Add unit tests for chart2 trend calculators

Will be used to check tdf#70673 is fixed. Test will fail before the fix
and should pass after.

Change-Id: I9e0fdc696fb99ac2f0e24b04273391d526c629a6
Reviewed-on: https://gerrit.libreoffice.org/16406
Reviewed-by: Philippe Jung <phil.jung@free.fr>
Tested-by: Philippe Jung <phil.jung@free.fr>

2 files changed, 214 insertions, 0 deletions

diff --git a/chart2/qa/extras/chart2_trendcalculators.cxx b/chart2/qa/extras/chart2_trendcalculators.cxx
new file mode 100644
index 000000000000..7ddb4d80afac
--- /dev/null
+++ b/chart2/qa/extras/chart2_trendcalculators.cxx
@@ -0,0 +1,214 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include "charttest.hxx"
+#include <com/sun/star/chart2/XRegressionCurveContainer.hpp>
+#include <com/sun/star/chart2/XRegressionCurveCalculator.hpp>
+
+// Define the index of sheets in the test document
+#define SHEET_POTENTIAL1          0
+#define SHEET_POTENTIAL2          ( SHEET_POTENTIAL1 + 1)
+#define SHEET_POTENTIAL_LAST      ( SHEET_POTENTIAL2 )
+
+#define SHEET_LINEAR1             ( SHEET_POTENTIAL_LAST + 1 )
+#define SHEET_LINEAR_LAST         ( SHEET_LINEAR1 )
+
+#define SHEET_POLYNOMIAL1         ( SHEET_LINEAR_LAST + 1 )
+#define SHEET_POLYNOMIAL_LAST     ( SHEET_POLYNOMIAL1 )
+
+#define SHEET_EXPONENTIAL1        ( SHEET_POLYNOMIAL_LAST + 1 )
+#define SHEET_EXPONENTIAL2        ( SHEET_EXPONENTIAL1 + 1 )
+#define SHEET_EXPONENTIAL_LAST    ( SHEET_EXPONENTIAL2 )
+
+class Chart2TrendCalculators : public ChartTest
+{
+public:
+    void setUp();
+    void tearDown();
+
+    void testPotentialRegression1();
+    void testPotentialRegression2();
+    void testLinearRegression1();
+    void testPolynomialRegression1();
+    void testExponentialRegression1();
+    void testExponentialRegression2();
+
+    CPPUNIT_TEST_SUITE(Chart2TrendCalculators);
+    CPPUNIT_TEST(testPotentialRegression1);
+    CPPUNIT_TEST(testPotentialRegression2);
+    CPPUNIT_TEST(testLinearRegression1);
+    CPPUNIT_TEST(testPolynomialRegression1);
+    CPPUNIT_TEST(testExponentialRegression1);
+    CPPUNIT_TEST(testExponentialRegression2);
+    CPPUNIT_TEST_SUITE_END();
+
+private:
+
+    Reference<chart2::XRegressionCurve> m_xCurve;
+    Reference< chart2::XRegressionCurveCalculator > m_xRegressionCurveCalculator;
+
+    void loadCalculatorFromSheet(sal_Int32 nSheet);
+    void checkCalculator(
+        Sequence< double > xValues, Sequence< double > yValues,
+        OUString sExpectedFormula );
+
+};
+
+void Chart2TrendCalculators::setUp()
+{
+    ChartTest::setUp();
+    load("/chart2/qa/extras/data/ods/", "trend_calculators.ods");
+}
+
+void Chart2TrendCalculators::tearDown()
+{
+    m_xRegressionCurveCalculator.clear();
+    m_xCurve.clear();
+    ChartTest::tearDown();
+}
+
+void Chart2TrendCalculators::loadCalculatorFromSheet(sal_Int32 nSheet)
+{
+    Reference<chart2::XChartDocument> xChartDoc = getChartDocFromSheet(nSheet, mxComponent);
+    CPPUNIT_ASSERT_MESSAGE("failed to load chart", xChartDoc.is());
+    CPPUNIT_ASSERT(xChartDoc.is());
+
+    Reference<chart2::XDataSeries> xDataSeries = getDataSeriesFromDoc(xChartDoc, 0);
+    CPPUNIT_ASSERT(xDataSeries.is());
+
+    Reference<chart2::XRegressionCurveContainer> xRegressionCurveContainer(xDataSeries, UNO_QUERY_THROW);
+    CPPUNIT_ASSERT( xRegressionCurveContainer.is() );
+
+    Sequence< Reference< chart2::XRegressionCurve > > xRegressionCurveSequence = xRegressionCurveContainer->getRegressionCurves();
+    CPPUNIT_ASSERT_EQUAL((sal_Int32) 1, xRegressionCurveSequence.getLength());
+
+    m_xCurve = xRegressionCurveSequence[0];
+    CPPUNIT_ASSERT(m_xCurve.is());
+
+    m_xRegressionCurveCalculator = m_xCurve->getCalculator();
+    CPPUNIT_ASSERT(m_xRegressionCurveCalculator.is());
+}
+
+void Chart2TrendCalculators::checkCalculator(
+    Sequence< double > xValues, Sequence< double > yValues,
+    OUString sExpectedFormula )
+{
+    m_xRegressionCurveCalculator->recalculateRegression( xValues, yValues );
+    OUString aRepresentation = m_xRegressionCurveCalculator->getRepresentation ();
+    CPPUNIT_ASSERT_EQUAL( sExpectedFormula, aRepresentation );
+    double r2 = m_xRegressionCurveCalculator->getCorrelationCoefficient();
+    CPPUNIT_ASSERT_DOUBLES_EQUAL( 1.0, r2, 1e-8 );
+}
+
+// test y = A x ^ B
+void Chart2TrendCalculators::testPotentialRegression1()
+{
+    loadCalculatorFromSheet( SHEET_POTENTIAL1 );
+    m_xRegressionCurveCalculator->setRegressionProperties( 0, false, 0, 0 );
+    Sequence< double > xValues( 7 );
+    Sequence< double > yValues( 7 );
+    double d;
+    for (int i=0; i<7; i++)
+    {
+        d = (double) i;
+        xValues[i] = d;
+        yValues[i] = 2.0 * pow ( d, 3 );
+    }
+    checkCalculator( xValues, yValues, "f(x) = 2 x^3");
+}
+
+// test y = A x ^ B
+void Chart2TrendCalculators::testPotentialRegression2()
+{
+    loadCalculatorFromSheet( SHEET_POTENTIAL2 );
+    m_xRegressionCurveCalculator->setRegressionProperties( 0, false, 0, 0 );
+    Sequence< double > xValues( 7 );
+    Sequence< double > yValues( 7 );
+    double d;
+    for (int i=0; i<7; i++)
+    {
+        d = (double) i;
+        xValues[i] = d;
+        yValues[i] = -2.0 * pow ( d, 3 );
+    }
+    checkCalculator( xValues, yValues, "f(x) = -2 x^3");
+}
+
+// test y = - 2 X - 5
+void Chart2TrendCalculators::testLinearRegression1()
+{
+    loadCalculatorFromSheet( SHEET_LINEAR1 );
+    m_xRegressionCurveCalculator->setRegressionProperties( 1, false, 0, 0 );
+    Sequence< double > xValues( 7 );
+    Sequence< double > yValues( 7 );
+    double d;
+    for (int i=0; i<7; i++)
+    {
+        d = (double) i;
+        xValues[i] = d;
+        yValues[i] = - 2.0 * d - 5.0 ;
+    }
+    checkCalculator( xValues, yValues, "f(x) =  - 2x - 5");
+}
+
+// test y = A x ^ B
+void Chart2TrendCalculators::testPolynomialRegression1()
+{
+    loadCalculatorFromSheet( SHEET_POLYNOMIAL1 );
+    m_xRegressionCurveCalculator->setRegressionProperties( 2, false, 0, 0 );
+    Sequence< double > xValues( 7 );
+    Sequence< double > yValues( 7 );
+    double d;
+    for (int i=0; i<7; i++)
+    {
+        d = (double) i;
+        xValues[i] = d;
+        yValues[i] =  - 2.0 * d * d + 4 * d - 5;
+    }
+    checkCalculator( xValues, yValues, "f(x) =  - 2x^2 + 4x - 5");
+}
+
+void Chart2TrendCalculators::testExponentialRegression1()
+{
+    loadCalculatorFromSheet( SHEET_EXPONENTIAL1 );
+    m_xRegressionCurveCalculator->setRegressionProperties( 0, false, 0, 0 );
+    Sequence< double > xValues( 7 );
+    Sequence< double > yValues( 7 );
+    double d;
+    for (int i=0; i<7; i++)
+    {
+        d = (double) i;
+        xValues[i] = d;
+        yValues[i] = 2.0 * exp ( 0.3 * d );
+    }
+    checkCalculator( xValues, yValues, "f(x) = 2 exp( 0.3 x )");
+}
+
+void Chart2TrendCalculators::testExponentialRegression2()
+{
+    loadCalculatorFromSheet( SHEET_EXPONENTIAL2 );
+    m_xRegressionCurveCalculator->setRegressionProperties( 0, false, 0, 0 );
+    Sequence< double > xValues( 7 );
+    Sequence< double > yValues( 7 );
+    double d;
+    for (int i=0; i<7; i++)
+    {
+        d = (double) i;
+        xValues[i] = d;
+        yValues[i] = -2.0 * exp ( 0.3 * d );
+    }
+    checkCalculator( xValues, yValues, "f(x) = -2 exp( 0.3 x )");
+}
+
+
+CPPUNIT_TEST_SUITE_REGISTRATION(Chart2TrendCalculators);
+
+CPPUNIT_PLUGIN_IMPLEMENT();
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/chart2/qa/extras/data/ods/trend_calculators.ods b/chart2/qa/extras/data/ods/trend_calculators.ods
new file mode 100644
index 000000000000..fdc5ea42dc9c
--- /dev/null
+++ b/chart2/qa/extras/data/ods/trend_calculators.ods