prPrepareAlign(align, x, rnames, default_rn = "l")paste(rep('c',ncol(x)),collapse='') to center. Valid alignments are
l = left, c = center and r = right. You can also specify align='c|c' and
other LaTeX tabular formatting. If you want to set the alignment of the
rownames this string needst to be ncol(x) + 1, otherwise it automatically
pads the string with a left alignment for the rownames.print and knit_print
it takes a string of the class htmlTable as x argument.htmlTable: prAddCells,
prAddSemicolon2StrEnd,
prGetCgroupHeader,
prGetRowlabelPos, prGetStyle,
prPrepareCgroup, prTblNo