Apple-2gs-SW/ORCALib
1
0
Fork 0
mirror of https://github.com/byteworksinc/ORCALib.git synced 2025-04-13 07:37:09 +00:00
Code Issues Projects Releases Wiki Activity

Implement asinh().

Browse Source 
This is similar to the approach recommended in Apple Numerics Manual Ch. 9, except that there is an added case for large values that would otherwise cause an overflow or spuriously report underflow.
This commit is contained in:
Stephen Heumann 2021-12-24 15:56:36 -06:00
parent b62940404f
commit 997e430562
2 changed files with 132 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

126
math2.asm
View File

@ -328,6 +328,132 @@ one dc i'1' constants
ln2 dc e'0.69314718055994530942'
end
****************************************************************
*
* double asinh(double x);
*
* Returns the inverse hyperbolic sine of x.
*
****************************************************************
*
asinh start
asinhf entry
asinhl entry
using MathCommon2
csubroutine (10:x),0
phb
phk
plb
pha save env & set to default
tsc
inc a
pea 0
pha
FPROCENTRY
pei x+8 save sign of x
asl x+8 x = abs(x)
lsr x+8
lda x t1 = y = z = x
sta y
sta z
sta t1
lda x+2
sta y+2
sta z+2
sta t1+2
lda x+4
sta y+4
sta z+4
sta t1+4
lda x+6
sta y+6
sta z+6
sta t1+6
lda x+8
sta y+8
sta z+8
sta t1+8
lda x if value is zero (or typical inf)
ora x+2
ora x+4
ora x+6
beq skipcalc return the input value
lda x+8 else if x is very small
cmp #-33+16383
bge calc
pea INEXACT raise "inexact" exception
FSETXCP
skipcalc brl setsign return the input value
calc cmp #16383/2+16383 else if x is very large (or nan)
blt notbig
ph4 #z z = ln(x) + ln(2)
FLNX
ph4 #ln2
ph4 #z
FADDX
brl setsign else
notbig pea -2 t1 = 1 / (t1 * t1)
ph4 #t1
FXPWRI
ph4 #one t1 = 1 + t1
ph4 #t1
FADDI
ph4 #t1 t1 = sqrt(t1)
FSQRTX
pea -1 y = 1 / y
ph4 #y
FXPWRI
ph4 #y t1 = t1 + y
ph4 #t1
FADDX
ph4 #t1 z = z / t1
ph4 #z
FDIVX
tdc z = z + x
clc
adc #x
pea 0
pha
ph4 #z
FADDX
ph4 #z z = ln(1+z)
FLN1X
setsign asl z+8 sign of z = original sign of x
pla
asl a
ror z+8
FPROCEXIT restore env & raise any new exceptions
plb
lda #z return z
sta x
lda #^z
sta x+2
creturn 4:x
y ds 10 temporary variables
z ds 10
one dc i'1' constants
ln2 dc e'0.69314718055994530942'
end
****************************************************************
*
* double atanh(double x);

7
math2.macros
View File

@ -639,4 +639,9 @@
LDX #$090A
JSL $E10000
MEND
MACRO
&LAB FXPWRI
&LAB PEA $0010
LDX #$0B0A
JSL $E10000
MEND