[Tex/LaTex] Quiver plot with pgfplots: scale arrowheads with arrowsize

arrowspgfplots

It is my understanding that the quiver plot with pgfplots keeps a constant arrowhead size, irrespective of the size (should I say length) of the arrow itself. Is there a way to have the arrowhead size linearly depending on the length of the arrow?

\documentclass[10pt,tikz]{standalone}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{pgfplots}
\usetikzlibrary{arrows.meta}
\begin{document}
\begin{tikzpicture}[scale=1]
\begin{axis}[domain=-3:3, view={0}{90}]
\addplot3[Couleur, quiver={u=-x, v={-y},scale arrows=0.085},-{Latex[width=2pt,length=3pt]},samples=21] {0};
\end{axis}
\end{tikzpicture}
\end{document}

EDIT: A possible solution is given below but it is not really convincing because the arrowhead size is hard to control. Furthermore, the line thickness is almost zero in the center of the figure while arrowheads do not vanish.

\documentclass[10pt,tikz]{standalone}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{pgfplots}
\begin{document}
\begin{tikzpicture}[scale=1]
\def\U{-x}\def\V{-y}\def\LEN{(sqrt((\U)^2 + (\V)^2)}
\begin{axis}[axis equal,view={0}{90}]
\addplot3[blue,point meta={\LEN},quiver={u={(\U)},v={(\V)},scale arrows=.15,every arrow/.append style={line width=\pgfplotspointmetatransformed/1000 * .5pt}},- latex,samples=24] {0};
\end{axis}
\end{tikzpicture}
\end{document}

enter image description here

Best Answer

The approach suggested by @Jake is the right direction. Unfortunately, -{Latex[width=...]} causes strange problems when used insided of every arrow. It appears that this kind of arrow key reconfiguration is unsupported. I will look into it eventually, sounds like some incompatibility between the arrows.meta library and pgfplots.

But it works if you use scale length which appears to be better suited anyway:

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.10}
\usetikzlibrary{arrows.meta}
\begin{document}
\begin{tikzpicture}
\begin{axis}[domain=-3:3, view={0}{90}]
\addplot3[blue,
    point meta={sqrt(x^2+y^2)},
    quiver={
        u=-x, 
        v={-y},
        scale arrows=0.085,
        every arrow/.append style={%
            -{Latex[scale length={max(0.1,\pgfplotspointmetatransformed/1000)}]},
        },
    },
    samples=21,
] 
    {0};
\end{axis}
\end{tikzpicture}


\end{document}

enter image description here

The idea as such is similar to that of How can I draw a quiver plot with varying line thickness? : we define point meta to resemble the vector length. Then we scale every arrow by \pgfplotspointmetatransformed/1000. Keep in mind that \pgfplotspointmetatransformed is a number in the range [0,1000]; it is the result of mapping the value of point meta into that range. Since scale length=0 is illegal, we have to introduce a lower limit here.

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