# Useful LaTeX packages: tables and figures

This is part of a short series of entries on LaTeX packages I found useful while preparing the examination copy of my PhD thesis.

Today’s entry is packages relevant to preparing tables or figures. Again, some are pretty widely known and some aren’t.

## rotating

If you have a big table or figure that should be rotated sideways onto its own page:

`usepackage{rotating}`

And then you can replace the table and figure commands with:

```begin{sidewaystable}
%Giant table goes here
end{sidewaystable}
begin{sidewaysfigure}
%Giant figure goes here
end{sidewaysfigure}```

## dcolumn

The dcolumn package produces tabular columns that are perfectly aligned on a decimal point (ie all the decimal points in that column are exactly underneath each other), which is usually how you want to display decimal numbers.

```usepackage{dcolumn}

% create a new column type, d, which takes the . out of numbers, replacing the .
% with a cdot and aligning on it.
newcolumntype{d}[1]{D{.}{cdot}{#1}}```

Now that you have defined the column type, you can use d in the tabular environment, where the numeric argument is the number of figures to expect after the decimal point. You don’t have to use exactly that number of figures in every entry, just that that’s how much room it will leave.

```% a tabular enviroment with a 1 and 3 figures after the decimal point column
begin{tabular}{d{1}d{3}}
1.6 & 1.657
\
2.0 & 6.563
\
7 & 6.26
\
end{tabular}```

One annoying aspect of this package is that for the headers of that column, which probably aren’t numbers, you will need to use multicolumn to get them to display nicely.

```% a tabular enviroment with a 1 and 3 figures after the decimal point column
begin{tabular}{d{1}d{3}}
1.6 & 1.657
\
2.0 & 6.563
\
7 & 6.26
\
end{tabular}```

You can mix the d column type with the usual l, r and p column types.

## threeparttable

You can’t use footnote in a floating table. This is one of several packages that allow table footnotes in various ways.

`usepackage{threeparttable}`

threeparttable doesn’t cause tables to float on its own, so you usually want to wrap in a table command:

```begin{table}

begin{threeparttable}

% Normal bits of your table go here, and use tnote{a} and
% tnote{b} and so to generate a note mark

begin{tablenotes}
tnote General note
tnote General note 2
tnote[a] Note for mark a
tnote[b] Note for mark b
end{tablenotes}

end{threeparttable}

caption{Caption goes here}
end{table}```

Unfortunately you need to generate the a, b, c (or whatever) numbering manually.

The general tnote entries are useful for things like “Bold entries are highest in the column”, so that they don’t need to go in the caption.