Question

I have been currently using a Matlab script that plots a function and prints its data into a png file, but I have a problem with this last phase.

The fact is that, moving from plotted image to png files, some data points disappear.
Here are my images.

What Matlab (correctly) plots (note that the maximum is (0; 7.7)):

And here’s what Matlab prints into the file:

Note that all the points in the Y asymptote are missing!

Why does this happen?

Here’s my code:

grafico2D('filename.dat', -1);

...

function [result] = grafico2D(filename, max_X)
% function that loads data from a two-column file and plot them in 2D image
close all;

dati = load(filename); % load data from file
X = dati(:,1); % X axis
Y = dati(:,2); % Y axis

temp = size(X);
lungX = temp(1);

hFig = figure();
set(hFig, 'Visible', 'on');

plot(X, Y, 'red'); 
hold on;
ylim([0 1]); 

if(max_X==-1) 
    xlim([1 X(lungX)]); 
else
    xlim([1 max_X]);
end

xlim

title(strrep(filename,'_','\_')); % substitute _ with \_
xlabel('annotation prediction position'), ylabel('likelihood');
grid


 print(hFig, '-dpng', filename); % stampa su file
% }

result = 1;

end

Is there someone who can help me?
Thanks!

Answer 1

You can increase the resolution of your image with the -r option which specifies the resolution in dot per inch (with 90 as default). It should solve your problem (at least it did for me). See the Matlab print function documentation.

PS: you could also use thicker lines with the line property LineWidth.