📄 unit2.pas
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unit Unit2;
interface
uses
unit1;
Function GOLDEN(AX, BX, CX, TOL:real;var XMIN:real):real;
Function BESSJ0(X:real):real;
Function BESSJ1(X:real):real;
Procedure MNBRAK(var AX, BX, CX, FA, FB, FC:real);
implementation
Function GOLDEN(AX, BX, CX, TOL:real;var XMIN:real):real;
const
R = 0.61803399; C = 0.38196601;
Var
X0,X3,X1,X2,F0,F1,F2,F3:real;
begin
X0:=AX;
X3:=CX;
If Abs(CX - BX) > Abs(BX - AX) Then
Begin
X1:=BX;
X2:=BX + C * (CX - BX);
end
Else
begin
X2:=BX;
X1:=BX - C * (BX - AX);
end;
F1:=FUNC(X1);
F2:=FUNC(X2);
While Abs(X3 - X0) > TOL * (Abs(X1) + Abs(X2)) do
begin
If F2 < F1 Then
begin
X0:=X1;
X1:=X2;
X2:=R * X1 + C * X3;
F0:=F1;
F1:=F2;
F2:=FUNC(X2);
end
Else
begin
X3:=X2;
X2:=X1;
X1:=R * X2 + C * X0;
F3:=F2;
F2:=F1;
F1:=FUNC(X1);
end;
end;
If F1 < F2 Then
begin
GOLDEN:=F1;
XMIN:=X1;
end
Else
begin
GOLDEN:=F2;
XMIN:=X2;
end;
end;
Function BESSJ0(X:real):real;
var
AAA,BBB,CCC,Y,AX,Z,DDD,EEE,XX:real;
const
P1=1; P2=-0.001098628627;
P3=0.2734510407e-4; P4=-0.2073370639e-5;
P5=2.093887211E-07;
Q1=-0.1562499995e-1; Q2=0.1430488765e-3;
Q3=-0.6911147651e-5; Q4=7.621095161E-07;
Q5=-9.34945152E-08;
R1=57568490574; R2=-13362590354;
R3=651619640.7; R4=-11214424.18;
R5=77392.33017; R6=-184.9052456;
S1=57568490411; S2=1029532985;
S3=9494680.718; S4=59272.64853;
S5=267.8532712; S6=1;
begin
If Abs(X) < 8 Then
begin
Y:=X * X;
BBB:=Y* (R4+ Y* (R5+ Y* R6));
AAA:=R1+ Y* (R2+ Y* (R3+ BBB));
CCC:=Y* (S3+ Y* (S4+ Y* (S5+ Y* S6)));
BESSJ0:= AAA / (S1+ Y* (S2+ CCC));
end
Else
begin
AX:=Abs(X);
Z:=8/ AX;
Y:=Z* Z;
XX:= AX- 0.785398164;
CCC:=Y* (P3+ Y* (P4+ Y* P5));
AAA:=P1+ Y* (P2+ CCC);
DDD:=Y* (Q3+ Y* (Q4+ Y* Q5));
EEE:=Z* Sin(XX) * (Q1+ Y* (Q2+ DDD));
BESSJ0:= Sqrt(0.636619772 / AX) * (Cos(XX) * AAA- EEE);
End;
End;
Function BESSJ1(X:real):real;
VAR
AAA,BBB,CCC,AX,Z,Y,XX,SGN:real;
const
R1 = 72362614232; R2 = -7895059235;
R3 = 242396853.1; R4 = -2972611.439;
R5 = 15704.4826; R6 = -30.16036606;
S1 = 144725228442; S2 = 2300535178;
S3 = 18583304.74; S4 = 99447.43394;
S5 = 376.9991397; S6 = 1;
P1 = 1; P2 = 0.00183105;
P3 = -0.3516396496e-4; P4 = 0.000002457520174;
P5 = -0.240337019e-6;
Q1 = 0.04687499995; Q2 = -0.2002690873e-3;
Q3 = 0.8449199096e-5; Q4 = -0.88228987e-6;
Q5 = 0.105787412e-6;
begin
If Abs(X) < 8 Then
begin
Y:=X * X;
AAA:=R1 + Y * (R2 + Y * (R3 + Y * (R4 + Y * (R5 + Y * R6))));
BBB:=S1 + Y * (S2 + Y * (S3 + Y * (S4 + Y * (S5 + Y * S6))));
BESSJ1:=X * AAA / BBB;
end
Else
begin
AX:=Abs(X);
Z:=8 / AX;
Y:=Z * Z;
XX:=AX - 2.356194491;
AAA:=P1 + Y * (P2 + Y * (P3 + Y * (P4 + Y * P5)));
BBB:=Q1 + Y * (Q2 + Y * (Q3 + Y * (Q4 + Y * Q5)));
CCC:=Sqrt(0.636619772 / AX);
if X > 0 THEN
SGN:= 1
ELSE
SGN:= -1;
BESSJ1:=CCC * (Cos(XX) * AAA - Z * Sin(XX) * BBB * Sgn);
End;
End;
Procedure MNBRAK(var AX, BX, CX, FA, FB, FC:real);
const
GOLD = 1.618034; GLIMIT = 100; TINY = 1E-20;
var
DUM,R,Q,U,ULIM,FU:real; DONE:boolean;
begin
FA:=FUNC(AX);
FB:=FUNC(BX);
If FB > FA Then
begin
DUM:=AX;
AX:=BX;
BX:=DUM;
DUM:=FB;
FB:=FA;
FA:=DUM;
end;
CX:=BX + GOLD * (BX - AX);
FC:=FUNC(CX);
repeat
If FB < FC Then break;
DONE:=true;
R:=(BX - AX) * (FB - FC);
Q:=(BX - CX) * (FB - FA);
DUM:=Q - R;
If Abs(DUM) < TINY Then DUM:=TINY;
U:=BX - ((BX - CX) * Q - (BX - AX) * R) / (2 * DUM);
ULIM:=BX + GLIMIT * (CX - BX);
If (BX - U) * (U - CX) > 0 Then
begin
FU:=FUNC(U);
If FU < FC Then
begin
AX:=BX;
FA:=FB;
BX:=U;
FB:=FU;
Exit;
end
Else If FU > FB Then
begin
CX:=U;
FC:=FU;
Exit;
end;
U:=CX + GOLD * (CX - BX);
FU:=FUNC(U);
end
Else If (CX - U) * (U - ULIM) > 0 Then
begin
FU:=FUNC(U);
If FU < FC Then
begin
BX:=CX;
CX:=U;
U:=CX + GOLD * (CX - BX);
FB:=FC;
FC:=FU;
FU:=FUNC(U);
end;
end
Else If (U - ULIM) * (ULIM - CX) >= 0 Then
begin
U:=ULIM;
FU:=FUNC(U);
end
Else
begin
U:=CX + GOLD * (CX - BX);
FU:=FUNC(U);
end;
If DONE Then
begin
AX:=BX;
BX:=CX;
CX:=U;
FA:=FB;
FB:=FC;
FC:=FU;
end
Else
DONE:=false;
until not DONE
end;
end.
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