quad3d.dem

来自「Delphi Pascal 数据挖掘领域算法包 数值算法大全」· DEM 代码 · 共 52 行

PROGRAM d4r9(input,output);
(* driver for routine QUAD3D *)
CONST
   pi=3.1415926;
   nval=10;
VAR
   i : integer;
   s,xmax,xmin,xmax5 : real;
   glx,gly : real;

FUNCTION func(x,y,z: real): real;
BEGIN
   func := sqr(x)+sqr(y)+sqr(z)
END;

FUNCTION z1(x,y: real): real;
BEGIN
   z1 := -sqrt(sqr(xmax)-sqr(x)-sqr(y))
END;

FUNCTION z2(x,y: real): real;
BEGIN
   z2 := sqrt(sqr(xmax)-sqr(x)-sqr(y))
END;

FUNCTION y1(x: real): real;
BEGIN
   y1 := -sqrt(sqr(xmax)-sqr(x))
END;

FUNCTION y2(x: real): real;
BEGIN
   y2 := sqrt(sqr(xmax)-sqr(x))
END;

(*$I MODFILE.PAS *)

(*$I QUAD3D.PAS *)

BEGIN
   writeln('Integral of r^2 over a spherical volume');
   writeln;
   writeln('radius':13,'QUAD3D':9,'Actual':10);
   FOR i := 1 to nval DO BEGIN
      xmax := 0.1*i;
      xmin := -xmax;
      quad3d(xmin,xmax,s);
      xmax5 := sqr(sqr(xmax))*xmax;
      writeln(xmax:12:2,s:10:4,4.0*pi*(xmax5)/5.0:10:4)
   END
END.