Hello, I'm working on improvements on trend line equation and I proposed a commit: https://gerrit.libreoffice.org/18397/ I noticed that there are some differences between RegressionCurveCalculators: 1. LogarithmicRegressionCurveCalculator is using "fabs()" http://opengrok.libreoffice.org/xref/core/chart2/source/tools/LogarithmicRegressionCurveCalculator.cxx#141 but PolynomialRegressionCurveCalculator is using "std::abs()" http://opengrok.libreoffice.org/xref/core/chart2/source/tools/PolynomialRegressionCurveCalculator.cxx#258 Which one is better? 2. RegressionCalculationHelper.hxx defines two unicode constants. #define UC_MINUS_SIGN (sal_Unicode('-')) opengrok.libreoffice.org/xref/core/chart2/source/inc/RegressionCalculationHelper.hxx#29 But they are only used is LogarithmicRegressionCurveCalculator.cxx. opengrok.libreoffice.org/xref/core/chart2/source/tools/LogarithmicRegressionCurveCalculator.cxx#159 Other RegressionCurveCalculators do not use them Should these #define be removed or should they be used by other RegressionCurveCalculators? Best regards, Laurent BP ----- LibreOffice 4.3.6.2 -- View this message in context: http://nabble.documentfoundation.org/Trend-line-differences-between-RegressionCurveCalculators-tp4161350.html Sent from the Dev mailing list archive at Nabble.com.