% -*- texinfo -*-
% @deftypefn {Function File} {} pareto (@var{x})
% @deftypefnx {Function File} {} pareto (@var{x}, @var{y})
% @deftypefnx {Function File} {} pareto (@var{h}, @dots{})
% @deftypefnx {Function File} {@var{h} =} pareto (@dots{})
% Draw a Pareto chart, also called ABC chart. A Pareto chart is a bar graph
% used to arrange information in such a way that priorities for process
% improvement can be established. It organizes and displays information
% to show the relative importance of data. The chart is similar to the
% histogram or bar chart, except that the bars are arranged in decreasing
% order from left to right along the abscissa.
%
% The fundamental idea (Pareto principle) behind the use of Pareto
% diagrams is that the majority of an effect is due to a small subset of the
% causes, so for quality improvement the first few (as presented on the
% diagram) contributing causes to a problem usually account for the majority
% of the result. Thus, targeting these 'major causes' for elimination
% results in the most cost-effective improvement scheme.
%
% The data are passed as @var{x} and the abscissa as @var{y}. If @var{y} is
% absent, then the abscissa are assumed to be @code{1 : length (@var{x})}.
% @var{y} can be a string array, a cell array of strings or a numerical
% vector.
%
% An example of the use of @code{pareto} is
%
% @example
% @group
% Cheese = @{'Cheddar', 'Swiss', 'Camembert', ...
% 'Munster', 'Stilton', 'Blue'@};
% Sold = [105, 30, 70, 10, 15, 20];
% pareto(Sold, Cheese);
% @end group
% @end example
% @end deftypefn