[Tex/LaTex] Pgfplotstable: format all cells but header row and header column

Question

I found some code to asign colors to table values with PGFplotstable,
but unfortunately it is only designed for tables where the topmost row is a head row (which is ignored by postproc). I also need the first column to be ignored by postproc – probably realtively simple but I just cant find how to do it.

This is the code:

\pgfplotstableset{
    color cells/.style={
        col sep=comma,
        string type,
        postproc cell content/.code={%
                \pgfkeysalso{@cell content=\rule{0cm}{2.4ex}%
                \pgfmathsetmacro\y{min(100,max(0,abs(round(##1 * 0.5))))}%
                \ifnum##1<0\edef\temp{\noexpand\cellcolor{blue!\y}}\temp\fi%
                \ifnum##1>0\edef\temp{\noexpand\cellcolor{red!\y}}\temp\fi%
                \pgfmathtruncatemacro\x\y%
                \ifnum\x>50 \color{white}\fi%
                ##1}%
                }
    }
}

\begin{table}\caption{Correlation or something}
\centering
\pgfplotstabletypeset[color cells]{
a,b,c,d
x,-300,-200,-100
y,0,100,200
z,300,40,800
}
\end{table}

(original source is: Drawing heatmaps using TikZ)

The code does not work, as the values in the first column are not numbers – i just want to ignore them, leaving those cells as they are.

Answer 1

Ahhh I found it, pretty simple actually: I start the tabe with the attribute 'columns/a/.style={reset styles,string type}' :

\pgfplotstabletypeset[color cells, columns/a/.style={reset styles,string type}]

Where 'a' is the name of my first column !

Hope this helps someone else ;)