dimensionserrorspgfplots
I have the following pgfplots code:
\begin{tikzpicture}
\begin{axis}[domain=-8:2]
\foreach \i in {-10,-9.8,...,10} {\addplot+[smooth] {-x/\i+\i};}%
\end{axis}
\end{tikzpicture}
I need several line-plots in order for the parabolic pattern to emerge, hence the for loop with a 0.2 increment. Unfortunately, this gives me the dimension too large error. What can I do?
This happens because PGFPlots only uses one "stack" per axis: You're stacking the second confidence interval on top of the first. The easiest way to fix this is probably to use the approach described in "Is there an easy way of using line thickness as error indicator in a plot?": After plotting the first confidence interval, stack the upper bound on top again, using stack dir=minus. That way, the stack will be reset to zero, and you can draw the second confidence interval in the same fashion as the first:
\documentclass{standalone}
\usepackage{pgfplots, tikz}
\usepackage{pgfplotstable}
\pgfplotstableread{
temps y_h y_h__inf y_h__sup y_f y_f__inf y_f__sup
1 0.237340 0.135170 0.339511 0.237653 0.135482 0.339823
2 0.561320 0.422007 0.700633 0.165871 0.026558 0.305184
3 0.694760 0.534205 0.855314 0.074856 -0.085698 0.235411
4 0.728306 0.560179 0.896432 0.003361 -0.164765 0.171487
5 0.711710 0.544944 0.878477 -0.044582 -0.211349 0.122184
6 0.671241 0.511191 0.831291 -0.073347 -0.233397 0.086703
7 0.621177 0.471219 0.771135 -0.088418 -0.238376 0.061540
8 0.569354 0.431826 0.706882 -0.094382 -0.231910 0.043146
9 0.519973 0.396571 0.643376 -0.094619 -0.218022 0.028783
10 0.475121 0.366990 0.583251 -0.091467 -0.199598 0.016664
}{\table}
\begin{document}
\begin{tikzpicture}
\begin{axis}
% y_h confidence interval
\addplot [stack plots=y, fill=none, draw=none, forget plot] table [x=temps, y=y_h__inf] {\table} \closedcycle;
\addplot [stack plots=y, fill=gray!50, opacity=0.4, draw opacity=0, area legend] table [x=temps, y expr=\thisrow{y_h__sup}-\thisrow{y_h__inf}] {\table} \closedcycle;
% subtract the upper bound so our stack is back at zero
\addplot [stack plots=y, stack dir=minus, forget plot, draw=none] table [x=temps, y=y_h__sup] {\table};
% y_f confidence interval
\addplot [stack plots=y, fill=none, draw=none, forget plot] table [x=temps, y=y_f__inf] {\table} \closedcycle;
\addplot [stack plots=y, fill=gray!50, opacity=0.4, draw opacity=0, area legend] table [x=temps, y expr=\thisrow{y_f__sup}-\thisrow{y_f__inf}] {\table} \closedcycle;
% the line plots (y_h and y_f)
\addplot [stack plots=false, very thick,smooth,blue] table [x=temps, y=y_h] {\table};
\addplot [stack plots=false, very thick,smooth,blue] table [x=temps, y=y_f] {\table};
\end{axis}
\end{tikzpicture}
\end{document}
Possibly having very little steps in the x coordinates forces pgfplots to the numerical accuracy limits. Instead using the logarithmic axes for y and linear for x works without any problem.
\begin{semilogyaxis}[black,
width=14cm,
height=10cm,
mark=none,
xlabel=Scaling Factor,
transpose legend,
legend style={at={(0.5,-0.15)},anchor=north},
legend entries={MSE, Accuracy},
legend style={nodes=right}]
\addplot[no markers,blue] table [x=a, y=b, col sep=comma,] {
./chapter4/refined2b.csv
};
\addplot[no markers,red] table [x=a, y=c, col sep=comma,] {
./chapter4/refined2b.csv
};
\end{semilogyaxis}
Best Answer
Besides the obvious 1/0 division, the question is not about math but about TeX, i.e. why pgfplots fails. pgfplots probably complains because whatever internal represenation of 1/0 is "too large" to be plotted. The solution is to use
restrict y to domain(Having said that, it is anyway dangerous to allow a division by zero in general.)