Help me to draw a diagram in tikz

Question

Please help me to draw this diagram in LaTeX

Thanks in advance for your help.

Answer 1

An alternative to your solution:

Main differences in comparison to your solution:

• as document class is used standalone with option tikz. With it you can see only images. When you are satisfied with result, you can copy code to final document or include it with \input{<path>/<picture file name>}
• style difinition is part of tikzpicture options (use of tikzstyle is now depreciated, instead it is preferable \tikzset{...}, where styles had to be defined on the same way as in tikzpicture options)
• for node style I rather use mynode instead of yours node. Use node for style name is not good since it is already defined in TikZ for node ...
• for shape of main nodes i select signal. Using it I avoid all your scaling of regular polygon and have better control on shape size
• in positioning of nodes I rather use relative coordinates to coordinate of the main nodes. in this I exploit positioning library. Their distances are controlled by node distance = <vertical> and <horizontal>
• for drawing arrows I define auxiliary coordinates
• arrows are grouped by scope regarding their common features (dash pattern, direction)
• not at the end, I write code in my editor and for shape data look into TikZ & PGF manual, chapter 67 Shape Library, page 693 (shapes signal are described in section 67.4 Symbol Shapes, see page 713).

Complete MWE:

\documentclass[tikz, margin=3mm]{standalone}
    \usetikzlibrary{positioning, shapes.symbols}

\begin{document}
   \begin{tikzpicture}[ 
   node distance = 4mm and 16mm,
mynode/.style = {shape=signal, signal to=west and east,
                 draw, color = #1,
                 text width=1.3cm, align=flush center, 
                 inner xsep=0mm, inner ysep=2mm, font=\small}
                 ]
% main nodes
\node (A) [mynode=magenta]            {Text 2};
\node (B) [mynode=blue, below=of A]   {Text 3};
\node (C) [mynode=teal, below=of B]   {Text 4};
% coordinates for lines
\coordinate[left=of B.west]     (in2);
\coordinate[left=of in2]        (in1);
\coordinate[right=of B.east]    (out1);
\coordinate[right=of out1]      (out2);
% dashed arrows
    \begin{scope}[latex-, dashed, shorten >=1mm]
\draw[magenta] (A.west) -- + (-0.8,0) -- (in2);
\draw[blue]     (B.west) -- (in2);
\draw[magenta] (C.west) -- + (-0.8,0) -- (in2);
    \end{scope}
    \begin{scope}[-latex, dashed, shorten >=1mm]
\draw[magenta] (A.east) -- + (0.8,0) -- (out1);
\draw[blue]     (B.east) -- (out1);
\draw[magenta] (C.east) -- + (0.8,0) -- (out1);
    \end{scope}
% arrows with text
\draw[-latex] (in1) -- node[above] {Text 1} (in2);
\draw[-latex] (out1) -- node[above] {Text 5} (out2);
%--------------
   \end{tikzpicture}
\end{document}

Answer 2

I drew with help of tikzEdit editor (http://www.tikzedt.org/). This is the code that produces the figure

    \documentclass{article}

    \usepackage{tikz}
    \usetikzlibrary{positioning,shapes.geometric,shapes.misc}

   \begin{document}

   \begin{tikzpicture}
   %--------------
   \tikzstyle{node} = [ regular polygon, regular polygon sides=6,xscale=2,draw, 
                        scale=0.5,text centered,text width=1.3cm,inner sep=0pt]
   %--------------
   \node (v1) at (-4.5,3.5) {}; 
   \node (v2) at (-3,3.5) {}; 
   \draw [-latex] (v1) -- node[above] {\small Text 1} (v2);
   %--------------
   \draw [magenta,dashed] (v2) -- (-2.5,5) node (v3) {}; 
   \draw [-latex,magenta,dashed] (v3) -- (-1.5,5);
   \node [node,magenta] (A) at (-0.5,5)    {\small Text 2}; 
   %--------------
   \draw [-latex,blue,dashed] (v2) -- (-1.5,3.5);
   \node [node,blue]   (B) at (-0.5,3.5) {\small Text 3};
   %--------------
   \draw [teal,dashed] (v2) -- (-2.5,2) node (v5) {};
   \draw [-latex,teal,dashed] (v5) -- (-1.5,2);
   \node [node,teal]         (C) at (-0.5,2)    {\small Text 4};
   %--------------
   \node (v6) at (2,3.5) {}; 
   \node (v7) at (3.5,3.5) {}; 
   %--------------
   \draw [magenta,dashed] (0.6,5) -- (1.5,5) node (v8) {};
   \draw [-latex,magenta,dashed] (v8) -- (v6);
   \draw [-latex,blue,dashed](0.6,3.5) -- (v6);
   \draw [teal,dashed] (0.6,2) -- (1.5,2) node (v9) {}; 
   \draw [-latex,teal,dashed](v9) -- (v6);
   %--------------
   \draw [-latex] (v6) -- node[above] {\small Text 5} (v7);
   %--------------
   \end{tikzpicture}

  \end{document}