Posicionando o eixo pgfplots no tikzpicture

Question

Quero colocar um gráfico pgfplots ao lado de várias outras imagens PDF que importo para o meu documento, mas não consigo descobrir como posicionar os pgfplots axisno tamanho maior tikzpicture:

\documentclass{article}

\usepackage{graphicx}
\usepackage{pgfplots}
\pgfplotsset{compat=1.9}

\begin{document}
\begin{figure*}

  \begin{center}
    \begin{tikzpicture}

       \node[anchor=south west] (img) at (0,0) 
            {\includegraphics[width=0.3\linewidth]{1.pdf}};
       \node[anchor=south west] 
            at (0.01\linewidth,0.01\linewidth) {a};        

       \node[anchor=south west] (img) at (0.33\linewidth,0) 
            {\includegraphics[width=0.3\linewidth]{1.pdf}};
       \node[anchor=south west] 
            at (0.34\linewidth,0.01\linewidth) {b}; 

       \begin{axis}[width=0.45\linewidth, yticklabels={}]
         \addplot [const plot, fill=red] 
                  table [x index=0, y index=1]
                  {hist.txt}
         \closedcycle;  
       \end{axis}

    \end{tikzpicture}
  \end{center}

  \caption{\label{detdemo}An example of my output}
\end{figure*}
\end{document}

aqui está o exemplo de saída:

O axisparece começar a partir (0,0)do tikzpicture.

Queria ver como posso posicionar esse eixo depois da segunda foto? De modo que o canto inferior esquerdo esteja ativado (0.66\linewidth,0).

Answer 1

Você pode definir a coordenada para o canto inferior esquerdo do axiscom a attecla,

at={(0.66\linewidth,0)}

Adicione isso às axisopções.

\documentclass{article}

\usepackage{graphicx}
\usepackage{pgfplots}
\pgfplotsset{compat=1.9}

\begin{document}
\begin{figure*}

  \begin{center}
    \begin{tikzpicture}

       \node[anchor=south west] (img) at (0,0) 
            {\includegraphics[width=0.3\linewidth]{example-image-a}};
       \node[anchor=south west] 
            at (0.01\linewidth,0.01\linewidth) {a};        

       \node[anchor=south west] (img) at (0.33\linewidth,0) 
            {\includegraphics[width=0.3\linewidth]{example-image-b}};
       \node[anchor=south west] 
            at (0.34\linewidth,0.01\linewidth) {b}; 

       \begin{axis}[width=0.45\linewidth, yticklabels={},at={(0.66\linewidth,0)}]
         \addplot [const plot, fill=red] 
                  {x}
         \closedcycle;  
       \end{axis}

    \end{tikzpicture}
  \end{center}

  \caption{\label{detdemo}An example of my output}
\end{figure*}
\end{document}

Answer 2

Como um hack rápido, você pode usar um scopecom um xshiftarquivo .axisnode

\documentclass{article}

\usepackage{graphicx}
\usepackage{pgfplots}
\pgfplotsset{compat=1.9}
\usetikzlibrary{positioning}

\begin{document}
\begin{figure*}

  \begin{center}
    \begin{tikzpicture}

       \node[anchor=south west] (img1) at (0,0)
            {\includegraphics[width=0.3\linewidth]{example-image-a}};
       \node[anchor=south west]
            at (0.01\linewidth,0.01\linewidth) {a};

       \node[anchor=south west] (img2) at (0.33\linewidth,0)
            {\includegraphics[width=0.3\linewidth]{example-image-b}};
       \node[anchor=south west]
            at (0.34\linewidth,0.01\linewidth) {b};
       \begin{scope}[xshift=0.66\linewidth] 
       \begin{axis}[width=0.45\linewidth, yticklabels={}]
         \addplot [const plot, fill=red]
                  {x}       %% I changed this change it back
         \closedcycle;
       \end{axis}
       \end{scope}

    \end{tikzpicture}
  \end{center}

  \caption{\label{detdemo}An example of my output comes here}
\end{figure*}
\end{document}

Mas será melhor se você usar outro tikzpictureambiente IMO.