/usr/share/octave/packages/nan-2.8.1/quantile.m is in octave-nan 2.8.1-1ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 | function Q=quantile(Y,q,DIM,method)
% QUANTILE calculates the quantiles of histograms and sample arrays.
%
% Q = quantile(Y,q)
% Q = quantile(Y,q,DIM)
% returns the q-th quantile along dimension DIM of sample array Y.
% size(Q) is equal size(Y) except for dimension DIM which is size(Q,DIM)=length(Q)
%
% Q = quantile(HIS,q)
% returns the q-th quantile from the histogram HIS.
% HIS must be a HISTOGRAM struct as defined in HISTO2 or HISTO3.
% If q is a vector, the each row of Q returns the q(i)-th quantile
%
% see also: HISTO2, HISTO3, PERCENTILE
% $Id: quantile.m 9601 2012-02-09 14:14:36Z schloegl $
% Copyright (C) 1996-2003,2005,2006,2007,2009,2011 by Alois Schloegl <alois.schloegl@gmail.com>
% This function is part of the NaN-toolbox
% http://pub.ist.ac.at/~schloegl/matlab/NaN/
% This program is free software; you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation; either version 3 of the License, or
% (at your option) any later version.
%
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
% GNU General Public License for more details.
%
% You should have received a copy of the GNU General Public License
% along with this program; If not, see <http://www.gnu.org/licenses/>.
if nargin<3,
DIM = [];
end;
if isempty(DIM),
DIM = find(size(Y)>1,1);
if isempty(DIM), DIM = 1; end;
end;
if nargin<2,
help quantile
else
[q, rix] = sort(q(:)'); % sort quantile values
[tmp,rix] = sort(rix); % generate reverse index
SW = isstruct(Y);
if SW, SW = isfield(Y,'datatype'); end;
if SW, SW = strcmp(Y.datatype,'HISTOGRAM'); end;
if SW,
[yr, yc] = size(Y.H);
Q = repmat(nan,length(q),yc);
if ~isfield(Y,'N');
Y.N = sum(Y.H,1);
end;
for k1 = 1:yc,
tmp = Y.H(:,k1)>0;
h = full(Y.H(tmp,k1));
t = Y.X(tmp,min(size(Y.X,2),k1));
N = Y.N(k1);
t2(1:2:2*length(t)) = t;
t2(2:2:2*length(t)) = t;
x2 = cumsum(h);
x(1)=0;
x(2:2:2*length(t)) = x2;
x(3:2:2*length(t)) = x2(1:end-1);
% Q(q < 0 | 1 < q,:) = NaN; % already done at initialization
Q(q==0,k1) = t2(1);
Q(q==1,k1) = t2(end);
n = 1;
for k2 = find( (0 < q) & (q < 1) )
while (q(k2)*N > x(n)),
n=n+1;
end;
if q(k2)*N==x(n)
% mean of upper and lower bound
Q(k2,k1) = (t2(n)+t2(n+1))/2;
else
Q(k2,k1) = t2(n);
end;
end;
Q = Q(rix,:); % order resulting quantiles according to original input q
end;
elseif isnumeric(Y),
sz = size(Y);
if DIM>length(sz),
sz = [sz,ones(1,DIM-length(sz))];
end;
f = zeros(1,length(q));
f( (q < 0) | (1 < q) ) = NaN;
D1 = prod(sz(1:DIM-1));
D3 = prod(sz(DIM+1:length(sz)));
Q = repmat(nan,[sz(1:DIM-1),length(q),sz(DIM+1:length(sz))]);
for k = 0:D1-1,
for l = 0:D3-1,
xi = k + l * D1*sz(DIM) + 1 ;
xo = k + l * D1*length(q) + 1;
t = Y(xi:D1:xi+D1*sz(DIM)-1);
t = t(~isnan(t));
N = length(t);
if (N==0)
f(:) = NaN;
else
t = sort(t);
t2(1:2:2*length(t)) = t;
t2(2:2:2*length(t)) = t;
x = floor((1:2*length(t))/2);
%f(q < 0 | 1 < q) = NaN; % for efficiency its defined outside loop
f(q==0) = t2(1);
f(q==1) = t2(end);
n = 1;
for k2 = find( (0 < q) & (q < 1) )
while (q(k2)*N > x(n)),
n = n+1;
end;
if q(k2)*N==x(n)
% mean of upper and lower bound
f(k2) = (t2(n) + t2(n+1))/2;
else
f(k2) = t2(n);
end;
end;
end;
Q(xo:D1:xo + D1*length(q) - 1) = f(rix);
end;
end;
else
fprintf(2,'Error QUANTILES: invalid input argument\n');
return;
end;
end;
%!assert(quantile(1:10,[.2,.5]),[2.5, 5.5])
|