polyfitdemo.cpp

多项式曲线拟合 任意介数 Purpose - Least-squares curve fit of arbitrary order working in C++ Builder 2007 as

//---------------------------------------------------------------------------

#pragma hdrstop



#include "CPolyfit.cpp"
#include "polyfitdemo.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)

#pragma link "cspin"

#pragma resource "*.dfm"

TForm1 *Form1;
using namespace std; //std::vector;



//---------------------------------------------------------------------------



bool __fastcall CData::ReadData()
/*
=============================================================================
  ReadData function reads the data from an existing text file. Save the x, y
  values to the vectors X and Y.

  Return:
	true               when success
	false              when fails
=============================================================================
*/
{
 if(Owner->OpenDialog1->Execute())
 {
  X.clear();
  Y.clear();
  A.clear();
  ifstream In(Owner->OpenDialog1->FileName.c_str());
  double x, y;
  while(In)
  {
   In >> x;
   In >> y;
   X.push_back(x);
   Y.push_back(y);
  }
  In.close();

  return true;
 }
 return false;
}
//-----------------------------------------------------------------------------


double __fastcall CData::F(double x)
{
 int n = A.size();
 double ret = 0;
 for(int i = 0; i < n; ++i)
 {
  if(x == 0)
   ret += A[i];
  else
   ret += A[i] * NSUtility::Pow(x, i);
 }
 return ret;
}
//---------------------------------------------------------------------------
double __fastcall CData::RootMeanSquare(vector<long double> &x, vector<long double> &y)
{
 double ret = 0;
 double t;
 unsigned int n = x.size();
 for(unsigned int i = 0; i < n; ++i)
 {
  t = y[i] - F(x[i]);
  ret += t * t;
 }
 return sqrt(ret) / n;
}
//----------------------------------------------------------------------------


//---------------------------------------------------------------------------

void __fastcall CData::RemoveSignificant(vector<long double> &x, vector<long double> &y, double rms)
{

 // remove elements where y[i] - f(x[i]) > 1.0
 for(unsigned int i = 0; i < N; ++i)
 {
  if(fabs(y[i] - F(x[i])) > 10 * rms)
  {
   x[i] = -100.0;
   y[i] = -100.0;
  }
 }
 // remove all -100, s
 x.erase(remove(x.begin(), x.end(), -100.0), x.end());
 y.erase(remove(y.begin(), y.end(), -100.0), y.end());
}
//----------------------------------------------------------------------------


//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
 : TForm(Owner)
{
 Data = new CData(this);
}
//---------------------------------------------------------------------------

__fastcall TForm1::~TForm1()
{

 delete Data;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::btnReadClick(TObject *Sender)
{
 Data->ReadData();

}
//---------------------------------------------------------------------------

void __fastcall TForm1::btnCalcClick(TObject *Sender)
{
 TCursor oldcursor = Screen->Cursor;
 Screen->Cursor = crHourGlass;

 try
 {
  int nOrder = CSpinEdit1->Value;
  double correl;

  CPolyFit<long double> *PolyFitObj = new CPolyFit<long double>();

  Data->A.clear();
  for(int i = 0; i < nOrder; ++i)
   Data->A.push_back(0.0);
  correl = PolyFitObj->PolyFit (Data->X, Data->Y, Data->A);
  ListBox1->Items->Add(AnsiString("Corr Coefficient =  ") + correl);
  ListBox1->Items->Add("");
  for(size_t i = 0; i < Data->A.size(); ++i)
  {
   AnsiString spaces("");
   if(i < 100)
    spaces += ' ';
   if(i < 10)
    spaces += ' ';
   ListBox1->Items->Add(AnsiString('A') + i + spaces + " =      " + float(Data->A[i]));
  }
  ListBox1->Items->Add("");
  

  ListBox1->Items->Add("=========================================================");
//  Data->DrawLine(clRed);
  delete PolyFitObj;
 }
 __finally
 {
  Screen->Cursor = oldcursor;

 }
}
//---------------------------------------------------------------------------