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diff --git a/modules/statistics/macros/perctl.sci b/modules/statistics/macros/perctl.sci
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+// Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
+// Copyright (C) 2000 - INRIA - Carlos Klimann
+// Copyright (C) 2010 - DIGITEO - Yann COLLETTE
+//
+// This file must be used under the terms of the CeCILL.
+// This source file is licensed as described in the file COPYING, which
+// you should have received as part of this distribution.  The terms
+// are also available at
+// http://www.cecill.info/licences/Licence_CeCILL_V2.1-en.txt
+//
+
+function [p]=perctl(x,y)
+
+    //compute the matrix p  of percentils (in increasing  order,
+    //column first) of the real  vector or matrix x indicated by
+    //the entries of  y, the  values of entries   of  y must  be
+    //positive integers between 0 and 100.  p  is a matrix whose
+    //type is length(y)x2 and   the content of its first  column
+    //are the  percentils values.   The contents of   its second
+    //column  are the places  of the computed percentiles in the
+    //input matrix x.
+    //
+    //References:  HYNDMAN,Rob  J.   and  FAN  Yanan,  Sample
+    //Quantiles   in  Statistical   Packages,   The  American
+    //Statistician, Nov.1996, Vol 50, No.4
+    //
+    //fixed: 2006-06-12 ( Pierre MARECHAL, Scilab Team )
+
+    [lhs,rhs]=argn(0)
+    if rhs<>2 then
+        error(msprintf(gettext("%s: Wrong number of input arguments: %d expected.\n"),"perctl",2));
+    end
+    if x==[]|y==[] then p=[];return;end
+    if find((y-int(y)))<>[]|max(y)>100|min(y)<1 then
+        error(msprintf(gettext("%s: Wrong value for input argument #%d: Must be between %d and %d.\n"),"perctl",2,1,100))
+    end
+    if type(x)<>1 then
+        error(msprintf(gettext("%s: Wrong type for input argument #%d: Numerical expected.\n"),"perctl",1))
+    end
+    lenx = size(x)
+    lx   = prod(lenx)
+    [val,pos] = gsort(x)
+    x1 = [matrix(val,lx,1) matrix(pos,lx,1)]
+    x1 = x1(lx-[0:lx-1],:)
+    ly = length(y)
+    y  = gsort((matrix(y,ly,1)/100)*(lx+1))
+    y  = y(ly-[0:ly-1])
+
+    // Now we test if there is enough sample for each asked fractions.
+
+    test1 = find(max(floor(y),1) == 1);
+    y(test1) = 1;
+
+    test2 = find(min(ceil(y),lx) == lx);
+    y(test2) = lx;
+
+    p = x1(floor(y),:)
+    w = find(ceil(y)-floor(y)<>0)
+
+    if w<>[] then
+        p(w,1) = ((x1(ceil(y(w)),1)-x1(floor(y(w)),1)).*(y(w)-floor(y(w)))+x1(floor(y(w)),1));
+    end
+endfunction