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

#include <vcl.h>
#include <math.h>
#pragma hdrstop

#include "Unit4.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}

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

int factorial(int x)
{
        return !x ? 1 : x * factorial(x - 1);
}

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

void __fastcall TForm1::SG1DrawCell(TObject *Sender, int ACol,
      int ARow, TRect &Rect, TGridDrawState State)
{
        int x,y;
        y = Rect.top + (Rect.Height() - SG1->Canvas->TextHeight(SG1->Cells[ACol][ARow])) / 2;
        if (ARow == 0) {
                x = Rect.left + (Rect.Width() - SG1->Canvas->TextWidth(SG1->Cells[ACol][ARow])) / 2;
                SG1->Canvas->Brush->Color = clBtnFace;
                SG1->Canvas->Font->Color = clBlack;
                SG1->Canvas->FillRect(Rect);
                SG1->Canvas->TextOut(x, y, SG1->Cells[ACol][ARow]);
        }
}
//---------------------------------------------------------------------------

void __fastcall TForm1::FormCreate(TObject *Sender)
{
        SG1->Cells[0][0] = "x";
        SG1->Cells[1][0] = "Y(x)";
        SG1->Cells[2][0] = "S(x)";
        SG1->Cells[3][0] = "|Y(x)-S(x)|";
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Button1Click(TObject *Sender)
{
        double a = StrToFloat(Edit1->Text), b = StrToFloat(Edit2->Text), h = StrToFloat(Edit3->Text), n = StrToFloat(Edit4->Text);
        Labout (a, b, h, n, RG1->ItemIndex);
}
//---------------------------------------------------------------------------

void __fastcall TForm1::Labout(double a, double b, double h, double n, int f)
{
        double y, s;
        Label1->Caption = "ﾈ荳・糺褊韃";
        switch (f){
                  case 1: for (int i = 1; a <= b+h/2; a+=h, i++) {
                                  SG1->Cells[0][i] = FloatToStrF(a, ffGeneral, 5, 5);
                                  y = (pow(a, 2)/4 + a/2 + 1)*exp(a/2);
                                  SG1->Cells[1][i] = FloatToStrF(y, ffFixed, 5, 5);
                                  SG1->RowCount++;
                          } ;
                          break;
                  case 2:  for (int i = 1; a <= b+h/2; a+=h, i++) {
                                  SG1->Cells[0][i] = FloatToStrF(a, ffGeneral, 5, 5);
                                  s = 0;
                                  for (int k = 0; k <= n; k++)
                                          s += double(k*k + 1.) / factorial(k) * pow(a/2, k);
                                  SG1->Cells[2][i] = FloatToStrF(s, ffFixed, 5, 5);
                                  SG1->RowCount++;
                          };
                          break;
                  case 3: for (int i = 1; a <= b+h/2; a+=h, i++) {
                                  SG1->Cells[0][i] = FloatToStrF(a, ffGeneral, 5, 5);
                                  y = (pow(a, 2)/4 + a/2 + 1)*exp(a/2);
                                  s = 0;
                                  for (int k = 0; k <= n; k++)
                                          s += double(k*k + 1.) / factorial(k) * pow(a/2, k);
                                  SG1->Cells[3][i] = FloatToStrF(fabs(y - s), ffFixed, 10, 10);
                                  SG1->RowCount++;
                          };
                          break;
                  }
        Label1->Caption = "ﾂ飼頌・湜・鈞粢褊・;
}

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