Fungsi Pembangkit Variabel Random

Fungsi Distribusi Uniform
Function Uniform (a,b : double) : double;
Var u : double;
Begin
u := random;
Uniform := (b-a) * u + a;
End;

Fungsi Distribusi Eksponensial
Function Eksponensial (beta : double) : double;
Var u : double;
Begin
u := random;
Eksponensial := -beta * ln(u);
End;

Fungsi Distribusi Normal
Procedure Normal (mean,variance : double ; Var z1,z2 : double);
Var u1,u2,v1,v2,w,y,x1,x2 : double;
Begin
Repeat
u1 := random;
u2 := random;
v1 := 2 * u1 – 1;
v2 := 2 * u2 – 1;
w := sqr(v1) + sqr(v2);
if w <= 1 then
begin
y := sqrt ((-2*ln(w))/w);
x1 := v1 * y;
x2 := v2 * y;
z1 := sqrt (variance) * x1 + mean;
z2 := sqrt (variance) * x2 + mean;
end
Until w <= 1;
End;
Procedure Distribusi Lognormal procedure lognormal (mean,varr : double; Var zln1,zln2 : double);
Var y1, y2 : double;
begin
Normal (mean,varr,y1,y2);
zln1 := exp(y1);
zln2 := exp(y2);
end;
Fungsi Distribusi Weibull Function Weibull (alfa,beta: double) : double;
Var u,z : double;
Begin u := random;
z := -ln(u);
Weibull := beta * exp (ln(z)/alfa);
End;
Fungsi Distribusi t-student function tdistribution(m:integer):double;
Label r2;
Var v,x,r,s,c,a,f,g,mm : real;
begin mm:=0;
if m < 1 then begin writeln('impermissible degrees of freedom.'); halt;
end;
if (m mm) then begin s:=m; c:=-0.25*(s+1);
a:=4/power((1+1/s),c);
f:=16/a;
if m>1 then
begin
g:=s-1;
g:=power(((s+1)/g),c)*sqrt((s+s)/g);
end else
g := 1;
mm:=m;
end;
r2:repeat
r:=random;
until r > 0.0;
x:=(2*random-1)*g/r;
v:=x*x;
if (v>(5-a*r)) then
begin
if ((m>=3) and (r*(v+3)>f)) then goto r2;
if (r>power((1+v/s),c)) then goto r2;
end;
tdistribution :=x;
end;
begin
tipe11[1]:=0.2;
tipe11[1]:=0.3;
tipe11[1]:=0.5;
tipe11[1]:=0.8;
tipe11[1]:=1.0;
end.