%% Creating high-quality graphics in MATLAB for papers and presentations % * , Sandia National Laboratories (*) % * , Purdue University % * April 2013 % % (*) Sandia National Laboratories is a multi-program laboratory managed % and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed % Martin Corporation, for the U.S. Department of Energy's National Nuclear % Security Administration under contract DE-AC04-94AL85000. %% A simple figure that is hard to view % Here we show a normal image from MATLAB. % This example has been adapted from YAGTOM % (http://code.google.com/p/yagtom/), an excellent MATLAB resource. % f = @(x) x.^2; g = @(x) 5*sin(x)+5; dmn = -pi:0.001:pi; xeq = dmn(abs(f(dmn) - g(dmn)) < 0.002); figure(1); plot(dmn,f(dmn),'b-',dmn,g(dmn),'r--',xeq,f(xeq),'g*'); xlim([-pi pi]); legend('f(x)', 'g(x)', 'f(x)=g(x)', 'Location', 'SouthEast'); xlabel('x'); title('Example Figure'); print('example', '-dpng', '-r300'); %<-Save as PNG with 300 DPI %% % The default MATLAB figure does not render well for papers or slides. For % instance, suppose we resize the image to 300 pixels high and display in % HTML using the following HTML code: % %

% % The image renders as shown below and is not easy to read. % % %

% % %% Step 1: Choose parameters (line width, font size, picture size, etc.) % There are a few parameters that can be used to modify a figure so that it % prints or displays well. In the table below, we give some suggested % values for papers and presentations. Typically, some trial and error is % needed to find values that work well for a particular scenario. It's a % good idea to test the final version in its final place (e.g., as a figure % in a LaTeX report or an image in a PowerPoint presentation) to make sure % the sizes are acceptable. % % % % % % % % % % %

	Default	Paper	Presentation
Width	5.6	varies	varies
Height	4.2	varies	varies
AxesLineWidth	0.5	0.75	1
FontSize	10	8	14
LineWidth	0.5	1.5	2
MarkerSize	6	8	12

% % % Defaults for this blog post width = 3; % Width in inches height = 3; % Height in inches alw = 0.75; % AxesLineWidth fsz = 11; % Fontsize lw = 1.5; % LineWidth msz = 8; % MarkerSize %% Step 2: Creating a figure with manually modified properties % Create a new figure. Set its size via the 'Position' setting. These % commands assume 100 dpi for the sake of on-screen viewing, but this does % not impact the resolution of the saved image. For the current axes, set % the default fontsize and axes linewidth (different from the plot % linewidth). For plotting the results, manually specify the line width and % marker sizes as part of the |plot| command itself. The font size for the % legend, axes lables, and title are inherited from the settings for the % current axes. figure(2); pos = get(gcf, 'Position'); set(gcf, 'Position', [pos(1) pos(2) width*100, height*100]); %<- Set size set(gca, 'FontSize', fsz, 'LineWidth', alw); %<- Set properties plot(dmn,f(dmn),'b-',dmn, g(dmn),'r--',xeq,f(xeq),'g*','LineWidth',lw,'MarkerSize',msz); %<- Specify plot properites xlim([-pi pi]); legend('f(x)', 'g(x)', 'f(x)=g(x)', 'Location', 'SouthEast'); xlabel('x'); title('Improved Example Figure'); %% Step 3: Save the figure to a file and view the final results % Now that you've created this fantastic figure, you want to save it to % file. There are two caveats: % % # Depending on the size of figure, MATLAB may or may not choose tick % marks to your liking. These can change _again_ when the figure is % saved. Therefore, it's best to manually specify the tick marks so that % they are correctly preserved in both display and saving. % # The size needs to be preserved in the saved (i.e., printed) version. To % do this, we have so specify the correct position on the paper. % % Set Tick Marks set(gca,'XTick',-3:3); set(gca,'YTick',0:10); % Here we preserve the size of the image when we save it. set(gcf,'InvertHardcopy','on'); set(gcf,'PaperUnits', 'inches'); papersize = get(gcf, 'PaperSize'); left = (papersize(1)- width)/2; bottom = (papersize(2)- height)/2; myfiguresize = [left, bottom, width, height]; set(gcf,'PaperPosition', myfiguresize); % Save the file as PNG print('improvedExample','-dpng','-r300'); %% EPS versus PNG % An interesting feature of MATLAB is that the rendering in EPS is not the % same as in PNG. To illustrate the point, we save the image as EPS, % convert it to PNG, and then show it here. The EPS version is cropped % differently. Additionally, the dashed line looks more like the original % image in the EPS version than in the PNG version. print('improvedExample','-depsc2','-r300'); if ispc % Use Windows ghostscript call system('gswin64c -o -q -sDEVICE=png256 -dEPSCrop -r300 -oimprovedExample_eps.png improvedExample.eps'); else % Use Unix/OSX ghostscript call system('gs -o -q -sDEVICE=png256 -dEPSCrop -r300 -oimprovedExample_eps.png improvedExample.eps'); end %% % % % % % %

Original

Improved

Improved EPS->PNG

% % %% Automating the example % There is a way to make this process easier, especially if you are % generating many figures that will have the same settings. It involves % changing Matlab's default settings for the current session. Note that % these changes apply only a per-session basis; if you restart Matlab, % these changes are forgotten! % Recently, the Undocumented Matlab Blog had a great post about these % hidden defaults % . % There are many other properties that can potentially be changed as well. % The new defaults will not take effect if there are any open figures. To % use them, we close all figures, and then repeat the first example. close all; % The properties we've been using in the figures set(0,'defaultLineLineWidth',lw); % set the default line width to lw set(0,'defaultLineMarkerSize',msz); % set the default line marker size to msz set(0,'defaultLineLineWidth',lw); % set the default line width to lw set(0,'defaultLineMarkerSize',msz); % set the default line marker size to msz % Set the default Size for display defpos = get(0,'defaultFigurePosition'); set(0,'defaultFigurePosition', [defpos(1) defpos(2) width*100, height*100]); % Set the defaults for saving/printing to a file set(0,'defaultFigureInvertHardcopy','on'); % This is the default anyway set(0,'defaultFigurePaperUnits','inches'); % This is the default anyway defsize = get(gcf, 'PaperSize'); left = (defsize(1)- width)/2; bottom = (defsize(2)- height)/2; defsize = [left, bottom, width, height]; set(0, 'defaultFigurePaperPosition', defsize); % Now we repeat the first example but do not need to include anything % special beyond manually specifying the tick marks. figure(1); clf; plot(dmn,f(dmn),'b-',dmn,g(dmn),'r--',xeq,f(xeq),'g*'); xlim([-pi pi]); legend('f(x)', 'g(x)', 'f(x)=g(x)', 'Location', 'SouthEast'); xlabel('x'); title('Automatic Example Figure'); set(gca,'XTick',-3:3); %<- Still need to manually specific tick marks set(gca,'YTick',0:10); %<- Still need to manually specific tick marks %% % And here is the saved version rendered via the HTML command % %

% print('autoExample', '-dpng', '-r300'); %% % % %

% %