sw/src/pascal/INTEGR.V3

   1 PROGRAM INTEGRATION(INPUT,OUTPUT);
   2
   3     VAR ANFANG,ENDE,FLAECHE: REAL;
   4
   5
   6 (************* HIER INTEGRAND DEFINIEREN **************)
   7     FUNCTION F(X: REAL): REAL;
   8         BEGIN
   9             F := SIN(X)
  10         END;
  11 (******************************************************)
  12
  13
  14
  15     FUNCTION INTEGRAL(A,B: REAL): REAL;
  16
  17         CONST   X1=0.148874338982;      C1=0.295524224715;
  18                 X2=0.433395394129;      C2=0.269266719310;
  19                 X3=0.679409568299;      C3=0.219086362516;
  20                 X4=0.865063366689;      C4=0.149451349151;
  21                 X5=0.973906528517;      C5=0.066671344309;
  22
  23         VAR     DX, XM: REAL;
  24
  25     BEGIN
  26         DX := (B-A)/2;
  27         XM := (A+B)/2;
  28         INTEGRAL := (   C1*( F(XM+X1*DX) + F(XM-X1*DX) ) +
  29                         C2*( F(XM+X2*DX) + F(XM-X2*DX) ) +
  30                         C3*( F(XM+X3*DX) + F(XM-X3*DX) ) +
  31                         C4*( F(XM+X4*DX) + F(XM-X4*DX) ) +
  32                         C5*( F(XM+X5*DX) + F(XM-X5*DX) ) ) * DX
  33     END (* INTEGRAL *);
  34
  35
  36 BEGIN
  37     WRITELN("B E S T I M M T E S   I N T E G R A L");
  38     WRITELN;
  39     WRITE("INTERVALLGRENZEN");  READ(ANFANG,ENDE);
  40     FLAECHE := INTEGRAL(ANFANG,ENDE);
  41     WRITELN;
  42     WRITELN("WERT DES INTEGRALS: ", FLAECHE :18:10)
  43 END.