How do I make a frame around a PlotLegend?

Questions
1

I apologize in advance because this must be trivial, but I cannot figure out how to get a frame or border around my PlotLegend. Here is the line in Plot

PlotLegends -> {Placed[{"q", "q/a"}, {0.8, 0.9}]}

I tried using LegendFunction → Framed anywhere I could put it, all it did is print a legend called
“LegendFunction → Framed” .

Generally , if something is the least bit tricky, I find the solution with an internet search, so this must be obvious, but if someone can take me out of my misery I would be most grateful.

–aryeh

2

Hi there! Can you post an image of the output in Mathematica? I need to see your whole code to help you

3

Thank you for your quick response. I added that part of the notebook as a code sample.
I think that it will generate the plot in question. When posting a code segment like this, is there a way to run it so that the output is also attached?
Best regards
–aryeh

`Manipulate[
 pl5 = plotType[{(x ) (1/q)/Sqrt[(1 - (x)^2 )^2 + (x)^2 (1/q)^2   ],
    (x ) (1/q)/Sqrt[(1 - (x)^2 )^2 + (x)^2 (a/q)^2   ]}, {x, 
    lowerLimit, upperLimit}, 
   GridLines -> {{{1, {Thick, Red}}, {1 - 1/(2 q), {Blue, Thick, 
        Dashed}}, {1 + 1/(2 q), {Blue, Thick, Dashed}},
       {1 - a /(2 q), {Green, Thick, Dashed}}, {1 + a/(2 q), {Green, 
        Thick, Dashed}}}, { {1/Sqrt[2], {Thick, Red}}}}, 
   PlotRange -> {{lowerLimit, upperLimit}, {0, 1}},
   LabelStyle -> {FontSize -> 16, FontFamily -> "Times", Black, 
     Bold},
   PlotLegends -> {Placed[{Row[{"Q=", q}], Row[{"Q=", q/a}]}, {0.8, 
       0.9}]},
   PlotStyle -> {Blue, Green}, Frame -> True,  
   FrameLabel -> {None, 
     "\!\(\*SubscriptBox[\(V\), \(R\)]\)/\!\(\*SubscriptBox[\(V\), \
\(IN\)]\)"}];
 pl6 = plotType[{1/Sqrt[(1 - (x)^2 )^2 + (x)^2 (1/q)^2   ],
    1/Sqrt[(1 - (x)^2 )^2 + (x)^2 (a/q)^2   ]}, {x, lowerLimit, 
    upperLimit}, 
   GridLines -> {{{1, {Thick, Red}}, {1 - 1/(2 q), {Blue, Thick, 
        Dashed}}, {1 + 1/(2 q), {Blue, Thick, Dashed}},
       {1 - a /(2 q), {Green, Thick, Dashed}}, {1 + a/(2 q), {Green, 
        Thick, Dashed}}}, { {1/Sqrt[2], {Thick, Red}}}}, 
   PlotRange -> {{lowerLimit, upperLimit}, {0, q}},
   LabelStyle -> {FontSize -> 16, FontFamily -> "Times", Black, 
     Bold},
   PlotLegends -> {Placed[{Row[{"Q=", q}], Row[{"Q=", q/a}]}, {0.8, 
       0.9}]},
   PlotStyle -> {Blue, Green}, Frame -> True,  
   FrameLabel -> {None, 
     "\!\(\*SubscriptBox[\(V\), \(C\)]\)/\!\(\*SubscriptBox[\(V\), \
\(IN\)]\)" }];
 pl7 = plotType[{x^2/Sqrt[(1 - (x)^2 )^2 + (x)^2 (1/q)^2   ],
    x^2/Sqrt[(1 - (x)^2 )^2 + (x)^2 (a/q)^2   ]}, {x, lowerLimit, 
    upperLimit}, 
   GridLines -> {{{1, {Thick, Red}}, {1 - 1/(2 q), {Blue, Thick, 
        Dashed}}, {1 + 1/(2 q), {Blue, Thick, Dashed}},
       {1 - a /(2 q), {Green, Thick, Dashed}}, {1 + a/(2 q), {Green, 
        Thick, Dashed}}}, { {1/Sqrt[2], {Thick, Red}}}}, 
   PlotRange -> {{lowerLimit, upperLimit}, {0, q}},
   LabelStyle -> {FontSize -> 16, FontFamily -> "Times", Black, 
     Bold},
   PlotLegends -> {Placed[{Row[{"Q=", q}], Row[{"Q=", q/a}]}, {0.8, 
       0.9}]},
   PlotStyle -> {Blue, Green}, Frame -> True,  
   FrameLabel -> {"NORMALIZED FREQUENCY", 
     "\!\(\*SubscriptBox[\(V\), \(L\)]\)/\!\(\*SubscriptBox[\(V\), \
\(IN\)]\)" }];
  GraphicsGrid[{{pl5}, {pl6}, {pl7}}, ImageSize -> {750, 1500}],
 {{q, 5}, 0.25, 50}, {{a, 5}, 0.1, 
  50}, {plotType, {LogLinearPlot, Plot}}, {{upperLimit, 100}, {1.2, 
   1.5, 2, 5, 10, 100}}, {{lowerLimit, 0.01}, {0.01, 0.1, 0.5, 0.8}},
 
 
 SaveDefinitions -> True]`
4

Hi Aryeh, the code looks fine to me. What version of Mathematica are you using? In this situation, by Occam’s razor, I will say to you that you need to install the package PlotLegend. if it is installed then try to use the option LegendBorder in PlotLegend instead of Frame. Tell me if this works for you.

Kind regards

5

I am using Mathematica 12.
PlotLegend is listed as obsolete, and its functionality is supposed to be built in.
I am worried about having a package that may conflict with built in functions.
I think I need to learn how to use LegendFunction → Framed
but I cannot figure out where to put it in PlotLegend.

6

Got it. The following code works, though I think that there must be an easier way.

PlotLegends -> 
 Placed[LineLegend[{Blue, Green}, {Row[{"Q=", q}], Row[{"Q=", q/a}]}, 
   LegendFunction -> Framed], {0.8, 0.9}],
7

Nice to hear that.

8

Hi Aryeh,

There is no need to duplicate the colors

PlotLegends -> 
  Placed[LineLegend[{Row[{"Q=", q}], Row[{"Q=", q/a}]}, 
    LegendFunction -> "Frame"], {Right, Top}]]
9

Thank you. That works, and {Right, Top} is better than my absolute placement.