# pgfplots: Points with no marks but errorbars?

How can I plot data points with pgfplots that have no marks, but error bars? If I try marks=none and enable errobars, I get big filled circles with errobars. If I change my mark to mark=+, for example, I have to adjust the mark size by hand, so that the errorbars are bigger than the mark.

The reason is, if I have error bars, I automatically have the actual data point: the point where the error bars cross. So I don't need an explicit mark , but as described, just setting mark=none doesn't seem to be enough to achieve this.

This plots filled circles with error bars as marks even mark=none is set:

\begin{tikzpicture}
\begin{axis}
error bars/.cd, y dir=both, x dir=both, x explicit, y explicit]
table [x index=0, y index=2, x error index=1, y error index=3]
{mydata.txt};
\end{axis}
\end{tikzpicture}


Part of the content of mydata.txt to work with:

3.414   8E-3    3.62    5E-2
1.570   2E-2    1.65    1E-1
3.809   9E-3    3.96    3E-2
4.340   2E-2    4.34    3E-2


How do I get error bars without an actual mark symbol, so that the point is "auto-marked" by the crossing of the error bars?

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Could you include an MWE? –  Sean Allred Mar 29 at 12:24
Done. Hope this is enough. –  Foo Bar Mar 29 at 12:34
Sorry for replying late - internet is a little shoddy - but what exactly is in mydata.txt? (filecontents is a great environment if you're unaware ;)) –  Sean Allred Mar 29 at 13:08
I added a part of the data to work with. –  Foo Bar Mar 29 at 13:15
Yes, scatter plot seems to be the right term (English is not my native language). I want these (x+-dx, y+-dy) value pairs plotted (with errobars, but with marks and without "connecting lines"). –  Foo Bar Mar 29 at 13:29

Add the no markers option to the axis, and then supply scatter, only marks to the plot. Seems paradoxical, but it works:

\documentclass{article}
\usepackage{tikz,pgfplots,filecontents}
\begin{filecontents*}{mydata.txt}
3.414   8E-3    3.62    5E-2
1.570   2E-2    1.65    1E-1
3.809   9E-3    3.96    3E-2
4.340   2E-2    4.34    3E-2
\end{filecontents*}

\pgfplotsset{compat=1.7}

\begin{document}
\begin{tikzpicture}
\begin{axis}[no markers]
error bars/.cd,
y dir=both, x dir=both,
x explicit, y explicit]
table [x index=0, y index=2, x error index=1, y error index=3]
{mydata.txt};
\end{axis}
\end{tikzpicture}
\end{document}


Output:

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Thank you very much, this works. :) –  Foo Bar Mar 29 at 13:47
Thanks for the analysis. It should have worked to write only marks,mark=none. I will note this on the bug list for pgfplots to fix it eventually. –  Christian Feuersänger Mar 29 at 15:48
Thanks, Christian! Yeah, it's weird that it doesn't work like that, but it may have something to do with mark=none resetting all other options (it said something about this in the documentation). –  Sean Allred Mar 29 at 15:50