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Array goodies

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There are lots of useful methods for arrays and array buffers. For these methods, check out ArrayOps in the Scala Doc. Let's see some examples:

scala> val a = Array(35, 47, 3, 24, 73, 6, 4)
a: Array[Int] = Array(35, 47, 3, 24, 73, 6, 4)

scala> a.count(_ > 20)                       // How many elems are > 20?
res32: Int = 4

scala> a.filter(_ > 20)                      // Which elems are > 20?
res33: Array[Int] = Array(35, 47, 24, 73) 

scala> a.partition(_ > 20)                   // take elems that satisfy the condition and take elems that don't
res34: (Array[Int], Array[Int]) = (Array(35, 47, 24, 73),Array(3, 6, 4))

scala> a contains 24
res35: Boolean = true

scala> val a = Array(1, 2, 2, 6, 2, 4, 1)
a: Array[Int] = Array(1, 2, 2, 6, 2, 4, 1)

scala> a.distinct                            // remove duplicates
res36: Array[Int] = Array(1, 2, 6, 4)

scala> a
res37: Array[Int] = Array(1, 2, 2, 6, 2, 4, 1)

scala> a.sum
res38: Int = 18

scala> a.product
res39: Int = 192

scala> a.max
res40: Int = 6

scala> a.min
res41: Int = 1

scala> a.reverse
res42: Array[Int] = Array(1, 4, 2, 6, 2, 2, 1)

Convert each element

scala> val a = Array("1", "2", "3")
a: Array[String] = Array(1, 2, 3)

scala> a.map(s => s.toInt)
res10: Array[Int] = Array(1, 2, 3)

// ----- it works with other collections too -----

scala> val b = ArrayBuffer("1", "2", "3")
b: scala.collection.mutable.ArrayBuffer[String] = ArrayBuffer(1, 2, 3)

scala> b.map(s => s.toInt)
res9: scala.collection.mutable.ArrayBuffer[Int] = ArrayBuffer(1, 2, 3)