id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
431	Problems with logical functions and unknown values	Francisco Muñoz	Víctor de Buen Remiro	"Real Logical operations (And + Or) doenst work rigth with Unknown values
 Real a = Or (?,1) 
Should give you 1 but gives you ?
 Real a = Or (1,?) 
Gives you 1, the right value.
 Real b = And (?,0)
Should give you 0 but gives you ?
 Real b = And (0,?)
Gives you 0, the right value.

 As a rule of thumb if the ""Or"" function should only give you Unknown if all the data are either 0 or (at least one) Unkown. If there is one non-false/non-unnkown value you should get 1.

 The ""And"" function should only give you Unknown if all the data are either 1 or (at least one) Unkwown. If there is one false/non-unnkown value you should get 0.

(Even in the case of ""operations-with-unknown-always-get-unknown-output"" defined TOL should give us a consistent answer no matter the order of the inputs)

Related to Bug 427"	defect	closed	normal		Math	head	normal	fixed