Section: Elementary Functions
y = floor(x)
where x is a multidimensional array of numerical type.  The floor 
function preserves the type of the argument.  So integer arguments 
are not modified, and float arrays return float arrays as 
outputs, and similarly for double arrays.  The floor function 
is not defined for complex types.
floor function applied to various
(numerical) arguments.  For integer arguments, the floor function has
no effect:
--> floor(3) ans = 3 --> floor(-3) ans = -3
Next, we take the floor of a floating point value:
--> floor(3.023) ans = 3 --> floor(-2.341) ans = -3