pgfplotstikz-pgf
I tried the solution proposed in : How can/should I include annotated images?
However, the coordinates don't match with the coordinates I used when plotting the diagrams (data coordinates). For example, I have a mesh generated by a python program and matplotlib and I want to annotate it, using the same coordinates I used when plotting the data.
Let's say there is a node in the mesh at coordinates (2,3). I'd like to be able to annotate it using \node at (2,3) {text};
As the sample matrix datasets(131*131) are large in size LuaLaTeX -shell-escape approach was adopted and pdflatex fails due to memory limitations. I have retained the TeX memory defaults on TeXLive 2012 frozen. In view of your real datasets of size (1000x500) points. I made some points to help you.
TeX memory problems in pgfplots can be resolved by(More info at Section 6.1 pgfplots manual revision 1.8, 17/3/2013)
1)How to expand TeX's "main memory size"? (pgfplots memory overload) and How can one predict pgfplots memory overload?
2)Downsampling the data using gnuplot or sed as discussed in pgfplot: plotting a large dataset.
3)Export separate figure pdf's using pgfplots externalize library to reduce the compilation time and avoid memory problems for large documents.
4)Alternatively use fully gnuplot solution using gnuplottex package via improved terminal exports epslatex, pdf, and lua/tikz.
gnuplot lua/tikz terminal driver
"The lua terminal driver creates data intended to be further processed by a script in the lua programming language. At this point only one such lua script,
gnuplot-tikz.lua, is available. It produces a TeX document suitable for use with the latex TikZ package. Other lua scripts could be written to process the gnuplot output for use with other TeX packages, or with other non-TeX tools. set term tikz is shorthand for set term lua tikz. As decribed above, it uses the generic lua terminal and an external lua script to produce a latex document" from gnuplot 4.6 documentation
Examples:
A tikz terminal can export full-plot.tex of plot like in this TeXample.net example and gnuplottikz example
Hoping this works for you.
Using pgfplots (invoking gnuplot) and it's
groupplotlibrary. on 131*131 matrix dataset provided by OP
\documentclass[preview=true,12pt,border=2pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepgfplotslibrary{groupplots}
%\usepgfplotslibrary{external}
%\tikzexternalize% activate externalization!
% same matrix data used for all four figures for illustration
% code compiled with lualatex -shell-escape, gnuplot 4.4.3 and pgfplots 1.8
% Matrix dataset(131*131) in "mat-data.dat" (provided by OP in comment).
\begin{document}
\begin{tikzpicture}
\begin{groupplot}[view={0}{90},colorbar,colormap/bluered,colorbar style={%
ytick={-19,-18,-17,-16,-15,-14,-13,-12,-11}},label style={font=\small},group style={group size=2 by 2,horizontal sep=3cm},
height=3.5cm,width=3.5cm,footnotesize]
\nextgroupplot % First Figure
\addplot3[raw gnuplot,surf,shader=interp]
gnuplot[id={surf}]{%
set pm3d map interpolate 0,0;
splot 'mat-data.dat' matrix using 1:2:(log($3));}; %natural logarithm
\nextgroupplot % Second Figure
\addplot3[raw gnuplot,surf,shader=interp]
gnuplot[id={surf}]{%
set pm3d map interpolate 0,0;
splot 'mat-data.dat' matrix using 1:2:(log($3));};
\nextgroupplot % Third Figure
\addplot3[raw gnuplot,surf,shader=interp]
gnuplot[id={surf}]{%
set pm3d map interpolate 0,0;
splot 'mat-data.dat' matrix using 1:2:(log($3));};
\nextgroupplot % Fourth Figure
\addplot3[raw gnuplot,surf,shader=interp]
gnuplot[id={surf}]{%
set pm3d map interpolate 0,0;
splot 'mat-data.dat' matrix using 1:2:(log($3));};
\end{groupplot}
\end{tikzpicture}
\end{document}
code compiled with lualatex -shell-escape, gnuplot 4.4.3 and pgfplots 1.8
Alternative Approach(option 4 above): Using fully gnuplot based on
gnuplottexpackage
code compiled with pdflatex -shell-escape, gnuplot 4.4.3 and gnuplottex(version October 2, 2012)
\documentclass[preview=true,border=2pt]{standalone}
\usepackage{gnuplottex}
\begin{document}
\begin{gnuplot}[terminal=epslatex,terminaloptions={font ",7"}]
set tmargin 0 # set white top margin in multiplot figure
set bmargin 1 # set white bottom margin in multiplot figure
set lmargin 0
set rmargin 0
set xrange [0:130]; # x and y axis range
set yrange [0:130];
set cbrange [-19:-12]; # colorbox range
unset key; # disables plot legend or use "notitle"
set palette model RGB defined (0 '#0000B4',1 '#00FFFF',2 '#64FF00',3 '#FFFF00',4 '#FF0000',5 '#800000'); # hex colormap matching pgfplots "colormap/bluered"
set pm3d map; # `splot` for drawing palette-mapped 3d colormaps/surfaces
set pm3d interpolate 0,0; # interpolate optimal number of grid points into finer mesh, and
# color each quadrangle with 0,0
set multiplot layout 2,2 rowsfirst scale 0.9,1.2; # subplots 2 by 2
# First Figure
splot 'mat-data.dat' matrix using 1:2:(log($3)); # matrix data with log(z-axis)
# Second Figure
splot 'mat-data.dat' matrix using 1:2:(log($3));
# Third Figure
splot 'mat-data.dat' matrix using 1:2:(log($3));
# Fourth Figure
splot 'mat-data.dat' matrix using 1:2:(log($3));
unset multiplot;
\end{gnuplot}
\end{document}
Alternative Approach: Reading from
mat-data.datfile directly in pgfplots
I have failed to get result in this way. Anybody can give their feedback. \addplot3[surf,mesh/cols=131,mesh/ordering=rowwise,shader=interp] file {mat-data.dat};
You can use the nodes near coords function for that. If you add
\pgfplotsset{
nodes near coords={
\pgfmathtruncatemacro\nValue{\coordindex+1}%
$\nValue \theta$%
}
}
to your document, the node labels will be printed without you having to touch the matlab2tikz-generated code at all:
If you want to be able to provide arbitrary labels that don't directly depend on the coordinate index, you can use a PGF math array that stores the strings for the labels and access that array within the nodes near coords:
\def\labellist{{"$\sfrac{1}{2}\theta$","$\theta$","$\sfrac{3}{2}\theta$","$2\theta$"}}
\pgfplotsset{
nodes near coords={
\pgfmathparse{\labellist[\coordindex]}%
\pgfmathresult
}
}
Best Answer
If you want to refer to the axis coordinates of a pgfplots
axis, you'll need to put the TikZ commands (like\draw,\node, or\path) inside theaxisenvironment, and you'll need to use theaxis cs:coordinate system.In your example, you could say
to get