Why Does My Matlab Function Say Input Argument 'u' is Undefined?

[shaqdiesel]

need urgent help

I'm a beginner using matlab, I saw this function working:

function une=coloca(u)
num=1:256;
val=288-(u*3000);
une(1,:)=val;
une(2,:)=num;

but when I try to use it, this error appears:

? Input argument "u" is undefined.

Error in ==> une at 3
val=288-(u*3000);

What could be the problem? Could someone help me ?

 

[thofer]

How do you call the function?