Cfrgtkky

Is there a table package which automatically calculates the needed number of columns? Take for example this:

documentclass{article}



usepackage{pgf}

usepackage{siunitx}

usepackage{xinttools}



begin{document}





deflist{0,0.5,1,2.5,3,4.5,8}

deff(#1){#1^2}

defpf(#1){pgfmathparse{f(#1)}num[round-precision=1,round-mode=places]{pgfmathresult}}





begin{tabular}{l|*{100}{c}} % Just choose 100, practically enough columns... but this ist not very elegant

  $x$ & xintFor #1 in list do { & $#1$} \hline

  $f(x)$ & xintFor #1 in list do { & $pf(#1)$}

end{tabular}



end{document}

I can just choose 101 row numbers (large enough for pracical purposes), but this doesn't seem to be the correct way to do this. So is there any package which doesn't require the number of columns for this example?

using some large number in a * column repeat isn't so bad, it's how amsmath matrix avoids the need to specify columns, however if you want to access TeX's primitive feature of a && meaning to repeat all following column specifications as often as needed then you can do something like

documentclass{article}



usepackage{pgf}

usepackage{siunitx}

usepackage{xinttools}



begin{document}



makeatletter

newcolumntype{?}{!{d@llarend&span@gobbletwo}}

makeatother



deflist{0,0.5,1,2.5,3,4.5,8}

deff(#1){#1^2}

defpf(#1){pgfmathparse{f(#1)}num[round-precision=1,round-mode=places]{pgfmathresult}}





begin{tabular}{l|?c}

  $x$ & xintFor #1 in list do { & $#1$} \hline

  $f(x)$ & xintFor #1 in list do { & $pf(#1)$}

end{tabular}



end{document}