How to detect Infinity values in Scala?
Scala has Double.isNaN for detecting not-a-number but no Double.isInf for detecting (positive or negative) infinity.
Why? I'd like to check whether a parameter is a "real" number (i.e. has a numeric value). Converting it to a string and checking for "inf" or something will do it, but there must be a better way?
Like in C++: http://en.cppreference.com/w/cpp/numeric/math/isinf
Using Scala 2.10
Answer
Scala's Double has an isInfinite method, and Neg/Pos variants:
scala> val a = 22.0
a: Double = 22.0
scala> a.isInfinite
res0: Boolean = false
scala> val b = 2.0/0
b: Double = Infinity
scala> b.isInfinite
res1: Boolean = true
scala> b.isPosInfinity
res4: Boolean = true