如何才能避免低于 0 的超调？
这是我使用的代码：
\documentclass{article}
\usepackage{etex}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepgfplotslibrary{ternary}
\usepgfplotslibrary{groupplots}
\usetikzlibrary{pgfplots.groupplots}
\begin{document}
\begin{tikzpicture}
\pgfplotsset{every axis/.append style={solid},
every tick/.append style={semithick,color=black},
}
\begin{axis}[smooth,
scale only axis = true, width = 0.9\textwidth , height = 0.35\textwidth,
scaled ticks = false,
minor tick num =0,
thick,
ymin =-0.2, ymax =0.7, xmin =0, xmax=72,
legend style={font=\footnotesize,
legend pos =north west},
tickwidth = 0.15cm,
grid style ={dashed},
ylabel = {y},
xlabel={x},
grid = both
]
\addplot [no markers] coordinates{
(0,0.5)
(2,0.0)
(4,0.01)
(6,0.02)
(8,0.03)
(10,0.06)
(12,0.09)
(14,0.13)
(16,0.18)
(18,0.23)
(20,0.28)
(22,0.32)
(24,0.36)
(26,0.40)
(28,0.43)
(30,0.46)
(32,0.48)
(34,0.50)
(36,0.51)
(38,0.53)
(40,0.54)
} ;
\end{axis}
\end{tikzpicture}
\end{document}
答案1
您有以下几种选择：
- 不要使用
smooth，这会产生硬角（下面未显示）， - 设置
tension为较低的值，可以减少过冲，但会使拐角更难， - 如果允许的话，你可以加一分，或者
- 你可以结合最后两个选项（下面未显示）
（图例显示了 的值tension。）
\documentclass{article}
\usepackage{etex}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usepgfplotslibrary{ternary}
\usepgfplotslibrary{groupplots}
\usetikzlibrary{pgfplots.groupplots}
\begin{document}
\begin{tikzpicture}
\pgfplotsset{every axis/.append style={solid},
every tick/.append style={semithick,color=black},
}
\begin{axis}[smooth,
%
scale only axis = true, width = 0.9\textwidth , height = 0.35\textwidth,
scaled ticks = false,
minor tick num =0,
thick,
ymin =-0.2, ymax =0.7, xmin =0, xmax=72,
%
legend style={font=\footnotesize,
legend pos =north west},
%
tickwidth = 0.15cm,
grid style ={dashed},
%
ylabel = {y},
xlabel={x},
grid = both
]
\addplot+[no markers,tension=0.2] coordinates{
(0,0.5)
(2,0.0)
(4,0.01)
(6,0.02)
(8,0.03)
(10,0.06)
(12,0.09)
(14,0.13)
(16,0.18)
(18,0.23)
(20,0.28)
(22,0.32)
(24,0.36)
(26,0.40)
(28,0.43)
(30,0.46)
(32,0.48)
(34,0.50)
(36,0.51)
(38,0.53)
(40,0.54)
} ;
\addlegendentry{0.2}
% default value: tension=0.55
\addplot+[no markers] coordinates{
(0,0.5)
(2,0.0)
(4,0.01)
(6,0.02)
(8,0.03)
(10,0.06)
(12,0.09)
(14,0.13)
(16,0.18)
(18,0.23)
(20,0.28)
(22,0.32)
(24,0.36)
(26,0.40)
(28,0.43)
(30,0.46)
(32,0.48)
(34,0.50)
(36,0.51)
(38,0.53)
(40,0.54)
} ;
\addlegendentry{0.55 (default)}
\addplot+[no markers,tension=0.9] coordinates{
(0,0.5)
(2,0.0)
(4,0.01)
(6,0.02)
(8,0.03)
(10,0.06)
(12,0.09)
(14,0.13)
(16,0.18)
(18,0.23)
(20,0.28)
(22,0.32)
(24,0.36)
(26,0.40)
(28,0.43)
(30,0.46)
(32,0.48)
(34,0.50)
(36,0.51)
(38,0.53)
(40,0.54)
} ;
\addlegendentry{0.9}
\addplot+[no markers] coordinates{
(0,0.5)
(1,0.1) % added point
(2,0.0)
(4,0.01)
(6,0.02)
(8,0.03)
(10,0.06)
(12,0.09)
(14,0.13)
(16,0.18)
(18,0.23)
(20,0.28)
(22,0.32)
(24,0.36)
(26,0.40)
(28,0.43)
(30,0.46)
(32,0.48)
(34,0.50)
(36,0.51)
(38,0.53)
(40,0.54)
} ;
\addlegendentry{added point}
\end{axis}
\end{tikzpicture}
\end{document}