title: How to plot a particular solution in the form f(x,y)=0 on Gnuplot
body: <p>I need to plot a two variable function on Gnuplot when it intersects with 0, that is: f(x,y)=0. It will mean a 2D plot rather than 3D.
  My attempt up to now is:</p>
  <pre><code>set term cairolatex eps standalone size 6in,6in lw 7
  set key box opaque samplen 6
  set key spacing 1.5
  set key Right
  set key height 2
  set key width 3
  f(x,y)=...
  set output 'V.tex'
  plot f(x,y)=0 title '\small${\hat{V}=2}$' lc rgb &quot;black&quot;
  set out
  </code></pre>
  <p>but it returns <em>function to plot expected</em>.</p>
  <p>Just in case, the <em>workaround</em> given in 5.2 section of the Gnuplot FAQ in <code>http://www.gnuplot.info/faq/faq.html</code> does not produce a .tex file that I can compile.</p>