Basic error question, The expression to the left of the equals sign is not a valid target for an assignment

I have been away from MATLAB for a few years, and I didn't realize how much I have forgotten. I dont understand where/why this error is coming from. I was just trying to make a simple example for myself but am having issues with it. "The expression to the left of the equals sign is not a valid target for an assignment" (for the '=' in the rad = xlsread row)

function  ArLLDif(rad,gr)
{

    rad = xlsread('data1.xls',1,'D3:D164');
    gr = xlsread('data1.xls','E3:E164');

    plot(rad,gr)
}

Answer 1

[the cyclist]

I would say it's the curly brackets that's causing the problem. That's not MATLAB syntax. (You have been away too long!) Try removing those and see how it goes.

[MechtEngineer]

Yes, I vote with "the cyclist" on his answer. MATLAB functions do not have curly brackets.

[Richard Brown]

As a consolation, it does look nice