Loop to plot PDF over bar plot

I am trying to write code to plot a line from a probability density function over the bar plot from which it's derived. The data for the bar plot is stored in an matrix called gsd. The first column in the scale and columns 3:19 are data. The PDF data is stored in a matrix called deco. The labels are stored in a 1x19 cell called label. Each PDF has a different scale. When I plot them one at a time I do as follows:

 bar(gsd(:,1), gsd(:,3))
 hold on
 plot(deco(:,1), deco(:,2), 'LineWidth', 3)
xlabel ('Grain size (phi)')
ylabel ('Weight Percent')
title (label(:,3))

For each sample I change the y of the bar plot to be the next column, the x and y of the line to be the next two columns, and the title to the next column over. I'd like to do this as a loop, but I'm having trouble coding the loop to loop through 3 different matrices.

I've managed to loop making the bar plot but I can't figure out how to save the file or make the title each columns' label. I also split the deco matrix into just the scale and pdf because I couldn't figure out how to make it call two at a time from one matrix. This cycles through but it never stops and the plotted lines become increasing nonesensical. Below is my code. I'm sure some of the naming is non-standard. I'm self taught so please tell me everything I'm doing wrong so I can learn. Thanks!

for ColIdx=  3:19 % grain size data
 for i= 3:19 % gsd labels
 for j = 1:17 % pdf scale
 for k= 1:17 % pdf 
     
    xdata= gsd(:,ColIdx); % tells loop what each loop is pulling from
    qlabel= label(:, i);
    qscale= scale(:,j)
    qpdf= pdf(:,k)
    
    filename = sprintf('i_GSD.png', ColIdx); 
    
    figure;
    
    bar(gsd(:,1), xdata)
    xlabel ('Grain size (phi)');
    ylabel ('Weight Percent (%)');
    title (sprintf ('i_GSD', ColIdx));
    hold on
    
   plot( qscale, qpdf, 'LineWidth', 3)
    
    % Save the plot as a PNG file
    saveas(gcf, filename);
    
    close(figure)
 end
 end
 end
end

Answer 1

[dpb]

It would be easier to be sure we understand if you would attach a .mat file with data arrays...but, here's a stab at it...

What works for one as template--

bar(gsd(:,1), gsd(:,3))
hold on
plot(deco(:,1), deco(:,2), 'LineWidth', 3)
xlabel ('Grain size (phi)')
ylabel ('Weight Percent')
title (label(:,3))

So looping construct could be something like...

nGS=width(gsd);                         % max number in the grain size array in case changes
ixGSx=1;                                % the location of x data in case it were to change
ixGS1 = 3;                              % the first data column in case it changes, too
ixLab1 = 1;                             % index into label array for first
iX=1;                                   % first index of the X data (Y assumed next column)
for ixGS=ixGS1:nGS                      % grain size data
  hF=figure;                            % start a new figure, keep a handle
  hB=bar(gsd(:,ixGSx),gsd(:,ixGS))      % make the barplot, save handle so can decorate later if want
  hold on
  hL=plot(deco(:,iX),deco(:,iX+1),'linewidth',3);
  xlabel ('Grain size (phi)');
  ylabel ('Weight Percent (%)');
  title(label(ixGS));
  filename = sprintf('GSD_%02d.png',ixGS); % lead with alpha character and use leading zero so will sort
  saveas(hF, filename);
  close(hF)
  iX=iX+2:                              % increment pointer to deco X column for next pass...
end

I think you need only the one outer loop; the "trick" in such things is to keep other counters to increment as needed into the other arrays; don't try to do everything with just the one loop index.

I didn't try to create fake data so the above is air code/untested and undoubtedly will have issues to fix...attach some real data files and we can sort things out.

[Sophia]

That worked! Thank you!

[dpb]

Amazing! <vbg>