Other ways to distribute space for X columns

[lvjr]

Discussed in #362

^{Originally posted by note286 February 4, 2023}

\documentclass{article}
\usepackage{showframe}
\usepackage{tabularray}
\begin{document}
\begin{table}
\centering
\caption{title}
\begin{tblr}
{
colspec = {*{6}{l}},
% colsep  = 7.5pt,
colsep  = 0pt,
hlines,vlines
}
Lorem     & ipsum      & dolor        & sit     & amet    & consectetur \\
tempor    & incididunt & ut           & labore  & et      & dolore      \\
quis      & nostrud    & exercitation & ullamco & laboris & nisi        \\
consequat & Duis       & aute         & irure   & dolor   & in          \\
cillum    & dolore     & eu           & fugiat  & nulla   & pariatur    \\
proident  & sunt       & in           & culpa   & qui     & officia     \\
\end{tblr}
\end{table}
\end{document}

In the table above, we set colsep = 0pt. I hope tblr can automatically complete the setting of colsep so that the table width is the specified width, such as \textwidth.

I try to set colsep = 7.5pt to meet the demand in this example. But this is inconvenient and not accurate. Whether there is a method to automatically complete this step. If you can provide an interface, such as width = \textwidth, colsep = autofill, it will be even better.

I know the existence of the X column format, but I don't want this. In many cases, the proportion between columns is not easy to see, so it is not very convenient to use the X column format. All I want is to set colsep automatically.

[lvjr]

Issue #100 (about X columns with both co and wd settings) is related.

[lvjr]

@note286 You can use X columns with negative coefficients. The result is similar (but not totally the same) to that of manually setting colsep=7.5pt. See the documentaion of tabu package for how extra space is distributed among X columns.

Also you can use traditional tabular* environment to fill extra spaces. But when there are vertical lines the result is not ideal.

\documentclass{article}
\usepackage{showframe}
\usepackage{tabularray}
\begin{document}

\section{\texttt{tabularray}: minimal width}

\begin{center}
\begin{tblr}{
colspec = {*{6}{l}},
colsep  = 0pt,
hlines,vlines
}
Lorem     & ipsum      & dolor        & sit     & amet    & consectetur \\
tempor    & incididunt & ut           & labore  & et      & dolore      \\
quis      & nostrud    & exercitation & ullamco & laboris & nisi        \\
consequat & Duis       & aute         & irure   & dolor   & in          \\
cillum    & dolore     & eu           & fugiat  & nulla   & pariatur    \\
\end{tblr}
\end{center}

\section{\texttt{tabularray}: calculated \texttt{colsep}}

\begin{center}
\begin{tblr}{
colspec = {*{6}{l}},
colsep  = 7.5pt,
hlines,vlines
}
Lorem     & ipsum      & dolor        & sit     & amet    & consectetur \\
tempor    & incididunt & ut           & labore  & et      & dolore      \\
quis      & nostrud    & exercitation & ullamco & laboris & nisi        \\
consequat & Duis       & aute         & irure   & dolor   & in          \\
cillum    & dolore     & eu           & fugiat  & nulla   & pariatur    \\
\end{tblr}
\end{center}

\section{\texttt{tabularray}: \texttt{X[-1]} columns}

\begin{center}
\begin{tblr}{
colspec = {*{6}{X[l,-1]}},
hlines,vlines
}
Lorem     & ipsum      & dolor        & sit     & amet    & consectetur \\
tempor    & incididunt & ut           & labore  & et      & dolore      \\
quis      & nostrud    & exercitation & ullamco & laboris & nisi        \\
consequat & Duis       & aute         & irure   & dolor   & in          \\
cillum    & dolore     & eu           & fugiat  & nulla   & pariatur    \\
\end{tblr}
\end{center}

\section{\texttt{tabular*}: \texttt{\string\extracolsep}}

\begin{center}
%\setlength\tabcolsep{0pt}
\begin{tabular*}{\linewidth}{@{\extracolsep{\fill}}|*{6}{l|}}
\hline
Lorem     & ipsum      & dolor        & sit     & amet    & consectetur \\
\hline
tempor    & incididunt & ut           & labore  & et      & dolore      \\
\hline
quis      & nostrud    & exercitation & ullamco & laboris & nisi        \\
\hline
consequat & Duis       & aute         & irure   & dolor   & in          \\
\hline
cillum    & dolore     & eu           & fugiat  & nulla   & pariatur    \\
\hline
\end{tabular*}
\end{center}

\end{document}

[lvjr]

I am planning to add a new inner key hspacing which takes the following possible values:

• default: distribute total available space to the widths of X columns.
• fixed: similar to default, but colseps and borders are included into column widths in calculation (#292).
• colsep: distribute extra space to the colseps of X columns (#362).

When hspacing=fixed, users can only use positive coefficients and it is better to make sure rules=smash is also applied (#215). We first subtract half of the widths of the first and last vborders from total width and then distribute remaining width to all columns in proportion to their coefficients.

When hspacing=colsep, users can only use positive coefficients and all cell text must be short.

[note286]

If change the width of paper, I found X[-1] is not not working correctly.

\documentclass{article}
\usepackage[margin=5mm]{geometry}
\usepackage{showframe}
\usepackage{tabularray}
\begin{document}
\section{\texttt{tabularray}: \texttt{X[-1]} columns}
\begin{center}
\begin{tblr}{
colspec = {*{6}{X[l,-1]}},
hlines,vlines
}
Lorem     & ipsum      & dolor        & sit     & amet    & consectetur \\
tempor    & incididunt & ut           & labore  & et      & dolore      \\
quis      & nostrud    & exercitation & ullamco & laboris & nisi        \\
consequat & Duis       & aute         & irure   & dolor   & in          \\
cillum    & dolore     & eu           & fugiat  & nulla   & pariatur    \\
\end{tblr}
\end{center}
\end{document}

---

I read the tabu document and got a certain understanding of using negative number in column X. A positive number means that the column width is fixed, but in the case of a negative number, if the column content width is less than the set width, the natural width will be displayed. This is a example:

\documentclass{article}
\usepackage[margin=5mm]{geometry}
\usepackage{showframe}
\usepackage{tabularray}
\begin{document}
\begin{center}
\begin{tblr}{colspec={X[-1]X[-2]X[1]},hlines,vlines,colsep=0pt}
Lorem ipsum dolor sit amet & consectetur adipisicing elit sed do eiusmod & tempor incididunt ut \\
\end{tblr}
\end{center}

\begin{center}
\begin{tblr}{colspec={X[-1]X[-2]X[1]},hlines,vlines,colsep=0pt}
Lorem ipsum & consectetur adipisicing elit sed do eiusmod labore et dolore magna aliqua Ut enim ad minim veniam & tempor incididunt ut \\
\end{tblr}
\end{center}
\end{document}

Question

When there are positive X columns, everything can be understood. When all column formats are negative, how is the width of each column allocated? For example, the following example makes me very confused.

\documentclass{article}
\usepackage[margin=5mm]{geometry}
\usepackage{showframe}
\usepackage{tabularray}
\begin{document}
\begin{center}
\begin{tblr}{colspec={X[-1]X[-1]X[-1]},hlines,vlines,colsep=0pt}
Lorem ipsum & Lorem ipsum Lorem ipsum & Lorem ipsum \\
\end{tblr}
\end{center}
\end{document}

---

Finally, I'm looking forward to the new inner key hspacing.

[lvjr]

When all column formats are negative, how is the width of each column allocated?

Columns with larger natural widths get more extra space.

You could read chapter 11 of tabu documentation if you are still confused.

[lvjr]

A positive number means that the column width is fixed

Sorry, it turns out that my memory on X columns is inaccurate: when all coefficents of X columns are positive, the column widths are fixed. I have updated my comments above accordingly.

[lvjr]

We can also consider what tabulary package does: distributing widths according to natural widths of columns. See discussion #397.

[fredrikpaues]

We can also consider what tabulary package does: distributing widths according to natural widths of columns. See discussion #397.

Perhaps the column types of the tabulary are so different as to warrant a separate letter? Y?

[HolgerGerhardt]

Finally, I'm looking forward to the new inner key hspacing.

I know I’m a bit late to the party, but I started using the (awesome!) tabularray package only recently.

I realized that I would also appreciate having the envisioned hspacing option.

Currently, there seems to be a single workaround to automatically achieve a uniform distribution of space between columns of natural width when using tabularray-only environments: inserting artificial, empty X columns to separate the actual columns.

This yields exactly the same spacing as the traditional tabular* environment with @{\extracolsep{\fill}}. By contrast, using X[-1] columns leads to slightly different spacing, as @lvjr already pointed out:

\documentclass[11pt, a4paper]{article}

\usepackage{newtx}
\usepackage[T1]{fontenc}

\usepackage[margin = 3cm]{geometry}

\usepackage{caption}
\captionsetup[table]{position = above}

\usepackage{tabularray}
\UseTblrLibrary{siunitx}
\UseTblrLibrary{booktabs}
\SetTblrInner[booktabs]{
  hline{1} = {\heavyrulewidth, solid},
  hborder{1} = {abovespace = \abovetopsep, belowspace = \belowrulesep},
  cells = {font = \small},
  hline{Z} = {\heavyrulewidth, solid},
  hborder{Z} = {abovespace = \aboverulesep, belowspace = \belowbottomsep},
  column{1} = {leftsep = 0pt},
  column{Z} = {rightsep = 0pt},
  width = \textwidth,
}


\begin{document}

\begin{table}[h]
  \caption{A~\texttt{tblr} table with natural-width \texttt{X[-1]}~columns}
  \begin{booktabs}{*{7}{X[-1, l]} l}
    Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 & Test 1234567
  \end{booktabs}
\end{table}

\begin{table}[h]
  \caption{A~\texttt{tblr} table with artificial, empty \texttt{X}~columns inserted between actual columns}
  \begin{booktabs}{
    colspec = {l *{7}{X l}},
    colsep  = 0pt,
  }
    Test & & Test 1 & & Test 12 & & Test 123 & & Test 1234 & & Test 12345 & & Test 123456 & & Test 1234567
  \end{booktabs}
\end{table}

\begin{table}[h]
  \caption{A~traditional \texttt{tabular*} table with \texttt{@\{\textbackslash extracolsep\{\textbackslash fill\}\}}}
  \begin{booktabs}{X}
    \begin{tabular*}{\textwidth}{@{\extracolsep{\fill}} *{7}{l} l @{}}
      Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 & Test 1234567
    \end{tabular*}
  \end{booktabs}
\end{table}

\end{document}

[HolgerGerhardt]

Currently, there seems to be a single workaround to automatically achieve a uniform distribution of space between columns of natural width when using tabularray-only environments: inserting artificial, empty X columns to separate the actual columns.

I have to correct myself. Here is an approach that does not mess with the number of columns in the table:

\documentclass[a4paper]{article}


\usepackage{newtx}
\usepackage[T1]{fontenc}

\usepackage[margin = 3cm]{geometry}

\usepackage{calc}

\usepackage{tabularray}
\UseTblrLibrary{booktabs}

\setlength{\parindent}{0pt}


\begin{document}

{\color{blue} Rule to visualize the \texttt{\textbackslash textwidth} \\
\rule{\textwidth}{0.2cm}}

\newlength{\TblrNaturalWidth}
\newlength{\TblrTotalColSep}
\settowidth{\TblrNaturalWidth}{%
  \begin{booktabs}{
    colspec = {*{8}{l}},
    colsep = 0pt,
  }
    \toprule
    Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 & Test 1234567 \\
    \bottomrule
  \end{booktabs}%
}
\setlength{\TblrTotalColSep}{\textwidth - \TblrNaturalWidth}

\bigskip

\texttt{tblr} (\texttt{booktabs}) environment with \texttt{colsep} calculated from the difference between its natural width and \texttt{\textbackslash textwidth}:

\bigskip

\begin{booktabs}{
  colspec = {*{8}{l}},
  colsep = \TblrTotalColSep / 14,
  column{1} = {leftsep = 0pt},
  column{Z} = {rightsep = 0pt},
}
  \toprule
  Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 & Test 1234567 \\
  \bottomrule
\end{booktabs}%

\bigskip

For comparison, \texttt{tabular*} environment with \texttt{@\{\textbackslash extracolsep\{\textbackslash fill\}\}}:

\bigskip

\begin{tabular*}{\textwidth}{@{\extracolsep{\fill}} *{8}{l} @{}}
  \toprule
  Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 & Test 1234567 \\
  \bottomrule
\end{tabular*}

\end{document}

This yields:

[HolgerGerhardt]

You can, of course, also put this in a command (requires the calc package) such as

\newlength{\TblrNaturalWidth}
\newlength{\TblrTotalColSep}
\newcommand{\booktabsTextwidth}[3]{%
  % Argument 1: #columns across which to distribute the space
  % Argument 2: Layout specifications such as colspec, row, cells, etc.
  % Argument 3: Contents of the table
  \settowidth{\TblrNaturalWidth}{%
    \begin{booktabs}{#2}
      #3
    \end{booktabs}%
  }%
  \setlength{\TblrTotalColSep}{\textwidth - \TblrNaturalWidth}%
  \begin{booktabs}{column{1-Z} = {colsep+ = 0.5\TblrTotalColSep / #1}, #2}
    #3
  \end{booktabs}%
}

Or, even more flexibly:

\newcommand{\BooktabsToWidth}[4][\textwidth]{%
  % Optional argument (#1): desired width, default: \textwidth
  % Mandatory argument (#2): #columns across which to distribute the space
  % Mandatory argument (#3): specifications such as colspec, row, cells, etc.
  % Mandatory argument (#4): contents of the table
  \settowidth{\TblrNaturalWidth}{%
    \begin{booktabs}{#3}
      #4
    \end{booktabs}%
  }%
  \setlength{\TblrTotalColSep}{#1 - \TblrNaturalWidth}%
  \begin{booktabs}{column{1-Z} = {colsep+ = 0.5\TblrTotalColSep / #2}, #3}
    #4
  \end{booktabs}%
}

Here are a few examples typeset with \booktabsTextwidth:

\setlength{\parindent}{0pt}

{\color{blue} Rule to visualize the \texttt{\textbackslash textwidth} \\
\rule{\textwidth}{0.2cm}}

\bigskip

\booktabsTextwidth{7}{
  colspec = {*{7}{|l|}},
}{%
  \toprule
  Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 \\
  \bottomrule
}

\bigskip

\booktabsTextwidth{6}{
  colspec = {*{7}{l}},
  column{1} = {leftsep = 0pt},
  column{Z} = {rightsep = 0pt},
  row{2} = {valign = m},
}{
  \toprule
  Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 \\
  \midrule
  $f(x)$ & $\displaystyle\frac{\sqrt{3}}{n}$ & Test & \SetCell[c=3]{c} Content spanning multiple cells & & & {Row~1 \\ Row~2} \\
  \bottomrule
}

\bigskip

For comparison, \texttt{tabular*} environment with \texttt{@\{\textbackslash extracolsep\{\textbackslash fill\}\}}:

\bigskip

\begin{tabular*}{\textwidth}{@{\extracolsep{\fill}} *{7}{l} @{}}
  \toprule
  Test & Test 1 & Test 12 & Test 123 & Test 1234 & Test 12345 & Test 123456 \\
  \bottomrule
\end{tabular*}