Can you hel me with my code

here is what i have

rng(123);
N=111;
noise= -1+2.*rand(N,1);
for n=1:N
    y(n) = sin(2*pi.*n./20) + 2*cos(2*pi.*n./60)+noise(n);
end
figure (1), plot(y),

which is working... now I have to take the answer of this and put it through a few functions to make it smoother. function has a few functions inside, but when i run it it does not work can some one please check it for me and if possible fix it

thank you

function y=LPF(inputData)
x=1:inputData;
for n=1:length(inputData)
    if n==1
        y(1)=(x(1)+x(2))/2; %for the first value of n      
    elseif n==inputData %for last value of n
        y(inputData)=y(inputData-1)+y(inputData)/2;
    elseif n==2 %for 2nd value 
        y(2)=(x(1)+x(2)+x(3))/3;
    elseif n==inputData-1 %for the next to last value
        y(inputData-1)=(x(inputData-2)+x(inputData-1)+x(inputData))/3;
    else
        y(n)=(x(n-2)+x(n-1)+x(n)+x(n+1)+x(n+2))/5;%for all other values of n
    end
    y=[y,x];
end

[Walter Roberson]

Please expand on "when i run it it does not work". Do you mean you encounter an error message, or it does not give the output you would like?

[Slo]

I am sorry it gives me error msg

??? Attempted to access x(3); index out of bounds because numel(x)=2.

Error in ==> LPF at 9

y(n)=(x(1)+x(2)+x(3))/3;

[Andrei Bobrov]

in your case should be inputData >= 5

[Slo]

I got it now thank you

Answer 1

[Walter Roberson]

For your code to work, inputData must be a positive integer scalar which 2 or greater.

Your code would run in to the error message you noted in the circumstance that inputData was a vector whose first element was greater than or equal to 2 but less than three, or in the circumstance that inputData was a scalar whose value was greater than (but not equal to) 2 and less than three, or in the circumstance that inputData was a vector whose first element had a value greater than (but not equal to) 2 and less than three.

If your intended input to the routine is the "y" that you calculated in your first routine, then your line

x=1:inputData;

should then instead be

x = inputData;

and every reference to inputData in the loop should be replaced with length(inputData) such as changing

elseif n==inputData

to

elseif n == length(inputData)