A problem with correct filling for ListPlot and InterpolationOrder 0

Question

Using ListPlot I can generate with

ListPlot[{{344.41, 272.2, 280}, {345, 223, 278}}, InterpolationOrder -> 0, PlotRange -> {200, 400}, Joined -> True]

a simple Plot.

However, if I now use a the "Filling" option Mathematica (12.1) displays the following wrong result.

ListPlot[{{344.41, 272.2, 280}, {345, 223, 278}}, InterpolationOrder -> 0, PlotRange -> {200, 400}, Joined -> True, Filling -> {1 -> {{2}, {Blue}}} ]

As far as I get it, the problem might arrise from the decimals. Is there a known solution for that?

Answer 1

Two work-arounds:

1. Use ListPlot without the filling option and post-process the output to add the filling polygons as Epilog:

lp = ListPlot[{{344.41, 272.2, 280}, {345, 223, 278}}, 
  InterpolationOrder -> 0, PlotRange -> {200, 400}, Joined -> True]; 

Show[lp, 
  Epilog -> {Opacity[.5, LightBlue], 
    Polygon @ Join[#, Reverse @ #2] & @@ Cases[lp, Line[x_, ___] :> x, All]}]

Alternatively, use FilledCurve instead of Polygon:

Show[lp, 
   Epilog -> {Opacity[.5, LightBlue], 
      FilledCurve @ ({#, Reverse /@ #2} & @@ Cases[lp, _Line, All])}]

2. Rationalizeing input data for some choice of the second argument also works:

ListPlot[Rationalize[{{344.41, 272.2, 280}, {345, 223, 278}}, 10^-2], 
 InterpolationOrder -> 0, PlotRange -> {200, 400}, Joined -> True, 
 Filling -> {1 -> {2}}]

Caveat: Need to automate the second argument of Rationalize based on input data.