The ezcontour and ezcontourf commands use contourplot to generate a 2-D contour plot.  ezcountourf generates a filled contour plot.

When f is not a function of x and y, indets is used to find the indeterminates.  The range limits correspond to the order of alphabetically sorted indeterminates.

xmin, xmax, ymin, and ymax denote the limits of x and y. A short-hand of min and max can be used when xmin = ymin and xmax = ymax.  When omitted, the default range is -Pi..Pi.

Specifying the gridsize option generates a plot over the grid region, gridsize x gridsize.  By default, gridsize is 60.