title: Gnuplot Thick Curve Exceeds Plot Boundary
body: <p>I've plotted the following in Gnuplot.  My issue is that the curves exceed the boundary (so we can see that the purple and blue curves go beyond the y-axis).  Any way to solve this problem?  I'm hoping there is something that restricts drawing to inside the plotting area.  Sure I can just plot less of the curve but that then looks weird.  Ideally, I want Gnuplot to go around the frame of the curve and remove any bits of the curve that are there.</p>
  
  <p>I've made the purple curve abnormally fat just to illustrate the problem.  The problem is also there with the blue curve though.</p>
  
  <p><img src="https://i.stack.imgur.com/AsIIi.png" alt="Graph"></p>
  
  <p>The code to produce the above plot is:</p>
  
  <pre><code>#!/usr/bin/env gnuplot
  
  ### n: change this parameter to equal the number of data sets to be plotted
  n = 2
  # t: top margin in pixels
  t = 25.0
  # b: key height in pixels (bottom margin)
  b = 25.0
  # h: height of output in pixels
  h = 150.0*n + t + b
  
  ### define functions to help set top/bottom margins
  top(i,n,h,t,b) = 1.0 - (t+(h-t-b)*(i-1)/n)/h
  bot(i,n,h,t,b) = 1.0 - (t+(h-t-b)*i/n)/h
  
  ### first set up some basic plot parameters
  #set term cairolatex size 15cm,15cm
  #set output 'DifferentialAmplifierPlot.tex'
  
  set term pdfcairo size 15cm,15cm
  set output 'DifferentialAmplifierPlot.pdf'
  
  set border lw 4
  
  set grid mxtics mytics xtics ytics ls '-1' ls '-1' lc rgb 'gray70', lc rgb 'gray90'
  
  set mxtics
  set mytics
  
  # Make yrange &gt; ytics &gt; function to get padding.
  set yrange [-1.5:1.5]
  set ytics ("" -1.5, -1.25 1, -1.0, -0.75 1, -0.5, -0.25 1, 0.0, 0.25 1, 0.5, 0.75 1, 1.0, 1.25 1, "" -1.5)
  
  set xtics 0,1,5
  set xrange [0:5]
  
  set xtics
  set mxtics
  set mytics
  
  set format x ""
  set grid xtics ytics mxtics mytics ls -1 ls -1 lc rgb 'gray60', lc rgb '#C0E5E5E5''
  
  set multiplot layout (n+1),1 #font ",14" title 'Input And Output Voltages Of Differential Amplifier'
  
  ### First plot
  # change only plot command here
  currentplot = 1
  set tmargin at screen top(currentplot,n,h,t,b)
  set bmargin at screen bot(currentplot,n,h,t,b)
  unset key
  unset xlabel
  set title 'Input (Bottom) And Output (Top) Voltages Of The Differential Amplifier'
  set ylabel 'Voltage [V]'
  plot 'DifferentialAmplfier.dat' using (1000*$1):2 with lines lw 20 lc rgb 'dark-magenta'
  
  ### Last plot
  # change only plot command here
  currentplot = currentplot + 1
  set tmargin at screen top(currentplot,n,h,t,b)
  set bmargin at screen bot(currentplot,n,h,t,b)
  set format x
  unset title
  set xlabel 'Time [ms]'
  set ylabel 'Voltage [mV]'
  plot 'DifferentialAmplfier.dat' using (1000*$1):(1000*$3) with lines lw 10 lc rgb 'navy'
  
  unset multiplot
  
  set term x11
  </code></pre>
  
  <p>Questionable/Dodgy fix...</p>
  
  <p><img src="https://i.stack.imgur.com/0A1lZ.png" alt="GraphDodgyFix"></p>