FisherExactTest
Declaration: 
FisherExactTest (FreqTab: TInt2DArray; var ProbLow, ProbHigh, Prob2Tail: double): integer; 

The function FisherExactTest calculates the probabilities of Fisher's exact test of independence for the 2x2 contingency table FreqTab. The variable parameters ProbLow, ProbHigh and Prob2Tail return the probabilities for the onetailed lower tail, the onetailed upper tail and the twotailed test, respectively.
The function returns the following error codes:
0 ... everything is OK
1 ... frequency table is not a 2x2 table
2 ... frequency table too large (N must be less than 1001)
3 ... frequency table must not contain negative numbers

