inf(I) : range -> constantinf(x) : constant -> constant
Parameters:
I is an interval.
x is a real number.
Description:
Returns the lower bound of the interval I. Each bound of an interval has its
own precision, so this command is exact, even if the current precision is too
small to represent the bound.
When called on a real number x, inf considers it as an interval formed
of a single point: [x, x]. In other words, inf behaves like the identity.