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-rw-r--r--scaddins/source/analysis/financial.cxx35
1 files changed, 28 insertions, 7 deletions
diff --git a/scaddins/source/analysis/financial.cxx b/scaddins/source/analysis/financial.cxx
index 309f044da2d3..c51f4e984de8 100644
--- a/scaddins/source/analysis/financial.cxx
+++ b/scaddins/source/analysis/financial.cxx
@@ -541,16 +541,37 @@ double SAL_CALL AnalysisAddIn::getXirr(
// Newton's method - try to find a fResultRate, so that lcl_sca_XirrResult() returns 0.
sal_Int32 nIter = 0;
- bool bContLoop;
+ double fResultValue;
+ sal_Int32 nIterScan = 0;
+ bool bContLoop = false;
+ bool bResultRateScanEnd = false;
+
+ // First the inner while-loop will be executed using the default Value fResultRate
+ // or the user guessed fResultRate if those do not deliver a solution for the
+ // Newton's method then the range from -0.99 to +0.99 will be scanned with a
+ // step size of 0.01 to find fResultRate's value which can deliver a solution
do
{
- double fResultValue = lcl_sca_XirrResult( aValues, aDates, fResultRate );
- double fNewRate = fResultRate - fResultValue / lcl_sca_XirrResult_Deriv1( aValues, aDates, fResultRate );
- double fRateEps = fabs( fNewRate - fResultRate );
- fResultRate = fNewRate;
- bContLoop = (fRateEps > fMaxEps) && (fabs( fResultValue ) > fMaxEps);
+ if (nIterScan >=1)
+ fResultRate = -0.99 + (nIterScan -1)* 0.01;
+ do
+ {
+ fResultValue = lcl_sca_XirrResult( aValues, aDates, fResultRate );
+ double fNewRate = fResultRate - fResultValue / lcl_sca_XirrResult_Deriv1( aValues, aDates, fResultRate );
+ double fRateEps = fabs( fNewRate - fResultRate );
+ fResultRate = fNewRate;
+ bContLoop = (fRateEps > fMaxEps) && (fabs( fResultValue ) > fMaxEps);
+ }
+ while( bContLoop && (++nIter < nMaxIter) );
+ nIter = 0;
+ if ( ::rtl::math::isNan(fResultRate) || ::rtl::math::isInf(fResultRate)
+ ||::rtl::math::isNan(fResultValue) || ::rtl::math::isInf(fResultValue))
+ bContLoop = true;
+
+ ++nIterScan;
+ bResultRateScanEnd = (nIterScan >= 200);
}
- while( bContLoop && (++nIter < nMaxIter) );
+ while(bContLoop && !bResultRateScanEnd);
if( bContLoop )
throw css::lang::IllegalArgumentException();