0000043: truncnormal() sometimes returns INFINITY

Notes
(0000167) stkrause (reporter) 2009-08-27 13:00	This bug still affects the current release. It does not only affect truncnormal(), but all other functions that call log(genk_dblrand()). Additionally, (trunc)normal can return NaN if it is called with a deviation parameter of 0. This can really break results in a simulation in unpredictable ways. A possible fix would be to create a gend_dblrand_nonzero() (the random number generators already support this, it is just not easily accessible from outside) and use it instead of genk_dblrand in those functions.

(0000193) rhornig (administrator) 2009-11-09 18:38	A similar issue is occurring with the exponential distribution returning INF if the provided argument is 0 or very small. Generally we should not return INF. the call that led to a Inf value was actually exponential(1/(1770E6))

(0000243) andras (administrator) 2010-04-23 18:49	Affected distributions: normal(), truncnormal(), exponential(), geometric(). Actually, internally we should have used uniform variables on (0,1] not [0,1). Resolved by replacing dblrand() with 1.0-dblrand(). Other distributions containing log() seem to be correct (already contain 1-U). This fix will change simulation fingerprints!

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