Question

我正在学习线性代数，并且认为我将一些新发现的知识转换为一个小型的C ++程序。对于这些数字，我偶然发现CLN, a Class Library for Numbers，我正在尝试使用它。

LinearEquation.h：

#include <iostream>
#include <cln/real.h>
#include <cln/rational.h>
using namespace std;
using namespace cln;

class LinearEquation{
public:
  // constructor
  LinearEquation(cl_R* coefficients, int numFactors, cl_R constant);

  // copy constructor
  LinearEquation(const LinearEquation& le);

  // assignment constructor
  LinearEquation& operator=(const LinearEquation& rhs);

  // destructor
  ~LinearEquation();

  /*
    isSolution returns true if a provided set of rational numbers is a solution
    to this linear Equation, and false otherwise.

    No error checking is done, thus s and num is expected to match the number 
    of items in _coefficients;
  */
  bool isSolution(const cl_R* s, int num);

private:
  int _numFactors;
  cl_R* _coefficients;
  cl_R _constant;
};

LinearEquation.cpp：

#include "LinearEquation.h"

// constructor
LinearEquation::LinearEquation(cl_R* coefficients,
                   int numFactors,
                   cl_R constant){
  _numFactors = numFactors;
  _coefficients = new cl_R[numFactors];
  for(int i=0; i<numFactors; i++){
    _coefficients[i] = coefficients[i];
  }
  _constant = constant;
}

// copy constructor
LinearEquation::LinearEquation(const LinearEquation& obj){
  _numFactors = obj._numFactors;
  _coefficients = new cl_R[_numFactors];
  for(int i=0; i<_numFactors; i++){
    _coefficients[i] = obj._coefficients[i];
  }
  _constant = obj._constant;
}

// assignment constructor
LinearEquation& LinearEquation::operator=(const LinearEquation& le){
  if(this != &le){
    _numFactors = le._numFactors;
    delete [] _coefficients;
    _coefficients = new cl_R[_numFactors];
    for(int i=0; i<_numFactors; i++){
      _coefficients[i] = le._coefficients[i];
    }
    _constant = le._constant;
  }
}

// destructor
LinearEquation::~LinearEquation(){
  delete [] _coefficients;
}

bool LinearEquation::isSolution(const cl_R* s, int num){
  cl_R sum = 0;
  for(int i=0; i<_numFactors; i++){
    sum = sum + (_coefficients[i] * s[i]);
  }
  return sum == _constant;
}

最后，main.cpp

#include <cln/integer.h>
#include <cln/real.h>
#include "LinearEquation.h"
#include <iostream>
using namespace cln;
using namespace std;

int main(){
  int le1NumFactors = 2;
  cl_R* le1Coefficients = new cl_R[le1NumFactors];
  le1Coefficients[0] = 3;
  le1Coefficients[1] = 2;
  cl_R le1Constant = 7;
  LinearEquation le1(le1Coefficients, le1NumFactors, le1Constant);

  int le2NumFactors = 2;
  cl_R* le2Coefficients = new cl_R[le2NumFactors];
  le2Coefficients[0] = -1;
  le2Coefficients[1] = 1;
  cl_R le2Constant = 6;
  LinearEquation le2(le2Coefficients, le2NumFactors, le2Constant);

  cl_R* solution = new cl_R[le2NumFactors];
  solution[0] = -1;
  solution[1] = 5;

  cout << "(-1, 5) is " << (le1.isSolution(solution, 2) ? "" : "not ")
       << "a solution to le1." << endl;
  cout << "(-1, 5) is " << (le2.isSolution(solution, 2) ? "" : "not ")
       << "a solution to le2." << endl;

  delete [] le1Coefficients;
  delete [] le2Coefficients;
  delete [] solution;

  return 0;
}

g ++ LinearEquation.h LinearEquation.cpp -c

工作正常，但

g ++ main.cpp LinearEquation.o

没有。生成以下错误消息：

lowerkey @ cassiopeia：〜/ Desktop / math $ g ++ main.cpp LinearEquation.o /tmp/ccMceM9l.o：在功能上 __static_initialization_and_destruction_0(int, int)': main.cpp:(.text+0x4ab): undefined reference to CLN :: cl_random_def_init_helper :: cl_random_def_init_helper（）” main.cpp :(。text + 0x4b0）：未定义引用 cln::cl_random_def_init_helper::~cl_random_def_init_helper()' main.cpp:(.text+0x4e0): undefined reference to CLN :: cl_FF_globals_init_helper :: cl_FF_globals_init_helper（）” main.cpp :(。text + 0x4e5）：未定义的引用 cln::cl_FF_globals_init_helper::~cl_FF_globals_init_helper()' main.cpp:(.text+0x509): undefined reference to CLN :: cl_DF_globals_init_helper :: cl_DF_globals_init_helper（）” main.cpp :(。text + 0x50e）：未定义引用 cln::cl_DF_globals_init_helper::~cl_DF_globals_init_helper()' main.cpp:(.text+0x532): undefined reference to CLN :: cl_LF_globals_init_helper :: cl_LF_globals_init_helper（）” main.cpp :(。text + 0x537）：未定义引用 cln::cl_LF_globals_init_helper::~cl_LF_globals_init_helper()' /tmp/ccMceM9l.o: In function CLN :: cl_gc_dec_pointer_refcount（CLN :: cl_heap *）'： main.cpp中:( text._ZN3cln26cl_gc_dec_pointer_refcountEPNS_7cl_heapE [CLN :: cl_gc_dec_pointer_refcount（CLN :: cl_heap *）] + 0×28）：对cln::cl_free_heap_object(cln::cl_heap*)' /tmp/ccMceM9l.o: In function cln :: cl_I_classes_dummy :: cl_I_classes_dummy（）'的未定义引用：。main.cpp中:( text._ZN3cln18cl_I_classes_dummyC1Ev [CLN :: cl_I_classes_dummy :: cl_I_classes_dummy（）] + 0x9）：未定义引用cln::cl_class_fixnum' LinearEquation.o: In function LinearEquation :: isSolution（cln :: cl_R const *，int）'： LinearEquation.cpp :(。text + 0x61a）：未定义的引用 cln::operator*(cln::cl_R const&, cln::cl_R const&)' LinearEquation.cpp:(.text+0x636): undefined reference to cln :: operator +（cln :: cl_R const＆amp;，cln :: cl_R const＆amp;）'LinearEquation.o：在函数__static_initialization_and_destruction_0(int, int)': LinearEquation.cpp:(.text+0x741): undefined reference to中cln :: cl_random_def_init_helper :: cl_random_def_init_helper（）' LinearEquation.cpp :(。text + 0x746）：未定义的引用 cln::cl_random_def_init_helper::~cl_random_def_init_helper()' LinearEquation.cpp:(.text+0x76a): undefined reference to CLN :: cl_FF_globals_init_helper :: cl_FF_globals_init_helper（）” LinearEquation.cpp :(。text + 0x76f）：未定义的引用 cln::cl_FF_globals_init_helper::~cl_FF_globals_init_helper()' LinearEquation.cpp:(.text+0x793): undefined reference to CLN :: cl_DF_globals_init_helper :: cl_DF_globals_init_helper（）” LinearEquation.cpp :(。text + 0x798）：未定义的引用 cln::cl_DF_globals_init_helper::~cl_DF_globals_init_helper()' LinearEquation.cpp:(.text+0x7bc): undefined reference to CLN :: cl_LF_globals_init_helper :: cl_LF_globals_init_helper（）” LinearEquation.cpp :(。text + 0x7c1）：未定义的引用 cln::cl_LF_globals_init_helper::~cl_LF_globals_init_helper()' LinearEquation.o: In function cln :: operator ==（cln :: cl_R const＆amp ;,, cln :: cl_R const＆amp;）'： LinearEquation.cpp :(。text._ZN3clneqERKNS_4cl_RES2_ [CLN :: ==操作符（CLN :: cl_R const＆amp;，cln :: cl_R const＆amp;）] + 0x14）：未定义的引用 `cln :: equal（cln :: cl_R const＆amp;，cln :: cl_R const＆amp;）'collect2：ld返回 1退出状态

Answer 1

看起来你没有链接cln库。尝试以下（假设库已正确安装）：

g++ main.cpp LinearEquation.o -lcln

有关编译的更多详细信息，请参阅文档： http://www.ginac.de/CLN/cln_11.html#SEC64

如何编译以下程序？

1 个答案: