some statistics functions

1 files changed, 154 insertions, 0 deletions

diff --git a/chart2/source/tools/StatisticsHelper.cxx b/chart2/source/tools/StatisticsHelper.cxx
new file mode 100644
index 000000000000..e0d1a2ec4a52
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+++ b/chart2/source/tools/StatisticsHelper.cxx
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+/*************************************************************************
+ *
+ *  $RCSfile: StatisticsHelper.cxx,v $
+ *
+ *  $Revision: 1.1 $
+ *
+ *  last change: $Author: bm $ $Date: 2003-12-12 12:37:02 $
+ *
+ *  The Contents of this file are made available subject to the terms of
+ *  either of the following licenses
+ *
+ *         - GNU Lesser General Public License Version 2.1
+ *         - Sun Industry Standards Source License Version 1.1
+ *
+ *  Sun Microsystems Inc., October, 2000
+ *
+ *  GNU Lesser General Public License Version 2.1
+ *  =============================================
+ *  Copyright 2000 by Sun Microsystems, Inc.
+ *  901 San Antonio Road, Palo Alto, CA 94303, USA
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License version 2.1, as published by the Free Software Foundation.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ *  MA  02111-1307  USA
+ *
+ *
+ *  Sun Industry Standards Source License Version 1.1
+ *  =================================================
+ *  The contents of this file are subject to the Sun Industry Standards
+ *  Source License Version 1.1 (the "License"); You may not use this file
+ *  except in compliance with the License. You may obtain a copy of the
+ *  License at http://www.openoffice.org/license.html.
+ *
+ *  Software provided under this License is provided on an "AS IS" basis,
+ *  WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
+ *  WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
+ *  MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
+ *  See the License for the specific provisions governing your rights and
+ *  obligations concerning the Software.
+ *
+ *  The Initial Developer of the Original Code is: Sun Microsystems, Inc.
+ *
+ *  Copyright: 2003 by Sun Microsystems, Inc.
+ *
+ *  All Rights Reserved.
+ *
+ *  Contributor(s): _______________________________________
+ *
+ *
+ ************************************************************************/
+#include "StatisticsHelper.hxx"
+
+#ifndef INCLUDED_RTL_MATH_HXX
+#include <rtl/math.hxx>
+#endif
+
+using ::com::sun::star::uno::Sequence;
+
+namespace
+{
+
+double lcl_getVariance( const Sequence< double > & rData, sal_Int32 & rOutValidCount,
+        bool bUnbiasedEstimator )
+{
+    const sal_Int32 nCount = rData.getLength();
+    rOutValidCount = nCount;
+
+    double fSum = 0.0;
+    double fQuadSum = 0.0;
+
+    for( sal_Int32 i = 0; i < nCount; ++i )
+    {
+        const double fData = rData[i];
+        if( ::rtl::math::isNan( fData ))
+            --rOutValidCount;
+        else
+        {
+            fSum     += fData;
+            fQuadSum += fData * fData;
+        }
+    }
+
+    double fResult;
+    if( rOutValidCount == 0 )
+        ::rtl::math::setNan( & fResult );
+    else
+    {
+        const double fN = static_cast< double >( rOutValidCount );
+        if( bUnbiasedEstimator )
+            fResult = (fQuadSum - fSum*fSum/fN) / (fN - 1);
+        else
+            fResult = (fQuadSum - fSum*fSum/fN) / fN;
+    }
+
+    return fResult;
+}
+
+} // anonymous namespace
+
+namespace chart
+{
+
+// static
+double StatisticsHelper::getVariance(
+    const Sequence< double > & rData,
+    bool bUnbiasedEstimator /* = false */ )
+{
+    sal_Int32 nValCount;
+    return lcl_getVariance( rData, nValCount, bUnbiasedEstimator );
+}
+
+// static
+double StatisticsHelper::getStandardDeviation( const Sequence< double > & rData )
+{
+    double fResult = getVariance( rData );
+    if( ! ::rtl::math::isNan( fResult ))
+        fResult = sqrt( fResult );
+
+    return fResult;
+}
+
+// static
+double StatisticsHelper::getStandardError( const Sequence< double > & rData )
+{
+    sal_Int32 nValCount;
+    double fVar = lcl_getVariance( rData, nValCount, false );
+    double fResult;
+
+    if( nValCount == 0 ||
+        ::rtl::math::isNan( fVar ))
+    {
+        ::rtl::math::setNan( & fResult );
+    }
+    else
+    {
+        // standard-deviation / sqrt(n)
+        fResult = sqrt( fVar ) / sqrt( nValCount );
+    }
+
+    return fResult;
+}
+
+
+} //  namespace chart