How do I change a separator in tabular just for one row in LaTeX? - latex

Question

I'd like to change a column separator just for one row in my tabular.
For now, the = is set up as a separator between columns, for the last row I would like to change it for a \vdots.
Thanks a lot.
EDIT:
I did what #achim suggested and it works, but still is there any ''nicer'' solution?

Answer 1

here is a proposition to use the align environment to align the equation you need and write all the math in one same environment rather than in a tabular.
It only require the package amsmath in the beginning of the file.
\documentclass[10pt,a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsmath}
\begin{document}
Proposal
\begin{align*}
\text{vychozi tvar} & ~ & y' + p(x) y &= q(x) \\ \hline
\text{reseni} & ~ & y' + p(x)y &= q(x) / \cdot e^{\int p(x)\, \dx} \\
& ~ & \left(y\cdot e^{\int p(x)\, \dx}\right) &=
q(x) \cdot e^{\int p(x)\, \dx} / \text{integrace} \\
& ~ & y\cdot e^{\int p(x)\, \dx} &= \int q(x) \cdot e^{\int p(x)\, \dx}\, \dx \\
& ~ & ~ &\vdots \\
\end{align}
\end{document}
The alignement is made with & sign and you can specify if it is = after or \vdots. You can still use text in this environment, juste use \text{lorem ipsum}.
This environment can number the line, juste remove * in \begin{align*}.
I tried to copy the bit of code you provided in picture, in future, include it in your question so we can solve issue quickly. Sorry if I made typos in my copy, I hope this suite your case.
EDIT : You may want to add the vertical line between the left text and your equations...here is a second solution, however I can't manage to align the equation all along
\begin{tabular}{l|l}
vychozi tvar & \parbox{0.3\linewidth}{%
\begin{align*}
y' + p(x) y &= q(x) \\
\end{align*}}\\ \hline
reseni & \parbox{0.3\linewidth}{%
\begin{align*}
y' + p(x)y = q(x) / \cdot e^{\int p(x)\, \dx} \\
\end{align*}} \\
~ & \parbox{0.3\linewidth}{
\begin{align*}
\left(y\cdot e^{\int p(x)\, \dx}\right) &=
q(x) \cdot e^{\int p(x)\, \dx} / \text{integrace} \\
y\cdot e^{\int p(x)\, \dx} &= \int q(x) \cdot e^{\int p(x)\, \dx}\, \dx \\
~ &\vdots & ~ \\
\end{align*}} \\
\end{tabular}