Template polynomial class with unit tests

snippets/CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.13)
 project(snippets)
 
-set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_STANDARD 17)
 
 add_executable(pM pietMondrian.cpp)
 
@@ -29,9 +29,9 @@ else()
     message(FATAL_ERROR "GTest pas trouvé")
 endif()
 
-add_executable(coincheTest gTestCoinche.cpp Coinche.cpp Coinche.h)
 
 if(GTest_FOUND)
+    add_executable(coincheTest gTestCoinche.cpp Coinche.cpp Coinche.h)
     target_link_libraries(coincheTest ${GTEST_BOTH_LIBRARIES})
     target_link_options(coincheTest PRIVATE -pthread)
 endif()
@@ -46,13 +46,24 @@ target_link_libraries(parseXML pugixml)
 target_include_directories(parseXML PRIVATE ${PugiXML_INCLUDE_DIR})
 target_link_directories(parseXML PRIVATE ${PugiXML_INCLUDE_DIR})
 
-add_executable(xmlTest gTestXMLParser.cpp Circle.h xmlParser.h xmlParser.cpp)
-
-target_include_directories(xmlTest PRIVATE ${PugiXML_INCLUDE_DIR})
-target_link_directories(xmlTest PRIVATE ${PugiXML_INCLUDE_DIR})
-target_link_libraries(xmlTest pugixml)
 
 if(GTest_FOUND)
+    add_executable(xmlTest gTestXMLParser.cpp Circle.h xmlParser.h xmlParser.cpp)
+
+    target_include_directories(xmlTest PRIVATE ${PugiXML_INCLUDE_DIR})
+    target_link_directories(xmlTest PRIVATE ${PugiXML_INCLUDE_DIR})
+    target_link_libraries(xmlTest pugixml)
+
     target_link_libraries(xmlTest ${GTEST_BOTH_LIBRARIES})
     target_link_options(xmlTest PRIVATE -pthread)
 endif()
+
+add_library(polynomial SHARED Polynomial.cpp Polynomial.tpp)
+#target_link_libraries(polynomial -static)
+
+if(GTest_FOUND)
+    add_executable(polynomialTest gTestPolynomial.cpp)
+    target_link_libraries(polynomialTest ${GTEST_BOTH_LIBRARIES})
+    target_link_options(polynomialTest PRIVATE -pthread)
+    target_link_libraries(polynomialTest polynomial)
+endif()

snippets/Polynomial.cpp

@@ -0,0 +1,5 @@
+//
+// Created by trotfunky on 09/05/19.
+//
+
+#include "Polynomial.tpp"

snippets/Polynomial.tpp

@@ -0,0 +1,318 @@
+//
+// Created by trotfunky on 09/05/19.
+//
+
+#ifndef SNIPPETS_POLYNOMIAL_TPP
+#define SNIPPETS_POLYNOMIAL_TPP
+
+#include <vector>
+#include <map>
+#include <iostream>
+#include <math.h>
+
+template <typename T> class Polynomial;
+
+/**
+ * Class allowing creation, manipulation and calculation of polynomials
+ * Factors are stored from the lowest power to the highest
+ * The polynomial has at least one factor, which defaults to zero
+ * @tparam T Has to be an arithmetic type (std::is_arithmetic<T>::value is true)
+ */
+template <typename T>
+class Polynomial {
+public:
+    Polynomial();
+    explicit Polynomial(const std::vector<T>&);
+    explicit Polynomial(const std::map<int,T>&);
+
+    template <typename T1>
+    explicit Polynomial(const Polynomial<T1>&);
+
+    int getDegree() const;
+    Polynomial<T> getNthDerivative(int n) const;
+
+    template <typename T1>
+    bool equals(const Polynomial<T1>&) const;
+
+    template <typename T1>
+    auto add(const Polynomial<T1>& operand) const -> Polynomial<decltype(static_cast<T>(0) + operand[0])>;
+
+    template <typename T1>
+    friend std::ostream& operator<<(std::ostream&, const Polynomial<T1>&);
+
+    template<typename T1>
+    T1 operator()(const T1&) const;
+
+    T operator[](int) const;
+
+private:
+    std::vector<T> factors;
+    double factorial(unsigned int n) const;
+
+    template <typename T2>
+    friend class Polynomial;
+};
+
+////////////////////
+///              ///
+/// Definitions  ///
+///              ///
+////////////////////
+
+template<typename T>
+Polynomial<T>::Polynomial()
+{
+    static_assert(std::is_arithmetic<T>::value,"Polynomial must be of an arithmetic type!");
+    factors = {0};
+}
+
+template<typename T>
+Polynomial<T>::Polynomial(const std::vector<T>& polynomialFactors) : Polynomial<T>()
+{
+    if(polynomialFactors.size()>0)
+    {
+        factors = polynomialFactors;
+    }
+}
+
+template<typename T>
+Polynomial<T>::Polynomial(const std::map<int, T>& polynomialFactors) : Polynomial<T>()
+{
+    int degree = polynomialFactors.rbegin()->first;
+    if(degree >= 0)
+    {
+        factors.pop_back();
+    }
+    factors.reserve(degree);
+
+    for(int i = 0;i<=degree;i++)
+    {
+        auto nextFactor = polynomialFactors.find(i);
+        if(nextFactor != polynomialFactors.end())
+        {
+            factors.push_back(nextFactor->second);
+        }
+        else
+        {
+            factors.push_back(0);
+        }
+    }
+}
+
+template <typename T>
+template <typename T1>
+Polynomial<T>::Polynomial(const Polynomial<T1>& copied)
+{
+    static_assert(std::is_arithmetic<T>::value,"Polynomial must be of an arithmetic type!");
+
+    for(const T1& factor : copied.factors)
+    {
+        factors.push_back(static_cast<T>(factor));
+    }
+}
+
+/**
+ * Returns the degree of the polynomial.
+ * @tparam T Type of the polynomial factors
+ * @return Degree of the polynomial, -1 if it is the null-polynomial
+ */
+template<typename T>
+int Polynomial<T>::getDegree() const
+{
+    for(int i = factors.size()-1;i>=0;i--)
+    {
+        if(factors[i] != 0)
+        {
+            return(i);
+        }
+    }
+    return(-1);
+}
+
+/**
+ * Computes the nth derivative of the polynomial
+ * @tparam T Polyniaml factor type
+ * @param  n Order of the derivative
+ * @return Derived polynomial, null-polynomial if the order is greater than the degree
+ */
+template<typename T>
+Polynomial<T> Polynomial<T>::getNthDerivative(int n) const
+{
+    if(n<=0)
+    {
+        return(Polynomial<T>(*this));
+    }
+
+    if(n>getDegree())
+    {
+        return(Polynomial<T>());
+    }
+
+    std::vector<T> newFactors;
+
+    for(int i = n;i<factors.size();i++)
+    {
+        newFactors.push_back(factors[i]*factorial(i)/factorial(i-n));
+    }
+
+    return(Polynomial<T>(newFactors));
+}
+
+template<typename T>
+double Polynomial<T>::factorial(unsigned int n) const
+{
+    double value = 1;
+    for(unsigned int i = 2;i<=n;i++)
+    {
+        value *= i;
+    }
+
+    return(value);
+}
+
+template<typename T>
+template<typename T1>
+bool Polynomial<T>::equals(const Polynomial<T1>& operand) const
+{
+    if(getDegree() != operand.getDegree())
+    {
+        return(false);
+    }
+    if(getDegree() == -1)
+    {
+        return(true);
+    }
+    const std::vector<T1>& p2Factors = operand.factors;
+
+    for(int i = factors.size();i>=0;i--)
+    {
+        if(factors[i] != p2Factors[i])
+        {
+            return(false);
+        }
+    }
+
+    return(true);
+}
+
+template<typename T>
+template<typename T1>
+auto Polynomial<T>::add(const Polynomial<T1>& operand) const -> Polynomial<decltype(static_cast<T>(0) + operand[0])>
+{
+    bool isLargest = true;
+
+    int largestSize = factors.size();
+    int smallestSize = operand.factors.size();
+
+    if(getDegree() < operand.getDegree())
+    {
+        isLargest = false;
+
+        smallestSize = factors.size();
+        largestSize = operand.factors.size();
+    }
+
+    std::vector<decltype(static_cast<T>(0)+operand[0])> resultPolynomial = {};
+    resultPolynomial.reserve(largestSize);
+
+    for(int i = 0;i<smallestSize;i++)
+    {
+        resultPolynomial.push_back(factors[i]+operand[i]);
+    }
+
+    for(int i = smallestSize;i<largestSize;i++)
+    {
+        resultPolynomial.push_back((isLargest ? factors[i] : operand[i]));
+    }
+
+    return Polynomial<decltype(static_cast<T>(0)+operand[0])>(resultPolynomial);
+}
+
+////////////////////
+///              ///
+///   Operators  ///
+///              ///
+////////////////////
+
+template<typename T1,typename T2>
+bool operator==(const Polynomial<T1>& p1, const Polynomial<T2>& p2)
+{
+    return(p1.equals(p2));
+}
+
+
+/**
+ * Computes the sum of the two polynomials by adding factor by factor at first and pushing back
+ * the leftover factors from the largest polynomial if their are different in degree.
+ * @tparam T  Type of the first polynomial
+ * @tparam R  Type of the second polynomial
+ * @param p1  First polynomial
+ * @param p2  Second polynomial
+ * @return    Sum of the two polynomials, null polynomial if both of them are null. The type is deduced from the addition
+ *              of the first factors of the two polynomials.
+ */
+template<typename T1, typename T2>
+auto operator+(const Polynomial<T1>& p1, const Polynomial<T2>& p2) -> Polynomial<decltype(p1[0] + p2[0])>
+{
+    return(p1.add(p2));
+}
+
+template <typename T>
+std::ostream& operator<<(std::ostream& ostream, const Polynomial<T>& polynomial)
+{
+    if(polynomial.getDegree() < 0)
+    {
+        ostream << "0 ";
+        return ostream;
+    }
+
+    const std::vector<T>& factors = polynomial.factors;
+
+    if(factors[0] > 0)
+    {
+        ostream << factors[0] << " ";
+    }
+    else if(factors[0] < 0)
+    {
+        ostream << std::showpos << factors[0] << " ";
+    }
+
+    for(int i = 1;i<factors.size();i++)
+    {
+        if(factors[i] != 0)
+        {
+            ostream << std::showpos << factors[i] << "*X^" << std::noshowpos << i << " ";
+        }
+    }
+
+    return(ostream);
+}
+
+template<typename T>
+template<typename T1>
+T1 Polynomial<T>::operator()(const T1& input) const
+{
+    static_assert(std::is_arithmetic<T1>::value,"Cannot evaluate polynomial at a non arithmetic value !");
+
+    if(getDegree() == -1)
+    {
+        return(0);
+    }
+
+    T1 returnValue = 0;
+    for(int i = 0;i<factors.size();i++)
+    {
+        returnValue += factors[i] * pow(input,i);
+    }
+
+    return(returnValue);
+}
+
+template<typename T>
+T Polynomial<T>::operator[](const int index) const
+{
+    return(factors.at(index));
+}
+
+
+#endif //SNIPPETS_POLYNOMIAL_TPP

snippets/gTestPolynomial.cpp

@@ -0,0 +1,196 @@
+//
+// Created by trotfunky on 09/05/19.
+//
+
+#include <gtest/gtest.h>
+#include "Polynomial.tpp"
+
+class PolynomialOperationTest : public ::testing::Test
+{
+protected:
+    void SetUp() override
+    {
+        pInt = Polynomial<int>({1,2,3});
+        pFloat = Polynomial<float>({-1.0,0,2.0});
+        pLarge = Polynomial<int>({{10,1},{0,5}});
+    }
+
+    Polynomial<int> pInt;
+    Polynomial<float> pFloat;
+    Polynomial<int> pLarge;
+};
+
+TEST(PolynomialTest,polynomialCreation)
+{
+    Polynomial<int> pTestInt = Polynomial<int>({1,2,3});
+    EXPECT_EQ(pTestInt[0],1);
+    EXPECT_EQ(pTestInt[1],2);
+    EXPECT_EQ(pTestInt[2],3);
+    EXPECT_EQ(2,pTestInt.getDegree());
+
+    std::cout << "Int polynomial : " << pTestInt << std::endl;
+
+    Polynomial<float> pTestFloat = Polynomial<float>({0,0,1,0});
+    EXPECT_EQ(pTestFloat[0],0);
+    EXPECT_EQ(pTestFloat[1],0);
+    EXPECT_EQ(pTestFloat[2],1);
+    EXPECT_EQ(pTestFloat[3],0);
+    EXPECT_EQ(2,pTestFloat.getDegree());
+
+    std::cout << "Float polynomial : " << pTestFloat << std::endl;
+
+    Polynomial<float> pTestCopy = Polynomial<float>(pTestInt);
+    EXPECT_EQ(pTestCopy[0],1);
+    EXPECT_EQ(pTestCopy[1],2);
+    EXPECT_EQ(pTestCopy[2],3);
+
+    std::cout << pTestCopy << " is a copy of " << pTestInt << std::endl;
+
+    Polynomial<int> pTestMapInit = Polynomial<int>({{0,1},{2,3},{10,10}});
+    EXPECT_EQ(pTestMapInit[0],1);
+    EXPECT_EQ(pTestMapInit[2],3);
+    EXPECT_EQ(pTestMapInit[10],10);
+
+    std::cout << "Polynomial created via a map : " << pTestMapInit << std::endl;
+
+    std::cout << std::endl;
+}
+
+TEST_F(PolynomialOperationTest,polynomialSum)
+{
+    Polynomial<int> summedIntP = pInt + pInt;
+    EXPECT_EQ(summedIntP[0],2);
+    EXPECT_EQ(summedIntP[1],4);
+    EXPECT_EQ(summedIntP[2],6);
+
+    std::cout << "Summed int polynomial : " << summedIntP << std::endl;
+
+    Polynomial<float> summedFloatP = pFloat + pFloat;
+    EXPECT_EQ(summedFloatP[0],-2.0f);
+    EXPECT_EQ(summedFloatP[1],0);
+    EXPECT_EQ(summedFloatP[2],4.0f);
+
+    std::cout << "Summed float polynomial : " << summedFloatP << std::endl;
+
+    auto summedAuto = pInt + pFloat;
+    EXPECT_EQ(summedAuto[0],0);
+    EXPECT_EQ(summedAuto[1],2);
+    EXPECT_EQ(summedAuto[2],5);
+
+    summedAuto = pFloat + pInt;
+    EXPECT_EQ(summedAuto[0],0);
+    EXPECT_EQ(summedAuto[1],2);
+    EXPECT_EQ(summedAuto[2],5);
+
+    std::cout << "Summed auto polynomial : " << summedAuto << std::endl;
+
+    Polynomial<int> summedLarge = pInt + pLarge;
+    EXPECT_EQ(summedLarge[0],6);
+    EXPECT_EQ(summedLarge[1],2);
+    EXPECT_EQ(summedLarge[2],3);
+    for(int i = 3;i<10;i++)
+        EXPECT_EQ(summedLarge[i],0);
+    EXPECT_EQ(summedLarge[10],1);
+
+    std::cout << "Summed small and large polynomials : " << summedLarge << std::endl;
+
+    std::cout << std::endl;
+}
+
+TEST_F(PolynomialOperationTest,polynomialComparison)
+{
+    EXPECT_TRUE(Polynomial<int>() == Polynomial<int>());
+    EXPECT_TRUE(Polynomial<float>() == Polynomial<int>());
+
+    Polynomial<int> pCompInt = Polynomial<int>({1,2,3});
+    EXPECT_TRUE(pCompInt == pInt);
+    EXPECT_TRUE(pInt == pCompInt);
+
+    Polynomial<float> pCompFloat = Polynomial<float>({-1.0,0,2.0});
+    EXPECT_TRUE(pCompFloat == pFloat);
+    EXPECT_TRUE(pFloat == pCompFloat);
+
+    EXPECT_TRUE(Polynomial<float>(pFloat) == pFloat);
+    EXPECT_TRUE(Polynomial<float>(pInt) == pInt);
+
+    EXPECT_FALSE(pInt == pFloat);
+    EXPECT_FALSE(pInt == Polynomial<int>());
+    EXPECT_FALSE(pInt == Polynomial<float>());
+
+    std::cout << std::endl;
+}
+
+TEST_F(PolynomialOperationTest,polynomialDerivation)
+{
+    EXPECT_TRUE(pInt.getNthDerivative(0) == pInt);
+    EXPECT_TRUE(pFloat.getNthDerivative(0) == pFloat);
+
+    std::cout << "Testing with Polynomial<int> ..." << std::endl;
+
+    Polynomial<int> expectedIntDerivative = Polynomial<int>(std::vector<int>({2,6}));
+    EXPECT_TRUE(expectedIntDerivative == pInt.getNthDerivative(1));
+
+    std::cout << "First order derivative : " << pInt.getNthDerivative(1) << std::endl;
+
+    expectedIntDerivative = Polynomial<int>({6});
+    EXPECT_TRUE(expectedIntDerivative == pInt.getNthDerivative(2));
+
+    std::cout << "Second order derivative : " << pInt.getNthDerivative(2) << std::endl;
+
+    expectedIntDerivative = Polynomial<int>();
+    EXPECT_TRUE(expectedIntDerivative == pInt.getNthDerivative(3));
+    EXPECT_TRUE(expectedIntDerivative == pInt.getNthDerivative(10));
+
+    std::cout << "Third order derivative : " << pInt.getNthDerivative(3) << std::endl;
+    std::cout << "Tenth order derivative : " << pInt.getNthDerivative(10) << std::endl;
+
+
+    std::cout << std::endl;
+    std::cout << "Testing with Polynomial<float> ..." << std::endl;
+
+    Polynomial<float> expectedFloatDerivative = Polynomial<float>(std::vector<float>({0,4}));
+    EXPECT_TRUE(expectedFloatDerivative == pFloat.getNthDerivative(1));
+
+    std::cout << "First order derivative : " << pFloat.getNthDerivative(1) << std::endl;
+
+    expectedFloatDerivative = Polynomial<float>({4});
+    EXPECT_TRUE(expectedFloatDerivative == pFloat.getNthDerivative(2));
+
+    std::cout << "Second order derivative : " << pFloat.getNthDerivative(2) << std::endl;
+
+    expectedFloatDerivative = Polynomial<float>();
+    EXPECT_TRUE(expectedFloatDerivative == pFloat.getNthDerivative(3));
+    EXPECT_TRUE(expectedFloatDerivative == pFloat.getNthDerivative(10));
+
+    std::cout << "Third order derivative : " << pFloat.getNthDerivative(3) << std::endl;
+    std::cout << "Tenth order derivative : " << pFloat.getNthDerivative(10) << std::endl;
+
+    std::cout << std::endl;
+}
+
+TEST_F(PolynomialOperationTest,polynomialAssertion)
+{
+    EXPECT_EQ(pInt(0),1);
+    EXPECT_EQ(pInt(0.0f),1);
+    EXPECT_EQ(pInt(1),6);
+    EXPECT_EQ(pInt(1.0),6);
+    EXPECT_EQ(pInt(-1),2);
+
+    EXPECT_EQ(pFloat(0),-1);
+    EXPECT_EQ(pFloat(0.0),-1);
+    EXPECT_EQ(pFloat(1),1);
+    EXPECT_EQ(pFloat(-1),1);
+
+    EXPECT_EQ(pLarge(0),5);
+    EXPECT_EQ(pLarge(1),6);
+    EXPECT_EQ(pLarge(2),1029);
+
+    EXPECT_EQ(Polynomial<bool>()(100),0);
+    EXPECT_EQ(Polynomial<bool>()(0),0);
+}
+
+int main(int argc, char** argv)
+{
+    ::testing::InitGoogleTest(&argc,argv);
+    return RUN_ALL_TESTS();
+}