1## Copyright (C) 2007, 2008, 2009 David Bateman
2## Copyright (C) 2003 Alberto Terruzzi
4## This file is part of Octave.
6## Octave is free software; you can redistribute it and/or modify it
7## under the terms of the GNU General Public License as published by
8## the Free Software Foundation; either version 3 of the License, or (at
9## your option) any later version.
11## Octave is distributed in the hope that it will be useful, but
12## WITHOUT ANY WARRANTY; without even the implied warranty of
13## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14## General Public License for more details.
16## You should have received a copy of the GNU General Public License
17## along with Octave; see the file COPYING. If not, see
18## <http://www.gnu.org/licenses/>.
21## @deftypefn {Function File} {} pareto (@var{x})
22## @deftypefnx {Function File} {} pareto (@var{x}, @var{y})
23## @deftypefnx {Function File} {} pareto (@var{h}, @dots{})
24## @deftypefnx {Function File} {@var{h} =} pareto (@dots{})
25## Draw a Pareto chart, also called ABC chart. A Pareto chart is a bar graph
26## used to arrange information in such a way that priorities for process
27## improvement can be established. It organizes and displays information
28## to show the relative importance of data. The chart is similar to the
29## histogram or bar chart, except that the bars are arranged in decreasing
30## order from left to right along the abscissa.
32## The fundamental idea (Pareto principle) behind the use of Pareto
33## diagrams is that the majority of an effect is due to a small subset of the
34## causes, so for quality improvement the first few (as presented on the
35## diagram) contributing causes to a problem usually account for the majority
36## of the result. Thus, targeting these "major causes" for elimination
37## results in the most cost-effective improvement scheme.
39## The data are passed as @var{x} and the abscissa as @var{y}. If @var{y} is
40## absent, then the abscissa are assumed to be @code{1 : length (@var{x})}.
41## @var{y} can be a string array, a cell array of strings or a numerical
44## An example of the use of @code{pareto} is
48## Cheese = @{"Cheddar", "Swiss", "Camembert", ...
49## "Munster", "Stilton", "Blue"@};
50## Sold = [105, 30, 70, 10, 15, 20];
51## pareto(Sold, Cheese);
56function h = pareto (varargin)
58 if (nargin != 1 && nargin != 2)
62 x = varargin {1}(:).';
64 y = varargin {2}(:).';
69 y = cellfun (@(x) num2str (x), num2cell (y), "UniformOutput", false);
73 y = cellfun (@(x) int2str (x), num2cell (1 : numel(x)),
74 "UniformOutput", false);
77 [x, idx] = sort (x, "descend");
83 idx95 = find(sign(cdf95(1:end-1)) != sign(cdf95(2:end)))(1);
85 [ax, hbar, hline] = plotyy (1 : idx95, x (1 : idx95),
86 1 : length(cdf), 100 .* cdf,
89 axis (ax(1), [1 - 0.6, idx95 + 0.6, 0, maxcdf]);
90 axis (ax(2), [1 - 0.6, idx95 + 0.6, 0, 100]);
91 set (ax(2), "ytick", [0, 20, 40, 60, 80, 100],
92 "yticklabel", {"0%", "20%", "40%", "60%", "80%", "100%"});
93 set (ax(1), "xtick", 1 : idx95, "xticklabel", y (1: idx95));
94 set (ax(2), "xtick", 1 : idx95, "xticklabel", y (1: idx95));
104%! colormap (jet (64))
105%! Cheese = {"Cheddar", "Swiss", "Camembert", "Munster", "Stilton", "Blue"};
106%! Sold = [105, 30, 70, 10, 15, 20];
107%! pareto(Sold, Cheese);
111%! % Suppose that we want establish which products makes 80 % of turnover.
112%! Codes = {"AB4","BD7","CF8","CC5","AD11","BB5","BB3","AD8","DF3","DE7"};
113%! Value = [2.35 7.9 2.45 1.1 0.15 13.45 5.4 2.05 0.85 1.65]';
114%! SoldUnits = [54723 41114 16939 1576091 168000 687197 120222 168195, ...
116%! pareto (Value.*SoldUnits, Codes);
