Methods to edit column order in an existing LaTeX table?

Question

What is the best way of editing an existing LaTeX table? I need to swap the order of two columns and can't think of an efficient way of doing this.

My table is a long creature of the following structure:

A &     -0.523 &      26.94 &     0.8243 &     0.0000 &     -12.67 \\
B &     -0.614 &      30.02 &     0.8509 &     0.0000 &     -13.12 \\
C &     -0.630 &      32.92 &     0.9254 &     0.0000 &     -21.45 \

I need to change the values so that it is:

A &     26.94 &      -0.523 &     0.8243 &     0.0000 &     -12.67 \\
(etc)

The thoughts that I had were to import it into Excel and to drag columns around, and then use the concatenate() function to produce the number & number structure. I feel like there might be a better way of doing this that I am unaware of.

Answer 1

Any editor with regular expression replace can easily swap columns. For example on the command line if tab.tex contains your input this regexp will swap column 2 and 3. (You may need more or less backslashes in the regexp depending on the command line shell in use)

 sed -e "s/^\([^\&]*\)\&\([^\&]*\)\&\([^\&]*\)/\1\3\2/" tab.tex 
A       26.94      -0.523 &     0.8243 &     0.0000 &     -12.67 \\
B       30.02      -0.614 &     0.8509 &     0.0000 &     -13.12 \\
C       32.92      -0.630 &     0.9254 &     0.0000 &     -21.45 \

Answer 2

As a tip for the future:

When creating big tables, I make a command to encode the row.

\newcommand{\resultrow}[4]{#1 & #2 & #3 & #4 \\}

If you then want to change the order/layout of something you only have to change the command definition.

You should take care in making the command as descriptive as possible, and that the arguments are in the order that they are logical to the command not to the table. This will make later changes to the order simpler.

As per request, an example. Take this table:

\begin{tabular}{l l l l}
  a & b & c & d \\
  2.33 & 4.55 & 5.66 & 7.88 \\
  3.44 & 5.66 & 6.77 & 9.00 \\
  .......
\end{tabular}

If you then want to change the order of the columns, well see the other answers to this question. I would however solve it like this:

\newcommand{\abcdresults}[4]{ #1 & #2 & #3 & #4 \\}
\begin{tabular}{l l l l}
  a & b & c & d \\
  \abcresults{2.33}{4.55}{5.66}{7.88}
  \abcresults{3.44}{5.66}{6.77}{9.00}
  .......
\end{tabular}

If you then want to change the order, you can just simply change the body of \abcdresults to for instance: {\textbf{#3} & #1 & #2 & #4 \\}

Answer 3

+1 David for sed one-liner but with all due respect there is no better tool for working with tables than AWK. This is the solution for the above problem!

awk  'BEGIN {FS="&";OFS="&"}{print $1,$3,$2,$4,$5}' file.csv > newfile.csv

Answer 4

There are already good answers here, but there's a moral imperative to point out that, of course, there's an easy way to do this in emacs (or xemacs), without using regular expressions. You can copy a column to a register using copy-rectangle-to-register, paste it in as a new column using insert-register, and then delete the unwanted column using delete-rectangle. It's less fancy than using a regular expression, but easier to do one step at a time, making sure it's doing exactly what you want.

For the sake of completeness, use C-Space to mark one corner of the rectangle, and move to the opposite one. Then you can invoke the command you want on the rectangle defined by the two corners.

Answer 5

Some TeX editors, e.g. WinEdt and TeXnicCenter and also text editors, e.g. Notepad++, offer a rectangular selection feature which is highly useful for editing tables.

For the WinEdt users, this nice and often overlooked functionality is in the Status Line.

If you click on LINE it becomes Block and that switches to the rectangle mode. This allows the user to select rectangular regions and perform copy paste options as usual.

This is especially useful to fill in the missing & columns to tabular data imported from Excel, MATLAB etc. via copying one column of & and pasting it between columns.

TeXnicCenter 2 makes rectangular selections if keys ALT + SHIFT are pressed while selecting. The same is true for Notepad++.

Answer 6

In TeXShop (for Mac Users)
(1) Hold the <option> key down and then click and drag the mouse to select a column.
(2) Cut <command><X> and
(3) Paste <command><V>
to place it as a new column of your table where desired.

Answer 7

In Excel you don't need to use concatenate to keep the table structure. If you import the table as in your MWE, you should be able to keep the & separators and the \\ line breaks in separate columns. Once you swap the columns, you can save it as a tab-delimited .txt file and you are done. The & and \\ will be separated from the data by a tab, but that shouldn't be an issue.

Answer 8

Like emacs, Vim has a column selection mode (^V) which will allow you to select columns and move them about. So ^v {select column} d {move to new location} p. And there's an extension called Tabular which will allow you to reformat tables with ease as well.

Answer 9

You can also use one of Sam Franke’s excellent tools for manipulating delimited text files, CSVed and uniCSVed. Those are true graphical interfaces. You find the programs at this web-page.

Answer 10

Here is a Excel Macro for exporting table content to a latex table. It is not perfect but when prototyping large tables and reordering columns this is quite helpful.

Answer 11

You can do it with ed in a shell script, for example :

#!/bin/sh
ed tab.tex <<END
1,$s/^\([^&]*\)&\([^&]*\)&\([^&]*\)&\([^&]*\)&\([^&]*\)&\([^&\]*\)/\1\&\3\&\2\&\4\&\5\&\6/
w
q
END

Answer 12

In TEXstudio menu, click on 'LaTex' then 'Manipulate Tables' and you can cut and paste columns.