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C++ API

: h = convhulln (pts)
: h = convhulln (pts, options)
: [h, v] = convhulln (…)

Compute the convex hull of the set of points pts.

pts is a matrix of size [n, dim] containing n points in a space of dimension dim.

The hull h is an index vector into the set of points and specifies which points form the enclosing hull.

An optional second argument, which must be a string or cell array of strings, contains options passed to the underlying qhull command. See the documentation for the Qhull library for details http://www.qhull.org/html/qh-quick.htm#options. The default options depend on the dimension of the input:

  • 2D, 3D, 4D: options = {"Qt"}
  • 5D and higher: options = {"Qt", "Qx"}

If options is not present or [] then the default arguments are used. Otherwise, options replaces the default argument list. To append user options to the defaults it is necessary to repeat the default arguments in options. Use a null string to pass no arguments.

If the second output v is requested the volume of the enclosing convex hull is calculated.

See also: convhull, delaunayn, voronoin.

Package: octave