diff options
| author | Laurent Balland-Poirier <laurent.balland-poirier@laposte.net> | 2014-03-01 00:20:53 +0100 |
|---|---|---|
| committer | Tomaž Vajngerl <quikee@gmail.com> | 2014-03-03 11:15:05 -0600 |
| commit | 00cb825ab3f16a94f1e8311ba0c24f72588e788e (patch) | |
| tree | 3df796c5e9182730c69d29380d641faf2f052072 | |
| parent | 6a71b8d902ae24db1251ea65841dd0f7bfa5e9b3 (diff) | |
fdo#75538 R^2 calculation for trendline similar to LINEST function
Modify for forced intercept of trendline, calculation of R^2 in the same
way as LINEST function does calculation
Change-Id: Ic943b1ca1bbe30b1a4b88e2a338eb9dc34d848b6
Reviewed-on: https://gerrit.libreoffice.org/8402
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>
Tested-by: Tomaž Vajngerl <quikee@gmail.com>
| -rw-r--r-- | chart2/source/tools/PolynomialRegressionCurveCalculator.cxx | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/chart2/source/tools/PolynomialRegressionCurveCalculator.cxx b/chart2/source/tools/PolynomialRegressionCurveCalculator.cxx index 90be5a163af5..9b39e01b25f9 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 { |