轴心处有阴影的区域

Question

根据建议，我将拆分我之前的（多个）问题分成不同的部分。

我想要阴影覆盖曲线下方的部分区域，但是使用填充的矩形会导致（当然）曲线顶部被阴影覆盖（不应该这样），而底部不被阴影覆盖（应该这样）。

我的代码是

\documentclass{article}
\usepackage{tikz,pgfplots}

\usepgfplotslibrary{fillbetween}

\pgfplotsset{compat = newest}


\begin{document}

\begin{figure}
   \begin{tikzpicture}
      \begin{axis}[
         ticks=none, 
         axis x line=bottom,
         axis y line=left,
         axis y discontinuity=crunch,
         xmin=0,xmax=1.3,
         ymin=0.5,ymax=1.3]
      \addplot[
         domain = 0:sqrt(1/3),
         samples =200,
         ] {sqrt(7/6-x^2)};
      \addplot[
         domain = sqrt(1/3):sqrt(7/6),
         fill = gray,
         fill opacity = 0.1,
         samples =200,
         y filter/.expression={x==sqrt(7/6 )?0:y},
         ] {sqrt(7/6-x^2)}\closedcycle;
      \addplot[
         domain = 0:7,
         samples =200,
         ] {sqrt(5/6)};
      \fill[gray, opacity = 0.1] (0,0) -- (0,0.9129) -- (0.5774,0.9129) -- (0.5774,0);
      \end{axis}
   \end{tikzpicture}
\end{figure}

\end{document}

Answer 1

\documentclass[tikz, border=1cm]{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}
\usepgfplotslibrary{fillbetween}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
ticks=none, 
axis x line=bottom,
axis y line=left,
axis y discontinuity=crunch,
xmin=0, xmax=1.3,
ymin=0.5, ymax=1.3,
y axis line style={name path=yaxis},
]
\addplot[
name path=circ,
domain=0:sqrt(7/6-1/4),
samples=200,
] {sqrt(7/6-x^2)};
\addplot[gray] fill between [of=yaxis and circ, reverse=false, soft clip={(-1,-1) rectangle (1,{sqrt(5/6)})}, on layer={axis background}];
\draw (0,{sqrt(5/6)}) -- (1.3,{sqrt(5/6)});
\draw ({sqrt(1/3)},0.5) -- ({sqrt(1/3)},{sqrt(5/6)});
\end{axis}
\end{tikzpicture}
\end{document}