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2 *
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 *
20 *************************************************************/
21
22
23
24 // MARKER(update_precomp.py): autogen include statement, do not remove
25 #include "precompiled_chart2.hxx"
26 #include "LinearRegressionCurveCalculator.hxx"
27 #include "macros.hxx"
28 #include "RegressionCalculationHelper.hxx"
29
30 #include <rtl/math.hxx>
31 #include <rtl/ustrbuf.hxx>
32
33 using namespace ::com::sun::star;
34
35 using ::rtl::OUString;
36 using ::rtl::OUStringBuffer;
37
38 namespace chart
39 {
40
LinearRegressionCurveCalculator()41 LinearRegressionCurveCalculator::LinearRegressionCurveCalculator() :
42 m_fSlope( 0.0 ),
43 m_fIntercept( 0.0 )
44 {
45 ::rtl::math::setNan( & m_fSlope );
46 ::rtl::math::setNan( & m_fIntercept );
47 }
48
~LinearRegressionCurveCalculator()49 LinearRegressionCurveCalculator::~LinearRegressionCurveCalculator()
50 {}
51
52 // ____ XRegressionCurveCalculator ____
recalculateRegression(const uno::Sequence<double> & aXValues,const uno::Sequence<double> & aYValues)53 void SAL_CALL LinearRegressionCurveCalculator::recalculateRegression(
54 const uno::Sequence< double >& aXValues,
55 const uno::Sequence< double >& aYValues )
56 throw (uno::RuntimeException)
57 {
58 RegressionCalculationHelper::tDoubleVectorPair aValues(
59 RegressionCalculationHelper::cleanup(
60 aXValues, aYValues,
61 RegressionCalculationHelper::isValid()));
62
63 const size_t nMax = aValues.first.size();
64 if( nMax == 0 )
65 {
66 ::rtl::math::setNan( & m_fSlope );
67 ::rtl::math::setNan( & m_fIntercept );
68 ::rtl::math::setNan( & m_fCorrelationCoeffitient );
69 return;
70 }
71
72 const double fN = static_cast< double >( nMax );
73 double fSumX = 0.0, fSumY = 0.0, fSumXSq = 0.0, fSumYSq = 0.0, fSumXY = 0.0;
74 for( size_t i = 0; i < nMax; ++i )
75 {
76 fSumX += aValues.first[i];
77 fSumY += aValues.second[i];
78 fSumXSq += aValues.first[i] * aValues.first[i];
79 fSumYSq += aValues.second[i] * aValues.second[i];
80 fSumXY += aValues.first[i] * aValues.second[i];
81 }
82
83 m_fSlope = (fN * fSumXY - fSumX * fSumY) / ( fN * fSumXSq - fSumX * fSumX );
84 m_fIntercept = (fSumY - m_fSlope * fSumX) / fN;
85
86 m_fCorrelationCoeffitient = ( fN * fSumXY - fSumX * fSumY ) /
87 sqrt( ( fN * fSumXSq - fSumX * fSumX ) *
88 ( fN * fSumYSq - fSumY * fSumY ) );
89 }
90
getCurveValue(double x)91 double SAL_CALL LinearRegressionCurveCalculator::getCurveValue( double x )
92 throw (lang::IllegalArgumentException,
93 uno::RuntimeException)
94 {
95 double fResult;
96 ::rtl::math::setNan( & fResult );
97
98 if( ! ( ::rtl::math::isNan( m_fSlope ) ||
99 ::rtl::math::isNan( m_fIntercept )))
100 {
101 fResult = m_fSlope * x + m_fIntercept;
102 }
103
104 return fResult;
105 }
106
getCurveValues(double min,double max,::sal_Int32 nPointCount,const uno::Reference<chart2::XScaling> & xScalingX,const uno::Reference<chart2::XScaling> & xScalingY,::sal_Bool bMaySkipPointsInCalculation)107 uno::Sequence< geometry::RealPoint2D > SAL_CALL LinearRegressionCurveCalculator::getCurveValues(
108 double min, double max, ::sal_Int32 nPointCount,
109 const uno::Reference< chart2::XScaling >& xScalingX,
110 const uno::Reference< chart2::XScaling >& xScalingY,
111 ::sal_Bool bMaySkipPointsInCalculation )
112 throw (lang::IllegalArgumentException,
113 uno::RuntimeException)
114 {
115 if( bMaySkipPointsInCalculation &&
116 isLinearScaling( xScalingX ) &&
117 isLinearScaling( xScalingY ))
118 {
119 // optimize result
120 uno::Sequence< geometry::RealPoint2D > aResult( 2 );
121 aResult[0].X = min;
122 aResult[0].Y = this->getCurveValue( min );
123 aResult[1].X = max;
124 aResult[1].Y = this->getCurveValue( max );
125
126 return aResult;
127 }
128 return RegressionCurveCalculator::getCurveValues( min, max, nPointCount, xScalingX, xScalingY, bMaySkipPointsInCalculation );
129 }
130
ImplGetRepresentation(const uno::Reference<util::XNumberFormatter> & xNumFormatter,::sal_Int32 nNumberFormatKey) const131 OUString LinearRegressionCurveCalculator::ImplGetRepresentation(
132 const uno::Reference< util::XNumberFormatter >& xNumFormatter,
133 ::sal_Int32 nNumberFormatKey ) const
134 {
135 OUStringBuffer aBuf( C2U( "f(x) = " ));
136
137 bool bHaveSlope = false;
138
139 if( m_fSlope != 0.0 )
140 {
141 if( ::rtl::math::approxEqual( fabs( m_fSlope ), 1.0 ))
142 {
143 if( m_fSlope < 0 )
144 aBuf.append( UC_MINUS_SIGN );
145 }
146 else
147 aBuf.append( getFormattedString( xNumFormatter, nNumberFormatKey, m_fSlope ));
148 aBuf.append( sal_Unicode( 'x' ));
149 bHaveSlope = true;
150 }
151
152 if( bHaveSlope )
153 {
154 if( m_fIntercept < 0.0 )
155 {
156 aBuf.append( UC_SPACE );
157 aBuf.append( UC_MINUS_SIGN );
158 aBuf.append( UC_SPACE );
159 aBuf.append( getFormattedString( xNumFormatter, nNumberFormatKey, fabs( m_fIntercept )));
160 }
161 else if( m_fIntercept > 0.0 )
162 {
163 aBuf.appendAscii( RTL_CONSTASCII_STRINGPARAM( " + " ));
164 aBuf.append( getFormattedString( xNumFormatter, nNumberFormatKey, m_fIntercept ));
165 }
166 }
167 else
168 {
169 aBuf.append( getFormattedString( xNumFormatter, nNumberFormatKey, m_fIntercept ));
170 }
171
172 return aBuf.makeStringAndClear();
173 }
174
175 } // namespace chart
176