Math functions

EASI has a number of intrinsic mathematical functions. They return a numeric value and operate in double precision.

FUNCTION	TYPE	Description	ARGUMENT	RESULT
SIN	N	sine	radians
COS	N	cosine	radians
TAN	N	tangent	radians
ASIN	N	inverse sine	note 1	radians
ACOS	N	inverse cosine	note 1	radians
ATAN	N	inverse tangent		radians
LN	N	natural logarithm	note 2
LOG10	N	base 10 logarithm	note 2
F$EXP	N	natural exponent
EXP10	N	base 10 exponent
RAD	N	convert degrees to radians	degrees	radians
DEG	N	convert radians to degrees	radians	degrees
ABS	N	absolute value
INT	N	integer part of value
FRAC	N	fractional part of value
MOD	N	modulus	note 3
FLOOR	N	largest integer smaller than value
CEILING	N	smallest integer larger than value
ROUND	N	nearest integer to value
MIN	N	smallest value in list	note 4
MAX	N	largest value in list	note 4

Notes:

magnitude of the argument must not be greater than 1
argument must be greater than 0
compute modulus of first argument relative to second argument
takes any number of Arguments from 1 to 128

Previous versions of EASI required all mathematical functions to be prepended with F$ (for example, F$TAN). This notation is still accepted, but not encouraged. All of the functions listed above will also work in modeling expressions, except for MIN and MAX.

Example

print "Tangent of 45 degrees = ", TAN(RAD(45))

Other Computational Functions

The following lists other computational functions:

GCPPolyTransform()

GCPPolyTransform() is used to apply a polynomial transformation to points based on the supplied GCPs.

Random()

Random() is used to return a random number between 0.0 and 1.0.

Reproject()

Reproject() is used to translate one or more points between two projections defined via GeoInfo structures.