Loop code for images with x1, y1, z1 variables

hi all. i cannot solve this issue. briefly, i have a code for image manipulation, however i cannot solve putting it into a loop. for 7 photos in the images folder, i want to read it one by one and after manipulation i want to store the outputs in x1,x2,...x7 , y1,y2,...y7 , z1,z2,...z7. significant part of the code can be seen below.

thank you so much in advance.

for k=1:7

      i  = imread(sprintf('images/a%d.jpg',k));

.....

im = rgb2gray(i);

....

eval(['x' num2str(i)='double(im)']);

eval(['y' num2str(i)='x(:)']);

eval(['z' num2str(i)='hist(y)']);

end

....

i have also tried the code below with sprintf instead of num2str and yet it haven't worked either.

eval(sprintf('x%d = double(im)', i));

eval(sprintf('y%d = x%d(:)', i));

eval(sprintf('z%d = hist(y%d)', i));

Answer 1

[Image Analyst]

i has not been defined yet when you did:

i  = imread(sprintf('images/a%d.jpg',i));

perhaps you meant

rgbImage  = imread(sprintf('images/a%d.jpg', k));

Please see the FAQ for code samples: http://matlab.wikia.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F

[Adelante]

sorry i've misspelled it . in my code, correct line is:

i = imread(sprintf('images/a%d.jpg',k));

the main problem is in the loop.thank you

[Image Analyst]

You don't want to create variables z1, z2, etc. See the FAQ: http://matlab.wikia.com/wiki/FAQ#How_can_I_create_variables_A1.2C_A2.2C....2CA10_in_a_loop.3F Make an array instead. You also don't need to use eval() - I never ever use it or need to.