Error While Saving the Raw data into Binary Image.

Hello Everyone, I hope you are doing well. I have the code which make the data into Image format.

But the main issue with this code is that, When the same values of data comes it gives the error here is the error.

As i attached the 2 dataset below. The code works fine on dataset2.mat

While when we run it into dataset1.mat it gives the error.

Error using matlab.internal.math.interp1

Sample points must be unique.

Error in interp1 (line 188)

VqLite = matlab.internal.math.interp1(X,V,method,method,Xqcol);

The following is the code which i used

[numImages, lenImage] = size(Dataset1000);
                            % ImageSize
for imNum = 1:numImages        
    imData = Dataset1000(imNum,:);  % get pattern
    
    dataset=imData;
    x=1:numel(dataset);%this is what you did implictly
    y=dataset;
    resolution=1000;
    X=linspace(min(x), max(x) ,resolution);
    Y=linspace(min(y), max(y) ,resolution);
    % determine index in X of each x, likewise for y (note that the coordinates
    % are flipped for the y-direction in images).
    ind_x=interp1(X,  1:numel(X) ,x,'nearest');
    ind_y=interp1(Y,numel(Y):-1:1,y,'nearest');
    %compute linear index
    ind=sub2ind([resolution resolution],ind_y,ind_x);
    % create the image
    IM=zeros(resolution,resolution);
    IM(ind)=1;
    % Since you apparently want a dilation, apply it before displaying the
    % image.
    SE=strel('disk',2);
    im=imdilate(IM,SE);

end

Answer 1

[Walter Roberson]

We talked to you about this already. Your min x and max x are the same so your linspace is all the same value.

There is no way to rescue the situation with a small code tweak. You need to go back and rethink what you are doing.

Have you considered using improfile()? It automatically switches between interpolation over x or over y to get the best results.

[Stephen john]

@Walter Roberson i have tried improfile() But it does not work.

Is there is any other solution to solve this problem. I am kind of stuck in this for long time

[Stephen john]

@Walter Roberson How to use improfile in above code?

[Walter Roberson]

No, sorry, you will need to give up on the task as you have currently defined it.

You are trying to ask the question "what is the unique y value for this x value", and that is going to fail for vertical lines, as such lines have several simultaneous y values for some x value. So you need to not ask that question at least for vertical lines. It probably is not a great idea to ask that question for lines that are almost vertical, such as a one pixel change in x and a 400 pixel change in y.

improfile does 2d interpolation between two endpoints, returning the interpolated values and also the x and y coordinates interpolated at. It automatically chooses whether to increment along x or along y to give the best results.

[Stephen john]

@Walter Roberson Okay So we will drop this code.. Then How can i do the same task with any other code?

Can you please share any code for this?

[Walter Roberson]

To draw lines into an array use Computer Vision insertShape() or use the File Exchange contributions for Breshenham's Line Algorithm

[Stephen john]

@Walter Roberson But it only draw a line not plot the other shapes

[Stephen john]

@Walter Roberson Can you please help me with this?

[Walter Roberson]

Computer Vision has insertShape and insertText. Between the two they can create any line graph (surfaces are harder)