Graphics legend: How do I split tables into parts?

Question

Using Jens's code:

data = Map[AccountingForm, gedreht , {-1}];
result = Framed@
   Row[{end, 
     Grid[Transpose[{Range@Length@data, 
         Map[AccountingForm, data, {2}]}] /. {x_, {y__}} -> {x, y}, 
      Frame -> All]}];
hdr = {{"Berechnete Koordinaten", SpanFromLeft, SpanFromLeft}, {"Nr.",
     "x", "y"}};
legendmarkers = Range@Length@data;
legendlabels = 
  Map[Style[AccountingForm[#, 10], FontSize -> 20, 
     FontFamily -> "Calibri"] &, data, {-1}];
hdr[[2]] = 
  Style[#, Bold, FontSize -> 22, FontFamily -> "Calibri"] & /@ 
   hdr[[2]];
hdr[[1, 1]] = 
  Style[hdr[[1, 1]], Bold, FontSize -> 26, FontFamily -> "Calibri"];
legendGrd = 
  Grid[hdr~Join~
    Transpose[Join[{legendmarkers}, Transpose[legendlabels]]], 
   Frame -> All, 
   BaseStyle -> {FontSize -> 20, FontFamily -> "Calibri"}, 
   FrameStyle -> GrayLevel[.9], Alignment -> {Center, Center}, 
   Background -> {None, {GrayLevel[.5], 
      GrayLevel[.5], {GrayLevel[.8]}}}];
plan = Panel@Row[{end, legendGrd}, Spacer[5]]

I sometimes get pretty huge tables for the legend of a figure:

How can I split this table in subtables of, say, 20 lines and to arrange them horizontally?

Thanks a lot!!

Answer 1

ClearAll[divideTblF, gridF];
(* a function to re-arrange an n-by-m list into an r-by-(m n / r) list:   *)
divideTblF[table_List, rows_Integer] :=  Module[{dims = Dimensions[table], r},
r = Min[rows, First@dims];
 Flatten /@ Transpose[Partition[table, r, r, 1, {ConstantArray[Null, Last@dims]}]]];
(* grid with legend and column headers added to the input table: *)
gridF[x_, legendheader_, colheaders_, opts : OptionsPattern[]] :=
Grid[Join[{{legendheader, SpanFromLeft},
  colheaders[[Mod[Range[Last@Dimensions[x]], Length[colheaders], 1]]]}, x],
   FilterRules[{opts}, Options[Grid]]];

Update: a more elegant alternative to Flatten/@Transpose[...] is to use Join[##,2]&@@(...):

 divideTblF2[table_List, rows_Integer] := Module[{dims = Dimensions[table], 
       r = Min[rows, First@Dimensions[table]] },
    Join[##, 2] & @@ (Partition[table, r, r, 1, {ConstantArray[Null, Last@dims]}])]

Examples:

dataTable = {{11, 12, 13}, {21, 22, 23}, {31, 32, 33}, {41, 42, 43},
  {51, 52, 53}, {61, 62, 63}};
dataTable // Grid

Column[#, Spacer[5], Frame -> All] &@
  (gridF[divideTblF[dataTable, #], "legend", {"col1", "col2", "col3"},
      Dividers -> All] & /@ {6, 5, 4, 3, 2})