unit2.pas

来自「《Delphi常用数值算法集》的配书源码」· PAS 代码 · 共 30 行

unit Unit2;

interface
uses
    unit1;
procedure QGAUS(A, B:real;var SS:real);
implementation
procedure QGAUS(A, B:real;var SS:real);
var
    X, W:array[0..5] of real;
    XM,XR,DX:real;  J:integer;
begin
    X[1]:=0.1488743389;    X[2]:=0.4333953941;
    X[3]:=0.6794095682;    X[4]:=0.8650633666;
    X[5]:=0.9739065285;
    W[1]:=0.2955242247;    W[2]:=0.2692667193;
    W[3]:=0.2190863625;    W[4]:=0.1494513491;
    W[5]:=0.0666713443;
    XM:=0.5 * (A + B);
    XR:=0.5 * (B - A);
    SS:=0;
    For J:=1 To 5 do
    begin
        DX:=XR * X[J];
        SS:=SS + W[J] * (FUNC(XM + DX) + FUNC(XM - DX));
    end;
    SS:=XR * SS;
end;
end.