figure(fn, w, h) opens a new QPLOT figure with given filename and size.

Sizes may be specified in inches or in millimeters. By default, QPlot uses a heuristic to determine which units you are using: If both w and h are < 25, sizes are understood to be specified in inches, otherwise in millimeters.

Optional argument units may be used to override the interpretation of units. Accepted values are "mm" or "inch".

The unit system introduced here also determines whether dimensions given to subsequent plotting commands are understood to be metric or imperial units.

If h is omitted, h defaults to 3/4 w. If w is also omitted, w defaults to 125 mm (metric).

fn = figure(w, h) opens a new QPlot figure of given size with a temporary filename, which is then returned.