# How to plot implicit defined graphs? - Gnuplot Programming

### How to plot implicit defined graphs?

- Implicit graphs are plotted indirectly.

- The following example illustrates the process:

gnuplot>

gnuplot> function(x,y) = y - x**2 / tan(y)

gnuplot> set contour base

gnuplot> set cntrparam levels discrete 0.0

gnuplot> unset surface

gnuplot> set table 'graphcurves.dat'

gnuplot> splot function(x,y)

gnuplot> unset table

gnuplot> plot 'graphcurves.dat' w l

- The function() sets the coordinates.

- The contour graph is defined in ‘graphcurves.dat’ file.

- ‘splot’ executes the function.

- ‘plot’ places the graph in the file ‘graphcurves.dat’ file.