Vertically center contents of table cell

Consider the following example:

\documentclass{article}

\usepackage{booktabs}

\psset{
unit = 0.7,
dimen = middle,
ticks = none,
labels = none
}

\newcommand*\pind[2]{%
\psset{linecolor = red}
\psline(#1,0)(#1,#2)
\psline(!#1 0.2 sub #2)(!#1 0.2 add #2)
}
\newcommand*\enkeltobservationer{%
\begin{pspicture}(-0.5,-0.2)(5.9,6.3)
\psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]
\pind{0.5}{3}
\pind{1.0}{5}
\pind{1.5}{3}
\pind{2.0}{3}
\pind{2.5}{4}
\pind{3.0}{2}
\pind{3.5}{5}
\pind{4.0}{1}
\pind{4.5}{4}
\pind{5.0}{2}
\end{pspicture}%
}
\newcommand*\soejle[2]{%
\psset{fillcolor = red}
\psframe[fillstyle = solid](!#1 0.5 sub 0)(#1,#2)
}
\newcommand*\intervaller{%
\begin{pspicture}(-0.5,-0.2)(5.9,6.3)
\psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]
\soejle{0.5}{3}
\soejle{1.0}{5}
\soejle{1.5}{3}
\soejle{2.0}{3}
\soejle{2.5}{4}
\soejle{3.0}{2}
\soejle{3.5}{5}
\soejle{4.0}{1}
\soejle{4.5}{4}
\soejle{5.0}{2}
\end{pspicture}%
}

\begin{document}

\begin{table}
\centering
\begin{tabular}{l c c c}
\toprule
Begreb               &
Forkortelse          &
Enkeltobservationer  &
Intervaller            \\
\midrule
Hyppighed            &
$h(x)$               &
\enkeltobservationer &
\intervaller           \\
\bottomrule
\end{tabular}
\end{table}

\end{document}

I would like to vertically center Hyppighed and $h(x)$ relative to the figures; how do I do that?

-
Does this help: tex.stackexchange.com/a/147393/18228? – Herr K. Nov 30 '13 at 0:55
@KevinC I cannot get it to work. Can I make you give an answer? :) – Svend Tveskæg Nov 30 '13 at 1:03
@DonutE.Knot And I think your comment is arrogant. – Svend Tveskæg Nov 30 '13 at 1:18
I can't get your code to compile... There's some error with the command \clipbox being already defined. But take a look at this, it might help: tex.stackexchange.com/a/46390/18228 – Herr K. Nov 30 '13 at 1:24

You can do this with the m{} column of array package. I have demonstrated two ways below. First one using m column and second one using tabularx with array package. egreg's answer comes handy here. Both m and X columns make the contents left anigned (they are just minipages). If you want them centered you can add >{\centering\arraybackslash} in their declarations as in the code below.

\documentclass{article}
\usepackage[a4paper,margin=2cm]{geometry}
\usepackage{booktabs,array,,tabularx,calc}

\psset{
unit = 0.7,
dimen = middle,
ticks = none,
labels = none
}

\newcommand*\pind[2]{%
\psset{linecolor = red}
\psline(#1,0)(#1,#2)
\psline(!#1 0.2 sub #2)(!#1 0.2 add #2)
}
\newcommand*\enkeltobservationer{%
\begin{pspicture}(-0.5,-0.2)(5.9,6.3)
\psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]
\pind{0.5}{3}
\pind{1.0}{5}
\pind{1.5}{3}
\pind{2.0}{3}
\pind{2.5}{4}
\pind{3.0}{2}
\pind{3.5}{5}
\pind{4.0}{1}
\pind{4.5}{4}
\pind{5.0}{2}
\end{pspicture}%
}
\newcommand*\soejle[2]{%
\psset{fillcolor = red}
\psframe[fillstyle = solid](!#1 0.5 sub 0)(#1,#2)
}
\newcommand*\intervaller{%
\begin{pspicture}(-0.5,-0.2)(5.9,6.3)
\psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]
\soejle{0.5}{3}
\soejle{1.0}{5}
\soejle{1.5}{3}
\soejle{2.0}{3}
\soejle{2.5}{4}
\soejle{3.0}{2}
\soejle{3.5}{5}
\soejle{4.0}{1}
\soejle{4.5}{4}
\soejle{5.0}{2}
\end{pspicture}%
}

\begin{document}

\begin{table}
\centering
\begin{tabular}{l c
>{\centering\arraybackslash}m{.35\linewidth}
>{\centering\arraybackslash}m{.35\linewidth}}
\toprule
Begreb               &
Forkortelse          &
Enkeltobservationer  &
Intervaller            \\
\midrule
Hyppighed            &
$h(x)$               &
\enkeltobservationer &
\intervaller           \\
\bottomrule
\end{tabular}
\end{table}

\begin{center}
\renewcommand{\tabularxcolumn}[1]{m{#1}}
\begin{tabularx}{\textwidth}{m{\widthof{Hyppighed}}
>{\centering\arraybackslash}m{\widthof{Forkortelse}}
>{\centering\arraybackslash}X
>{\centering\arraybackslash}X}    %%% \widthof from calc package
\toprule
Begreb               &
Forkortelse          &
Enkeltobservationer  &
Intervaller            \\
\midrule
Hyppighed            &
$h(x)$               &                %%% \centering added to declaration above
\enkeltobservationer &
\intervaller           \\
\bottomrule
\end{tabularx}
\end{center}

\end{document}

-
Nice. Thank you. – Svend Tveskæg Nov 30 '13 at 10:01
The last 2 titles are not centered. – kiss my armpit Nov 30 '13 at 12:49
@DonutE.Knot As your wish sir :-) – Harish Kumar Dec 1 '13 at 0:41
Thank you madam for the update. :-) – kiss my armpit Dec 1 '13 at 0:53
@DonutE.Knot hihi, but it is not madam – Harish Kumar Dec 1 '13 at 0:59

As what I said in the comment, it is very very easy (as I have done this kind of table many times). :-)

\documentclass[preview,border=12pt,12pt]{standalone}
\usepackage[a4paper,margin=2cm]{geometry}
\usepackage{array}
\usepackage{booktabs}

\newcolumntype{A}[3]{%
>{\minipage{\dimexpr#1\linewidth-#2\tabcolsep-#3\arrayrulewidth}\vspace\tabcolsep}%
c
<{\vspace\tabcolsep\endminipage}}

\psset
{
unit = 0.7,
dimen = middle,
ticks = none,
labels = none
}

\newcommand*\pind[2]{%
\psset{linecolor = red}
\psline(#1,0)(#1,#2)
\psline(!#1 0.2 sub #2)(!#1 0.2 add #2)
}
\newcommand*\enkeltobservationer{%
\begin{pspicture}(-0.5,-0.2)(5.9,6.3)
\psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]
\pind{0.5}{3}
\pind{1.0}{5}
\pind{1.5}{3}
\pind{2.0}{3}
\pind{2.5}{4}
\pind{3.0}{2}
\pind{3.5}{5}
\pind{4.0}{1}
\pind{4.5}{4}
\pind{5.0}{2}
\end{pspicture}%
}
\newcommand*\soejle[2]{%
\psset{fillcolor = red}
\psframe[fillstyle = solid](!#1 0.5 sub 0)(#1,#2)
}
\newcommand*\intervaller{%
\begin{pspicture}(-0.5,-0.2)(5.9,6.3)
\psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]
\soejle{0.5}{3}
\soejle{1.0}{5}
\soejle{1.5}{3}
\soejle{2.0}{3}
\soejle{2.5}{4}
\soejle{3.0}{2}
\soejle{3.5}{5}
\soejle{4.0}{1}
\soejle{4.5}{4}
\soejle{5.0}{2}
\end{pspicture}%
}

\begin{document}

\begin{tabular}{A{0.15}{2}{1.5} >{\centering}A{0.15}{2}{1} >{\centering}A{0.35}{2}{1} >{\centering}A{0.35}{2}{1.5}}
\toprule
Begreb               &
Forkortelse          &
Enkeltobservationer  &
Intervaller            \tabularnewline\hline
\midrule
Hyppighed                      &
$h(x)$               &
\enkeltobservationer &
\intervaller                   \tabularnewline\hline
\bottomrule
\end{tabular}

\end{document}

With vertical and horizontal lines

The magic numbers in A{...}{...}{...} will be explained later if requested.

-