Dynamic feature of tikzpicture

Question

I am using beamer to create a presentation. Suppose we have two functions $f$ and $g$ to be plotted in one picture. I want to make the following effect. First, the function $f$ is displayed, and after, let's say, 0.5 or 1 second, the function $g$ is displayed in the same picture, and the function $f$ now disappeared, that is, only the function $g$ is remained.

\begin{figure}[!htb]
\centering
\begin{tikzpicture}
\begin{axis}[grid=both,xmin=0,xmax=1,
xtick={0,1},
ymin=0,ymax=1,
ytick={0,1},
width=7cm]
\addplot[color=black,mark=none] table {function_f.txt};
\addplot[color=black,mark=none] table {function_g.txt};
\end{axis} 
\end{tikzpicture}
\end{figure}

Suppose that the functions $f$ and $g$ are stored in the files function_f.txt and function_g.txt, respectively.

Is there anyone know how to do this? Thanks a lot.

Answer 1

If you're okay with "manually animating" the slides, i.e. making transitions by clicking on the mouse/keyboard/pointer, then you can set a TikZ style that allows Beamer overlay specifications as in this answer. The following example illustrates how you can overlay several \addplot commands. Notice the use of key visible on=<num> for the \addplot command.

Code (with Beamer overlay)

\documentclass{beamer}
\usepackage{pgfplots}
\tikzset{
  invisible/.style={opacity=0},
  visible on/.style={alt={#1{}{invisible}}},
  alt/.code args={<#1>#2#3}{%
    \alt<#1>{\pgfkeysalso{#2}}{\pgfkeysalso{#3}} % \pgfkeysalso doesn't change the path
  },
}

\begin{document}
\begin{frame}
\centering
\begin{tikzpicture}
  \begin{axis}[ymin=0,ymax=1,enlargelimits=false]
    \addplot
    [blue!80!black,fill=blue,fill opacity=0.5,visible on=<2>]
    coordinates
    {(0,0.1) (0.1,0.15) (0.2,0.5) (0.3,0.62)
      (0.4,0.56) (0.5,0.58) (0.6,0.65) (0.7,0.6)
    (0.8,0.58) (0.9,0.55) (1,0.52)}
    |- (axis cs:0,0) -- cycle;
    \addplot
    [red,fill=red!90!black,opacity=0.5,visible on=<3>]
    coordinates
    {(0,0.25) (0.1,0.27) (0.2,0.24) (0.3,0.24)
      (0.4,0.26) (0.5,0.3) (0.6,0.23) (0.7,0.2)
    (0.8,0.15) (0.9,0.1) (1,0.1)}
    |- (axis cs:0,0) -- cycle;
    \addplot[green!20!black,visible on=<4>] coordinates
    {(0,0.4) (0.2,0.75) (1,0.75)};
  \end{axis}
\end{tikzpicture}
\end{frame}
\end{document}

---

However, if it is real animation you're after, then the animate package is an option. The following example shows how this can be done.

Code (with animate)

\documentclass{beamer}
\usepackage{pgfplots}
\usepackage{animate}
\newcommand\myplot[1]{
  \ifnum#1=1 
  \else\ifnum#1=2
    \addplot
    [blue!80!black,fill=blue,fill opacity=0.5]
    coordinates
    {(0,0.1) (0.1,0.15) (0.2,0.5) (0.3,0.62)
      (0.4,0.56) (0.5,0.58) (0.6,0.65) (0.7,0.6)
    (0.8,0.58) (0.9,0.55) (1,0.52)}
    |- (axis cs:0,0) -- cycle;
  \else\ifnum#1=3
    \addplot
    [red,fill=red!90!black,opacity=0.5]
    coordinates
    {(0,0.25) (0.1,0.27) (0.2,0.24) (0.3,0.24)
      (0.4,0.26) (0.5,0.3) (0.6,0.23) (0.7,0.2)
    (0.8,0.15) (0.9,0.1) (1,0.1)}
    |- (axis cs:0,0) -- cycle;
  \else\ifnum#1=4
    \addplot[green!20!black] coordinates
    {(0,0.4) (0.2,0.75) (1,0.75)};
  \else error
  \fi\fi\fi\fi
}
\begin{document}
\begin{frame}
\centering
\begin{animateinline}[autoplay,loop]{1}
  \multiframe{4}{i=1+1}{
    \begin{tikzpicture}
      \begin{axis}[ymin=0,ymax=1,enlargelimits=false]
        \myplot{\i}
      \end{axis}
    \end{tikzpicture}  
  }
\end{animateinline}
\end{frame}
\end{document}

Output