I have two plots in a figure, for example
\documentclass{article}
\usepackage{pgfplots}
\usepgfplotslibrary{colormaps}
\pgfplotsset{compat=newest}
\begin{document}
\begin{tikzpicture}
\begin{axis}[colormap/hsv,point meta rel=per plot,colorbar]
\addplot[mesh,domain=1:10,samples=20,] {20*x+10}; %positive value
\addplot[mesh,domain=1:10,samples=20,] {-100};%negative value
\end{axis}
\end{tikzpicture}
\end{document}
The colorbar shows both the positive value and negative, but I want the colorbar only shows for the first plot. How can I do this?