Atari 400 Basic Reference Manual

Derived Functions
Secant
Cosecant
Inverse Sine
Inverse Cosine
Inverse Secant
Inverse Cosecant
Inverse Cotangent
Hyperbolic Sine
Hyperbolic Cosine
Hyperbolic Tangent
Hyperbolic Secant
Hy
perbolic Cosecant
Hyperbolic Cotangent
Inverse Hyperbolic Sine
Inverse Hyperbolic Cosine
Inverse Hyperbolic Tangent
Inv erse Hy per bolic Sec ant
Inverse Hyperbolic Cosecant
Inverse Hyperbolic Cotangent
Notes:
APPENDIX E
DERIVED
FUNCTIONS
Derived Functions in Terms of Atari Functions
SEC(X)"' 1/COS(X)
CSC(X)"' 1/SIN(X)
ARCSIN(X)
"'A TN(X/SQR( -X* X+ 1))
ARCCOS(X)"'
-A TN(X/SQR(- X* X+ 1) +CONSTANT
ARSEC(X) "'ATN{SQR(X * X-1)) + (SGN(X-1)* CONSTANT
ARCCSC(X) "'A TN(1 /SQR(X * X-1)) + (SGN(X-1) *CONSTANT
ARCCOT(X) "'A TN(X) +CONSTANT
SINH(X)"' (EXP(X)-EXP(-X))/2
COSH(X) "'(EXP(X) + EXP(-X))/2
TANH(X),-EXP(-X)/(EXP{X) +EXP(-X)) *2 + 1
SECH(X) = 2/(EXP(X) + EXP(-
X))
CSCH(X) = 2/(EXP(X)-EXP(-X))
COTH(X) = EXP(-X)/(EXP(X)-EXP(-X)}* 2 + 1
ARCSINH(X)
=LOG( X+ SQR(X *X+ 1 ))
ARCCOSH(X) + LOG(X + SQR(X * X-1))
ARCTANH(X) "'LOG((1 + X)/(1-X))/2
ARCSECH(X) =LOG((SQR(-
X* X+ 1) + 1)/X)
ARCCSCH(X) "'LOG((SGN(X) * SQR(X
*X+ 1) + 1)/X)
ARCCOTH(X) = LOG((X + 1)/(X-1))/2
1. If in RAD (default) mode, constant = 1.57079633
If in DEG mode, constant = 90.
2.
In this chart , the variable X in parentheses represents the value or expression to be evaluated by the
derived function . Obviously, any variable name is permissible, as long as it represents the number or
expression to be evaluated.
App endix E-1

Atari 400 Specifications

General

Manufacturer	Atari
Model	400
Type	Home Computer
Release Year	1979
CPU	MOS Technology 6502
CPU Speed	1.79 MHz
ROM	10 KB
Operating System	Atari OS
Keyboard	Membrane keyboard
RAM	8 KB (expandable to 48 KB)
Graphics	ANTIC and GTIA chips
Sound	4 channels
Display	RF output for connection to TV
Storage	Optional cassette tape drive or floppy disk drive
Ports	Cartridge
Display Resolution	320x192 (16 colors)