Continue long table beside on the same page

Question

I have a datatable in a CSV file and print it with pgfplotstable. I can split long datatables by making pgfplotstable use longtable instead of tabular environment; so far so good. My problem is that my datatable has only two columns, hence it results in pages like:

+-------------------------+
|          XX XX          |
|          XX XX          |
|          XX XX          |
|          XX XX          |
|          XX XX          |
|                         |
|                         |
+-------------------------+

The point is: left and right of the table there is much free space. I would like the table being printed as:

+-------------------------+
|  XX XX | XX XX | XX XX  |
|  XX XX | XX XX | XX XX  |
|  XX XX | XX XX | XX XX  |
|  XX XX | XX XX | XX XX  |
|  XX XX | XX XX | XX XX  |
|  XX XX | XX XX | XX XX  |
|  XX XX | XX XX | XX XX  |
|                         |
|                         |
+-------------------------+

I know that I can achieve this by using solutions like multicolumn long table or enumeration, but this has to disadvantages:

• I have to manually specify the number of columns to use
• the columns are not balanced
• I cannot use this inside a float like table

So, my question is: Is there a package that provides this feature, holding the above three points?

Answer 1

You can use /pgfplots/table/select equal part entry of={<part no>}{<part count>}, refer pgfplotstable manual, page 40. This code is taken from the manual with some modifications.

\documentclass{article}
\usepackage{pgfplotstable}
\usepackage{booktabs}
\usepackage{filecontents}
\begin{filecontents*}{pgfplotstable.example2.dat}
A B
A1 B1
A2 B2
A3 B3
A4 B4
A5 B5
A6 B6
A7 B7
A8 B8
A9 B9
A10 B10
A11 B11
A12 B12
A13 B13
A14 B14
A15 B15
A16 B16
A17 B17
A18 B18
A19 B19
A20 B20
A21 B21
\end{filecontents*}
\begin{document}
\pgfplotstableset{
every head row/.style={before row=\toprule,after row=\midrule},
every last row/.style={after row=\bottomrule}}
\pgfplotstabletypeset[string type]{pgfplotstable.example2.dat}%
%
\pgfplotstabletypeset[
columns={A,B,A,B},
display columns/0/.style={select equal part entry of={0}{2},string type},% first part of ‘A’
display columns/1/.style={select equal part entry of={0}{2},string type},% first part of ‘B’
display columns/2/.style={select equal part entry of={1}{2},string type},% second part of ‘A’
display columns/3/.style={select equal part entry of={1}{2},string type},% second part of ‘B’
]{pgfplotstable.example2.dat}

\end{document}

You can change the number of columns (parts) easily by changing part no and part count. For example to have three parts we do:

\pgfplotstabletypeset[
columns={A,B,A,B,A,B},
display columns/0/.style={select equal part entry of={0}{3},string type},% first part of ‘A’
display columns/1/.style={select equal part entry of={0}{3},string type},% first part of ‘B’
display columns/2/.style={select equal part entry of={1}{3},string type},% second part of ‘A’
display columns/3/.style={select equal part entry of={1}{3},string type},% second part of ‘B’
display columns/4/.style={select equal part entry of={2}{3},string type},% third part of ‘A’
display columns/5/.style={select equal part entry of={2}{3},string type},% third part of ‘B’
]{pgfplotstable.example2.dat}