Unlimited intervals
If at least one of the two interval limits is plus or minus infinite, it is an example of an unlimited interval.
As the infinity character is rather difficult to produce using the keyboard, infinite interval limits are expressed in LF‑ET by Inf (for Infinite, Infinity):
‑Inf |
negatively infinite, for the lower interval limit |
Inf |
positively infinite, for the upper interval limit |
Infinite interval limits are always exclusive |
|
|---|---|
] -Inf : … |
ok |
[ -Inf : … |
wrong |
… : Inf [ |
ok |
… : Inf ] |
wrong |