Drawing line in notebook with Mathematica command

Question

I have a for loop that makes plots iteratively, in between the plots, I would like to draw a line in the notebook. Is there a command that is the equivalent of doing this:

https://reference.wolfram.com/language/workflow/InsertAHorizontalLineInANotebook.html

Answer 1

There's many ways to achieve something like this, but a start for programmatically creating a line to go across your notebook would be something like this:

CellPrint[
 Cell["", "Text", Editable -> False, Selectable -> False, 
  CellFrame -> {{0, 0}, {0, 0.5}}, ShowCellBracket -> False, 
  CellMargins -> {{0, 0}, {1, 1}}, 
  CellElementSpacings -> {"CellMinHeight" -> 1}, 
  CellFrameMargins -> 0, CellFrameColor -> RGBColor[0, 0, 1], 
  CellSize -> {Inherited, 3}]]

Of course the options can be edited, if you want it thicker, a different color, etc...

Hope this helps!

Answer 2

An alternative approach is to print the cells with graphics contents with a line at the bottom:

ClearAll[thickLineBelow]
thickLineBelow = CellPrint[ExpressionCell[#, "Output", CellFrame -> {{0, 0}, {3, 0}}, 
     CellFrameColor -> RGBColor[0, 0, 1]]] &;

You can wrap each graphics object you produce in the loop with thickLineBelow:

thickLineBelow /@ {Plot[Sin[x], {x, 0, 2 Pi}, AspectRatio -> 1/4], 
   Row[Framed /@ {Graphics[{Red, Disk[]}, ImageSize -> 100], 
      Plot[x Sin[x], {x, 0, 5 Pi}, ImageSize -> 200]}, Spacer[10]], 
   MatrixPlot[RandomReal[1, {5, 30}], ImageSize -> 300]};