summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLaurent Balland-Poirier <laurent.balland-poirier@laposte.net>2014-03-05 10:43:54 +0100
committerTomaž Vajngerl <quikee@gmail.com>2014-03-07 06:46:34 -0600
commitcade56eef6d23aa7dd6e374858cf30ff3fcd163b (patch)
tree9c0deb41dcf1f64f03dc0b7a28a8863c012fa04c
parent58d0ba47f82e264e9b17c0e0d37bc043126d195d (diff)
fdo#75538 R^2 calculation of trendline similar to LINEST function
Modify for forced intercept of trendline, calculation of R^2 in the same way as LINEST function does calculation Update fo 4.2 Change-Id: I06ba4e7f5e07f7db150e1bf1070870bf64ad6f61 Reviewed-on: https://gerrit.libreoffice.org/8462 Reviewed-by: Tomaž Vajngerl <quikee@gmail.com> Tested-by: Tomaž Vajngerl <quikee@gmail.com>
-rw-r--r--chart2/source/tools/PolynomialRegressionCurveCalculator.cxx8
1 files changed, 3 insertions, 5 deletions
diff --git a/chart2/source/tools/PolynomialRegressionCurveCalculator.cxx b/chart2/source/tools/PolynomialRegressionCurveCalculator.cxx
index 21b564d63d08..3c15d2831b18 100644
--- a/chart2/source/tools/PolynomialRegressionCurveCalculator.cxx
+++ b/chart2/source/tools/PolynomialRegressionCurveCalculator.cxx
@@ -168,7 +168,6 @@ void SAL_CALL PolynomialRegressionCurveCalculator::recalculateRegression(
double aSumError = 0.0;
double aSumTotal = 0.0;
double aSumYpred2 = 0.0;
- double aSumYactual2 = 0.0;
for( sal_Int32 i = 0; i < aNoValues; i++ )
{
@@ -177,15 +176,14 @@ void SAL_CALL PolynomialRegressionCurveCalculator::recalculateRegression(
double yPredicted = getCurveValue( xValue );
aSumTotal += (yActual - yAverage) * (yActual - yAverage);
aSumError += (yActual - yPredicted) * (yActual - yPredicted);
- aSumYpred2 += yPredicted * yPredicted;
- aSumYactual2 += yActual * yActual;
+ if(mForceIntercept)
+ aSumYpred2 += (yPredicted - mInterceptValue) * (yPredicted - mInterceptValue);
}
double aRSquared = 0.0;
if(mForceIntercept)
{
- if(aSumYactual2 != 0.0)
- aRSquared = aSumYpred2 / aSumYactual2;
+ aRSquared = aSumYpred2 / (aSumError + aSumYpred2);
}
else
{