# Aligning vectors of different height at bottom

I am trying to align several vectors of different height at the bottom. I am aware that this is not the typical convention, but I would like to have vector-entries with same index at same height to pronounce that some vectors start with a lower index than others. In each vector, the last index is the same, sucht that the vectors should be aligned to their bottom.

Consider the MWE:

\documentclass[10pt,a4paper]{article}
\usepackage{amsmath}
\begin{document}
\begin{align}
\tilde a = \begin{bmatrix} a_1\\ a_2 \\ \vdots \\ a_{10}\end{bmatrix},\quad
\tilde b = \begin{bmatrix} b_{-4} \\ \vdots  \\ \vdots  \\ b_1\\ b_2 \\ \vdots \\ b_{10}\end{bmatrix},\quad
\tilde c = \begin{bmatrix} b_{-3} \\ \vdots  \\ c_1\\ c_2 \\ \vdots \\ c_{10}\end{bmatrix}
\end{align}
\end{document}


I would like to get the following output:

Any idea if this i possible?

• Welcome to TeX.SE! Commented Dec 7, 2022 at 10:13

With the package nicematrix and \renewcommand{\arraystretch}{1.8} 1.8 found by trying. Is it sufficient for you?

    \documentclass[10pt,a4paper]{article}
\usepackage{amsmath}
\usepackage{nicematrix}
\begin{document}
\renewcommand{\arraystretch}{1.8}
$\tilde a =\begin{bNiceMatrix} a_1 \\ a_2 \\ \vdots \\ a_{10} \end{bNiceMatrix}$,\quad%
$\tilde b =\begin{bNiceMatrix}[baseline=line-6] b_{-4} \\ \vdots \\ \vdots \\ b_1\\ b_2 \\ \vdots \\ b_{10} \end{bNiceMatrix}$,\quad%
$\tilde c = \begin{bNiceMatrix}[baseline=line-5] b_{-3} \\ \vdots \\ c_1\\ c_2 \\ \vdots \\ c_{10}\end{bNiceMatrix}$
\end{document}


• Thanks, this works well in my case even without any \arraystretching. I appreciate the clean solution. Commented Dec 7, 2022 at 12:11
• @Jannik, Thanks, this solution may help out, but it's not accurate, Celdor's proposal will work in any case Commented Dec 7, 2022 at 12:19

The easiest way is to apply \raisebox{v-len}{$math content$}. v-len is a unit length the content is risen by; it can also be negative in order to lower boxes.

v-len can also be calculated but the first equation has to be to put in a saved box to measure its height. Then, the other equations can be risen by the difference between heights of two boxes.

\documentclass[10pt,a4paper]{article}
\usepackage{amsmath}
\newsavebox\firsteq
\newlength\eqth
\begin{document}
\sbox\firsteq{%
\ensuremath{
\begin{bmatrix}
a_1 \\
a_2 \\
\vdots \\
a_{10}
\end{bmatrix}}}
\setlength\eqth{\dimexpr\ht\firsteq+\dp\firsteq}

\begin{align}
\tilde b = \raisebox{\dimexpr0.5\totalheight-0.5\eqth}{$\begin{bmatrix} b_{-4} \\ \vdots \\ \vdots \\ b_1 \\ b_2 \\ \vdots \\ b_{10} \end{bmatrix}$},\quad
\tilde c = \raisebox{\dimexpr0.5\totalheight-0.5\eqth}{$\begin{bmatrix} b_{-3} \\ \vdots \\ c_1 \\ c_2 \\ \vdots \\ c_{10} \end{bmatrix}$}, \quad
\tilde c = \raisebox{\dimexpr0.5\totalheight-0.5\eqth}{$\begin{bmatrix} b_{-3} \\ c_1 \\ \end{bmatrix}$}