Function Error: Already declared

My function was working fine until I typed in clear all. Now it does not work.

I get this error message: Function 'get_portfolio_return' has already been declared within this scope.

This is my function code:

function [E_Rp, sigma_Rp] = get_portfolio_return( weight,exp_rets, vols,corr) 
E_Rp= weight.* exp_rets(1,1)+ (1-weight).*exp_rets(1,2);
sigma_Rp= sqrt((weight.^2.*vols(1).^2) + ((1-weight).^2.*vols(2).^2)+(2.*corr.*(weight)).*(1-weight).*vols(1).*vols(2));
 
end
% The stated function defines the necessary variables for subsequent
% calculations.  Expected Return is calculated as a function of weight and
% expected returns.  Weight is the weight of Asset1 and exp_rets are the
% expected returns of asset 1 and asset 2.

What caused this problem/ how do I fix it?

[Jeremy]

Did you save this as a function file separate from your main script file, or did you put it at the bottom of your script as a local function? Did you do both? How are you calling it?

Answer 1

[Chase Weinberg]

Okay, so the problem was the function name was different from what I assigned it. I did not realize the name I saved it as has to match the part after function []=

[Walter Roberson]

The rule is that if there is a difference between the file name and the name of the first function in the file, then in order to call the function, you need to use the file name.

Answer 2

[Muhammad Sinan]

When define user function in MATLAB programming then you will need the following format.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function (Dependent Variables1, 2, 3, ...) = FunctionName(Independent Variables1, 2, 3, ...)

body of function

end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

so, when you save this file then you have to use this file on the name same as the name of the function. Otherwise, the function will not work.

Example:

FunctionName.m

[Sian Evans]

My first function name and the file name are the same yet I still get this error? I don't understand how to bypass it?

[Walter Roberson]

What is the first executable word in the file? The very first thing that is not a comment?

Answer 3

[Sumanth Hegde]

I got this error because I declared the same function name twice.

[Yasmeen]

I got it too.