Graphics, Figures & Tables ⇒ Specify Width of columns in tabular

[Eenzc]

Hello,

I have the following table:

Code: Select all

\begin{table} [H]
\begin{center}
\begin{tabular}{|c|r@{}l|r@{}l|r@{}l|}
\hline
Electrode & \multicolumn{2}{c|}{Radius} & \multicolumn{2}{c|}{Charge Passed to plate Hg}
 & \multicolumn{2}{c|}{Hg Mass} \\
% & & & & & & & & \\
\hline
P4 		& \SI{500}{} & \SI{}{\mu m} & \SI{1}{} 			&	\SI{}{C}			& \SI{1}{} 			&\SI{}{mg}		 \\
Set 1 & \SI{500}{} & \SI{}{\mu m} & \SI{1}{} 			&	\SI{}{C}			& \SI{1}{}			&\SI{}{mg}		 \\
Set 2 & \SI{250}{} & \SI{}{\mu m} & \SI{125}{} 		&	\SI{}{mC} 		& \SI{130}{}		&\SI{}{\mu g}	 \\
Set 3 & \SI{100}{} & \SI{}{\mu m}	& \SI{8}{} 			&	\SI{}{mC} 		& \SI{8}{}			&\SI{}{\mu g}\\
Set 4 & \SI{50}{} & \SI{}{\mu m} 	& \SI{1}{} 			&	\SI{}{mC} 		& \SI{1}{}			&\SI{}{\mu g}\\
Set 5 & \SI{20}{} & \SI{}{\mu m}	& \SI{64}{} 		&	\SI{}{\mu C} 	& \SI{67}{}			&\SI{}{ng}	 \\
Set 6 & \SI{10}{} & \SI{}{\mu m}	& \SI{8}{} 			& \SI{}{\mu C} 	& \SI{8}{}			&\SI{}{ng}	 \\
\hline
\end{tabular}
\caption{Test Table: Values for electrodeposition of a flattened hemi-sphere of Hg onto electrode arrays of defined radii, Hg mass values calculated to 2 significant figures (each electrode within the array considered independent).}
\label{Table:ElectrodeHgMasses}
\end{center}
\end{table}

I would like to specify the widths of the visble columns to be 3cm each

Ie : | 3cm | 1.5cm : 1.5cm | 1.5cm : 1.5cm | 1.5cm : 1.5cm |

Is there an easy way to do this? I've done a bit of searching but couldn't find a simple answer.

Thanks

[localghost]

Those basics are listed in lshort. The array package has some enhancements to the tabular environment.


Best regards
Thorsten¹

[phi]

You can use the column type p{3cm}. But it would be much better to put the units into the header and use an S column for the numbers. Replace \SI{x}{} by \num{x} and \SI{}{x} by \si{x}. Don't use the center environment inside the table environment, rather use \centering. If you use siunitx, which is recommended for typesetting for typesetting numbers, units and quantities, make sure that you have read the manual carefully, especially the sections 4, 5, 7 and 21.
Here is a much better version of your table:

Code: Select all

\documentclass{article}

\usepackage{lmodern}
\usepackage{textcomp}
\usepackage[T1]{fontenc}
\usepackage{booktabs}
\usepackage{siunitx}

\sisetup{unitmode=text}

\begin{document}

\begin{table}
\centering
\begin{tabular}{cS[tabformat=3]S[tabformat=3e-1]S[tabformat=3e-1]}
\toprule
Electrode & {Radius (\si{\micrometre})} & {Charge Passed to plate Hg (\si{\milli\coulomb})} & {Hg Mass (\si{\microgram})} \\
\midrule
P4    & 500 &   1e3  &   1e3  \\
Set 1 & 500 &   1e3  &   1e3  \\
Set 2 & 250 & 125    & 130    \\
Set 3 & 100 &   8    &   8    \\
Set 4 &  50 &   1    &   1    \\
Set 5 &  20 &  64e-3 &  67e-3 \\
Set 6 &  10 &   8e-3 &   8e-3 \\
\bottomrule
\end{tabular}
\caption{Test Table: Values for electrodeposition of a flattened hemi-sphere of Hg onto electrode arrays of defined radii, Hg mass values calculated to 2 significant figures (each electrode within the array considered independent).}
\label{Table:ElectrodeHgMasses}
\end{table}

\end{document}