nested if-else inside nested if-else

In the following program it showed error in line 22.If elseif statement can't be used in this way,please suggest alternative way.

%code

function output = blur(img,w)

img(:) = double(img(:))+1;

[row col] = size(img);

output = zeros(row, col);

for i=1:row

for j=1:col

if (i-w)<1

if (j-w)<1

A = img([1:i+w,1:j+w]);

k = mean( img ,'all');

output(i,j) = k;

elseif (j+w)>col

A = img([1:i+w,j-w:col]);

k = mean( img ,'all');

output(i,j) = k;

else

A = img([1:i+w,j-w:j+w]);

k = mean( img ,'all');

output(i,j) = k;

end

elseif (i+w)>row

if (j-w)<1

A = img([i-w:row,1:j+w]);

k = mean( img ,'all');

output(i,j) = k;

elseif (j+w)>col

A = img([i-w:row,j-w:col]);

k = mean( img ,'all');

output(i,j) = k;

else

A = img([i-w:row,j-w:j+w]);

k = mean( img ,'all');

output(i,j) = k;

end

else

if (j-w)<1

A = img([i-w:i+w,1:j+w]);

k = mean( img ,'all');

output(i,j) = k;

elseif (j+w)>col

A = img([i-w:i+w,j-w:col]);

k = mean( img ,'all');

output(i,j) = k;

else

output(i,j) = mean(img(i-w:i+w,j-w:j+w));

end

end

end

end

output(:) = uint8(round(output(:)-1));

Error: File: blur.m Line: 22 Column: 5

Illegal use of reserved keyword "elseif".

Answer 1

[DGM]

I don't have the same problem when I run it. There was some other issue though.

img = rgb2gray(imread('sources/table.jpg'));
w = 10;

img(:) = double(img(:))+1;
[row col] = size(img);
output = zeros(row, col);
for i=1:row
    for j=1:col
        if (i-w)<1
            if (j-w)<1
                % why are you calculating A, but never using it?
                A = img([1:i+w,1:j+w]);
                k = mean( img ,'all');
                output(i,j) = k;
            elseif (j+w)>col
                A = img([1:i+w,j-w:col]);
                k = mean( img ,'all');
                output(i,j) = k;
            else
                A = img([1:i+w,j-w:j+w]);
                k = mean( img ,'all');
                output(i,j) = k;
            end
        elseif (i+w)>row
            if (j-w)<1
                A = img([i-w:row,1:j+w]);
                k = mean( img ,'all');
                output(i,j) = k;
            elseif (j+w)>col
                A = img([i-w:row,j-w:col]);
                k = mean( img ,'all');
                output(i,j) = k;
            else
                A = img([i-w:row,j-w:j+w]);
                k = mean( img ,'all');
                output(i,j) = k;
            end
        else
            if (j-w)<1
                A = img([i-w:i+w,1:j+w]);
                k = mean( img ,'all');
                output(i,j) = k;
            elseif (j+w)>col
                A = img([i-w:i+w,j-w:col]);
                k = mean( img ,'all');
                output(i,j) = k;
            else
                % mean() of a 2D array is a vector
                k = img(i-w:i+w,j-w:j+w);
                output(i,j) = mean(k(:));
            end
        end
    end
end

% using (:) in this assignment screws up class inheritance
% you end up with a 'double' image with incorrectly-scaled data
output = uint8(round(output-1));

I don't know why you would be getting that error

[Kazmir Fahrier]

Sorry for being late.You are right.But I could not understand why the type conversion didn't happen

%question

% code

function output = blur(img,w)

img(:) = double(img(:))+1;

[row col] = size(img);

output = zeros(row, col);

for i=1:row

for j=1:col

if (i-w)<1

if (j-w)<1

A = img([1:i+w,1:j+w]);

k = mean(A ,'all');

output(i,j) = k;

elseif (j+w)>col

A = img([1:i+w,j-w:col]);

k = mean( A ,'all');

output(i,j) = k;

else

A = img([1:i+w,j-w:j+w]);

k = mean( A ,'all');

output(i,j) = k;

end

elseif (i+w)>row

if (j-w)<1

A = img([i-w:row,1:j+w]);

k = mean( A ,'all');

output(i,j) = k;

elseif (j+w)>col

A = img([i-w:row,j-w:col]);

k = mean( A ,'all');

output(i,j) = k;

else

A = img([i-w:row,j-w:j+w]);

k = mean( A ,'all');

output(i,j) = k;

end

else

if (j-w)<1

A = img([i-w:i+w,1:j+w]);

k = mean( A ,'all');

output(i,j) = k;

elseif (j+w)>col

A = img([i-w:i+w,j-w:col]);

k = mean( A ,'all');

output(i,j) = k;

else

A = img([i-w:i+w,j-w:j+w]);

k = mean(A, 'all');

output(i,j) = k;

end

end

end

end

output(:) = uint8(round(output(:)-1));

[Kazmir Fahrier]

I have solved it.Thank you.