fpc/rtl/inc/genmath.inc
florian f093fa9242 - killed power from system unit
* move operator ** to math unit
2005-02-08 20:25:28 +00:00

1371 lines
44 KiB
PHP

{
$Id$
This file is part of the Free Pascal run time library.
Copyright (c) 1999-2001 by Several contributors
Generic mathemtical routines (on type real)
See the file COPYING.FPC, included in this distribution,
for details about the copyright.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
**********************************************************************}
{*************************************************************************}
{ Credits }
{*************************************************************************}
{ Copyright Abandoned, 1987, Fred Fish }
{ }
{ This previously copyrighted work has been placed into the }
{ public domain by the author (Fred Fish) and may be freely used }
{ for any purpose, private or commercial. I would appreciate }
{ it, as a courtesy, if this notice is left in all copies and }
{ derivative works. Thank you, and enjoy... }
{ }
{ The author makes no warranty of any kind with respect to this }
{ product and explicitly disclaims any implied warranties of }
{ merchantability or fitness for any particular purpose. }
{-------------------------------------------------------------------------}
{ Copyright (c) 1992 Odent Jean Philippe }
{ }
{ The source can be modified as long as my name appears and some }
{ notes explaining the modifications done are included in the file. }
{-------------------------------------------------------------------------}
{ Copyright (c) 1997 Carl Eric Codere }
{-------------------------------------------------------------------------}
{$goto on}
type
TabCoef = array[0..6] of Real;
const
PIO2 = 1.57079632679489661923; { pi/2 }
PIO4 = 7.85398163397448309616E-1; { pi/4 }
SQRT2 = 1.41421356237309504880; { sqrt(2) }
SQRTH = 7.07106781186547524401E-1; { sqrt(2)/2 }
LOG2E = 1.4426950408889634073599; { 1/log(2) }
SQ2OPI = 7.9788456080286535587989E-1; { sqrt( 2/pi )}
LOGE2 = 6.93147180559945309417E-1; { log(2) }
LOGSQ2 = 3.46573590279972654709E-1; { log(2)/2 }
THPIO4 = 2.35619449019234492885; { 3*pi/4 }
TWOOPI = 6.36619772367581343075535E-1; { 2/pi }
lossth = 1.073741824e9;
MAXLOG = 8.8029691931113054295988E1; { log(2**127) }
MINLOG = -8.872283911167299960540E1; { log(2**-128) }
DP1 = 7.85398125648498535156E-1;
DP2 = 3.77489470793079817668E-8;
DP3 = 2.69515142907905952645E-15;
const sincof : TabCoef = (
1.58962301576546568060E-10,
-2.50507477628578072866E-8,
2.75573136213857245213E-6,
-1.98412698295895385996E-4,
8.33333333332211858878E-3,
-1.66666666666666307295E-1, 0);
coscof : TabCoef = (
-1.13585365213876817300E-11,
2.08757008419747316778E-9,
-2.75573141792967388112E-7,
2.48015872888517045348E-5,
-1.38888888888730564116E-3,
4.16666666666665929218E-2, 0);
{ also necessary for Int() on systems with 64bit floats (JM) }
type
{$ifdef ENDIAN_LITTLE}
float64 = packed record
low: longint;
high: longint;
end;
{$else}
float64 = packed record
high: longint;
low: longint;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_TRUNC}
type
float32 = longint;
flag = byte;
Function extractFloat64Frac0(const a: float64): longint;
Begin
extractFloat64Frac0 := a.high and $000FFFFF;
End;
Function extractFloat64Frac1(const a: float64): longint;
Begin
extractFloat64Frac1 := a.low;
End;
Function extractFloat64Exp(const a: float64): smallint;
Begin
extractFloat64Exp:= ( a.high shr 20 ) AND $7FF;
End;
Function extractFloat64Frac(const a: float64): int64;
Begin
extractFloat64Frac:=int64(a) and $000FFFFFFFFFFFFF;
End;
Function extractFloat64Sign(const a: float64) : flag;
Begin
extractFloat64Sign := a.high shr 31;
End;
Procedure shortShift64Left(a0:longint; a1:longint; count:smallint; VAR z0Ptr:longint; VAR z1Ptr:longint );
Begin
z1Ptr := a1 shl count;
if count = 0 then
z0Ptr := a0
else
z0Ptr := ( a0 shl count ) OR ( a1 shr ( ( - count ) AND 31 ) );
End;
function float64_to_int32_round_to_zero(a: float64 ): longint;
Var
aSign: flag;
aExp, shiftCount: smallint;
aSig0, aSig1, absZ, aSigExtra: longint;
z: longint;
Begin
aSig1 := extractFloat64Frac1( a );
aSig0 := extractFloat64Frac0( a );
aExp := extractFloat64Exp( a );
aSign := extractFloat64Sign( a );
shiftCount := aExp - $413;
if 0<=shiftCount then
Begin
if (aExp=$7FF) and ((aSig0 or aSig1)<>0) then
HandleError(207);
shortShift64Left(aSig0 OR $00100000, aSig1, shiftCount, absZ, aSigExtra );
End
else
Begin
if aExp<$3FF then
begin
float64_to_int32_round_to_zero := 0;
exit;
end;
aSig0 := aSig0 or $00100000;
aSigExtra := ( aSig0 shl ( shiftCount and 31 ) ) OR aSig1;
absZ := aSig0 shr ( - shiftCount );
End;
if aSign<>0 then
z:=-absZ
else
z:=absZ;
if ((aSign<>0) xor (z<0)) AND (z<>0) then
HandleError(207);
float64_to_int32_round_to_zero := z;
End;
{$ifndef VER1_0}
function float64_to_int64_round_to_zero(a : float64) : int64;
var
aSign : flag;
aExp, shiftCount : smallint;
aSig : int64;
z : int64;
begin
aSig:=extractFloat64Frac(a);
aExp:=extractFloat64Exp(a);
aSign:=extractFloat64Sign(a);
if aExp<>0 then
aSig:=aSig or $0010000000000000;
shiftCount:= aExp-$433;
if 0<=shiftCount then
begin
if aExp>=$43e then
begin
if int64(a)<>$C3E0000000000000 then
HandleError(207);
{ pascal doesn't know Inf for int64 }
HandleError(207);
end;
z:=aSig shl shiftCount;
end
else
begin
if aExp<$3fe then
begin
result:=0;
exit;
end;
z:=aSig shr -shiftCount;
{
if (aSig shl (shiftCount and 63))<>0 then
float_exception_flags |= float_flag_inexact;
}
end;
if aSign<>0 then
z:=-z;
result:=z;
end;
{$endif VER1_0}
Function ExtractFloat32Frac(a : Float32) : longint;
Begin
ExtractFloat32Frac := A AND $007FFFFF;
End;
Function extractFloat32Exp( a: float32 ): smallint;
Begin
extractFloat32Exp := (a shr 23) AND $FF;
End;
Function extractFloat32Sign( a: float32 ): Flag;
Begin
extractFloat32Sign := a shr 31;
End;
Function float32_to_int32_round_to_zero( a: Float32 ): longint;
Var
aSign : flag;
aExp, shiftCount : smallint;
aSig : longint;
z : longint;
Begin
aSig := extractFloat32Frac( a );
aExp := extractFloat32Exp( a );
aSign := extractFloat32Sign( a );
shiftCount := aExp - $9E;
if ( 0 <= shiftCount ) then
Begin
if ( a <> Float32($CF000000) ) then
Begin
if ( (aSign=0) or ( ( aExp = $FF ) and (aSig<>0) ) ) then
Begin
HandleError(207);
exit;
end;
End;
HandleError(207);
exit;
End
else
if ( aExp <= $7E ) then
Begin
float32_to_int32_round_to_zero := 0;
exit;
End;
aSig := ( aSig or $00800000 ) shl 8;
z := aSig shr ( - shiftCount );
if ( aSign<>0 ) then z := - z;
float32_to_int32_round_to_zero := z;
End;
{$ifdef INTERNCONSTINTF}
function fpc_trunc_real(d : real) : int64;compilerproc;
{$else}
function trunc(d : real) : int64;[internconst:fpc_in_const_trunc];
{$endif}
var
{$ifdef cpuarm}
l: longint;
{$endif cpuarm}
f32 : float32;
f64 : float64;
Begin
{ in emulation mode the real is equal to a single }
{ otherwise in fpu mode, it is equal to a double }
{ extended is not supported yet. }
if sizeof(D) > 8 then
HandleError(255);
if sizeof(D)=8 then
begin
move(d,f64,sizeof(f64));
{$ifdef cpuarm}
{ the arm fpu has a strange opinion how a double has to be stored }
l:=f64.low;
f64.low:=f64.high;
f64.high:=l;
{$endif cpuarm}
{$ifdef VER1_0}
result:=float64_to_int32_round_to_zero(f64);
{$else VER1_0}
result:=float64_to_int64_round_to_zero(f64);
{$endif VER1_0}
end
else
begin
move(d,f32,sizeof(f32));
result:=float32_to_int32_round_to_zero(f32);
end;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_INT}
{$ifdef SUPPORT_DOUBLE}
{ straight Pascal translation of the code for __trunc() in }
{ the file sysdeps/libm-ieee754/s_trunc.c of glibc (JM) }
{$ifdef INTERNCONSTINTF}
function fpc_int_real(d: double): double;compilerproc;
{$else}
function int(d: double): double;[internconst:fpc_in_const_int];
{$endif}
var
i0, j0: longint;
i1: cardinal;
sx: longint;
f64 : float64;
begin
f64:=float64(d);
{$ifdef cpuarm}
{ the arm fpu has a strange opinion how a double has to be stored }
i0:=f64.low;
f64.low:=f64.high;
f64.high:=i0;
{$endif cpuarm}
i0 := f64.high;
i1 := cardinal(f64.low);
sx := i0 and $80000000;
j0 := ((i0 shr 20) and $7ff) - $3ff;
if (j0 < 20) then
begin
if (j0 < 0) then
begin
{ the magnitude of the number is < 1 so the result is +-0. }
f64.high := sx;
f64.low := 0;
end
else
begin
f64.high := sx or (i0 and not($fffff shr j0));
f64.low := 0;
end
end
else if (j0 > 51) then
begin
if (j0 = $400) then
{ d is inf or NaN }
exit(d + d); { don't know why they do this (JM) }
end
else
begin
f64.high := i0;
f64.low := longint(i1 and not(cardinal($ffffffff) shr (j0 - 20)));
end;
{$ifdef cpuarm}
{ the arm fpu has a strange opinion how a double has to be stored }
i0:=f64.low;
f64.low:=f64.high;
f64.high:=i0;
{$endif cpuarm}
result:=double(f64);
end;
{$else SUPPORT_DOUBLE}
{$ifdef INTERNCONSTINTF}
function fpc_int_real(d : real) : real;compilerproc;
{$else}
function int(d : real) : real;[internconst:fpc_in_const_int];
{$endif}
begin
{ this will be correct since real = single in the case of }
{ the motorola version of the compiler... }
result:=real(trunc(d));
end;
{$endif SUPPORT_DOUBLE}
{$endif}
{$ifndef FPC_SYSTEM_HAS_ABS}
{$ifdef SUPPORT_DOUBLE}
{$ifdef INTERNCONSTINTF}
function fpc_abs_real(d : Double) : Double;compilerproc;
{$else}
function abs(d : Double) : Double;[public,alias:'FPC_ABS_REAL'];
{$endif}
begin
if (d<0.0) then
result := -d
else
result := d ;
end;
{$else}
{$ifdef INTERNCONSTINTF}
function fpc_abs_real(d : Double) : Double;compilerproc;
{$else}
function abs(d : Real) : Real;[public,alias:'FPC_ABS_REAL'];
{$endif}
begin
if (d<0.0) then
result := -d
else
result := d ;
end;
{$endif}
{$ifndef INTERNCONSTINTF}
{$ifdef hascompilerproc}
function fpc_abs_real(d:Real):Real;compilerproc; external name 'FPC_ABS_REAL';
{$endif hascompilerproc}
{$endif}
{$endif not FPC_SYSTEM_HAS_ABS}
{$ifndef SYSTEM_HAS_FREXP}
function frexp(x:Real; var e:Integer ):Real;
{* frexp() extracts the exponent from x. It returns an integer *}
{* power of two to expnt and the significand between 0.5 and 1 *}
{* to y. Thus x = y * 2**expn. *}
begin
e :=0;
if (abs(x)<0.5) then
While (abs(x)<0.5) do
begin
x := x*2;
Dec(e);
end
else
While (abs(x)>1) do
begin
x := x/2;
Inc(e);
end;
frexp := x;
end;
{$endif not SYSTEM_HAS_FREXP}
{$ifndef SYSTEM_HAS_LDEXP}
function ldexp( x: Real; N: Integer):Real;
{* ldexp() multiplies x by 2**n. *}
var r : Real;
begin
R := 1;
if N>0 then
while N>0 do
begin
R:=R*2;
Dec(N);
end
else
while N<0 do
begin
R:=R/2;
Inc(N);
end;
ldexp := x * R;
end;
{$endif not SYSTEM_HAS_LDEXP}
function polevl(var x:Real; var Coef:TabCoef; N:Integer):Real;
{*****************************************************************}
{ Evaluate polynomial }
{*****************************************************************}
{ }
{ SYNOPSIS: }
{ }
{ int N; }
{ double x, y, coef[N+1], polevl[]; }
{ }
{ y = polevl( x, coef, N ); }
{ }
{ DESCRIPTION: }
{ }
{ Evaluates polynomial of degree N: }
{ }
{ 2 N }
{ y = C + C x + C x +...+ C x }
{ 0 1 2 N }
{ }
{ Coefficients are stored in reverse order: }
{ }
{ coef[0] = C , ..., coef[N] = C . }
{ N 0 }
{ }
{ The function p1evl() assumes that coef[N] = 1.0 and is }
{ omitted from the array. Its calling arguments are }
{ otherwise the same as polevl(). }
{ }
{ SPEED: }
{ }
{ In the interest of speed, there are no checks for out }
{ of bounds arithmetic. This routine is used by most of }
{ the functions in the library. Depending on available }
{ equipment features, the user may wish to rewrite the }
{ program in microcode or assembly language. }
{*****************************************************************}
var ans : Real;
i : Integer;
begin
ans := Coef[0];
for i:=1 to N do
ans := ans * x + Coef[i];
polevl:=ans;
end;
function p1evl(var x:Real; var Coef:TabCoef; N:Integer):Real;
{ }
{ Evaluate polynomial when coefficient of x is 1.0. }
{ Otherwise same as polevl. }
{ }
var
ans : Real;
i : Integer;
begin
ans := x + Coef[0];
for i:=1 to N-1 do
ans := ans * x + Coef[i];
p1evl := ans;
end;
{$ifndef FPC_SYSTEM_HAS_SQR}
{$ifdef INTERNCONSTINTF}
function fpc_sqr_real(d : Real) : Real;compilerproc;{$ifdef MATHINLINE}inline;{$endif}
{$else}
function sqr(d : Real) : Real;[internconst:fpc_in_const_sqr];
{$endif}
begin
result := d*d;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_PI}
{$ifdef INTERNCONSTINTF}
function fpc_pi_real : Real;compilerproc;{$ifdef MATHINLINE}inline;{$endif}
{$else}
function pi : Real;[internconst:fpc_in_const_pi];
{$endif}
begin
result := 3.1415926535897932385;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_SQRT}
{$ifdef INTERNCONSTINTF}
function fpc_sqrt_real(d:Real):Real;compilerproc;
{$else}
{$ifdef hascompilerproc}
function fpc_sqrt_real(d:Real):Real;compilerproc; external name 'FPC_SQRT_REAL';
{$endif hascompilerproc}
function sqrt(d:Real):Real;[internconst:fpc_in_const_sqrt];[public, alias: 'FPC_SQRT_REAL'];
{$endif}
{*****************************************************************}
{ Square root }
{*****************************************************************}
{ }
{ SYNOPSIS: }
{ }
{ double x, y, sqrt(); }
{ }
{ y = sqrt( x ); }
{ }
{ DESCRIPTION: }
{ }
{ Returns the square root of x. }
{ }
{ Range reduction involves isolating the power of two of the }
{ argument and using a polynomial approximation to obtain }
{ a rough value for the square root. Then Heron's iteration }
{ is used three times to converge to an accurate value. }
{*****************************************************************}
var e : Integer;
w,z : Real;
begin
if( d <= 0.0 ) then
begin
if( d < 0.0 ) then
HandleError(207);
result := 0.0;
end
else
begin
w := d;
{ separate exponent and significand }
z := frexp( d, e );
{ approximate square root of number between 0.5 and 1 }
{ relative error of approximation = 7.47e-3 }
d := 4.173075996388649989089E-1 + 5.9016206709064458299663E-1 * z;
{ adjust for odd powers of 2 }
if odd(e) then
d := d*SQRT2;
{ re-insert exponent }
d := ldexp( d, (e div 2) );
{ Newton iterations: }
d := 0.5*(d + w/d);
d := 0.5*(d + w/d);
d := 0.5*(d + w/d);
d := 0.5*(d + w/d);
d := 0.5*(d + w/d);
d := 0.5*(d + w/d);
result := d;
end;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_EXP}
{$ifdef INTERNCONSTINTF}
function fpc_exp_real(d:Real):Real;compilerproc;
{$else}
function Exp(d:Real):Real;[internconst:fpc_in_const_exp];
{$endif}
{*****************************************************************}
{ Exponential Function }
{*****************************************************************}
{ }
{ SYNOPSIS: }
{ }
{ double x, y, exp(); }
{ }
{ y = exp( x ); }
{ }
{ DESCRIPTION: }
{ }
{ Returns e (2.71828...) raised to the x power. }
{ }
{ Range reduction is accomplished by separating the argument }
{ into an integer k and fraction f such that }
{ }
{ x k f }
{ e = 2 e. }
{ }
{ A Pade' form of degree 2/3 is used to approximate exp(f)- 1 }
{ in the basic range [-0.5 ln 2, 0.5 ln 2]. }
{*****************************************************************}
const P : TabCoef = (
1.26183092834458542160E-4,
3.02996887658430129200E-2,
1.00000000000000000000E0, 0, 0, 0, 0);
Q : TabCoef = (
3.00227947279887615146E-6,
2.52453653553222894311E-3,
2.27266044198352679519E-1,
2.00000000000000000005E0, 0 ,0 ,0);
C1 = 6.9335937500000000000E-1;
C2 = 2.1219444005469058277E-4;
var n : Integer;
px, qx, xx : Real;
begin
if( d > MAXLOG) then
HandleError(205)
else
if( d < MINLOG ) then
begin
HandleError(205);
end
else
begin
{ Express e**x = e**g 2**n }
{ = e**g e**( n loge(2) ) }
{ = e**( g + n loge(2) ) }
px := d * LOG2E;
qx := Trunc( px + 0.5 ); { Trunc() truncates toward -infinity. }
n := Trunc(qx);
d := d - qx * C1;
d := d + qx * C2;
{ rational approximation for exponential }
{ of the fractional part: }
{ e**x - 1 = 2x P(x**2)/( Q(x**2) - P(x**2) ) }
xx := d * d;
px := d * polevl( xx, P, 2 );
d := px/( polevl( xx, Q, 3 ) - px );
d := ldexp( d, 1 );
d := d + 1.0;
d := ldexp( d, n );
result := d;
end;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_ROUND}
{$ifdef INTERNCONSTINTF}
function fpc_round_real(d : Real) : int64;compilerproc;
{$else}
{$ifdef hascompilerproc}
function round(d : Real) : int64;{$ifndef INTERNCONSTINTF}[internconst:fpc_in_const_round];{$endif} external name 'FPC_ROUND';
function fpc_round(d : Real) : int64;[public, alias:'FPC_ROUND'];{$ifdef hascompilerproc}compilerproc;{$endif hascompilerproc}
{$else}
function round(d : Real) : int64;{$ifndef INTERNCONSTINTF}[internconst:fpc_in_const_round];{$endif}
{$endif hascompilerproc}
{$endif}
var
fr: Real;
tr: Int64;
Begin
fr := abs(Frac(d));
tr := Trunc(d);
if fr > 0.5 then
if d >= 0 then
result:=tr+1
else
result:=tr-1
else
if fr < 0.5 then
result:=tr
else { fr = 0.5 }
{ check sign to decide ... }
{ as in Turbo Pascal... }
if d >= 0.0 then
result:=tr+1
else
result:=tr;
end;
{$endif}
{$ifdef FPC_CURRENCY_IS_INT64}
function trunc(c : currency) : int64;
type
tmyrec = record
i: int64;
end;
begin
result := int64(tmyrec(c)) div 10000
end;
function trunc(c : comp) : int64;
begin
result := c
end;
function round(c : currency) : int64;
type
tmyrec = record
i: int64;
end;
var
rem, absrem: longint;
begin
{ (int64(tmyrec(c))(+/-)5000) div 10000 can overflow }
result := int64(tmyrec(c)) div 10000;
rem := int64(tmyrec(c)) - result * 10000;
absrem := abs(rem);
if (absrem > 5000) or
((absrem = 5000) and
(rem > 0)) then
if (rem > 0) then
inc(result)
else
dec(result);
end;
function round(c : comp) : int64;
begin
result := c
end;
{$endif FPC_CURRENCY_IS_INT64}
{$ifndef FPC_SYSTEM_HAS_LN}
{$ifdef INTERNCONSTINTF}
function fpc_ln_real(d:Real):Real;compilerproc;
{$else}
function Ln(d:Real):Real;[internconst:fpc_in_const_ln];
{$endif}
{*****************************************************************}
{ Natural Logarithm }
{*****************************************************************}
{ }
{ SYNOPSIS: }
{ }
{ double x, y, log(); }
{ }
{ y = ln( x ); }
{ }
{ DESCRIPTION: }
{ }
{ Returns the base e (2.718...) logarithm of x. }
{ }
{ The argument is separated into its exponent and fractional }
{ parts. If the exponent is between -1 and +1, the logarithm }
{ of the fraction is approximated by }
{ }
{ log(1+x) = x - 0.5 x**2 + x**3 P(x)/Q(x). }
{ }
{ Otherwise, setting z = 2(x-1)/x+1), }
{ }
{ log(x) = z + z**3 P(z)/Q(z). }
{ }
{*****************************************************************}
const P : TabCoef = (
{ Coefficients for log(1+x) = x - x**2/2 + x**3 P(x)/Q(x)
1/sqrt(2) <= x < sqrt(2) }
4.58482948458143443514E-5,
4.98531067254050724270E-1,
6.56312093769992875930E0,
2.97877425097986925891E1,
6.06127134467767258030E1,
5.67349287391754285487E1,
1.98892446572874072159E1);
Q : TabCoef = (
1.50314182634250003249E1,
8.27410449222435217021E1,
2.20664384982121929218E2,
3.07254189979530058263E2,
2.14955586696422947765E2,
5.96677339718622216300E1, 0);
{ Coefficients for log(x) = z + z**3 P(z)/Q(z),
where z = 2(x-1)/(x+1)
1/sqrt(2) <= x < sqrt(2) }
R : TabCoef = (
-7.89580278884799154124E-1,
1.63866645699558079767E1,
-6.41409952958715622951E1, 0, 0, 0, 0);
S : TabCoef = (
-3.56722798256324312549E1,
3.12093766372244180303E2,
-7.69691943550460008604E2, 0, 0, 0, 0);
var e : Integer;
z, y : Real;
Label Ldone;
begin
if( d <= 0.0 ) then
HandleError(207);
d := frexp( d, e );
{ logarithm using log(x) = z + z**3 P(z)/Q(z),
where z = 2(x-1)/x+1) }
if( (e > 2) or (e < -2) ) then
begin
if( d < SQRTH ) then
begin
{ 2( 2x-1 )/( 2x+1 ) }
Dec(e, 1);
z := d - 0.5;
y := 0.5 * z + 0.5;
end
else
begin
{ 2 (x-1)/(x+1) }
z := d - 0.5;
z := z - 0.5;
y := 0.5 * d + 0.5;
end;
d := z / y;
{ /* rational form */ }
z := d*d;
z := d + d * ( z * polevl( z, R, 2 ) / p1evl( z, S, 3 ) );
goto ldone;
end;
{ logarithm using log(1+x) = x - .5x**2 + x**3 P(x)/Q(x) }
if( d < SQRTH ) then
begin
Dec(e, 1);
d := ldexp( d, 1 ) - 1.0; { 2x - 1 }
end
else
d := d - 1.0;
{ rational form }
z := d*d;
y := d * ( z * polevl( d, P, 6 ) / p1evl( d, Q, 6 ) );
y := y - ldexp( z, -1 ); { y - 0.5 * z }
z := d + y;
ldone:
{ recombine with exponent term }
if( e <> 0 ) then
begin
y := e;
z := z - y * 2.121944400546905827679e-4;
z := z + y * 0.693359375;
end;
result:= z;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_SIN}
{$ifdef INTERNCONSTINTF}
function fpc_Sin_real(d:Real):Real;compilerproc;
{$else}
function Sin(d:Real):Real;[internconst:fpc_in_const_sin];
{$endif}
{*****************************************************************}
{ Circular Sine }
{*****************************************************************}
{ }
{ SYNOPSIS: }
{ }
{ double x, y, sin(); }
{ }
{ y = sin( x ); }
{ }
{ DESCRIPTION: }
{ }
{ Range reduction is into intervals of pi/4. The reduction }
{ error is nearly eliminated by contriving an extended }
{ precision modular arithmetic. }
{ }
{ Two polynomial approximating functions are employed. }
{ Between 0 and pi/4 the sine is approximated by }
{ x + x**3 P(x**2). }
{ Between pi/4 and pi/2 the cosine is represented as }
{ 1 - x**2 Q(x**2). }
{*****************************************************************}
var y, z, zz : Real;
j, sign : Integer;
begin
{ make argument positive but save the sign }
sign := 1;
if( d < 0 ) then
begin
d := -d;
sign := -1;
end;
{ above this value, approximate towards 0 }
if( d > lossth ) then
begin
result := 0.0;
exit;
end;
y := Trunc( d/PIO4 ); { integer part of x/PIO4 }
{ strip high bits of integer part to prevent integer overflow }
z := ldexp( y, -4 );
z := Trunc(z); { integer part of y/8 }
z := y - ldexp( z, 4 ); { y - 16 * (y/16) }
j := Trunc(z); { convert to integer for tests on the phase angle }
{ map zeros to origin }
{ typecast is to avoid "can't determine which overloaded function }
{ to call" }
if odd( longint(j) ) then
begin
inc(j);
y := y + 1.0;
end;
j := j and 7; { octant modulo 360 degrees }
{ reflect in x axis }
if( j > 3) then
begin
sign := -sign;
dec(j, 4);
end;
{ Extended precision modular arithmetic }
z := ((d - y * DP1) - y * DP2) - y * DP3;
zz := z * z;
if( (j=1) or (j=2) ) then
y := 1.0 - ldexp(zz,-1) + zz * zz * polevl( zz, coscof, 5 )
else
{ y = z + z * (zz * polevl( zz, sincof, 5 )); }
y := z + z * z * z * polevl( zz, sincof, 5 );
if(sign < 0) then
y := -y;
result := y;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_COS}
{$ifdef INTERNCONSTINTF}
function fpc_Cos_real(d:Real):Real;compilerproc;
{$else}
function Cos(d:Real):Real;[internconst:fpc_in_const_cos];
{$endif}
{*****************************************************************}
{ Circular cosine }
{*****************************************************************}
{ }
{ Circular cosine }
{ }
{ SYNOPSIS: }
{ }
{ double x, y, cos(); }
{ }
{ y = cos( x ); }
{ }
{ DESCRIPTION: }
{ }
{ Range reduction is into intervals of pi/4. The reduction }
{ error is nearly eliminated by contriving an extended }
{ precision modular arithmetic. }
{ }
{ Two polynomial approximating functions are employed. }
{ Between 0 and pi/4 the cosine is approximated by }
{ 1 - x**2 Q(x**2). }
{ Between pi/4 and pi/2 the sine is represented as }
{ x + x**3 P(x**2). }
{*****************************************************************}
var y, z, zz : Real;
j, sign : Integer;
i : LongInt;
begin
{ make argument positive }
sign := 1;
if( d < 0 ) then
d := -d;
{ above this value, round towards zero }
if( d > lossth ) then
begin
result := 0.0;
exit;
end;
y := Trunc( d/PIO4 );
z := ldexp( y, -4 );
z := Trunc(z); { integer part of y/8 }
z := y - ldexp( z, 4 ); { y - 16 * (y/16) }
{ integer and fractional part modulo one octant }
i := Trunc(z);
if odd( i ) then { map zeros to origin }
begin
inc(i);
y := y + 1.0;
end;
j := i and 07;
if( j > 3) then
begin
dec(j,4);
sign := -sign;
end;
if( j > 1 ) then
sign := -sign;
{ Extended precision modular arithmetic }
z := ((d - y * DP1) - y * DP2) - y * DP3;
zz := z * z;
if( (j=1) or (j=2) ) then
{ y = z + z * (zz * polevl( zz, sincof, 5 )); }
y := z + z * z * z * polevl( zz, sincof, 5 )
else
y := 1.0 - ldexp(zz,-1) + zz * zz * polevl( zz, coscof, 5 );
if(sign < 0) then
y := -y;
result := y ;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_ARCTAN}
{$ifdef INTERNCONSTINTF}
function fpc_ArcTan_real(d:Real):Real;compilerproc;
{$else}
function ArcTan(d:Real):Real;[internconst:fpc_in_const_arctan];
{$endif}
{*****************************************************************}
{ Inverse circular tangent (arctangent) }
{*****************************************************************}
{ }
{ SYNOPSIS: }
{ }
{ double x, y, atan(); }
{ }
{ y = atan( x ); }
{ }
{ DESCRIPTION: }
{ }
{ Returns radian angle between -pi/2 and +pi/2 whose tangent }
{ is x. }
{ }
{ Range reduction is from four intervals into the interval }
{ from zero to tan( pi/8 ). The approximant uses a rational }
{ function of degree 3/4 of the form x + x**3 P(x)/Q(x). }
{*****************************************************************}
const P : TabCoef = (
-8.40980878064499716001E-1,
-8.83860837023772394279E0,
-2.18476213081316705724E1,
-1.48307050340438946993E1, 0, 0, 0);
Q : TabCoef = (
1.54974124675307267552E1,
6.27906555762653017263E1,
9.22381329856214406485E1,
4.44921151021319438465E1, 0, 0, 0);
{ tan( 3*pi/8 ) }
T3P8 = 2.41421356237309504880;
{ tan( pi/8 ) }
TP8 = 0.41421356237309504880;
var y,z : Real;
Sign : Integer;
begin
{ make argument positive and save the sign }
sign := 1;
if( d < 0.0 ) then
begin
sign := -1;
d := -d;
end;
{ range reduction }
if( d > T3P8 ) then
begin
y := PIO2;
d := -( 1.0/d );
end
else if( d > TP8 ) then
begin
y := PIO4;
d := (d-1.0)/(d+1.0);
end
else
y := 0.0;
{ rational form in x**2 }
z := d * d;
y := y + ( polevl( z, P, 3 ) / p1evl( z, Q, 4 ) ) * z * d + d;
if( sign < 0 ) then
y := -y;
result := y;
end;
{$endif}
{$ifndef FPC_SYSTEM_HAS_FRAC}
{$ifdef INTERNCONSTINTF}
function fpc_frac_real(d : Real) : Real;compilerproc;
{$else}
function frac(d : Real) : Real;[internconst:fpc_in_const_frac];
{$endif}
begin
result := d - Int(d);
end;
{$endif}
{$ifdef FPC_INCLUDE_SOFTWARE_INT64_TO_DOUBLE}
{$ifndef FPC_SYSTEM_HAS_QWORD_TO_DOUBLE}
function fpc_qword_to_double(q : qword): double; compilerproc;
begin
result:=dword(q and $ffffffff)+dword(q shr 32)*4294967296.0;
end;
{$endif FPC_SYSTEM_HAS_INT64_TO_DOUBLE}
{$ifndef FPC_SYSTEM_HAS_INT64_TO_DOUBLE}
function fpc_int64_to_double(i : int64): double; compilerproc;
begin
if i<0 then
result:=-double(qword(-i))
else
result:=qword(i);
end;
{$endif FPC_SYSTEM_HAS_INT64_TO_DOUBLE}
{$endif FPC_INCLUDE_SOFTWARE_INT64_TO_DOUBLE}
{$ifdef SUPPORT_DOUBLE}
{****************************************************************************
Helper routines to support old TP styled reals
****************************************************************************}
{$ifndef FPC_SYSTEM_HAS_REAL2DOUBLE}
function real2double(r : real48) : double;
var
res : array[0..7] of byte;
exponent : word;
begin
{ copy mantissa }
res[0]:=0;
res[1]:=r[1] shl 5;
res[2]:=(r[1] shr 3) or (r[2] shl 5);
res[3]:=(r[2] shr 3) or (r[3] shl 5);
res[4]:=(r[3] shr 3) or (r[4] shl 5);
res[5]:=(r[4] shr 3) or (r[5] and $7f) shl 5;
res[6]:=(r[5] and $7f) shr 3;
{ copy exponent }
{ correct exponent: }
exponent:=(word(r[0])+(1023-129));
res[6]:=res[6] or ((exponent and $f) shl 4);
res[7]:=exponent shr 4;
{ set sign }
res[7]:=res[7] or (r[5] and $80);
real2double:=double(res);
end;
{$endif FPC_SYSTEM_HAS_REAL2DOUBLE}
{$endif SUPPORT_DOUBLE}
{
$Log$
Revision 1.31 2005-02-08 20:25:28 florian
- killed power from system unit
* move operator ** to math unit
Revision 1.30 2004/12/05 16:43:57 jonas
* fixed power() in genmath.inc (code duplication from math.pp for **
support!)
* fixed power() in math.pp to give an error from 0^0
Revision 1.29 2004/11/21 15:35:23 peter
* float routines all use internproc and compilerproc helpers
Revision 1.28 2004/11/20 15:49:21 jonas
* some compilation fixes for powerpc after all the internconst and
internproc changes, still crashes with internalerror(88) for ppc1
on real2str.inc(193,39)
Revision 1.27 2004/10/09 21:00:46 jonas
+ cgenmath with libc math functions. Faster than the routines in genmath
and also have full double support (exp() only has support for values in
the single range in genmath, for example). Used in FPC_USE_LIBC is
defined
* several fixes to allow compilation with -dHASINLINE, but internalerrors
because of missing support for inlining assembler code
Revision 1.26 2004/10/03 14:09:39 florian
* fixed trunc for abs(value) < 1
Revision 1.25 2004/10/03 14:00:21 florian
+ made generic trunc 64 bit aware
Revision 1.24 2004/05/31 20:25:04 peter
* removed warnings
Revision 1.23 2004/03/13 18:33:52 florian
* fixed some arm related real stuff
Revision 1.22 2004/03/11 22:39:53 florian
* arm startup code fixed
* made some generic math code more readable
Revision 1.21 2004/02/04 14:15:57 florian
* fixed generic system.int(...)
Revision 1.20 2004/01/24 18:15:58 florian
* fixed small bugs
* fixed some arm issues
Revision 1.18 2004/01/06 21:34:07 peter
* abs(double) added
* abs() alias
Revision 1.17 2004/01/02 17:19:04 jonas
* if currency = int64, FPC_CURRENCY_IS_INT64 is defined
+ round and trunc for currency and comp if FPC_CURRENCY_IS_INT64 is
defined
* if currency = orddef, prefer currency -> int64/qword conversion over
currency -> float conversions
* optimized currency/currency if currency = orddef
* TODO: write FPC_DIV_CURRENCY and FPC_MUL_CURRENCY routines to prevent
precision loss if currency=int64 and bestreal = double
Revision 1.16 2003/12/08 19:44:11 jonas
* use HandleError instead of RunError so exception catching works
Revision 1.15 2003/09/03 14:09:37 florian
* arm fixes to the common rtl code
* some generic math code fixed
* ...
Revision 1.14 2003/05/24 13:39:32 jonas
* fsqrt is an optional instruction in the ppc architecture and isn't
implemented by any current ppc afaik, so use the generic sqrt routine
instead (adapted so it works with compilerproc)
Revision 1.13 2003/05/23 22:58:31 jonas
* added longint typecase to odd(smallint_var) call to avoid overload
problem
Revision 1.12 2003/05/02 15:12:19 jonas
- removed empty ppc-specific frac()
+ added correct generic frac() implementation for doubles (translated
from glibc code)
Revision 1.11 2003/04/23 21:28:21 peter
* fpc_round added, needed for int64 currency
Revision 1.10 2003/01/15 00:45:17 peter
* use generic int64 power
Revision 1.9 2002/10/12 20:28:49 carl
* round returns int64
Revision 1.8 2002/10/07 15:15:02 florian
* fixed wrong commit
Revision 1.7 2002/10/07 15:10:45 florian
+ variant wrappers for cmp operators added
Revision 1.6 2002/09/07 15:07:45 peter
* old logs removed and tabs fixed
Revision 1.5 2002/07/28 21:39:29 florian
* made abs a compiler proc if it is generic
Revision 1.4 2002/07/28 20:43:48 florian
* several fixes for linux/powerpc
* several fixes to MT
}