How to get rid of unwanted white space using Manipulate Plot

Question

I'm trying to make the next simple interactive plot:

Needs["PlotLegends`"]
rTE[\[Theta]_, n1_, n2_] := 
 Abs[(n1*Cos[\[Theta]] - 
     n2*Cos[ArcSin[n1*Sin[\[Theta]]/n2]])/(n1*Cos[\[Theta]] + 
     n2*Cos[ArcSin[n1*Sin[\[Theta]]/n2]])]
rTM[\[Theta]_, n1_, n2_] := 
 Abs[(n2*Cos[\[Theta]] - 
     n1*Cos[ArcSin[n1*Sin[\[Theta]]/n2]])/(n2*Cos[\[Theta]] + 
     n1*Cos[ArcSin[n1*Sin[\[Theta]]/n2]])]
tTE[\[Theta]_, n1_, n2_] := 
 Abs[(2*n1*Cos[\[Theta]])/(n1*Cos[\[Theta]] + 
     n2*Cos[ArcSin[n1*Sin[\[Theta]]/n2]])]
tTM[\[Theta]_, n1_, n2_] := 
 Abs[(2*n1*Cos[\[Theta]])/(n2*Cos[\[Theta]] + 
     n1*Cos[ArcSin[n1*Sin[\[Theta]]/n2]])]
RTE[\[Theta]_, n1_, n2_] := Abs[(rTE[\[Theta], n1, n2])^2]
RTM[\[Theta]_, n1_, n2_] := Abs[(rTM[\[Theta], n1, n2])^2]
TTE[\[Theta]_, n1_, n2_] := 
 Abs[(tTE[\[Theta], n1, n2])^2*(n2*
      Cos[ArcSin[n1*Sin[\[Theta]]/n2]])/(n1*Cos[\[Theta]])]
TTM[\[Theta]_, n1_, n2_] := 
 Abs[(tTM[\[Theta], n1, n2])^2*(n2*
      Cos[ArcSin[n1*Sin[\[Theta]]/n2]])/(n1*Cos[\[Theta]])]
Manipulate[
 GraphicsRow[{Plot[{rTM[\[Theta], n1, n2], rTE[\[Theta], n1, n2], 
     tTM[\[Theta], n1, n2], tTE[\[Theta], n1, n2]}, {\[Theta], 
     0, \[Pi]/2}, PlotStyle -> Thick, 
    PlotLegend -> {"rTM[\[Theta]]" , "rTE[\[Theta]]", 
      "tTM[\[Theta]]" , "tTE[\[Theta]]"}, LegendPosition -> {1, -0.4},
     PlotMarkers -> Automatic, AxesLabel -> Automatic, 
    PlotRange -> {0, 1}], 
   Plot[{RTM[\[Theta], n1, n2], RTE[\[Theta], n1, n2], 
     TTM[\[Theta], n1, n2], TTE[\[Theta], n1, n2]}, {\[Theta], 
     0, \[Pi]/2}, PlotStyle -> Thick, 
    PlotLegend -> {"RTM[\[Theta]]" , "RTE[\[Theta]]", 
      "TTM[\[Theta]]" , "TTE[\[Theta]]"}, LegendPosition -> {1, -0.4},
     PlotMarkers -> Automatic, AxesLabel -> Automatic, 
    PlotRange -> {0, 1}]}, ImageSize -> 800, Frame -> All, 
  Spacings -> {0, -300}], {n1, 1, 3.6}, {n2, 1, 3.6}, 
 ImageMargins -> Tiny, ControlType -> InputField, Alignment -> Top]

I don't have enough reputation to post the outcome image but you can see it here:

https://dl.dropboxusercontent.com/u/21949826/picture.png

As you can see - there is too much white space above and below the plots. How can I get rid of this?

Thanks!

Answer 1

It is often easier to use Grid than GraphicsGrid (or GraphicsRow). Thy this:

Manipulate[
 Grid[{{Plot[{rTM[\[Theta], n1, n2], rTE[\[Theta], n1, n2], 
      tTM[\[Theta], n1, n2], tTE[\[Theta], n1, n2]}, {\[Theta], 
      0, \[Pi]/2}, PlotStyle -> Thick, 
     PlotLegend -> {"rTM[\[Theta]]", "rTE[\[Theta]]", "tTM[\[Theta]]",
        "tTE[\[Theta]]"}, LegendPosition -> {1, -0.4}, 
     AxesLabel -> Automatic, PlotRange -> {0, 1}, ImageSize -> 400],
    Plot[{RTM[\[Theta], n1, n2], RTE[\[Theta], n1, n2], 
      TTM[\[Theta], n1, n2], TTE[\[Theta], n1, n2]}, {\[Theta], 
      0, \[Pi]/2}, PlotStyle -> Thick, 
     PlotLegend -> {"RTM[\[Theta]]", "RTE[\[Theta]]", "TTM[\[Theta]]",
        "TTE[\[Theta]]"}, LegendPosition -> {1, -0.4}, 
     AxesLabel -> Automatic, PlotRange -> {0, 1}, 
     ImageSize -> 400]}}], {n1, 1, 3.6}, {n2, 1, 3.6}, 
 ControlType -> InputField, Alignment -> Top]