曲线更平滑

Question

使用所附代码，我得到了图片中的结果。在该范围内0-20，曲线明显有急剧变化，这在美学上并不好。

有没有办法让曲线更平滑？谢谢

\begin{tikzpicture}
\begin{axis}[
    width=\textwidth, height=10cm,
    xlabel=$Pressure~(m~water)$,
    ylabel={$Water~content~(v/v)$},
    legend style={draw=none, legend columns=2, at={(.9,.9)}}]
    \addplot+[blue,no marks,domain=0.001:160] {.508-1.52398*exp(-(13702.2/x)^0.13266)};
    \addplot+[violet,no marks,domain=0.001:160] {.445-0.34900*exp(-(30.0706/x)^0.23650)};
    \addplot+[red,no marks,domain=0.001:160] {.503-0.41288*exp(-(1.56530/x)^0.66572)};
    \addplot+[orange,no marks,domain=0.001:160] {.465-0.39848*exp(-(0.67406/x)^0.84737)};
    \addplot+[green,no marks,domain=0.001:160] {.350-0.31765*exp(-(0.53648/x)^1.21892)};
    \addplot+[brown,no marks,domain=0.001:160] {.395-0.38594*exp(-(0.07439/x)^0.92067)};
    \legend{Silty clay, Clay loam, Loam, Sandy loam, Medium fine loam, Coarsesand};
\end{axis}
\end{tikzpicture}

Answer 1

虽然该选项smooth使曲线更平滑，但也会导致边缘偏离，从而使图形不准确。最好使用sampleskey 并增加样本数量。样本越多，曲线越细。这里唯一的限制因素是编译时间和内存。下面是一个示例samples=500。

\documentclass{article}
\usepackage{pgfplots}
\begin{document}
  \begin{tikzpicture}
    \begin{axis}[
        width=\textwidth, height=10cm,
        xlabel=$Pressure~(m~water)$,
        ylabel={$Water~content~(v/v)$},
        legend style={draw=none, legend columns=2, at={(.9,.9)}}]
        \addplot+[blue,no marks,domain=0.001:160,samples=500] {.508-1.52398*exp(-(13702.2/x)^0.13266)};
        \addplot+[violet,no marks,domain=0.001:160,samples=500] {.445-0.34900*exp(-(30.0706/x)^0.23650)};
        \addplot+[red,no marks,domain=0.001:160,samples=500] {.503-0.41288*exp(-(1.56530/x)^0.66572)};
        \addplot+[orange,no marks,domain=0.001:160,samples=500] {.465-0.39848*exp(-(0.67406/x)^0.84737)};
        \addplot+[green,no marks,domain=0.001:160,samples=500] {.350-0.31765*exp(-(0.53648/x)^1.21892)};
        \addplot+[brown,no marks,domain=0.001:160,samples=500] {.395-0.38594*exp(-(0.07439/x)^0.92067)};
        \legend{Silty clay, Clay loam, Loam, Sandy loam, Medium fine loam, Coarsesand};
    \end{axis}
\end{tikzpicture}
\end{document}