i do?

Answer 1

[Aquatris]

Here is a simple Matlab script;

f_math = @(x) sin(x)+x.^2;% mathematical function, notice the element wise operation
fun = @(f,x) f(x);        % function that takes mathematical function and x 
x = 1:1:100;              % input x
y = fun(f_math,x);        % output f(x)

Answer 2

[James Tursa]

E.g.,

s = input('Input a function of x: ','s');
f = str2func(['@(x)' vectorize(s)]);

Now you have a vectorized function handle version of the function character string that was input from the user. A sample run:

>> s = input('Input a function of x: ','s')
Input a function of x: sin(x) + x^2
s =
sin(x) + x^2
>> f = str2func(['@(x)' vectorize(s)])
f = 
    @(x)sin(x)+x.^2
>> x = linspace(0,2*pi,100);
>> plot(x,f(x))