I want to use gptoolbox package in Matlab. but I can not find these (mesh grid, Parameterization QuadCover).what should I do?
this page (https://github.com/alecjacobson/gptoolbox_ext) doesn't work.
is there any alternative package for gptoolbox?
Thanks,
Related
I have Matlab code that produces an array of subplots that looks like this:
When I save this as an EMF file (normally a vector format) and insert in Powerpoint or view with Inkscape, then zoom in closely on the image, it looks pixelated, and clearly made up of a single encapsulated object as opposed to many small graphical objects:
This is very surprising to me, as I have for a long time been exporting Matlab plots as EMF and integrating those into Powerpoint slides, in order to build there more complex graphs that, as vector graphics, would print well at any size. These imported EMFs would also scale well and look smooth regardless of how much I zoomed into them in Powerpoint.
Can anyone guess why it is that on this occasion, this plot is not saved as a vector graphics but is instead (as it seems) rendered as raster? The code that produces this figure (based on the Matlab commands subplot, line, and scatter) is rather long/inelegant, but I can give details or simplify, if required to find a solution. Thanks!
Other similar threads on this site have not helped fix this.
I believe I have encountered this issue before. If it is the same as the issue I was facing, it is to do with the renderer being used to save the plot. Although it should automatically select the painters renderer when exporting to vector files, I have had instances where it used the openGL renderer instead, which results in bitmaps being used. I'm not entirely sure why this happens -- it might be the case that for particularly complicated figures, it reverts to openGL to avoid obnoxiously large or complicated vector files.
If you are using the print command, you can force it to use the painters algorithm as follows:
print('-painters',...)
if you're saving using File>Save As..., I believe setting the renderer for the figure should work:
set(figure_handle,'renderer','painters');
For explanation, per the MATLAB documentation:
-opengl' — OpenGL renderer. Use this renderer when saving bitmap images. OpenGL produces a bitmap image even with vector formats, which might limit the extent to which you can edit the image in other applications.
'-painters' — Painters renderer. Use this renderer when saving vector graphics files. If you save to a vector graphics file and if the figure RendererMode property is set to 'auto', then print automatically attempts to use the Painters renderer. If you want to ensure that your output format is a true vector graphics file, then specify the Painters renderer. For example:
print('-painters','-deps','myVectorFile')
If you do not specify the renderer, then print automatically uses the appropriate renderer to produce the output format requested. However, if you set the Renderer property for the figure, then print uses that renderer when generating output.
EDIT: Another option is to use the Copy Figure command (Edit > Copy Figure) -- this should copy the figure as an EMF file, and should obey the figure's renderer settings.
I want to do some image OCR with PyTesseract, and I've seen that OpenCV's erode and dilate functions are very useful for noise removal pre-processing.
Since PyTesseract already requires PIL/Pillow, I'd like to do the noise removal in PIL, rather than get another library. Is there an equivalent to erode/dilate in PIL? (My research seems to suggest that MaxFilter and MinFilter could be used this way, but it's not fully clear to me if that's really true.)
Thanks!
The best option is to use OpenCV python bindings. However, if you want to use PIL/Pillow, there is the ImageFilter Module:
http://pillow.readthedocs.io/en/3.1.x/reference/ImageFilter.html
dilation_img = src_img.filter(ImageFilter.MaxFilter(3))
erosion_img = src_img.filter(ImageFilter.MinFilter(3))
The number 3 in the example is the mask size;
I need some to produce some publication-quality figures. I first export the figures from matlab in .svg format, and then I do some post-processing in inkscape. I am no problem with figures generated using plot or scatter, but when I export figures generated using surf (in view(2)), I run into problems. If I use plot or scatter, I am able to ungroup and process various parts like the title, axes, scattered points, lines, etc. in inkscape. For surf, however, matlab just exports one single figures with all various parts grouped into one single unit. I can't separate individual part, and when I zoom very close I can actually see the bitmap resolution for the axes and titles (if I use plot, the titles and axes have 'infinite' resolution when I zoom very close). I am fine with the surface plot having finite resolution, but I need to at least be able to process the axes and titles (which I currently cannot do). What should I do so that I can 'separate' the title and axes from the main plot, just like figures generated from plot and scatter?
I stumbled across this question, since I encountered the same problem.
As mentioned by #vindarmagnus, it is possible to use tikz and get rather nice results. However, tikz experiences problems with large data sets in my experience as present when using surf etc..
Solution, that worked for me:
Change the renderer to painters and the exported .svg file will retain its vectorgraphic properties when opened e.g. in inkscape:
figure('Renderer','Painters');
I used to use Inkscape for my scientific publications as well, but I found that a lot of the time you can get better results with pgfplots in latex, together with the matlab2tikz matlabscript. There’s a ton of resources about this online, but here’s how my workflow would look adopted to your surf situation. I have macOSX with latex, matlab and matlab2tikz installed. Will work with little to no modifications on linux.
In Matlab:
surf(peaks(25))
matlab2tikz('plot.tikz’)
Then I have the following bash-script (just a script in the same folder as the image, which is executed by mere double-click). (Needs to be chmod-ed as an executable for that).
#!/bin/bash
cd ~/Desktop
rm *.eps
cat > plot.tex << EOF
\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{max space between ticks=50}
\pgfplotsset{scaled ticks = false}
\pgfplotsset{compat=1.6}
\pgfplotsset{xticklabel style={/pgf/number format/fixed}}
\pgfplotsset{yticklabel style={/pgf/number format/fixed}}
\begin{document}
\input{plot.tikz}
\end{document}
EOF
pdflatex plot.tex
pdf2ps plot.pdf
ps2eps plot.ps
Note that the row cd ~/Desktop above should be changed as to reflect which folder the script is supposed to be run from (a bit crappy, but needed since Finder doesn’t properly pass along the folder from a program is executed, afaik).
This yields high-quality images in eps or pdf or what you like, with a ton of settings for axes and ticks etc. And it all uses native latex fonts.
Edit:
Recently I’ve begun to use patch() in matlab and then export it to tikz in the same manner as above, with great results. That’s another suggestion!
You can use also:
set(gcf,'Renderer','Painters')
I am desiging a simple GUI application in Matlab using GUIDE.
I am displayed a number of axis - and I would like to add some simple design elements to make the interface clearer. I would like to draw a colored rectangle around an axis (seperate from the axis)... there are two such axes, each displaying details of some things shown in a third plot, and I would like this color clue to link the details to the overview.
So is it possible to add simple geometric shape objects to a Matlab GUI? I don't see anything but controls in GUIDE but perhaps its possible to add them manually with an explicit command?
It is generally difficult to draw any random shape. Except Square & rectangle, for which you can create panels and change the properties like BorderWidth and HighlightColor.
Since MATLAB GUI is based on Java, you can create any object in MATLAB GUI which can be created in Java. You can refer to this website [1] for further learning.
[1] http://undocumentedmatlab.com/matlab-java-book/
My question is that how do I change the polygons of a map from shp file (shapefile) while using matlab. I was doing this project where i was given map in shpfile format that I need to use on, I am able to read the map in matlab but the map is divide in regions and each regions have its color, my problem I met was to change the polygons to its respective colors, anyone sees this please kindly help and reply me asap.
Are you using the Mapping Toolbox by The MathWorks, or third-party codes such as ones from the Shapefile C Library to import the shapefile? If you are using the Mapping Toolbox, I cannot be of much help here as I do not have that toolbox -- hopefully, someone else can help here.
In any case, if you could import the shapefile on to your MATLAB Workspace, you should be able to find the vector data (polygons and attributes data, etc.) somewhere...
If you do not see anything on the Workspace, possibly you can find those data in the Figure (or in the Axis).
data=get(the_handle);
I would look for the data there.
After you obtain the polygon and properties data, you can patch/fill them with any color you like (based on any other information you find there.)
Good Luck