%% Print an image in PDF with custom ppi with white background
function writePDF1000ppi(figNo, numericFontSize, axesFontSize, xlab, ylab, fileName)
%make the font smaller
set(gca,'fontsize',numericFontSize-10);
set(xlab,'fontsize',axesFontSize-10);
set(ylab,'fontsize',axesFontSize-10);
%make the backgroung white
set(figNo,'color','w');
%get figure size
set(gca,'units','centimeters');
op = get(gca,'OuterPosition');
%create a page the same size as the figure
set(gcf, 'PaperUnits','centimeters');
set(gcf, 'PaperSize', [op(3) op(4)]);
%locate the figure in the page
set(gcf, 'PaperPositionMode', 'manual');
set(gcf, 'PaperPosition',[0 0 op(3) op(4)]);
%print in PDF with resolution of 600ppi
print(gcf, '-dpdf', '-r1000', fileName)