使用矩阵创建流程图

Question

我（只是）猜测你喜欢画下面的图：

抱歉，但我看不懂你的代码，所以接下来的 MWE 大部分都是我从头开始写的。这时我可能会误解你代码的某些部分。如果发生这种情况，请告诉我。

\documentclass[margin=3mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows.meta,
                backgrounds,
                fit,
                matrix,
                positioning}
\usepackage{xcolor}

\tikzset{
   arr/.style = {-{Triangle[scale=0.8]}, 
                 draw=gray, ultra thick,
                 shorten >=1mm, shorten <=1mm}, 
    en/.style = {draw=none, fill=none, text=black},
every label/.append style = {font=\bfseries, text=black, inner sep=0pt},
   FIT/.style = {draw=gray, fill=gray!30, rounded corners, 
                 inner xsep=2em, inner ysep=3ex, yshift=2ex,
                 fit = #1, node contents={}},
neuron/.style = {matrix of nodes,
                 nodes={draw=blue, rounded corners, fill=gray!50, 
                        text height=2ex, minimum width=6em, 
                        inner sep=1mm,
                        text=#1},
                 row sep=2mm,
                 outer sep=2mm},
        }
\begin{document}
    \begin{tikzpicture}[
node distance = 11mm
                        ]
%%%
\matrix (N0) [neuron=white]
{
|[label=:Avara Ka Davara]| Synapse$_1$         \\
Synapse$_2$         \\
|[en]| $\vdots$     \\
Synapse$_n$         \\
};
\scoped[on background layer]
    \node (f0) [FIT=(N0-1-1) (N0-4-1)];

\matrix (N1) [neuron=black, right=of N0]
{
|[label=Expecto Patronum]| Synapse$_1$ \\
Synapse$_2$     \\
Synapse$_3$     \\
Synapse$_4$     \\
};
\scoped[on background layer]
    \node (f1) [FIT=(N1-1-1) (N1-4-1)];

\matrix (N2) [neuron=black, right=of N1]
{
|[label=Expecto Patronum]| Synapse$_1$ \\
Synapse$_2$     \\
Synapse$_3$     \\
Synapse$_4$     \\
};
\scoped[on background layer]
    \node (f2) [FIT=(N2-1-1) (N2-4-1)];
%%%%
\draw[arr] (N0-1-1 -| f0.east) -- (N1-1-1 -| f1.west);
\draw[arr] (f1) -- (f2);
\coordinate[below left= of N0.south west] (aux);
\draw[arr] (f2.east) -- ++ (5mm,0) |- (aux) |- (f0);
    \end{tikzpicture}
\end{document}

附录： 您在评论中的请求可以通过不同的方式实现，但是如果您期望，该解决方案应该自动保持FIT节点的相等高度，那么这将成为一个非常苛刻/复杂的问题。

让我们首先展示一个更简单的情况，当FIT节点可以有不同的高度时：

\documentclass[margin=3mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{arrows.meta,
                backgrounds,
                fit,
                matrix,
                positioning}
\usepackage{xcolor}

\tikzset{
   arr/.style = {-{Triangle[scale=0.8]}, 
                 draw=gray, ultra thick,
                 shorten >=1mm, shorten <=1mm}, 
    en/.style = {draw=none, fill=none, text=black},
every label/.append style = {name=LN, anchor=south,     % <---
                 font=\bfseries, text=black, 
                 text width=10em, align=flush center,   % <---
                 yshift=1ex},                           % <---
   FIT/.style = {draw=gray, fill=gray!30, rounded corners, 
                 inner sep=1ex,
                 fit=#1, node contents={}},
neuron/.style = {matrix of nodes,
                 nodes={draw=blue, rounded corners, fill=gray!50, 
                        text height=2ex, minimum width=6em, 
                        inner sep=1mm,
                        text=#1},
                 row sep=2mm,
                 outer sep=0mm},
        }
\begin{document}
    \begin{tikzpicture}[
node distance = 0mm and 11mm                            % <---
                        ]
%%%
\matrix (N0) [neuron=white]
{
|[label=Avara Ka Davara
        Avara Ka Davara]| Synapse$_1$         \\        % <--- longer label
Synapse$_2$         \\
|[en]| $\vdots$     \\
Synapse$_n$         \\
};
\scoped[on background layer]
    \node (f0) [FIT=(LN) (N0-4-1)];                     % <---

\matrix (N1) [neuron=black, 
              above right=of N0.south east]             % <---
{
|[label=Expecto Patronum]| Synapse$_1$ \\
Synapse$_2$     \\
Synapse$_3$     \\
Synapse$_4$     \\
};
\scoped[on background layer]
    \node (f1) [FIT=(LN) (N1-4-1)];

\matrix (N2) [neuron=black,
              above right=of N1.south east]             % <---
{
|[label=Expecto Patronumy]| Synapse$_1$ \\
Synapse$_2$     \\
Synapse$_3$     \\
Synapse$_4$     \\
};
\scoped[on background layer]
    \node (f2) [FIT=(LN) (N2-4-1)];
%%%%
\draw[arr] (N0-1-1 -| f0.east) -- (N0-1-1 -| f1.west);  % <---
\draw[arr] (f1) -- (f1 -| f2.west);                     % <---
\coordinate[below left= 0.5 and 0.5 of N0.south west] (aux);    % <---
\draw[arr] (f2.east) -- ++ (0.5,0) |- (aux) |- (f0);
    \end{tikzpicture}
\end{document}

对于具有相等节点高度的解决方案，FIT请提出新问题，因为（i）这是新问题，而不是问题中提出的问题，（ii）这里已经睡觉时间有一段时间了......

Answer 1