File LOG

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*20
/
/
/ROUTINE TO CALCULATE COMMON LOG (BASE 10)
/USES POLYNOMIAL APPROXIMATION
/
LOG,	STORE
	TEM		/X
	SET 3
	0
/CHECK IF X=0
	FAZE
	SKP
	JMP 3		/ERROR RETURN
/
	ADD TEM		/EXPONENT
	ADA I
	-1		/DIV BY 2
	STC EXP
	STC TEM		/CLR EXPONENT
	LOAD
	TEM
	FMUL
	FP2		/1<X<10
/
/CALCULATE X DEPENDENT FACTOR IN 
/POLYNOMIAL APPROXIMATION
/
	STORE
	TEM
	FADD
	SQRT10
	STORE
	XFAC
	LOAD
	TEM
	FSUB
	SQRT10
	FDIV
	XFAC
	STORE
	XFAC
/
/DO POLYNOMIAL APPROXIMATION
/
	LOAD
	C5
	JMP MULT
	FADD
	C3
	JMP MULT
	FADD
	C1
	JMP MULT+2
	FADD
	FHALF
	STORE
	TEM
/
/ADD IN EXPONENT AS MULTIPLE OF LOG 2
	SFLOAT
	EXP
	FMUL
	LOG2		/LOG(10) 2
	FADD
	TEM
	XSK I 3
	JMP 3
/
MULT,	FMUL
	XFAC
	FMUL
	XFAC
	JMP 0
/
/
TEM,	0
	0
	0
XFAC,	0
	0
	0
LOGE,	7776		/.4342945
	3362
	6756
LOG2,	7776		/.3010
	2320
	7126
FP2,	2		/2
	2000
	0
FP10,	4		/10
	2400
	0
FHALF,	0
	2000
	0
C5,	7776		/.2543275
	2021
	5633
C3,	7776		/.2773839
	2160
	1242
C1,	0		/.8690286
	3363
	6125
SQRT10,	2		/SQUARE ROOT 10
	3123		/3.16227766
	0540
EXP,	0
/
/END SUBROUTINE LOG



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