# pgfplots: How to ignore the last line of a data file?

I need to plot data files which contain a comment in the last line, like this:

0  2  4
1  5  7
2  9  5
3 11  15
4 10  15
THIS WAS: TOTAL


Now, pgfplots seems to have a problem with that giving me an error message complaining about an unbalanced number of columns.

My question is: How do I tell pgfplots to ignore the last row of the data file? (I know about the skip first option of pgfplotstable. Maybe there is an equivalent for the last row that I just couldn't find in the manual.)

MWE:

\documentclass{standalone}

\usepackage{pgfplots}

\usepackage{filecontents}

\begin{filecontents}{total.dos}
0  2  4
1  5  7
2  9  5
3 11  15
4 10  15
THIS WAS: TOTAL
\end{filecontents}

\begin{document}
\begin{tikzpicture}
\begin{axis}
\addplot [no markers, red] table [x=0, y=1] {\total}; \addlegendentry{$1$}
\addplot [no markers, blue] table [x=0, y=2] {\total}; \addlegendentry{$2$}

\end{axis}
\end{tikzpicture}
\end{document}

-

The simplest way of doing this is by adding additional line comment characters. For example:

\pgfplotstableread[comment chars={T}]{total.dos}\total


Will compile properly, i.e. "T" is now considered to start a comment line.

-
Nice. Is there also a solution for disallowed words, or a solution that allows you to exclude certain line numbers? – Marc van Dongen Jan 22 '12 at 18:21
Particular line numbers are not so simple (as far as I know), although there are other questions knocking around on TeX.sx to do with reading particular lines. The comment chars is supposed to be a comma separated list, so I tried comment chars={THIS} but LaTeX didn't like it. May be limited to single characters. – qubyte Jan 22 '12 at 18:27
Thank you. I didn't know about comment chars. – Philipp Jan 22 '12 at 18:51
You could also prefix the lines you want ignored with a common comment character, such as #. This is pretty easy to do in an editor and leaves letters, such as T, free to show up in the data. – Sharpie Jan 22 '12 at 20:12
@Sharpie: If this was an option, then Philipp could simply delete those lines. I'm assuming that Philipp needs a semi-automatic way to handle these files, which can't be altered directly. – qubyte Jan 23 '12 at 1:39