How to remove zeros using Function in Matlab?

Hi Everybody,

This 1st time I used a Matlab Function, I used it to read two images (Tiff format), one of them has NaN values and 2nd image has Zeros. I want to remove NaN and Zeros rows completely. By the way the output of 1st image is fine but the problem in the output of 2nd image. I have attached the Function and Script.

Thank you in Advance

Reyadh

if true
  function [out_image] = img_read_1(input_image,no_data)
%%%out_image   ::: this is the name of your out image 
%%%input_image ::: this is the name of your input image 
%%%fname       ::: dir name
IMG_read=imread(input_image);
%image=im2single(IMG_read);
image=IMG_read;
image_reshape=reshape(image,1,size(image,1)*size(image,2));
image_t=image_reshape';
out_image=image_t;
out_image(find(out_image(:)<=no_data)) = NaN;
out_image=out_image(~isnan(out_image(:)),:);
end

Answer 1

[Guillaume]

Considering that the nans you want to remove are the ones you put there on the previous lines, why put the nans in the first place?

To remove a row where any of the value on the row satisfy a condition, you would use the any function, so:

out_image(any(isnan(out_image), 2), :) = []; %remove rows that contain any nan

But as said, there's no point putting the nans there in the first place, so:

%replace the last three lines:
out_image = image_t(all(image_t > no_data, 2)); %only keeps rows of image_t whose values are ALL greater than no_data

Finally, note that the find is completely unnecessary in the code you wrote:

   out_image(out_image <= no_data) = NaN;
   %works exactly the same as
   out_image(find(out_image <= no_data)) = NaN