# [Tex/LaTex] Draw a line over a node Tikz

drawlinenodestikz-pgf

Can someone help me to draw a red line — like in the photo?
Thank you so much in advanced.

\begin{tikzpicture}
\node[draw,fill=white,ellipse,minimum height=4cm,minimum width=7cm,text width = 5cm,align=center,label=above:\textbf{qStqsfate-spqsface mqsdfodel}] (A)
{Tranqsdfqsiqsftion \\
$\tilde{y}_{t/t-1} = g \big( \tilde{y}_{t-1} ; u_t ; \omega_t \big)$ \\
$\downarrow$ \\
Measurement\\
$\tilde{z}_{t/t-1} = f \big( \tilde{y}_{t-1} ; u_t ; \omega_t \big)$  };
\node[xshift=8cm,draw,fill=white,ellipse,minimum height=4cm,minimum width=7cm,text width=5cm,align=center,label=above:\textbf{Estqsdfqsimateqsdfd daqsdfqsdta \; \; \; Empiriqsdfqsdfcal daqsdfqdsfta}] (B)
{$\; \; \tilde{y}_{t} \rightarrow \emptyset$ \\
\vspace{5mm}
$\tilde{z}_{t/t-1} \rightarrow z_t$};
\node[xshift=4cm,yshift=-4.5cm,draw,fill=white,ellipse,text width=4cm,align=center,label={[name=kalman]above:\textbf{Kqsdfqalmqsdfqan fqsdfqsdiltqsdfqser}}] (C)
{$v_t = y_t - y_{t,t-1}$};
\node[xshift=4cm,yshift=-6.5cm,draw,fill=white,rectangle,minimum height=1.2cm,text width=1.5cm,align=center] (D)
{$y_t$};

\draw [->] (A) to (kalman);
\draw [->] (B) to (kalman);
\draw [->] (C) to (D);

\end{tikzpicture}


Is this what you are looking for?

The node in question already has the name (B), therefore you simply want to draw a line from (B.south) to (B.north). To extend these coordinates slightly use yshift within the coordinates like so: ([yshift=-0.5cm]B.south) and ([yshift=0.5cm]B.north).

\documentclass[border=5mm]{standalone}
\usepackage{amsmath}
\usepackage{tikz}
\usetikzlibrary{shapes.geometric}
\begin{document}
\begin{tikzpicture}
\node[draw,fill=white,ellipse,minimum height=4cm,minimum width=7cm,text width = 5cm,align=center,label=above:\textbf{State-space model}] (A)
{Transition \\
$\tilde{y}_{t/t-1} = g \big( \tilde{y}_{t-1} ; u_t ; \omega_t \big)$ \\
$\downarrow$ \\
Measurement\\
$\tilde{z}_{t/t-1} = f \big( \tilde{y}_{t-1} ; u_t ; \omega_t \big)$  };
\node[xshift=8cm,draw,fill=white,ellipse,minimum height=4cm,minimum width=7cm,text width=5cm,align=center,label=above:\textbf{Estimated data \; \; \; Empirical data}] (B)
{$\; \; \tilde{y}_{t} \rightarrow \emptyset$ \\
\vspace{5mm}
$\tilde{z}_{t/t-1} \rightarrow z_t$};
\node[xshift=4cm,yshift=-4.5cm,draw,fill=white,ellipse,text width=4cm,align=center,label={[name=kalman]above:\textbf{Kalman filter}}] (C)
{$v_t = y_t - y_{t,t-1}$};
\node[xshift=4cm,yshift=-6.5cm,draw,fill=white,rectangle,minimum height=1.2cm,text width=1.5cm,align=center] (D)
{$y_t$};