Implement the following formula

How can I implement the following formula? Please write the code for it. Thanks.

y[n,m]= 1/3( x[n,m−1] + x[n,m] + x[n,m+1] )

Answer 1

[Image Analyst]

kernel = [1,1,1]/3;
y = conv(x, kernel, 'same'); % Convolution does that.  All rows, one row at a time.

or

y(n, :) = movmean(x(n, :), 3); % For the nth row only.

[Sarah Maas]

I think the second one would work. However I'm using this for a grayscale image which I've converted to a matrix of values between 0 and 1.

And n and m are the independent variables (integer indices) indexing the pixels (matrix elements) along the vertical and horizontal dimensions of the image, respectively. Which i have obtained using the following (suppose A is the matrix):

n = size(A, 1);
m = size(A, 2);

How can I use this to define y and x for the equation above?

I suppose y can be:

y = zeros(n, m, 'logical');

But what about x? And is this approach correct?

[Image Analyst]

Do you want to blur all the rows with a 1-by-3 array? If so you can use conv2 or imfilter

kernel = [1,1,1]/3;
y = conv(grayImage, kernel, 'same'); % Convolution does that.  All rows, one row at a time.
y = imfilter(grayImage, kernel)

Or do you want to blur just the nth row and leave the other rows unchanged?

Answer 2

[Alan Stevens]

Change the square brackets, [ ], to curved brackets, ( ). Put a multiply sign, *, after the 3.

[Sarah Maas]

No, I need it in a sort of a for loop for each M

[Image Analyst]

OK, if you don't know how to do a for loop, then you have not even taken the most basic training on MATLAB. So follow this link and learn how to do simple things like for loops, if statements, assignments, referencing elements in an array, etc.:

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