你好，我画了一个条形图，并在每个条形上添加了标签。但是，正如你所见，我试图说明两个立面之间的相对差异，在某些情况下，即前两个条形和最后一个条形，相对差异恰好为负数，我该如何移动负号，使其不进入条形？
这是我的 MWE：
\documentclass[11pt,a4paper]{article}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\begin{document}
\begin{figure}[ht!]
\begin{center}
%0 - aramente 1 - Às vezes 2 - Quase sempre 4 - Sempre
\pgfplotstableread{
%2013-2014 %2012-2013
0 0 -5.2
1 0 -3.78
2 0 20.16
3 0 45.16
4 0 19.68
5 0 60.08
6 0 15.99
7 0 59.46
8 0 -2.46
}\dataset
\begin{tikzpicture}
\begin{axis}[ybar,
width=16cm,
height=8cm,
ymin=-10,
ymax=100,
ylabel={Relative difference (\%)},
xtick=data,
xticklabels = {
\strut GWP,
\strut ODP,
\strut POCP,
\strut AP,
\strut EP(T),
\strut EP(FW),
\strut EP(M),
\strut ADP,
\strut CED
%Category 5,
%Category 6
},
%xticklabel style={yshift=-10ex},
major x tick style = {opacity=0},
minor x tick style ={draw=none},
% minor tick length=2ex,
every node near coord/.append style={
anchor=west,
rotate=90
},
legend entries={conventional facade, BIPV facade},
legend columns=2,
legend style={draw=none,nodes={inner sep=3pt},at={(0.5,-0.2)},anchor=north},
]
\addplot[draw=black,fill=blue!20, nodes near coords] table[x index=0,y index=1] \dataset; %ano de 2013-2014
\addplot[draw=black,fill=blue!60, nodes near coords] table[x index=0,y index=2] \dataset; %ano de 2012-2013
\end{axis}
\end{tikzpicture}
\captionsetup{justification=centerlast, margin=10ex, labelfont=bf, format=plain, labelformat=default, labelsep=endash, font=small}
\caption{Impacts by category relative to baseline building with conventional facade.}\label{relative}
\end{center}
\end{figure}
\end{document}
答案1
负值进入条形图，因为默认情况下nodes near coords它们的将被绘制以下负条，但因为你声明anchor=west（在旋转节点上）它们现在全部画多于锚点。锚点仍然位于负条的负端。为了解决这个问题，您可以创建一个更改负条锚点的样式，如下所示。
（另请注意，我进一步“优化”了您的代码。）
% used PGFPlots v1.16
\documentclass[border=5pt]{standalone}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\pgfplotsset{compat=1.3}
\pgfplotstableread{
%2013-2014 %2012-2013
0 0 -5.2
1 0 -3.78
2 0 20.16
3 0 45.16
4 0 19.68
5 0 60.08
6 0 15.99
7 0 59.46
8 0 -2.46
}\dataset
\begin{document}
\begin{tikzpicture}
\begin{axis}[
ybar,
width=16cm,
height=8cm,
ymin=-10,
ymax=100,
ylabel={Relative difference (\%)},
xtick=data,
% (you don't need to place `\strut's here for each entry ...
xticklabels={
GWP,
ODP,
POCP,
AP,
EP(T),
EP(FW),
EP(M),
ADP,
CED
},
% ... just state this option)
typeset ticklabels with strut,
% (to also adjust the *placement* of the ticklabels when you don't
% want to show the major x ticks, first set the `major tick length'
% to zero ...
major tick length=0pt,
% ... and restore the old value for the yticks afterwards)
major y tick style={
/pgfplots/major tick length=1.5mm,
},
% -----------------------------------------------------------------
% adapted from <https://tex.stackexchange.com/a/141006/95441>
nodes near coords always on top/.style={
% a new feature since 1.9: allows to place markers absolutely:
scatter/position=absolute,
positive value/.style={
at={(axis cs:\pgfkeysvalueof{/data point/x},\pgfkeysvalueof{/data point/y})},
% draw, % <-- for debugging only, to check if placement is correct
},
negative value/.style={
at={(axis cs:\pgfkeysvalueof{/data point/x},0)},
% draw, % <-- for debugging only, to check if placement is correct
},
every node near coord/.append style={
check values/.code={%
\begingroup
% this group is merely to switch to FPU locally. Might be
% unnecessary, but who knows.
\pgfkeys{/pgf/fpu}%
\pgfmathparse{\pgfplotspointmeta<0}%
\global\let\result=\pgfmathresult
\endgroup
%
% simplifies debugging:
%\show\result
%
\pgfmathfloatcreate{1}{1.0}{0}%
\let\ONE=\pgfmathresult
\ifx\result\ONE
% AH : our condition 'y < #1' is met.
\pgfkeysalso{/pgfplots/negative value}%
\else
% ok, proceed as usual.
\pgfkeysalso{/pgfplots/positive value}%
\fi
},
check values,
anchor=west,
rotate=90,
},
},
nodes near coords={
\pgfmathprintnumber[fixed zerofill,precision=1]{\pgfplotspointmeta}
},
nodes near coords always on top,
% -----------------------------------------------------------------
legend entries={
conventional facade,
BIPV facade,
},
legend columns=-1,
legend style={
draw=none,
% (optimized the legend positioning, thus it is independent of the
% height/depth of the xticklabels. If you want to add a further
% yshift, use the optional second argument as in the commented
% version.)
at={(xticklabel cs:0.5)},
% at={(xticklabel cs:0.5,5pt)},
anchor=north,
},
]
\addplot [draw=black,fill=blue!20] table [x index=0,y index=1] \dataset;
\addplot [draw=black,fill=blue!60] table [x index=0,y index=2] \dataset;
\end{axis}
\end{tikzpicture}
\end{document}
答案2
您可以添加xshift=2ex到every node near coord/.append style：
\documentclass[11pt,a4paper]{article}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{pgfplotstable}
\begin{document}
\begin{figure}[ht!]
\begin{center}
%0 - aramente 1 - Às vezes 2 - Quase sempre 4 - Sempre
\pgfplotstableread{
%2013-2014 %2012-2013
0 0 -5.2
1 0 -3.78
2 0 20.16
3 0 45.16
4 0 19.68
5 0 60.08
6 0 15.99
7 0 59.46
8 0 -2.46
}\dataset
\begin{tikzpicture}
\begin{axis}[ybar,
width=16cm,
height=8cm,
ymin=-10,
ymax=100,
ylabel={Relative difference (\%)},
xtick=data,
xticklabels = {
\strut GWP,
\strut ODP,
\strut POCP,
\strut AP,
\strut EP(T),
\strut EP(FW),
\strut EP(M),
\strut ADP,
\strut CED
%Category 5,
%Category 6
},
%xticklabel style={yshift=-10ex},
major x tick style = {opacity=0},
minor x tick style ={draw=none},
% minor tick length=2ex,
every node near coord/.append style={
anchor=west,
rotate=90,
xshift=2ex
},
legend entries={conventional facade, BIPV facade},
legend columns=2,
legend style={draw=none,nodes={inner sep=3pt},at={(0.5,-0.2)},anchor=north},
]
\addplot[draw=black,fill=blue!20, nodes near coords] table[x index=0,y index=1] \dataset; %ano de 2013-2014
\addplot[draw=black,fill=blue!60, nodes near coords] table[x index=0,y index=2] \dataset; %ano de 2012-2013
\end{axis}
\end{tikzpicture}
\caption{Impacts by category relative to baseline building with conventional facade.}\label{relative}
\end{center}
\end{figure}
\end{document}