[Tex/LaTex] TikZ node pin angle in 2D plot

pgfplotstikz-pgf

I would like to rotate the pin corresponding to the point -3.09% to the left, but when I increase the angle past 87, it snaps to 90 and the minus sign gets in the ticks and even at 87, it doesn't look like 87 degrees (probably snapped to a lower angle). Is there a way to remove the angle snap? Here is my figure:

\begin{tikzpicture}
\begin{axis}[clip=false,xmin=0,xmax=14,ymin=-70,ymax=20,major tick style={black},minor tick style={thin,black},minor x tick num=0,minor y tick num=4]
\draw[black](axis cs:0,0) -- (axis cs:14,0);
\addplot[color=blue,solid] coordinates {
(0,-61.5889524031168)
(1,-3.08914165008118)
(2,-6.51818367010861)
(3,2.54536181619180)
(4,-2.52797347614671)
(5,1.94530113590041)
(6,-1.68178736194508)
(7,1.45004681381708)
(8,-1.28443807064115)
(9,1.14729132172417)
(10,-1.04082348053453)
(11,0.948346997577710)
(12,-0.874976296246089)
(13,0.808047053786472)
(14,-0.754723886152266)
};
\addplot+[blue,mark=o,only marks]coordinates {
(0,-61.5889524031168)
(1,-3.08914165008118)
(2,-6.51818367010861)
(3,2.54536181619180)
(4,-2.52797347614671)
(5,1.94530113590041)
(6,-1.68178736194508)
(7,1.45004681381708)
(8,-1.28443807064115)
(9,1.14729132172417)
(10,-1.04082348053453)
(11,0.948346997577710)
(12,-0.874976296246089)
(13,0.808047053786472)
(14,-0.754723886152266)
}
node[pos=0,pin=10:${-}61.59$\%] {}
node[pos=0.1,pin=87:${-}3.09$\%] {}
node[pos=0.15,pin=290:${-}6.52$\%] {}
node[pos=0.2,pin=75:$2.55$\%] {}
node[pos=1,pin=210:${-}0.75$\%] {};
\end{axis}
\end{tikzpicture}

Best Answer

Here is a customization of the answer that I took from How can I force TikZ pin angle? .

Replacing the problematic code with the following

node[pos=0.1,pin={[inner sep=0pt,label={[inner ep=0pt,xshift=-5mm]80:${-}3.09$\%}]80:{}}] {}

gives

enter image description here

A bit of explanation of this code:

Labels are themselves are nodes so usual settings apply directly. However, skipping the cause of the problem and referring to the linked question, we need to put an empty label (which is a node) and then label that one again with Jake's neat idea. But keep in mind that you have to change the angle in both occasions (80 right now). Then because the pin points to the empty node we have to further shift its own label to the left by xshift=-5mm, you can adjust for your needs for that extra space you mentioned. The rest is hopefully relatively easy to understand.

Related Solutions

[Tex/LaTex] How to force TikZ pin angle

To disable the snapping of the pin node, you can redefine the following internal macro (taken from https://tex.stackexchange.com/a/85669/2552):

\makeatletter
\def\tikz@auto@anchor{%
    \pgfmathtruncatemacro\angle{atan2(\pgf@x,\pgf@y)-90}
    \edef\tikz@anchor{\angle}%
}
\makeatother

Full code:

\documentclass[border=5mm]{standalone}
\usepackage{tikz}

\makeatletter
\def\tikz@auto@anchor{%
    \pgfmathtruncatemacro\angle{atan2(\pgf@x,\pgf@y)-90}
    \edef\tikz@anchor{\angle}%
}
\makeatother

\begin{document}
    \begin{tikzpicture}
    \draw (0,0) -- (90:2.7) -- ++ (-13:12) 
        node[
            shape=rectangle,
            pos=0.6,
            sloped,
            above,
            draw,
            pin=270:$mg\cos(\theta)$
        ] 
        {5kg} -- ++(0:-11.6);
    \draw[dashed] (0,2.7) -- (13:11.6);
    \draw (2,2.7) arc (0:-13:2) ;
    \draw (3.2,2.4) node {$\sin \alpha$};
    \end{tikzpicture}
\end{document}

If you don't want to redefine the macro, you could construct a pin that honours the angle using a combination of an empty pin and a label

To do this, you need an empty pin label with an inner sep of 0. Then the pin line ends up exactly where you want it. Since only having a pin line without a pin label would be a bit pointless, we can fake the label using a label in the options of the empty pin. So pin={[inner sep=0pt, label={[inner sep=0pt]270:$mg\cos(\theta)$}]270:{}} works beautifully in this case. You could wrap this into a style so it's easier to handle.

Edit: It turns out (from TikZ node pin angle in 2D plot) that the label part also has a snapping behaviour that can be undesirable. To place the label text properly in line with the pin line, a "normal" node with the correct anchor instead of a label node has to be used. Here's a new style, precise pin=<angle>:<label text> that will place a pin with the proper angle and correctly placed label text:

precise pin/.style args={#1:#2}{
    pin={[
        inner sep=0pt,
        label={[
            append after command={
                node [
                    inner sep=0pt,
                    at=(\tikzlastnode.#1),
                    anchor=#1+180
                ] {#2}
            }
        ]center:{}}
    ]#1:{}}
}

\documentclass{standalone}
\usepackage{tikz}

\tikzset{
    precise pin/.style args={#1:#2}{
        pin={[
            inner sep=0pt,
            label={[
             append after command={
                    node [
                        inner sep=0pt,
                        at=(\tikzlastnode.#1),
                        anchor=#1+180
                    ] {#2}
                }
            ]center:{}}
        ]#1:{}}
    }
}
\begin{document}
    \begin{tikzpicture}
    \draw (0,0) -- (90:2.7) -- ++ (-13:12) 
        node[
            shape=rectangle,
            pos=0.6,
            sloped,
            above,
            draw,
            precise pin=270:$mg\cos(\theta)$
        ] 
        {5kg} -- ++(0:-11.6);
    \draw[dashed] (0,2.7) -- (13:11.6);
    \draw (2,2.7) arc (13:0:2) ;
    \draw (3.2,2.4) node {$\sin \alpha$};
    \end{tikzpicture}
\end{document}

[Tex/LaTex] pgfplots: percentage in matrix plot

It does not work in your MWE because you are overwriting it by also giving the option nodes near coors to the \addplot command. Remove the latter one (or specify format here), and it will print. I added a thinspace before the percentage sign, although it can also be recommended to load the siunitx package and let that format and typeset the values for you.

Anyway, here's the quickfixed version:

\documentclass[border=3pt]{standalone}
\usepackage{pgfplots}
\pgfplotsset{%
  width=5cm,
  height=18cm,
  compat=1.13,
  colormap={blackwhite}{gray(0cm)=(1); gray(1cm)=(0.5)},
  xticklabels={LPIBG, ALL, HPIBG},
  xtick={0,...,2},
  ytick=\empty
}

\begin{document}
\begin{tikzpicture}
\begin{axis}[%
  enlargelimits=false,
  xlabel style={font=\footnotesize},
  ylabel style={font=\footnotesize},
  legend style={font=\footnotesize},
  xticklabel style={font=\footnotesize},
  yticklabel style={font=\footnotesize},
  colorbar,
  colorbar style={%
    ytick={0,20,40,60,80,100},
    yticklabels={0,20,40,60,80,100},
    yticklabel={\pgfmathprintnumber\tick\,\%},
    yticklabel style={font=\footnotesize}
  },
  point meta min=0,
  point meta max=100,
  nodes near coords={\pgfmathprintnumber\pgfplotspointmeta\,\%},
  every node near coord/.append style={xshift=0pt,yshift=-7pt, black, font=\footnotesize},
]

\addplot[
matrix plot,
mesh/cols=3,
point meta=explicit]
table[meta=C]{
  x y C
  0 0 80
  1 0 36
  2 0 40
  0 1 64
  1 1 80
  2 1 60
  0 2 52
  1 2 84
  2 2 72
  0 3 72
  1 3 28
  2 3 32
  0 4 56
  1 4 84
  2 4 80
  0 5 72
  1 5 52
  2 5 44
  0 6 4
  1 6 84
  2 6 41
  0 7 37
  1 7 69
  2 7 84
  0 8 63
  1 8 53
  2 8 82
  0 9 78
  1 9 74
  2 9 39
  0 10 39
  1 10 63
  2 10 88
  0 11 76
  1 11 74
  2 11 49
  0 12 39
  1 12 6
  2 12 88
  0 13 46
  1 13 33
  2 13 75
  0 14 88
  1 14 67
  2 14 54
  0 15 79
  1 15 83
  2 15 75
  0 16 50
  1 16 46
  2 16 71
  0 17 92
  1 17 71
  2 17 75
  0 18 46
  1 18 33
  2 18 8
};
\end{axis}
\end{tikzpicture}
\end{document}

Best Answer

Related Solutions

[Tex/LaTex] How to force TikZ pin angle

[Tex/LaTex] pgfplots: percentage in matrix plot

Related Question