how can i creat image from data?

hi I'm beginner in matlab my problem is how to get image.i have text data (row,col) and i want to create image from this data, and this image should be like fringes (dark and white line)

[KSSV]

Attach the data here....

Answer 1

[Farouk Moukaddem]

Hi,

Refer to the following documentation link for the "mat2gray" command that is used to convert a matrix to a grayscale image:

http://www.mathworks.com/help/images/ref/mat2gray.html

You will also find an example in the above link that will help you get started with Image Processing applications.

Best,

Farouk

[Sanaa]

Hi sir Thanks for replying but I have data not image according to your link I should read the image for my case I didn't have ,I got results and that's results is text file contain four cols (r,theta,phi,intensity) and I should generate image like sphere (like ball) Thanks

Answer 2

[Image Analyst]

Try this (untested):

% In advance, read your text data into three vectors,
% rows and columns and grayLevels.  Then...
lastRow = max(rows);
lastCol = max(columns);
grayImage = zeros(lastRow, lastCol, 'uint8');
for k = 1 : length(rows)
    grayImage(rows(k), columns(k)) = grayLevels(k);
end

This assumes that rows and columns are integers.

[Sanaa]

hi i read my data like this and this is my code

clc
clear;

fid = fopen('fort (1).130');
tline = fgets(fid);
out=[];
while ischar(tline)
    a=sscanf(tline,'  The Time-averaged Poyntine vector(W/m*m) at point:    %f');
    tline = fgets(fid);
    [b c]=sscanf(tline,'%f %f');
    tline = fgets(fid);
    [d]=sscanf(tline,' Psca  %f');
    tline = fgets(fid);

      out=[out;a b(1) b(2) d];
  end

fclose(fid);

% load ('out.mat')
r= out(:,1);
theta= out(:,2);
phi= out(:,3);
I= out(:,4);
theta_new=theta.*180./pi;

r_new=ones(size(theta_new));
[X,Y] = meshgrid(theta_new,phi);
[X,Y,Z]=sph2cart(theta_new,phi,r_new);

%  tri = delaunay(x,y);
%    trisurf(tri,x,y,z)
surf(X,Y,Z,I);

[Image Analyst]

There is no question in your response. Should there be? Or did I answer your question successfully?

In the meantime, read this link: http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup#answer_18099

And THIS LINK and attach your data file if you want us to try to run your code.

[Sanaa]

I tried also this code but it isn't work,

    clc
  clear;

fid = fopen('fort (1).130');
tline = fgets(fid);
out=[];
while ischar(tline)
    a=sscanf(tline,'  The Time-averaged Poyntine vector(W/m*m) at point:    %f');
    tline = fgets(fid);
    [b c]=sscanf(tline,'%f %f');
    tline = fgets(fid);
    [d]=sscanf(tline,' Psca  %f');
    tline = fgets(fid);

      out=[out;a b(1) b(2) d];
  end

fclose(fid);

% load ('out.mat')
r= out(:,1);
theta= out(:,2);
phi= out(:,3);
I= out(:,4);
theta_new=theta.*180./pi;

for i=1:length(theta_new)
    r_a=r(i);
    theta_new_a=theta_new(i);
    phi_a=phi(i);

     x = r(i) .* cos(phi(i)) .* cos(theta_new(i));
     y = r(i) .* cos(phi(i)) .* sin(theta_new(i));
  %    z = r_a .* sin(phi_a);
     I(x,y)=I(i);

% x  =  rcosthetasinphi  
% y  =  rsinthetasinphi  
% z  =  rcosphi.
%     
%     
end 

I=uint8(I);
 imshow(I)

[Image Analyst]

I think you overlooked the last line of my answer. Here it is again:

And THIS LINK and attach your data file if you want us to try to run your code.

Not really sure why you did not attach your data -- did you just forget, or am I to just assume that you don't want us to run your code with your data?