Is EPS image editable - matlab

I converted a matlab fig to eps, I need to add the grid to this figure which now I have in eps format. Is there any possibility. I know I can change the title or labels using ultraedit or similar programs but cant identify the relevant place for grid.

Yes, you simply need to read the PostScript program and then modify it to be suitable for your needs.
You will, however, probably need a working knowledge of the PostScript language in order to understand the program and succesfully modify it.

Related

Matlab figure saved as .eps appears in 'horizontal sections' when opened in Adobe Illustrator

I normally save my matlab figures as .eps and then make them better looking using Adobe Illustrator. This works for most figures but not all.
For example I plotted my data using the violin.m function from file exchange. When I save it as .eps and open it in Illustrator, I don't get an editable figure as I usually do. Instead, My figure appears chopped in horizontal sections, and all I can do is delete them (like in the figure below).
Is there anything I can do in either matlab or Illustrator to be able to edit the figure?
I don't need an .eps file, I just need to be able to edit it.
EDITS:
I tried #MattSchmatt's suggestion of using the print2eps function but I had the same problem.
Saving as .pdf doesn't solve the problem, because the image I get is not editable in Illustrator (plus, I also get the horizontal 'chunks').
A minimal, complete and verifiable example requires matlab, the violin function linked above and illustrator. But if it helps, here's the matlab code to produce a similar figure. I save by clicking on Figure -> save as. (But as I said above I tried the print2eps function and that was the same).
X = rand(100,6);
figure; violin(X)
I tried the following, didn't work either.
set(gcf, 'Renderer', 'painters')
As the author of the question suggests, I also wasn't able to export an editable (vectorized) .eps file into Illustrator. However, exporting it as .pdf does the trick. The 'fill' for the violin plots is weird, though, and has horizontal sections (perhaps something to do with the way the density estimate is being plotted?) all over. I was able to fix this and make the plots normal (with solid filled shades): select all the horizontal sections/chunks using the magic wand tool, and then increase opacity to 100% (it is set to 50 based on the exported file). Once all the required edits are made, export the file as .tiff and it seems to look fine. Hope this replicates, and thus helps! (my MATLAB version is 2016, and Illustrator version is the CS5)

Matlab imwrite() quality

I'm very new to Matlab, though I know a few other programming languages, so please forgive me if this is something simple. I have not been able to find any answers to this, either on StackOverflow or elsewhere.
I produce a figure using the following code:
figure(6),imageplot(P); drawnow;
Which looks like this:
I then save this image to my computer using the following commands:
imwrite(P, 'images/plot.png');
And the resulting image is tiny, and missing some of the color information:
If, however, I utilize the save function in the open figure (image #1) and save it manually, I get exactly what I want, which is that exact image stored on my computer.
How would I program that? I assumed that imwrite() would just write the image directly, but apparently I'm doing something wrong. Any advice? Perhaps it has something to do with the imageplot command? I cannot seem to get that to work in imwrite.
Update: Based on the comments below, I have begun using "imresize" with the "nearest" option. This scales the image properly, but the resulting image is still curiously darker (and therefore has less information) than if I hit the "save" button in the figure.
Image saved from figure:
Image using "imresize" with "nearest" option:
The MATLAB imwrite command saves exactly the number of pixels as specified in your image matrix. This is the actual result of your computation; the reason the output is "tiny" is because it is supposed to be. To make it larger, would be to simply scale/zoom it as required.
The save figure option however does something quite different: it rasterizes the the output you obtain in the figure window and gives you the option for saving it as an image. This is evident in the fact that when you do so, you obtain a white background in addition to your result which is really just the grey background you see before you save it; this can be adjusted by resizing the figure window before utilizing the save option.
If you're looking to simply make the output figure larger, I would recommend using something along the lines of the imresize command.
Say, if you want the default size to be twice the size of the real result, simply use:
imresize(P, 2.0);
For more options, try help imresize.
The command you need for the "Save As..." functionality of figures is called "print". I often use
print(gcf, '-dpng', 'some_filename.png')
or
print(gcf, '-depsc', 'some_filename.eps','-r0')
to save a figure as it is shown on screen. The format png offers a small filesize and excellent quality, and it is understood by most image viewers and browsers. The eps format is a vector format, which I use for printig. The '-r0' option specifies "use the same size as given by the screen resolution" for the vector format properties.

Is it possible to get around MATLAB's limitation on font embedding in vector format files?

According to the MATLAB manual, when you save a figure using print or by choosing file|save, if you choose the painters renderer and save to PDF or EPS vector formats, all fonts get substituted. Is there a way to get around this limitation?
Whenever I output a figure, whether I use print or export_fig, the fonts get substituted, and so they no longer match the fonts in the document that I plan on putting the figure into. I would prefer to keep them in a vector format, because I use LaTeX and so I want to be able to use the same figures in my documents as in my beamer presentations and have them scale nicely without bloating the file size.
If I'm reading that link correctly, not all fonts get substituted. From 'Choosing a Printer Driver':
The table below lists the fonts supported by the MATLAB PostScript and Ghostscript drivers when generated with the Painters renderer (fully vectorized output). This same set of fonts is supported on both Windows and UNIX:
AvantGarde
Helvetica-Narrow
Times-Roman
Bookman
NewCenturySchlbk
ZapfChancery
Courier
Palatino
ZapfDingbats
Helvetica
Symbol
So, if you use one of the above fonts, the output vector-format figure should maintain the correct font. See for example:
list_fonts = listfonts
figure('renderer','painters'),
plot(peaks),
xlabel('this font is Helvetica','fontname','Helvetica','fontsize',24)
set(gcf,'paperpositionmode','auto')
print(gcf,'-depsc2','test1.eps')
Which produces:
So, choose one of the fonts from the list above, and the font will be output correctly. Otherwise, change the font in your presentation to match one of the above fonts.
I also encountered this problem for many times, and I have an simple but effective way that never fails me (on Windows, need GSview).
1) save fig as PDF
2) save PDF as ps
3) open ps with GSview, then click "File->PS to EPS", specify a file name and done.
Hope this helps.

Add text to PDF

I've got an exported version of a MATLAB diagram, similar to the one below. The problem is, that there are no axis captions. It's not possible to export the file again from MATLAB. I need to edit the PDF programmatically and edit about 100 diagrams, all with the same axis positions.
Is there a clean and fast way to paste the Strings X and Y at the corresponding positions in the pdf based on a batch process?
Create a PDF file with the captions. Add that as a background with to the PDF files with pdftk.
if know how to use LaTeX, the pstool package can bring you far on this on, including replacing labels (or actually any text on an eps figure) with TeX symbolic expressions. Neat if you're already working in LaTeX.

MATLAB and high quality EPS figures

I am looking to export my MATLAB plot as a high quality figure. Specifically, I would like to save it as a vector based file format such as EPS or SVG.
I have tried print and saveas commands:
saveas(h,'myFileName','epsc2');
print('-r150','-depsc2', 'myFilename');
On all occasions this produces poor quality parts of the graph, although the axis-labels are indeed vector. Why does MatLab do some horrible rendering before putting it into an EPS?
Example of poor quality plot here:
http://users.ox.ac.uk/~pemb2372/myFileName.eps
Edit:
It is also worth noting that if you use a Mac viewing an EPS file from Matlab, 'Preview' app may render inner graph content rasterized and poor quality, while leaving the axis and labels vectorized and high quality. This is very misleading but when you open said EPS file in, for example, Inkscape, the quality is actually vector and quite high.
Edit 2:
My university hosting account has expired, so you can no longer view the figure. Suffice it to say that it showed a poor quality raster-style plot within high quality beautiful axis lines, ticks and labels.
I thought I would share the issue I had, and how I overcame it...
I was getting terrible results because I had the wrong renderer set to default. In my startup.m, I had the zbuffer renderer enabled. This is an example eps output.
I made that eps output with: print(gcf,'-depsc2','filename.eps'). This eps is so OBVIOUSLY rasterised. It makes me angry at matlab. Then, I had a brainwave - perhaps my default renderer zbuffer is interfering with the image save process. So, adding the line:
set(gcf,'renderer','painters')
and running the print command as before, here is the output:
Note that I just took screenshots of the eps output files at 100%. And I can confirm the second image is actually vector. Here is a good question/explanation on choosing Renderers in MATLAB.
Matlab can export to pdf with better quality than EPS, but with its own caveats of setting decent margins and font sizes.
edit:
Examples are similar to the EPS case as explained in the help of e.g. print:
saveas(gcf,'filename.pdf')
or
print('-dpdf','filename.pdf')
You might also want to take a look at the PaperSize, PaperPosition and PaperUnits properties of your figure (by means of the set and get functions).
edit: Another option is to use one of the functions available on FileExchange such as the ones mentioned by #user664303 below. My personal favorite for use with LaTeX is matlab2tikz for which the latest version can be gotten from GitHub. Together with the external library of TikZ, I think this delivers some of the most nicest graphs around.
Probably it's also best to mention that I have been actively involved in the matlab2tikz project since 2012.
The export_fig function on the MATLAB file exchange is a reasonably reliable way of accurately exporting figures to eps and pdf (as well as bitmap formats) in MATLAB.
The plot2svg function, also from the file exchange, allows you to export in svg format. It provides some additional benefits, such as being able to export translucent patch objects in vector format.
A comparison of exporting methods is given in this blog post.
I always acquire the final plots (those which are supposed to be inserted into papers and publications) by matplotlib library of python.
You can bet on the amazing quality of the generated plots, both .pdf and .eps formats.