Copyright (C) 2002 Mike Sebastian
### Computing the Forensics Algorithm in Radians

Some calculators and early computers only compute trigonometric functions in radians. This
can be a problem if your are wanting to produce a forensics result, since the forensics
algorithm is defined in terms of degrees. However, this is not really an insurmountable
problem. When the calculator or computer only computes in radians, the solution is to insert
the appropriate degrees-to-radians or radians-to-degrees conversion before or after each
step in the algorithm.

So, you might end up computing the forensics algorithm with a key sequence like this on a
hypothetical calculator with angular conversion functions:

9

D->R
(degrees to radians, or displayed value × p ÷ 180)

SIN

D->R

COS

D->R

TAN

ARCTAN

R->D
(radians to degrees, or displayed value × 180 ÷ p)

ARCCOS

R->D

ARCSIN

R->D

Or, on a computer, you might utilize a code snippet similar to the following (all variables
and functions are assumed to be of a suitable extended precision floating point type):

PI = 3.14159265358979323846264;

DR = PI/180.0; "degrees to radians"

RD = 180.0/PI; "radians to degrees"

RESULT = RD*ASIN(RD*ACOS(RD*ATAN(TAN(DR*COS(DR*SIN(DR*9.0))))));

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Last updated August 16, 2002