# Align bar graph with error bars in groups on Y-axis

Am trying to align this in group of 3's but a bar in the AAAAAAAA group keeps going off alignment.

Note: I have checked "grouped bar chart with pgfplots" , "Bar graph with groups(inner group bars next to each other) and whitespace between groups including error bars [duplicate]" and "How can i create bar plot groups of different sizes in pgfplots?" and they don't answer my question - our data input format is different.

MWE:

\definecolor{bblue}{HTML}{82B1FF}
\definecolor{rred}{HTML}{FF8A80}

\begin{filecontents}{testdata.csv}
ALB,VAL,ERR,COR
AA,20.61,0.32,bblue
AA,20.88,0.55,bblue
AA,20.41,0.29,bblue
AAA,26.22,0.94,bblue
AAA,26.43,0.45,bblue
AAA,26.86,0.61,bblue
AAAA,29.91,0.76,bblue
AAAA,30.39,0.11,bblue
AAAA,30.11,0.49,bblue
AAAAA,34.71,0.43,rred
AAAAA,34.87,0.99,rred
AAAAA,34.81,0.26,rred
AAAAAA,40.33,0.64,rred
AAAAAA,40.18,0.03,rred
AAAAAA,40.4,0.83,rred
AAAAAAA,45.77,0.47,rred
AAAAAAA,45.93,0.95,rred
AAAAAAA,45.35,0.3,rred
AAAAAAAA,50.35,0.13,rred
AAAAAAAA,50.34,0.85,rred
AAAAAAAA,50.66,0.55,rred
\end{filecontents}
\makeatletter
\pgfplotsset{
/pgfplots/flexible yticklabels from table/.code n args={3}{%
\pgfplotstablegetcolumn{#2}\of{\coordinate@table}\to\pgfplots@yticklabels
\let\pgfplots@yticklabel=\pgfplots@user@ticklabel@list@y
}
}
\makeatother
\begin{figure}

\begin{tikzpicture}
\begin{axis}[
ylabel=A labels,  y label style={at={(-0.1,0.5)}},
y = -0.3cm,
ybar, %=2*\pgflinewidth,
draw opacity=0.5,
bar width=6pt,
enlarge y limits={abs=7pt},
xbar,
width=.36\textwidth,
xlabel= unit,
%flexible xticklabels from table={testdata.csv}{ALB}{col sep=comma},
flexible yticklabels from table={testdata.csv}{ALB}{col sep=comma},
yticklabel style={font=\small,xshift=0.5ex,  anchor=east},
%xtick=data
ytick=data,
xmajorgrids
]
%\pgfplotsinvokeforeach {0}{
%style={color=cyan,fill=bblue,mark=none};
plot [error bars/.cd, x dir=both,x explicit ]
table[y expr={(\coordindex) - mod(\coordindex,3)/8},x=VAL, x error=ERR ] {\datatable};

\end{axis}

\end{tikzpicture}
\end{figure}

• This definitely looks like a bug in pgf to me, mod(18,3) gives 3, which is not expected. – TonioElGringo Oct 9 '17 at 8:07
• @TonioElGringo Does it? I get 0.0 from \documentclass[border=10pt]{standalone} \usepackage{pgf} \begin{document} \pgfmathparse{mod(18,3)}\pgfmathresult \end{document} – Torbjørn T. Oct 19 '17 at 7:43
• @TorbjørnT. Indeed it works with pgfmathparse, but something is broken in pgfplots, since \plot {mod(18,3)}; in an axis environment gives incorrect results. – TonioElGringo Oct 20 '17 at 13:53
• @TonioElGringo True. I posted a report at sourceforge.net/p/pgfplots/bugs/187 – Torbjørn T. Oct 20 '17 at 17:16

(Update 21.10.17.) This problem was caused by a bug in the floating point library: https://sourceforge.net/p/pgfplots/bugs/187/ It has been fixed by Christian Feuersänger, and when the next version of pgf or pgfplots is released the code should work properly without the workaround described below.

It could be that the 18 is seen as 17.99999 or something, so the mod gives the wrong output.

If you change to mod(\coordindex+0.001,3) the output is as expected.

• you have both ybar and xbar in the axis options, the ybar can be removed.
• \addplot plot[.. is mixing TikZ syntax (\draw plot) with pgfplots syntax, you want \addplot +[.. I think.
• As shown, you don't really need the flexible yticklabels stuff, yticklabels from table={\datatable}{ALB} is good enough.

\documentclass{article}
\usepackage{pgfplotstable,filecontents}

\begin{document}

\definecolor{bblue}{HTML}{82B1FF}
\definecolor{rred}{HTML}{FF8A80}

\begin{filecontents}{testdata.csv}
ALB,VAL,ERR,COR
AA,20.61,0.32,bblue
AA,20.88,0.55,bblue
AA,20.41,0.29,bblue
AAA,26.22,0.94,bblue
AAA,26.43,0.45,bblue
AAA,26.86,0.61,bblue
AAAA,29.91,0.76,bblue
AAAA,30.39,0.11,bblue
AAAA,30.11,0.49,bblue
AAAAA,34.71,0.43,rred
AAAAA,34.87,0.99,rred
AAAAA,34.81,0.26,rred
AAAAAA,40.33,0.64,rred
AAAAAA,40.18,0.03,rred
AAAAAA,40.4,0.83,rred
AAAAAAA,45.77,0.47,rred
AAAAAAA,45.93,0.95,rred
AAAAAAA,45.35,0.3,rred
AAAAAAAA,50.35,0.13,rred
AAAAAAAA,50.34,0.85,rred
AAAAAAAA,50.66,0.55,rred
\end{filecontents}

\begin{figure}

\begin{tikzpicture}
\begin{axis}[
ylabel=A labels,
y label style={at={(-0.1,0.5)}},
y = -0.3cm,
xbar, %=2*\pgflinewidth,
draw opacity=0.5,
bar width=6pt,
enlarge y limits={abs=7pt},
width=.36\textwidth,
xlabel= unit,
yticklabels from table={\datatable}{ALB},
yticklabel style={font=\small,xshift=0.5ex,  anchor=east},
ytick=data,
xmajorgrids
]
%\pgfplotsinvokeforeach {0}{