color – Why does tabularray not Accept Colors from Commands in LaTeX?

colortabularray

I try to set the color of a cell in a tabularray by a command:

\documentclass{article}

\usepackage{xcolor}
\usepackage{tabularray}

\ExplSyntaxOn

\newcommand{\Tcolor}{
    green
}

\ExplSyntaxOff


\begin{document}
    \textcolor{\Tcolor}{abc}
    
\begin{tblr}{
        colspec  = {l},
        cell{1}{1} = {\Tcolor},
    }
abc  \\
\end{tblr}

\end{document}

Somehow the color cell{1}{1} = {\Tcolor}, breaks. Why?

cell{1}{1} = {green}, works…

EDIT: I guess in my attempt to create a MWE I shortened it too much. There is a need for a function instead of a simple color:

\documentclass{article}

\usepackage{xcolor}
\usepackage{tabularray}

\ExplSyntaxOn


\newcommand{\Tcolor}[1]{
    \int_compare:nNnTF
    {#1} = {0}
    { red } 
    {
        \int_compare:nNnTF
        {#1} < {30}
        { orange } 
        {
            \int_compare:nNnTF
            {#1} < {40}
            { green } 
            {
                blue
            }
        }
    }
    
}

\ExplSyntaxOff


\begin{document}
    \textcolor{\Tcolor{32}}{abc}
    
\begin{tblr}{
        colspec  = {l},
        cell{1}{1} = {\Tcolor{32}},
        cell{1}{2} = {\Tcolor{48}}, 
    }
abc  \\
def \\
\end{tblr}

\end{document}

Best Answer

The cell{<i>}{<j>} key can accept several types of values; for instance, according to the manual, you can do

cell{1}{1}={cmd=\fbox}

Thus the managing of values is necessarily complex. When a value is just a string that's not another key, it is interpreted as a color name for the background.

You can use bg=<color> and, in this case, you can use a macro.

\documentclass{article}

\usepackage{xcolor}
\usepackage{tabularray}

\ExplSyntaxOn

\NewExpandableDocumentCommand{\Tcolor}{m}
  {
    \bool_case:nF
      {
        { \int_compare_p:n {#1 = 0} }{ red!80 } 
        { \int_compare_p:n {0 < #1 < 30} }{ orange } 
        { \int_compare_p:n {30 <= #1 < 40} }{ green!80 }
      }
      { blue!60!green }
  }

\ExplSyntaxOff

\begin{document}

\textcolor{\Tcolor{32}}{abc}

\medskip
    
\begin{tblr}{
   colspec  = {l},
   cell{1}{1} = {bg=\Tcolor{0}},
   cell{2}{1} = {bg=\Tcolor{15}}, 
   cell{3}{1} = {bg=\Tcolor{32}}, 
   cell{4}{1} = {bg=\Tcolor{48}}, 
}
abc \\
def \\
ghi \\
jkl \\
\end{tblr}

\end{document}

Note the use of \bool_case:nF in order to avoid the awkward nesting of conditionals.

Related Solutions

fonts,graphics,pdftex,color – Resolve Conflict Between Color, Graphicx, and Libertine

These option clashes happen when a package is requested to be loaded on two different positions, like by you and inside another package, but with different options. The package is loaded by the first \usepackage (or its twin \RequirePackage); it isn't loaded again when it is requested again. It simply can't be loaded a second time. Therefore the new options can be activated and previous options might conflict with the second usage. So LaTeX creates an error to report this issue to you.

The way to fix this is to declare the options beforehand using \PassOptionsToPackage{<options>}{<package>}. Then they are used wherever the package is loaded.

\documentclass{article}
\usepackage{ifpdf}
\ifpdf
    \PassOptionsToPackage{pdftex,usenames,dvipsnames}{color}
    \usepackage[T1]{fontenc}
    \usepackage{libertine} % most likely loads 'color' itself
    %\usepackage{lmodern} % doesn't load 'color'
    \usepackage{color}
    \usepackage[pdftex]{graphicx}
\else
    %\bye
\fi
\begin{document}
Hello, world!
\end{document}

I can't test it by myself, because I don't have the libertine package installed.

PS:

I don't think you need to set pdftex manually. Normally packages do a good job recognizing the driver by themselves. Also you might want to use the extended xcolor package instead of color.

TikZ-PGF – Drawing Angled Lines for Calligraphy Templates

You can use polar coordinates such as (55:100cm). In the code below, I compute the precise number of oblique lines to draw in function of the chosen angle \myAngle and the distance \myDist between two consecutive oblique lines. My code also computes the largest length needed for these lines.

\documentclass[a4paper]{article}
\usepackage{tikz}
\usetikzlibrary{calc}

\pagestyle{empty}

\newcommand*{\myDist}{1cm} % distance between consecutive oblique lines
\newcommand*{\myAngle}{55} % angle of said lines wrt horizontal, in degrees
% Distance between consecutive oblique lines, projected on the horizontal axis
\pgfmathsetlengthmacro{\horizIntervWidth}{\myDist/sin(\myAngle)}

% Length of the longest oblique lines we'll need. I add 10pt to be 100% safe
% with respect to rounding errors (the lines will be clipped anyway).
\pgfmathsetlengthmacro{\maxLength}{10pt + \paperheight/sin(\myAngle)}

% Number of oblique lines to draw
\pgfmathtruncatemacro{\maxIndex}{
  round((\paperheight/tan(\myAngle) + \paperwidth)/\horizIntervWidth)}

\begin{document}

\begin{tikzpicture}[remember picture, overlay]
% Just to be sure we don't paint outside the page. :-)
\clip (current page.south west) rectangle (current page.north east);

\foreach \i in {1,2,...,30} {
  \draw[black] ($(current page.north west)+(0,-\i)$) --
               ($(current page.north east)+(0,-\i)$);
}

\foreach \i in {0.5,1.5,...,60} {
  \draw[lightgray] ($(current page.north west)+(0,-\i)$) --
                   ($(current page.north east)+(0,-\i)$);
}

\foreach \i in {1,2,...,\maxIndex} {
  \draw[red] ([xshift=-\i*\horizIntervWidth]current page.south east) --
            +(\myAngle:\maxLength);
}
\end{tikzpicture}

\end{document}

Best Answer

Related Solutions

fonts,graphics,pdftex,color – Resolve Conflict Between Color, Graphicx, and Libertine

PS:

TikZ-PGF – Drawing Angled Lines for Calligraphy Templates

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