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Diffstat (limited to 'plugins/ImportTXT/kol/kolmath.pas')
-rw-r--r-- | plugins/ImportTXT/kol/kolmath.pas | 1845 |
1 files changed, 0 insertions, 1845 deletions
diff --git a/plugins/ImportTXT/kol/kolmath.pas b/plugins/ImportTXT/kol/kolmath.pas deleted file mode 100644 index 9e06418343..0000000000 --- a/plugins/ImportTXT/kol/kolmath.pas +++ /dev/null @@ -1,1845 +0,0 @@ -{=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
-
- KKKKK KKKKK OOOOOOOOO LLLLL
- KKKKK KKKKK OOOOOOOOOOOOO LLLLL
- KKKKK KKKKK OOOOO OOOOO LLLLL
- KKKKK KKKKK OOOOO OOOOO LLLLL
- KKKKKKKKKK OOOOO OOOOO LLLLL
- KKKKK KKKKK OOOOO OOOOO LLLLL
- KKKKK KKKKK OOOOO OOOOO LLLLL
- KKKKK KKKKK OOOOOOOOOOOOO LLLLLLLLLLLLL
- KKKKK KKKKK OOOOOOOOO LLLLLLLLLLLLL
-
- Key Objects Library (C) 2000 by Kladov Vladimir.
-
- mailto: vk@kolmck.net
- Home: http://kolmck.net
-
- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-}
-{
- This code is grabbed from standard math.pas unit,
- provided by Borland Delphi. This unit is for working with
- engineering (mathematical) functions. The main difference
- is that err unit specially designed to handle exceptions
- for KOL is used instead of SysUtils. This allows to make
- size of the executable smaller for about 5K. though this
- value is insignificant for project made with VCL, it can
- be more than 15% of executable file size made with KOL.
-}
-
-{*******************************************************}
-{ }
-{ Borland Delphi Runtime Library }
-{ Math Unit }
-{ }
-{ Copyright (C) 1996,99 Inprise Corporation }
-{ }
-{*******************************************************}
-
-unit kolmath;
-
-{ This unit contains high-performance arithmetic, trigonometric, logorithmic,
- statistical and financial calculation routines which supplement the math
- routines that are part of the Delphi language or System unit. }
-
-{$N+,S-}
-
-{$I KOLDEF.INC}
-
-interface
-
-uses {$IFNDEF MATH_NOERR} err, {$ENDIF} kol;
-
-const { Ranges of the IEEE floating point types, including denormals }
- MinSingle = 1.5e-45;
- MaxSingle = 3.4e+38;
- MinDouble = 5.0e-324;
- MaxDouble = 1.7e+308;
- MinExtended = 3.4e-4932;
- MaxExtended = 1.1e+4932;
- MinComp = -9.223372036854775807e+18;
- MaxComp = 9.223372036854775807e+18;
-
-{-----------------------------------------------------------------------
-References:
-
-1) P.J. Plauger, "The Standard C Library", Prentice-Hall, 1992, Ch. 7.
-2) W.J. Cody, Jr., and W. Waite, "Software Manual For the Elementary
- Functions", Prentice-Hall, 1980.
-3) Namir Shammas, "C/C++ Mathematical Algorithms for Scientists and Engineers",
- McGraw-Hill, 1995, Ch 8.
-4) H.T. Lau, "A Numerical Library in C for Scientists and Engineers",
- CRC Press, 1994, Ch. 6.
-5) "Pentium(tm) Processor User's Manual, Volume 3: Architecture
- and Programming Manual", Intel, 1994
-+6)Уоррен Младший, "Арифметические трюки для программистов", исправленное изд.,
- 2004
-
-All angle parameters and results of trig functions are in radians.
-
-Most of the following trig and log routines map directly to Intel 80387 FPU
-floating point machine instructions. Input domains, output ranges, and
-error handling are determined largely by the FPU hardware.
-Routines coded in assembler favor the Pentium FPU pipeline architecture.
------------------------------------------------------------------------}
-
-function EAbs( D: Double ): Double;
-function EMax( const Values: array of Double ): Double;
-function EMin( const Values: array of Double ): Double;
-function ESign( X: Extended ): Integer;
-function iMax( const Values: array of Integer ): Integer;
-function iMin( const Values: array of Integer ): Integer;
-function iSign( i: Integer ): Integer;
-
-{ Trigonometric functions }
-function ArcCos(X: Extended): Extended; { IN: |X| <= 1 OUT: [0..PI] radians }
-function ArcSin(X: Extended): Extended; { IN: |X| <= 1 OUT: [-PI/2..PI/2] radians }
-
-{ ArcTan2 calculates ArcTan(Y/X), and returns an angle in the correct quadrant.
- IN: |Y| < 2^64, |X| < 2^64, X <> 0 OUT: [-PI..PI] radians }
-function ArcTan2(Y, X: Extended): Extended;
-
-{ SinCos is 2x faster than calling Sin and Cos separately for the same angle }
-procedure SinCos(Theta: Extended; var Sin, Cos: Extended) register;
-function Tan(X: Extended): Extended;
-function Cotan(X: Extended): Extended; { 1 / tan(X), X <> 0 }
-function Hypot(X, Y: Extended): Extended; { Sqrt(X**2 + Y**2) }
-
-{ Angle unit conversion routines }
-function DegToRad(Degrees: Extended): Extended; { Radians := Degrees * PI / 180}
-function RadToDeg(Radians: Extended): Extended; { Degrees := Radians * 180 / PI }
-function GradToRad(Grads: Extended): Extended; { Radians := Grads * PI / 200 }
-function RadToGrad(Radians: Extended): Extended; { Grads := Radians * 200 / PI }
-function CycleToRad(Cycles: Extended): Extended; { Radians := Cycles * 2PI }
-function RadToCycle(Radians: Extended): Extended;{ Cycles := Radians / 2PI }
-
-{ Hyperbolic functions and inverses }
-function Cosh(X: Extended): Extended;
-function Sinh(X: Extended): Extended;
-function Tanh(X: Extended): Extended;
-function ArcCosh(X: Extended): Extended; { IN: X >= 1 }
-function ArcSinh(X: Extended): Extended;
-function ArcTanh(X: Extended): Extended; { IN: |X| <= 1 }
-
-{ Logorithmic functions }
-function LnXP1(X: Extended): Extended; { Ln(X + 1), accurate for X near zero }
-function Log10(X: Extended): Extended; { Log base 10 of X}
-function Log2(X: Extended): Extended; { Log base 2 of X }
-function LogN(Base, X: Extended): Extended; { Log base N of X }
-
-{ Exponential functions }
-
-{ IntPower: Raise base to an integral power. Fast. }
-//function IntPower(Base: Extended; Exponent: Integer): Extended register;
-// -- already defined in kol.pas
-
-{ Power: Raise base to any power.
- For fractional exponents, or |exponents| > MaxInt, base must be > 0. }
-function Power(Base, Exponent: Extended): Extended;
-{$IFNDEF _D6orHigher}
-function Trunc( X: Extended ): Int64;
-{$ENDIF}
-
-{ Miscellaneous Routines }
-
-{ Frexp: Separates the mantissa and exponent of X. }
-procedure Frexp(X: Extended; var Mantissa: Extended; var Exponent: Integer) register;
-
-{ Ldexp: returns X*2**P }
-function Ldexp(X: Extended; P: Integer): Extended register;
-
-{ Ceil: Smallest integer >= X, |X| < MaxInt }
-function Ceil(X: Extended):Integer;
-
-{ Floor: Largest integer <= X, |X| < MaxInt }
-function Floor(X: Extended): Integer;
-
-{ Poly: Evaluates a uniform polynomial of one variable at value X.
- The coefficients are ordered in increasing powers of X:
- Coefficients[0] + Coefficients[1]*X + ... + Coefficients[N]*(X**N) }
-function Poly(X: Extended; const Coefficients: array of Double): Extended;
-
-{-----------------------------------------------------------------------
-Statistical functions.
-
-Common commercial spreadsheet macro names for these statistical and
-financial functions are given in the comments preceding each function.
------------------------------------------------------------------------}
-
-{ Mean: Arithmetic average of values. (AVG): SUM / N }
-function Mean(const Data: array of Double): Extended;
-
-{ Sum: Sum of values. (SUM) }
-function Sum(const Data: array of Double): Extended register;
-function SumInt(const Data: array of Integer): Integer register;
-function SumOfSquares(const Data: array of Double): Extended;
-procedure SumsAndSquares(const Data: array of Double;
- var Sum, SumOfSquares: Extended) register;
-
-{ MinValue: Returns the smallest signed value in the data array (MIN) }
-function MinValue(const Data: array of Double): Double;
-function MinIntValue(const Data: array of Integer): Integer;
-
-function Min(A,B: Integer): Integer;
-{$IFDEF _D4orHigher}
-overload;
-function Min(A,B: I64): I64; overload;
-function Min(A,B: Int64): Int64; overload;
-function Min(A,B: Single): Single; overload;
-function Min(A,B: Double): Double; overload;
-function Min(A,B: Extended): Extended; overload;
-{$ENDIF}
-
-{ MaxValue: Returns the largest signed value in the data array (MAX) }
-function MaxValue(const Data: array of Double): Double;
-function MaxIntValue(const Data: array of Integer): Integer;
-
-function Max(A,B: Integer): Integer;
-{$IFDEF _D4orHigher}
-overload;
-function Max(A,B: I64): I64; overload;
-function Max(A,B: Single): Single; overload;
-function Max(A,B: Double): Double; overload;
-function Max(A,B: Extended): Extended; overload;
-{$ENDIF}
-
-{ Standard Deviation (STD): Sqrt(Variance). aka Sample Standard Deviation }
-function StdDev(const Data: array of Double): Extended;
-
-{ MeanAndStdDev calculates Mean and StdDev in one call. }
-procedure MeanAndStdDev(const Data: array of Double; var Mean, StdDev: Extended);
-
-{ Population Standard Deviation (STDP): Sqrt(PopnVariance).
- Used in some business and financial calculations. }
-function PopnStdDev(const Data: array of Double): Extended;
-
-{ Variance (VARS): TotalVariance / (N-1). aka Sample Variance }
-function Variance(const Data: array of Double): Extended;
-
-{ Population Variance (VAR or VARP): TotalVariance/ N }
-function PopnVariance(const Data: array of Double): Extended;
-
-{ Total Variance: SUM(i=1,N)[(X(i) - Mean)**2] }
-function TotalVariance(const Data: array of Double): Extended;
-
-{ Norm: The Euclidean L2-norm. Sqrt(SumOfSquares) }
-function Norm(const Data: array of Double): Extended;
-
-{ MomentSkewKurtosis: Calculates the core factors of statistical analysis:
- the first four moments plus the coefficients of skewness and kurtosis.
- M1 is the Mean. M2 is the Variance.
- Skew reflects symmetry of distribution: M3 / (M2**(3/2))
- Kurtosis reflects flatness of distribution: M4 / Sqr(M2) }
-procedure MomentSkewKurtosis(const Data: array of Double;
- var M1, M2, M3, M4, Skew, Kurtosis: Extended);
-
-{ RandG produces random numbers with Gaussian distribution about the mean.
- Useful for simulating data with sampling errors. }
-function RandG(Mean, StdDev: Extended): Extended;
-
-{-----------------------------------------------------------------------
-Financial functions. Standard set from Quattro Pro.
-
-Parameter conventions:
-
-From the point of view of A, amounts received by A are positive and
-amounts disbursed by A are negative (e.g. a borrower's loan repayments
-are regarded by the borrower as negative).
-
-Interest rates are per payment period. 11% annual percentage rate on a
-loan with 12 payments per year would be (11 / 100) / 12 = 0.00916667
-
------------------------------------------------------------------------}
-
-type
- TPaymentTime = (ptEndOfPeriod, ptStartOfPeriod);
-
-{ Double Declining Balance (DDB) }
-function DoubleDecliningBalance(Cost, Salvage: Extended;
- Life, Period: Integer): Extended;
-
-{ Future Value (FVAL) }
-function FutureValue(Rate: Extended; NPeriods: Integer; Payment, PresentValue:
- Extended; PaymentTime: TPaymentTime): Extended;
-
-{ Interest Payment (IPAYMT) }
-function InterestPayment(Rate: Extended; Period, NPeriods: Integer; PresentValue,
- FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-
-{ Interest Rate (IRATE) }
-function InterestRate(NPeriods: Integer;
- Payment, PresentValue, FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-
-{ Internal Rate of Return. (IRR) Needs array of cash flows. }
-function InternalRateOfReturn(Guess: Extended;
- const CashFlows: array of Double): Extended;
-
-{ Number of Periods (NPER) }
-function NumberOfPeriods(Rate, Payment, PresentValue, FutureValue: Extended;
- PaymentTime: TPaymentTime): Extended;
-
-{ Net Present Value. (NPV) Needs array of cash flows. }
-function NetPresentValue(Rate: Extended; const CashFlows: array of Double;
- PaymentTime: TPaymentTime): Extended;
-
-{ Payment (PAYMT) }
-function Payment(Rate: Extended; NPeriods: Integer;
- PresentValue, FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-
-{ Period Payment (PPAYMT) }
-function PeriodPayment(Rate: Extended; Period, NPeriods: Integer;
- PresentValue, FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-
-{ Present Value (PVAL) }
-function PresentValue(Rate: Extended; NPeriods: Integer;
- Payment, FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-
-{ Straight Line depreciation (SLN) }
-function SLNDepreciation(Cost, Salvage: Extended; Life: Integer): Extended;
-
-{ Sum-of-Years-Digits depreciation (SYD) }
-function SYDDepreciation(Cost, Salvage: Extended; Life, Period: Integer): Extended;
-
-{type
- EInvalidArgument = class(EMathError) end;}
-
-{------------------------------------------------------------------------------}
-{ Integer and logical functions }
-function IsPowerOf2( i: Integer ): Boolean;
-{* TRUE, если число является степенью числа 2 }
-
-function Low1( i: Integer ): Integer;
-{* Выделяет младший бит 1 из числа i. }
-
-function Low0( i: Integer ): Integer;
-{* Выделяет младший справа бит 0 из числа i, например, 1100011 -> 100 }
-
-function count_1_bits_in_byte( x: Byte ): Byte;
-{* Подсчитывает число единичных битов в байте }
-
-function count_1_bits_in_dword( x: Integer ): Integer;
-{* Подсчитывает число единичных битов в 32-битном }
-
-
-implementation
-
-{$IFNDEF _D2orD3}
-uses SysConst;
-{$ENDIF}
-
-function EAbs( D: Double ): Double;
-begin
- Result := D;
- if Result < 0.0 then
- Result := -Result;
-end;
-
-function EMax( const Values: array of Double ): Double;
-var I: Integer;
-begin
- Result := Values[ 0 ];
- for I := 1 to High( Values ) do
- if Result < Values[ I ] then Result := Values[ I ];
-end;
-
-function EMin( const Values: array of Double ): Double;
-var I: Integer;
-begin
- Result := Values[ 0 ];
- for I := 1 to High( Values ) do
- if Result > Values[ I ] then Result := Values[ I ];
-end;
-
-function ESign( X: Extended ): Integer;
-begin
- if X < 0 then Result := -1
- else if X > 0 then Result := 1
- else Result := 1;
-end;
-
-function iMax( const Values: array of Integer ): Integer;
-var I: Integer;
-begin
- Result := Values[ 0 ];
- for I := 1 to High( Values ) do
- if Result < Values[ I ] then Result := Values[ I ];
-end;
-
-function iMin( const Values: array of Integer ): Integer;
-var I: Integer;
-begin
- Result := Values[ 0 ];
- for I := 1 to High( Values ) do
- if Result > Values[ I ] then Result := Values[ I ];
-end;
-
-{$IFDEF PAS_VERSION}
-function iSign( i: Integer ): Integer;
-begin
- if i < 0 then Result := -1
- else if i > 0 then Result := 1
- else Result := 0;
-end;
-{$ELSE}
-function iSign( i: Integer ): Integer;
-asm
- XOR EDX, EDX
- TEST EAX, EAX
- JZ @@exit
- MOV DL, 1
- JG @@exit
- OR EDX, -1
-@@exit:
- XCHG EAX, EDX
-end;
-{$ENDIF}
-
-function Annuity2(R: Extended; N: Integer; PaymentTime: TPaymentTime;
- var CompoundRN: Extended): Extended; Forward;
-function Compound(R: Extended; N: Integer): Extended; Forward;
-function RelSmall(X, Y: Extended): Boolean; Forward;
-
-type
- TPoly = record
- Neg, Pos, DNeg, DPos: Extended
- end;
-
-const
- MaxIterations = 15;
-
-{$IFNDEF MATH_NOERR}
-procedure ArgError(const Msg: string);
-begin
- raise Exception.Create(e_Math_InvalidArgument, Msg);
-end;
-{$ENDIF}
-
-function DegToRad(Degrees: Extended): Extended; { Radians := Degrees * PI / 180 }
-begin
- Result := Degrees * (PI / 180);
-end;
-
-function RadToDeg(Radians: Extended): Extended; { Degrees := Radians * 180 / PI }
-begin
- Result := Radians * (180 / PI);
-end;
-
-function GradToRad(Grads: Extended): Extended; { Radians := Grads * PI / 200 }
-begin
- Result := Grads * (PI / 200);
-end;
-
-function RadToGrad(Radians: Extended): Extended; { Grads := Radians * 200 / PI}
-begin
- Result := Radians * (200 / PI);
-end;
-
-function CycleToRad(Cycles: Extended): Extended; { Radians := Cycles * 2PI }
-begin
- Result := Cycles * (2 * PI);
-end;
-
-function RadToCycle(Radians: Extended): Extended;{ Cycles := Radians / 2PI }
-begin
- Result := Radians / (2 * PI);
-end;
-
-function LnXP1(X: Extended): Extended;
-{ Return ln(1 + X). Accurate for X near 0. }
-asm
- FLDLN2
- MOV AX,WORD PTR X+8 { exponent }
- FLD X
- CMP AX,$3FFD { .4225 }
- JB @@1
- FLD1
- FADD
- FYL2X
- JMP @@2
-@@1:
- FYL2XP1
-@@2:
- FWAIT
-end;
-
-{ Invariant: Y >= 0 & Result*X**Y = X**I. Init Y = I and Result = 1. }
-{function IntPower(X: Extended; I: Integer): Extended;
-var
- Y: Integer;
-begin
- Y := Abs(I);
- Result := 1.0;
- while Y > 0 do begin
- while not Odd(Y) do
- begin
- Y := Y shr 1;
- X := X * X
- end;
- Dec(Y);
- Result := Result * X
- end;
- if I < 0 then Result := 1.0 / Result
-end;
-}
-(* -- already defined in kol.pas
-function IntPower(Base: Extended; Exponent: Integer): Extended;
-asm
- mov ecx, eax
- cdq
- fld1 { Result := 1 }
- xor eax, edx
- sub eax, edx { eax := Abs(Exponent) }
- jz @@3
- fld Base
- jmp @@2
-@@1: fmul ST, ST { X := Base * Base }
-@@2: shr eax,1
- jnc @@1
- fmul ST(1),ST { Result := Result * X }
- jnz @@1
- fstp st { pop X from FPU stack }
- cmp ecx, 0
- jge @@3
- fld1
- fdivrp { Result := 1 / Result }
-@@3:
- fwait
-end;
-*)
-
-function Compound(R: Extended; N: Integer): Extended;
-{ Return (1 + R)**N. }
-begin
- Result := IntPower(1.0 + R, N)
-end;
-
-function Annuity2(R: Extended; N: Integer; PaymentTime: TPaymentTime;
- var CompoundRN: Extended): Extended;
-{ Set CompoundRN to Compound(R, N),
- return (1+Rate*PaymentTime)*(Compound(R,N)-1)/R;
-}
-begin
- if R = 0.0 then
- begin
- CompoundRN := 1.0;
- Result := N;
- end
- else
- begin
- { 6.1E-5 approx= 2**-14 }
- if EAbs(R) < 6.1E-5 then
- begin
- CompoundRN := Exp(N * LnXP1(R));
- Result := N*(1+(N-1)*R/2);
- end
- else
- begin
- CompoundRN := Compound(R, N);
- Result := (CompoundRN-1) / R
- end;
- if PaymentTime = ptStartOfPeriod then
- Result := Result * (1 + R);
- end;
-end; {Annuity2}
-
-
-procedure PolyX(const A: array of Double; X: Extended; var Poly: TPoly);
-{ Compute A[0] + A[1]*X + ... + A[N]*X**N and X * its derivative.
- Accumulate positive and negative terms separately. }
-var
- I: Integer;
- Neg, Pos, DNeg, DPos: Extended;
-begin
- Neg := 0.0;
- Pos := 0.0;
- DNeg := 0.0;
- DPos := 0.0;
- for I := High(A) downto Low(A) do
- begin
- DNeg := X * DNeg + Neg;
- Neg := Neg * X;
- DPos := X * DPos + Pos;
- Pos := Pos * X;
- if A[I] >= 0.0 then
- Pos := Pos + A[I]
- else
- Neg := Neg + A[I]
- end;
- Poly.Neg := Neg;
- Poly.Pos := Pos;
- Poly.DNeg := DNeg * X;
- Poly.DPos := DPos * X;
-end; {PolyX}
-
-
-function RelSmall(X, Y: Extended): Boolean;
-{ Returns True if X is small relative to Y }
-const
- C1: Double = 1E-15;
- C2: Double = 1E-12;
-begin
- Result := EAbs(X) < (C1 + C2 * EAbs(Y))
-end;
-
-{ Math functions. }
-
-function ArcCos(X: Extended): Extended;
-begin
- if X > 0.999999999999999 then
- Result := 0 {иначе -NAN !}
- else
- if X < -0.999999999999999 then
- Result := PI
- else
- Result := ArcTan2(Sqrt(1 - X*X), X);
-end;
-
-function ArcSin(X: Extended): Extended;
-begin
- Result := ArcTan2(X, Sqrt(1 - X*X))
-end;
-
-function ArcTan2(Y, X: Extended): Extended;
-asm
- FLD Y
- FLD X
- FPATAN
- FWAIT
-end;
-
-function Tan(X: Extended): Extended;
-{ Tan := Sin(X) / Cos(X) }
-asm
- FLD X
- FPTAN
- FSTP ST(0) { FPTAN pushes 1.0 after result }
- FWAIT
-end;
-
-function CoTan(X: Extended): Extended;
-{ CoTan := Cos(X) / Sin(X) = 1 / Tan(X) }
-asm
- FLD X
- FPTAN
- FDIVRP
- FWAIT
-end;
-
-function Hypot(X, Y: Extended): Extended;
-{ formula: Sqrt(X*X + Y*Y)
- implemented as: |Y|*Sqrt(1+Sqr(X/Y)), |X| < |Y| for greater precision
-var
- Temp: Extended;
-begin
- X := Abs(X);
- Y := Abs(Y);
- if X > Y then
- begin
- Temp := X;
- X := Y;
- Y := Temp;
- end;
- if X = 0 then
- Result := Y
- else // Y > X, X <> 0, so Y > 0
- Result := Y * Sqrt(1 + Sqr(X/Y));
-end;
-}
-asm
- FLD Y
- FABS
- FLD X
- FABS
- FCOM
- FNSTSW AX
- TEST AH,$45
- JNZ @@1 // if ST > ST(1) then swap
- FXCH ST(1) // put larger number in ST(1)
-@@1: FLDZ
- FCOMP
- FNSTSW AX
- TEST AH,$40 // if ST = 0, return ST(1)
- JZ @@2
- FSTP ST // eat ST(0)
- JMP @@3
-@@2: FDIV ST,ST(1) // ST := ST / ST(1)
- FMUL ST,ST // ST := ST * ST
- FLD1
- FADD // ST := ST + 1
- FSQRT // ST := Sqrt(ST)
- FMUL // ST(1) := ST * ST(1); Pop ST
-@@3: FWAIT
-end;
-
-
-procedure SinCos(Theta: Extended; var Sin, Cos: Extended);
-asm
- FLD Theta
- FSINCOS
- FSTP tbyte ptr [edx] // Cos
- FSTP tbyte ptr [eax] // Sin
- FWAIT
-end;
-
-{ Extract exponent and mantissa from X }
-procedure Frexp(X: Extended; var Mantissa: Extended; var Exponent: Integer);
-{ Mantissa ptr in EAX, Exponent ptr in EDX }
-asm
- FLD X
- PUSH EAX
- MOV dword ptr [edx], 0 { if X = 0, return 0 }
-
- FTST
- FSTSW AX
- FWAIT
- SAHF
- JZ @@Done
-
- FXTRACT // ST(1) = exponent, (pushed) ST = fraction
- FXCH
-
-// The FXTRACT instruction normalizes the fraction 1 bit higher than
-// wanted for the definition of frexp() so we need to tweak the result
-// by scaling the fraction down and incrementing the exponent.
-
- FISTP dword ptr [edx]
- FLD1
- FCHS
- FXCH
- FSCALE // scale fraction
- INC dword ptr [edx] // exponent biased to match
- FSTP ST(1) // discard -1, leave fraction as TOS
-
-@@Done:
- POP EAX
- FSTP tbyte ptr [eax]
- FWAIT
-end;
-
-function Ldexp(X: Extended; P: Integer): Extended;
- { Result := X * (2^P) }
-asm
- PUSH EAX
- FILD dword ptr [ESP]
- FLD X
- FSCALE
- POP EAX
- FSTP ST(1)
- FWAIT
-end;
-
-function Ceil(X: Extended): Integer;
-begin
- Result := Integer(Trunc(X));
- if Frac(X) > 0 then
- Inc(Result);
-end;
-
-function Floor(X: Extended): Integer;
-begin
- Result := Integer(Trunc(X));
- if Frac(X) < 0 then
- Dec(Result);
-end;
-
-{ Conversion of bases: Log.b(X) = Log.a(X) / Log.a(b) }
-
-function Log10(X: Extended): Extended;
- { Log.10(X) := Log.2(X) * Log.10(2) }
-asm
- FLDLG2 { Log base ten of 2 }
- FLD X
- FYL2X
- FWAIT
-end;
-
-function Log2(X: Extended): Extended;
-asm
- FLD1
- FLD X
- FYL2X
- FWAIT
-end;
-
-function LogN(Base, X: Extended): Extended;
-{ Log.N(X) := Log.2(X) / Log.2(N) }
-asm
- FLD1
- FLD X
- FYL2X
- FLD1
- FLD Base
- FYL2X
- FDIV
- FWAIT
-end;
-
-function Poly(X: Extended; const Coefficients: array of Double): Extended;
-{ Horner's method }
-var
- I: Integer;
-begin
- Result := Coefficients[High(Coefficients)];
- for I := High(Coefficients)-1 downto Low(Coefficients) do
- Result := Result * X + Coefficients[I];
-end;
-
-function Power(Base, Exponent: Extended): Extended;
-begin
- if Exponent = 0.0 then
- Result := 1.0 { n**0 = 1 }
- else if (Base = 0.0) and (Exponent > 0.0) then
- Result := 0.0 { 0**n = 0, n > 0 }
- else if (Frac(Exponent) = 0.0) and (EAbs(Exponent) <= MaxInt) then
- Result := IntPower(Base, Integer(Trunc(Exponent)))
- else
- Result := Exp(Exponent * Ln(Base))
-end;
-
-{$IFNDEF _D6orHigher}
-(*function Trunc1( X: Extended ): Int64;
-begin
- Result := System.Trunc( X );
-end;
-asm
- FLD qword ptr [ESP+4]
- { -> FST(0) Extended argument }
- { <- EDX:EAX Result }
-
-
- SUB ESP,12
- FNSTCW [ESP].Word // save
- FNSTCW [ESP+2].Word // scratch
- FWAIT
- OR [ESP+2].Word, $0F00 // trunc toward zero, full precision
- FLDCW [ESP+2].Word
- FISTP qword ptr [ESP+4]
- FWAIT
- FLDCW [ESP].Word
- POP ECX
- POP EAX
- POP EDX
-end;*)
-
-function Trunc( X: Extended ): Int64;
-begin
- if Abs( X ) < 1 then Result := 0 else
- if X < 0 then Result := -System.Trunc( -X )
- else Result := System.Trunc( X );
-end;
-{$ENDIF}
-
-
-{ Hyperbolic functions }
-
-function CoshSinh(X: Extended; Factor: Double): Extended;
-begin
- Result := Exp(X) / 2;
- Result := Result + Factor / Result;
-end;
-
-function Cosh(X: Extended): Extended;
-begin
- Result := CoshSinh(X, 0.25)
-end;
-
-function Sinh(X: Extended): Extended;
-begin
- Result := CoshSinh(X, -0.25)
-end;
-
-const
- MaxTanhDomain = 5678.22249441322; // Ln(MaxExtended)/2
-
-function Tanh(X: Extended): Extended;
-begin
- if X > MaxTanhDomain then
- Result := 1.0
- else if X < -MaxTanhDomain then
- Result := -1.0
- else
- begin
- Result := Exp(X);
- Result := Result * Result;
- Result := (Result - 1.0) / (Result + 1.0)
- end;
-end;
-
-function ArcCosh(X: Extended): Extended;
-begin
- if X <= 1.0 then
- Result := 0.0
- else if X > 1.0e10 then
- Result := Ln(2) + Ln(X)
- else
- Result := Ln(X + Sqrt((X - 1.0) * (X + 1.0)));
-end;
-
-function ArcSinh(X: Extended): Extended;
-var
- Neg: Boolean;
-begin
- if X = 0 then
- Result := 0
- else
- begin
- Neg := (X < 0);
- X := EAbs(X);
- if X > 1.0e10 then
- Result := Ln(2) + Ln(X)
- else
- begin
- Result := X*X;
- Result := LnXP1(X + Result / (1 + Sqrt(1 + Result)));
- end;
- if Neg then Result := -Result;
- end;
-end;
-
-function ArcTanh(X: Extended): Extended;
-var
- Neg: Boolean;
-begin
- if X = 0 then
- Result := 0
- else
- begin
- Neg := (X < 0);
- X := EAbs(X);
- if X >= 1 then
- Result := MaxExtended
- else
- Result := 0.5 * LnXP1((2.0 * X) / (1.0 - X));
- if Neg then Result := -Result;
- end;
-end;
-
-{ Statistical functions }
-
-function Mean(const Data: array of Double): Extended;
-begin
- Result := SUM(Data) / (High(Data) - Low(Data) + 1)
-end;
-
-function MinValue(const Data: array of Double): Double;
-var
- I: Integer;
-begin
- Result := Data[Low(Data)];
- for I := Low(Data) + 1 to High(Data) do
- if Result > Data[I] then
- Result := Data[I];
-end;
-
-function MinIntValue(const Data: array of Integer): Integer;
-var
- I: Integer;
-begin
- Result := Data[Low(Data)];
- for I := Low(Data) + 1 to High(Data) do
- if Result > Data[I] then
- Result := Data[I];
-end;
-
-{$IFDEF ASM_VERSION}
-function Min(A,B: Integer): Integer;
-asm
- CMP EAX, EDX
- JL @@1
- XCHG EAX, EDX
-@@1:
-end;
-{$ELSE}
-function Min(A,B: Integer): Integer;
-begin
- if A < B then
- Result := A
- else
- Result := B;
-end;
-{$ENDIF}
-
-{$IFDEF _D4orHigher}
-function Min(A,B: I64): I64;
-begin
- if Cmp64( A, B ) < 0 then
- Result := A
- else
- Result := B;
-end;
-
-function Min(A,B: Int64): Int64;
-begin
- if A < B then
- Result := A
- else
- Result := B;
-end;
-
-function Min(A,B: Single): Single;
-begin
- if A < B then
- Result := A
- else
- Result := B;
-end;
-
-function Min(A,B: Double): Double;
-begin
- if A < B then
- Result := A
- else
- Result := B;
-end;
-
-function Min(A,B: Extended): Extended;
-begin
- if A < B then
- Result := A
- else
- Result := B;
-end;
-{$ENDIF}
-
-function MaxValue(const Data: array of Double): Double;
-var
- I: Integer;
-begin
- Result := Data[Low(Data)];
- for I := Low(Data) + 1 to High(Data) do
- if Result < Data[I] then
- Result := Data[I];
-end;
-
-function MaxIntValue(const Data: array of Integer): Integer;
-var
- I: Integer;
-begin
- Result := Data[Low(Data)];
- for I := Low(Data) + 1 to High(Data) do
- if Result < Data[I] then
- Result := Data[I];
-end;
-
-{$IFDEF ASM_VERSION}
-function Max(A,B: Integer): Integer;
-asm
- CMP EAX, EDX
- JG @@1
- XCHG EAX, EDX
-@@1:
-end;
-{$ELSE}
-function Max(A,B: Integer): Integer;
-begin
- if A > B then
- Result := A
- else
- Result := B;
-end;
-{$ENDIF}
-
-{$IFDEF _D4orHigher}
-function Max(A,B: I64): I64;
-begin
- if Cmp64( A, B ) > 0 then
- Result := A
- else
- Result := B;
-end;
-
-function Max(A,B: Single): Single;
-begin
- if A > B then
- Result := A
- else
- Result := B;
-end;
-
-function Max(A,B: Double): Double;
-begin
- if A > B then
- Result := A
- else
- Result := B;
-end;
-
-function Max(A,B: Extended): Extended;
-begin
- if A > B then
- Result := A
- else
- Result := B;
-end;
-{$ENDIF}
-
-procedure MeanAndStdDev(const Data: array of Double; var Mean, StdDev: Extended);
-var
- S: Extended;
- N,I: Integer;
-begin
- N := High(Data)- Low(Data) + 1;
- if N = 1 then
- begin
- Mean := Data[0];
- StdDev := Data[0];
- Exit;
- end;
- Mean := Sum(Data) / N;
- S := 0; // sum differences from the mean, for greater accuracy
- for I := Low(Data) to High(Data) do
- S := S + Sqr(Mean - Data[I]);
- StdDev := Sqrt(S / (N - 1));
-end;
-
-procedure MomentSkewKurtosis(const Data: array of Double;
- var M1, M2, M3, M4, Skew, Kurtosis: Extended);
-var
- Sum, SumSquares, SumCubes, SumQuads, OverN, Accum, M1Sqr, S2N, S3N: Extended;
- I: Integer;
-begin
- OverN := 1 / (High(Data) - Low(Data) + 1);
- Sum := 0;
- SumSquares := 0;
- SumCubes := 0;
- SumQuads := 0;
- for I := Low(Data) to High(Data) do
- begin
- Sum := Sum + Data[I];
- Accum := Sqr(Data[I]);
- SumSquares := SumSquares + Accum;
- Accum := Accum*Data[I];
- SumCubes := SumCubes + Accum;
- SumQuads := SumQuads + Accum*Data[I];
- end;
- M1 := Sum * OverN;
- M1Sqr := Sqr(M1);
- S2N := SumSquares * OverN;
- S3N := SumCubes * OverN;
- M2 := S2N - M1Sqr;
- M3 := S3N - (M1 * 3 * S2N) + 2*M1Sqr*M1;
- M4 := (SumQuads * OverN) - (M1 * 4 * S3N) + (M1Sqr*6*S2N - 3*Sqr(M1Sqr));
- Skew := M3 * Power(M2, -3/2); // = M3 / Power(M2, 3/2)
- Kurtosis := M4 / Sqr(M2);
-end;
-
-function Norm(const Data: array of Double): Extended;
-begin
- Result := Sqrt(SumOfSquares(Data));
-end;
-
-function PopnStdDev(const Data: array of Double): Extended;
-begin
- Result := Sqrt(PopnVariance(Data))
-end;
-
-function PopnVariance(const Data: array of Double): Extended;
-begin
- Result := TotalVariance(Data) / (High(Data) - Low(Data) + 1)
-end;
-
-function RandG(Mean, StdDev: Extended): Extended;
-{ Marsaglia-Bray algorithm }
-var
- U1, S2: Extended;
-begin
- repeat
- U1 := 2*Random - 1;
- S2 := Sqr(U1) + Sqr(2*Random-1);
- until S2 < 1;
- Result := Sqrt(-2*Ln(S2)/S2) * U1 * StdDev + Mean;
-end;
-
-function StdDev(const Data: array of Double): Extended;
-begin
- Result := Sqrt(Variance(Data))
-end;
-
-procedure RaiseOverflowError; forward;
-
-function SumInt(const Data: array of Integer): Integer;
-{var
- I: Integer;
-begin
- Result := 0;
- for I := Low(Data) to High(Data) do
- Result := Result + Data[I]
-end; }
-asm // IN: EAX = ptr to Data, EDX = High(Data) = Count - 1
- // loop unrolled 4 times, 5 clocks per loop, 1.2 clocks per datum
- PUSH EBX
- MOV ECX, EAX // ecx = ptr to data
- MOV EBX, EDX
- XOR EAX, EAX
- AND EDX, not 3
- AND EBX, 3
- SHL EDX, 2
- JMP @Vector.Pointer[EBX*4]
-@Vector:
- DD @@1
- DD @@2
- DD @@3
- DD @@4
-@@4:
- ADD EAX, [ECX+12+EDX]
- JO @@RaiseOverflowError
-@@3:
- ADD EAX, [ECX+8+EDX]
- JO @@RaiseOverflowError
-@@2:
- ADD EAX, [ECX+4+EDX]
- JO @@RaiseOverflowError
-@@1:
- ADD EAX, [ECX+EDX]
- JO @@RaiseOverflowError
- SUB EDX,16
- JNS @@4
- POP EBX
- RET
-@@RaiseOverflowError:
- POP EBX
- POP ECX
- JMP RaiseOverflowError
-end;
-
-procedure RaiseOverflowError;
-begin
- {$IFNDEF MATH_NOERR}
- raise Exception.Create(e_IntOverflow, SIntOverflow);
- {$ENDIF}
-end;
-
-function SUM(const Data: array of Double): Extended;
-{var
- I: Integer;
-begin
- Result := 0.0;
- for I := Low(Data) to High(Data) do
- Result := Result + Data[I]
-end; }
-asm // IN: EAX = ptr to Data, EDX = High(Data) = Count - 1
- // Uses 4 accumulators to minimize read-after-write delays and loop overhead
- // 5 clocks per loop, 4 items per loop = 1.2 clocks per item
- FLDZ
- MOV ECX, EDX
- FLD ST(0)
- AND EDX, not 3
- FLD ST(0)
- AND ECX, 3
- FLD ST(0)
- SHL EDX, 3 // count * sizeof(Double) = count * 8
- JMP @Vector.Pointer[ECX*4]
-@Vector:
- DD @@1
- DD @@2
- DD @@3
- DD @@4
-@@4: FADD qword ptr [EAX+EDX+24] // 1
- FXCH ST(3) // 0
-@@3: FADD qword ptr [EAX+EDX+16] // 1
- FXCH ST(2) // 0
-@@2: FADD qword ptr [EAX+EDX+8] // 1
- FXCH ST(1) // 0
-@@1: FADD qword ptr [EAX+EDX] // 1
- FXCH ST(2) // 0
- SUB EDX, 32
- JNS @@4
- FADDP ST(3),ST // ST(3) := ST + ST(3); Pop ST
- FADD // ST(1) := ST + ST(1); Pop ST
- FADD // ST(1) := ST + ST(1); Pop ST
- FWAIT
-end;
-
-function SumOfSquares(const Data: array of Double): Extended;
-var
- I: Integer;
-begin
- Result := 0.0;
- for I := Low(Data) to High(Data) do
- Result := Result + Sqr(Data[I]);
-end;
-
-procedure SumsAndSquares(const Data: array of Double; var Sum, SumOfSquares: Extended);
-{var
- I: Integer;
-begin
- Sum := 0;
- SumOfSquares := 0;
- for I := Low(Data) to High(Data) do
- begin
- Sum := Sum + Data[I];
- SumOfSquares := SumOfSquares + Data[I]*Data[I];
- end;
-end; }
-asm // IN: EAX = ptr to Data
- // EDX = High(Data) = Count - 1
- // ECX = ptr to Sum
- // Est. 17 clocks per loop, 4 items per loop = 4.5 clocks per data item
- FLDZ // init Sum accumulator
- PUSH ECX
- MOV ECX, EDX
- FLD ST(0) // init Sqr1 accum.
- AND EDX, not 3
- FLD ST(0) // init Sqr2 accum.
- AND ECX, 3
- FLD ST(0) // init/simulate last data item left in ST
- SHL EDX, 3 // count * sizeof(Double) = count * 8
- JMP @Vector.Pointer[ECX*4]
-@Vector:
- DD @@1
- DD @@2
- DD @@3
- DD @@4
-@@4: FADD // Sqr2 := Sqr2 + Sqr(Data4); Pop Data4
- FLD qword ptr [EAX+EDX+24] // Load Data1
- FADD ST(3),ST // Sum := Sum + Data1
- FMUL ST,ST // Data1 := Sqr(Data1)
-@@3: FLD qword ptr [EAX+EDX+16] // Load Data2
- FADD ST(4),ST // Sum := Sum + Data2
- FMUL ST,ST // Data2 := Sqr(Data2)
- FXCH // Move Sqr(Data1) into ST(0)
- FADDP ST(3),ST // Sqr1 := Sqr1 + Sqr(Data1); Pop Data1
-@@2: FLD qword ptr [EAX+EDX+8] // Load Data3
- FADD ST(4),ST // Sum := Sum + Data3
- FMUL ST,ST // Data3 := Sqr(Data3)
- FXCH // Move Sqr(Data2) into ST(0)
- FADDP ST(3),ST // Sqr1 := Sqr1 + Sqr(Data2); Pop Data2
-@@1: FLD qword ptr [EAX+EDX] // Load Data4
- FADD ST(4),ST // Sum := Sum + Data4
- FMUL ST,ST // Sqr(Data4)
- FXCH // Move Sqr(Data3) into ST(0)
- FADDP ST(3),ST // Sqr1 := Sqr1 + Sqr(Data3); Pop Data3
- SUB EDX,32
- JNS @@4
- FADD // Sqr2 := Sqr2 + Sqr(Data4); Pop Data4
- POP ECX
- FADD // Sqr1 := Sqr2 + Sqr1; Pop Sqr2
- FXCH // Move Sum1 into ST(0)
- MOV EAX, SumOfSquares
- FSTP tbyte ptr [ECX] // Sum := Sum1; Pop Sum1
- FSTP tbyte ptr [EAX] // SumOfSquares := Sum1; Pop Sum1
- FWAIT
-end;
-
-function TotalVariance(const Data: array of Double): Extended;
-var
- Sum, SumSquares: Extended;
-begin
- SumsAndSquares(Data, Sum, SumSquares);
- Result := SumSquares - Sqr(Sum)/(High(Data) - Low(Data) + 1);
-end;
-
-function Variance(const Data: array of Double): Extended;
-begin
- Result := TotalVariance(Data) / (High(Data) - Low(Data))
-end;
-
-
-{ Depreciation functions. }
-
-function DoubleDecliningBalance(Cost, Salvage: Extended; Life, Period: Integer): Extended;
-{ dv := cost * (1 - 2/life)**(period - 1)
- DDB = (2/life) * dv
- if DDB > dv - salvage then DDB := dv - salvage
- if DDB < 0 then DDB := 0
-}
-var
- DepreciatedVal, Factor: Extended;
-begin
- Result := 0;
- if (Period < 1) or (Life < Period) or (Life < 1) or (Cost <= Salvage) then
- Exit;
-
- {depreciate everything in period 1 if life is only one or two periods}
- if ( Life <= 2 ) then
- begin
- if ( Period = 1 ) then
- DoubleDecliningBalance:=Cost-Salvage
- else
- DoubleDecliningBalance:=0; {all depreciation occurred in first period}
- exit;
- end;
- Factor := 2.0 / Life;
-
- DepreciatedVal := Cost * IntPower((1.0 - Factor), Period - 1);
- {DepreciatedVal is Cost-(sum of previous depreciation results)}
-
- Result := Factor * DepreciatedVal;
- {Nominal computed depreciation for this period. The rest of the
- function applies limits to this nominal value. }
-
- {Only depreciate until total depreciation equals cost-salvage.}
- if Result > DepreciatedVal - Salvage then
- Result := DepreciatedVal - Salvage;
-
- {No more depreciation after salvage value is reached. This is mostly a nit.
- If Result is negative at this point, it's very close to zero.}
- if Result < 0.0 then
- Result := 0.0;
-end;
-
-function SLNDepreciation(Cost, Salvage: Extended; Life: Integer): Extended;
-{ Spreads depreciation linearly over life. }
-begin
- {$IFNDEF MATH_NOERR}
- if Life < 1 then ArgError('SLNDepreciation');
- {$ENDIF}
- Result := (Cost - Salvage) / Life
-end;
-
-function SYDDepreciation(Cost, Salvage: Extended; Life, Period: Integer): Extended;
-{ SYD = (cost - salvage) * (life - period + 1) / (life*(life + 1)/2) }
-{ Note: life*(life+1)/2 = 1+2+3+...+life "sum of years"
- The depreciation factor varies from life/sum_of_years in first period = 1
- downto 1/sum_of_years in last period = life.
- Total depreciation over life is cost-salvage.}
-var
- X1, X2: Extended;
-begin
- Result := 0;
- if (Period < 1) or (Life < Period) or (Cost <= Salvage) then Exit;
- X1 := 2 * (Life - Period + 1);
- X2 := Life * (Life + 1);
- Result := (Cost - Salvage) * X1 / X2
-end;
-
-{ Discounted cash flow functions. }
-
-function InternalRateOfReturn(Guess: Extended; const CashFlows: array of Double): Extended;
-{
-Use Newton's method to solve NPV = 0, where NPV is a polynomial in
-x = 1/(1+rate). Split the coefficients into negative and postive sets:
- neg + pos = 0, so pos = -neg, so -neg/pos = 1
-Then solve:
- log(-neg/pos) = 0
-
- Let t = log(1/(1+r) = -LnXP1(r)
- then r = exp(-t) - 1
-Iterate on t, then use the last equation to compute r.
-}
-var
- T, Y: Extended;
- Poly: TPoly;
- K, Count: Integer;
-
- function ConditionP(const CashFlows: array of Double): Integer;
- { Guarantees existence and uniqueness of root. The sign of payments
- must change exactly once, the net payout must be always > 0 for
- first portion, then each payment must be >= 0.
- Returns: 0 if condition not satisfied, > 0 if condition satisfied
- and this is the index of the first value considered a payback. }
- var
- X: Double;
- I, K: Integer;
- begin
- K := High(CashFlows);
- while (K >= 0) and (CashFlows[K] >= 0.0) do Dec(K);
- Inc(K);
- if K > 0 then
- begin
- X := 0.0;
- I := 0;
- while I < K do begin
- X := X + CashFlows[I];
- if X >= 0.0 then
- begin
- K := 0;
- Break
- end;
- Inc(I)
- end
- end;
- ConditionP := K
- end;
-
-begin
- InternalRateOfReturn := 0;
- K := ConditionP(CashFlows);
- {$IFNDEF MATH_NOERR}
- if K < 0 then ArgError('InternalRateOfReturn');
- {$ENDIF}
- if K = 0 then
- begin
- {$IFNDEF MATH_NOERR}
- if Guess <= -1.0 then ArgError('InternalRateOfReturn');
- {$ENDIF}
- T := -LnXP1(Guess)
- end else
- T := 0.0;
- for Count := 1 to MaxIterations do
- begin
- PolyX(CashFlows, Exp(T), Poly);
- {$IFNDEF MATH_NOERR}
- if Poly.Pos <= Poly.Neg then ArgError('InternalRateOfReturn');
- {$ENDIF}
- if (Poly.Neg >= 0.0) or (Poly.Pos <= 0.0) then
- begin
- InternalRateOfReturn := -1.0;
- Exit;
- end;
- with Poly do
- Y := Ln(-Neg / Pos) / (DNeg / Neg - DPos / Pos);
- T := T - Y;
- if RelSmall(Y, T) then
- begin
- InternalRateOfReturn := Exp(-T) - 1.0;
- Exit;
- end
- end;
- {$IFNDEF MATH_NOERR}
- ArgError('InternalRateOfReturn');
- {$ENDIF}
-end;
-
-function NetPresentValue(Rate: Extended; const CashFlows: array of Double;
- PaymentTime: TPaymentTime): Extended;
-{ Caution: The sign of NPV is reversed from what would be expected for standard
- cash flows!}
-var
- rr: Extended;
- I: Integer;
-begin
- {$IFNDEF MATH_NOERR}
- if Rate <= -1.0 then ArgError('NetPresentValue');
- {$ENDIF}
- rr := 1/(1+Rate);
- result := 0;
- for I := High(CashFlows) downto Low(CashFlows) do
- result := rr * result + CashFlows[I];
- if PaymentTime = ptEndOfPeriod then result := rr * result;
-end;
-
-{ Annuity functions. }
-
-{---------------
-From the point of view of A, amounts received by A are positive and
-amounts disbursed by A are negative (e.g. a borrower's loan repayments
-are regarded by the borrower as negative).
-
-Given interest rate r, number of periods n:
- compound(r, n) = (1 + r)**n "Compounding growth factor"
- annuity(r, n) = (compound(r, n)-1) / r "Annuity growth factor"
-
-Given future value fv, periodic payment pmt, present value pv and type
-of payment (start, 1 , or end of period, 0) pmtTime, financial variables satisfy:
-
- fv = -pmt*(1 + r*pmtTime)*annuity(r, n) - pv*compound(r, n)
-
-For fv, pv, pmt:
-
- C := compound(r, n)
- A := (1 + r*pmtTime)*annuity(r, n)
- Compute both at once in Annuity2.
-
- if C > 1E16 then A = C/r, so:
- fv := meaningless
- pv := -pmt*(pmtTime+1/r)
- pmt := -pv*r/(1 + r*pmtTime)
- else
- fv := -pmt(1+r*pmtTime)*A - pv*C
- pv := (-pmt(1+r*pmtTime)*A - fv)/C
- pmt := (-pv*C-fv)/((1+r*pmtTime)*A)
----------------}
-
-function PaymentParts(Period, NPeriods: Integer; Rate, PresentValue,
- FutureValue: Extended; PaymentTime: TPaymentTime; var IntPmt: Extended):
- Extended;
-var
- Crn:extended; { =Compound(Rate,NPeriods) }
- Crp:extended; { =Compound(Rate,Period-1) }
- Arn:extended; { =AnnuityF(Rate,NPeriods) }
-
-begin
- {$IFNDEF MATH_NOERR}
- if Rate <= -1.0 then ArgError('PaymentParts');
- {$ENDIF}
- Crp:=Compound(Rate,Period-1);
- Arn:=Annuity2(Rate,NPeriods,PaymentTime,Crn);
- IntPmt:=(FutureValue*(Crp-1)-PresentValue*(Crn-Crp))/Arn;
- PaymentParts:=(-FutureValue-PresentValue)*Crp/Arn;
-end;
-
-function FutureValue(Rate: Extended; NPeriods: Integer; Payment, PresentValue:
- Extended; PaymentTime: TPaymentTime): Extended;
-var
- Annuity, CompoundRN: Extended;
-begin
- {$IFNDEF MATH_NOERR}
- if Rate <= -1.0 then ArgError('FutureValue');
- {$ENDIF}
- Annuity := Annuity2(Rate, NPeriods, PaymentTime, CompoundRN);
- {$IFNDEF MATH_NOERR}
- if CompoundRN > 1.0E16 then ArgError('FutureValue');
- {$ENDIF}
- FutureValue := -Payment * Annuity - PresentValue * CompoundRN
-end;
-
-function InterestPayment(Rate: Extended; Period, NPeriods: Integer; PresentValue,
- FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-var
- Crp:extended; { compound(rate,period-1)}
- Crn:extended; { compound(rate,nperiods)}
- Arn:extended; { annuityf(rate,nperiods)}
-begin
- {$IFNDEF MATH_NOERR}
- if (Rate <= -1.0)
- or (Period < 1) or (Period > NPeriods) then ArgError('InterestPayment');
- {$ENDIF}
- Crp:=Compound(Rate,Period-1);
- Arn:=Annuity2(Rate,Nperiods,PaymentTime,Crn);
- InterestPayment:=(FutureValue*(Crp-1)-PresentValue*(Crn-Crp))/Arn;
-end;
-
-function InterestRate(NPeriods: Integer;
- Payment, PresentValue, FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-{
-Given:
- First and last payments are non-zero and of opposite signs.
- Number of periods N >= 2.
-Convert data into cash flow of first, N-1 payments, last with
-first < 0, payment > 0, last > 0.
-Compute the IRR of this cash flow:
- 0 = first + pmt*x + pmt*x**2 + ... + pmt*x**(N-1) + last*x**N
-where x = 1/(1 + rate).
-Substitute x = exp(t) and apply Newton's method to
- f(t) = log(pmt*x + ... + last*x**N) / -first
-which has a unique root given the above hypotheses.
-}
-var
- X, Y, Z, First, Pmt, Last, T, ET, EnT, ET1: Extended;
- Count: Integer;
- Reverse: Boolean;
-
- function LostPrecision(X: Extended): Boolean;
- asm
- XOR EAX, EAX
- MOV BX,WORD PTR X+8
- INC EAX
- AND EBX, $7FF0
- JZ @@1
- CMP EBX, $7FF0
- JE @@1
- XOR EAX,EAX
- @@1:
- end;
-
-begin
- Result := 0;
- {$IFNDEF MATH_NOERR}
- if NPeriods <= 0 then ArgError('InterestRate');
- {$ENDIF}
- Pmt := Payment;
- if PaymentTime = ptEndOfPeriod then
- begin
- X := PresentValue;
- Y := FutureValue + Payment
- end
- else
- begin
- X := PresentValue + Payment;
- Y := FutureValue
- end;
- First := X;
- Last := Y;
- Reverse := False;
- if First * Payment > 0.0 then
- begin
- Reverse := True;
- T := First;
- First := Last;
- Last := T
- end;
- if first > 0.0 then
- begin
- First := -First;
- Pmt := -Pmt;
- Last := -Last
- end;
- {$IFNDEF MATH_NOERR}
- if (First = 0.0) or (Last < 0.0) then ArgError('InterestRate');
- {$ENDIF}
- T := 0.0; { Guess at solution }
- for Count := 1 to MaxIterations do
- begin
- EnT := Exp(NPeriods * T);
- if {LostPrecision(EnT)} ent=(ent+1) then
- begin
- Result := -Pmt / First;
- if Reverse then
- Result := Exp(-LnXP1(Result)) - 1.0;
- Exit;
- end;
- ET := Exp(T);
- ET1 := ET - 1.0;
- if ET1 = 0.0 then
- begin
- X := NPeriods;
- Y := X * (X - 1.0) / 2.0
- end
- else
- begin
- X := ET * (Exp((NPeriods - 1) * T)-1.0) / ET1;
- Y := (NPeriods * EnT - ET - X * ET) / ET1
- end;
- Z := Pmt * X + Last * EnT;
- Y := Ln(Z / -First) / ((Pmt * Y + Last * NPeriods *EnT) / Z);
- T := T - Y;
- if RelSmall(Y, T) then
- begin
- if not Reverse then T := -T;
- InterestRate := Exp(T)-1.0;
- Exit;
- end
- end;
- {$IFNDEF MATH_NOERR}
- ArgError('InterestRate');
- {$ENDIF}
-end;
-
-function NumberOfPeriods(Rate, Payment, PresentValue, FutureValue: Extended;
- PaymentTime: TPaymentTime): Extended;
-
-{ If Rate = 0 then nper := -(pv + fv) / pmt
- else cf := pv + pmt * (1 + rate*pmtTime) / rate
- nper := LnXP1(-(pv + fv) / cf) / LnXP1(rate) }
-
-var
- PVRPP: Extended; { =PV*Rate+Payment } {"initial cash flow"}
- T: Extended;
-
-begin
- {$IFNDEF MATH_NOERR}
- if Rate <= -1.0 then ArgError('NumberOfPeriods');
- {$ENDIF}
-
-{whenever both Payment and PaymentTime are given together, the PaymentTime has the effect
- of modifying the effective Payment by the interest accrued on the Payment}
-
- if ( PaymentTime=ptStartOfPeriod ) then
- Payment:=Payment*(1+Rate);
-
-{if the payment exactly matches the interest accrued periodically on the
- presentvalue, then an infinite number of payments are going to be
- required to effect a change from presentvalue to futurevalue. The
- following catches that specific error where payment is exactly equal,
- but opposite in sign to the interest on the present value. If PVRPP
- ("initial cash flow") is simply close to zero, the computation will
- be numerically unstable, but not as likely to cause an error.}
-
- PVRPP:=PresentValue*Rate+Payment;
- {$IFNDEF MATH_NOERR}
- if PVRPP=0 then ArgError('NumberOfPeriods');
- {$ENDIF}
-
- { 6.1E-5 approx= 2**-14 }
- if ( EAbs(Rate)<6.1E-5 ) then
- Result:=-(PresentValue+FutureValue)/PVRPP
- else
- begin
-
-{starting with the initial cash flow, each compounding period cash flow
- should result in the current value approaching the final value. The
- following test combines a number of simultaneous conditions to ensure
- reasonableness of the cashflow before computing the NPER.}
-
- T:= -(PresentValue+FutureValue)*Rate/PVRPP;
- {$IFNDEF MATH_NOERR}
- if T<=-1.0 then ArgError('NumberOfPeriods');
- {$ENDIF}
- Result := LnXP1(T) / LnXP1(Rate)
- end;
- NumberOfPeriods:=Result;
-end;
-
-function Payment(Rate: Extended; NPeriods: Integer; PresentValue, FutureValue:
- Extended; PaymentTime: TPaymentTime): Extended;
-var
- Annuity, CompoundRN: Extended;
-begin
- {$IFNDEF MATH_NOERR}
- if Rate <= -1.0 then ArgError('Payment');
- {$ENDIF}
- Annuity := Annuity2(Rate, NPeriods, PaymentTime, CompoundRN);
- if CompoundRN > 1.0E16 then
- Payment := -PresentValue * Rate / (1 + Integer(PaymentTime) * Rate)
- else
- Payment := (-PresentValue * CompoundRN - FutureValue) / Annuity
-end;
-
-function PeriodPayment(Rate: Extended; Period, NPeriods: Integer;
- PresentValue, FutureValue: Extended; PaymentTime: TPaymentTime): Extended;
-var
- Junk: Extended;
-begin
- {$IFNDEF MATH_NOERR}
- if (Rate <= -1.0) or (Period < 1) or (Period > NPeriods) then ArgError('PeriodPayment');
- {$ENDIF}
- PeriodPayment := PaymentParts(Period, NPeriods, Rate, PresentValue,
- FutureValue, PaymentTime, Junk);
-end;
-
-function PresentValue(Rate: Extended; NPeriods: Integer; Payment, FutureValue:
- Extended; PaymentTime: TPaymentTime): Extended;
-var
- Annuity, CompoundRN: Extended;
-begin
- {$IFNDEF MATH_NOERR}
- if Rate <= -1.0 then ArgError('PresentValue');
- {$ENDIF}
- Annuity := Annuity2(Rate, NPeriods, PaymentTime, CompoundRN);
- if CompoundRN > 1.0E16 then
- PresentValue := -(Payment / Rate * Integer(PaymentTime) * Payment)
- else
- PresentValue := (-Payment * Annuity - FutureValue) / CompoundRN
-end;
-
-{------------------------------------------------------------------------------}
-
-function IsPowerOf2( i: Integer ): Boolean; { Result = (i <> 0) and (i and (i-1) = 0); }
-asm
- OR EAX,EAX
- JZ @@exit // 0 не является степенью числа 2
- LEA EDX, [EAX-1]
- OR EAX,EDX
- SETZ AL // число является степенью 2, если (i & (i-1)) = 0, т.е. если после
- // обнуления младшей 1 в числе больше не осталось битов 1.
-@@exit:
-end;
-
-function Low1( i: Integer ): Integer; { Result := i and (-i); }
-asm
- MOV EDX, EAX
- NEG EAX
- AND EAX, EDX
-end;
-
-function Low0( i: Integer ): Integer; { Result := -i and (i+1); }
-asm
- LEA EDX, [EAX+1]
- NEG EAX
- AND EAX, EDX
-end;
-
-function count_1_bits_in_byte( x: Byte ): Byte;
- asm
- MOV CL, AL
-@@loop:
- SHR CL, 1
- JZ @@exit
- SUB AL, CL
- JMP @@loop
-@@exit:
- end;
-
-function count_1_bits_in_dword( x: Integer ): Integer;
- asm
- MOV ECX, EAX
- JMP @@go
-@@loop:
- SUB EAX, ECX
-@@go:
- SHR ECX, 1
- JNZ @@loop
- end;
-
-end.
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