contour(x, y, z, level::Number)
contour(x, y, z, level::Number, VT::Type)

Trace a single contour level, indicated by the argument level. The extracted vertex type maybe be specified by VT.

You'll usually call lines on the output of contour, and then iterate over the result.

contours returns a set of isolines.

You'll usually call levels on the output of contours.

level(c) Indicates the z-value at which the contour level c was traced.

Turns the output of contours into an iterable with each of the traced contour levels. Each of the objects support level, coordinates, and vertices.

lines(c) Extracts an iterable collection of isolines from a contour level. Use coordinates or vertices to get the coordinates of a line.

coordinates(c) Returns the coordinates of the vertices of the contour line as a tuple of lists.

vertices(c)

Returns the vertices of a contour line as a vector of 2-element tuples.

contourlevels(z,n) Examines the values of z and chooses n evenly spaced levels to trace.