Scala 3/scala.collection/ArrayOps

ArrayOps

final class ArrayOps[A](xs: Array[A]) extends AnyVal

This class serves as a wrapper for Arrays with many of the operations found in indexed sequences. Where needed, instances of arrays are implicitly converted into this class. There is generally no reason to create an instance explicitly or use an ArrayOps type. It is better to work with plain Array types instead and rely on the implicit conversion to ArrayOps when calling a method (which does not actually allocate an instance of ArrayOps because it is a value class).

Neither Array nor ArrayOps are proper collection types (i.e. they do not extend Iterable or even IterableOnce). mutable.ArraySeq and immutable.ArraySeq serve this purpose.

The difference between this class and ArraySeqs is that calling transformer methods such as filter and map will yield an array, whereas an ArraySeq will remain an ArraySeq.

Type parameters:
A

type of the elements contained in this array.

Companion:
object
Source:
ArrayOps.scala
class AnyVal
trait Matchable
class Any

Value members

Concrete methods

final def ++[B >: A : ClassTag](xs: IterableOnce[B]): Array[B]
final def ++[B >: A : ClassTag](xs: Array[_ <: B]): Array[B]
final def ++:[B >: A : ClassTag](prefix: IterableOnce[B]): Array[B]
final def ++:[B >: A : ClassTag](prefix: Array[_ <: B]): Array[B]
final def +:[B >: A : ClassTag](x: B): Array[B]
final def :+[B >: A : ClassTag](x: B): Array[B]
final def :++[B >: A : ClassTag](suffix: IterableOnce[B]): Array[B]
final def :++[B >: A : ClassTag](suffix: Array[_ <: B]): Array[B]
def appended[B >: A : ClassTag](x: B): Array[B]

A copy of this array with an element appended.

A copy of this array with an element appended.

Source:
ArrayOps.scala
def appendedAll[B >: A : ClassTag](suffix: IterableOnce[B]): Array[B]

A copy of this array with all elements of a collection appended.

A copy of this array with all elements of a collection appended.

Source:
ArrayOps.scala
def appendedAll[B >: A : ClassTag](suffix: Array[_ <: B]): Array[B]

A copy of this array with all elements of an array appended.

A copy of this array with all elements of an array appended.

Source:
ArrayOps.scala
def collect[B : ClassTag](pf: PartialFunction[A, B]): Array[B]

Builds a new array by applying a partial function to all elements of this array on which the function is defined.

Builds a new array by applying a partial function to all elements of this array on which the function is defined.

Type parameters:
B

the element type of the returned array.

Value parameters:
pf

the partial function which filters and maps the array.

Returns:

a new array resulting from applying the given partial function pf to each element on which it is defined and collecting the results. The order of the elements is preserved.

Source:
ArrayOps.scala
def collectFirst[B](f: PartialFunction[A, B]): Option[B]

Finds the first element of the array for which the given partial function is defined, and applies the partial function to it.

Finds the first element of the array for which the given partial function is defined, and applies the partial function to it.

Source:
ArrayOps.scala
def combinations(n: Int): Iterator[Array[A]]

Iterates over combinations.

Iterates over combinations. A _combination_ of length n is a subsequence of the original array, with the elements taken in order. Thus, Array("x", "y") and Array("y", "y") are both length-2 combinations of Array("x", "y", "y"), but Array("y", "x") is not. If there is more than one way to generate the same subsequence, only one will be returned.

For example, Array("x", "y", "y", "y") has three different ways to generate Array("x", "y") depending on whether the first, second, or third "y" is selected. However, since all are identical, only one will be chosen. Which of the three will be taken is an implementation detail that is not defined.

Returns:

An Iterator which traverses the possible n-element combinations of this array.

Example:

Array("a", "b", "b", "b", "c").combinations(2) == Iterator(Array(a, b), Array(a, c), Array(b, b), Array(b, c))
Source:
ArrayOps.scala
final def concat[B >: A : ClassTag](suffix: IterableOnce[B]): Array[B]
final def concat[B >: A : ClassTag](suffix: Array[_ <: B]): Array[B]
def contains(elem: A): Boolean

Tests whether this array contains a given value as an element.

Tests whether this array contains a given value as an element.

Value parameters:
elem

the element to test.

Returns:

true if this array has an element that is equal (as determined by ==) to elem, false otherwise.

Source:
ArrayOps.scala
def copyToArray[B >: A](xs: Array[B]): Int

Copy elements of this array to another array.

Copy elements of this array to another array. Fills the given array xs starting at index 0. Copying will stop once either all the elements of this array have been copied, or the end of the array is reached.

Type parameters:
B

the type of the elements of the array.

Value parameters:
xs

the array to fill.

Source:
ArrayOps.scala
def copyToArray[B >: A](xs: Array[B], start: Int): Int

Copy elements of this array to another array.

Copy elements of this array to another array. Fills the given array xs starting at index start. Copying will stop once either all the elements of this array have been copied, or the end of the array is reached.

Type parameters:
B

the type of the elements of the array.

Value parameters:
start

the starting index within the destination array.

xs

the array to fill.

Source:
ArrayOps.scala
def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int

Copy elements of this array to another array.

Copy elements of this array to another array. Fills the given array xs starting at index start with at most len values. Copying will stop once either all the elements of this array have been copied, or the end of the array is reached, or len elements have been copied.

Type parameters:
B

the type of the elements of the array.

Value parameters:
len

the maximal number of elements to copy.

start

the starting index within the destination array.

xs

the array to fill.

Source:
ArrayOps.scala
def count(p: A => Boolean): Int

Counts the number of elements in this array which satisfy a predicate

Counts the number of elements in this array which satisfy a predicate

Source:
ArrayOps.scala
def diff[B >: A](that: Seq[B]): Array[A]

Computes the multiset difference between this array and another sequence.

Computes the multiset difference between this array and another sequence.

Value parameters:
that

the sequence of elements to remove

Returns:

a new array which contains all elements of this array except some of occurrences of elements that also appear in that. If an element value x appears n times in that, then the first n occurrences of x will not form part of the result, but any following occurrences will.

Source:
ArrayOps.scala
def distinct: Array[A]

Selects all the elements of this array ignoring the duplicates.

Selects all the elements of this array ignoring the duplicates.

Returns:

a new array consisting of all the elements of this array without duplicates.

Source:
ArrayOps.scala
def distinctBy[B](f: A => B): Array[A]

Selects all the elements of this array ignoring the duplicates as determined by == after applying the transforming function f.

Selects all the elements of this array ignoring the duplicates as determined by == after applying the transforming function f.

Type parameters:
B

the type of the elements after being transformed by f

Value parameters:
f

The transforming function whose result is used to determine the uniqueness of each element

Returns:

a new array consisting of all the elements of this array without duplicates.

Source:
ArrayOps.scala
def drop(n: Int): Array[A]

The rest of the array without its n first elements.

The rest of the array without its n first elements.

Source:
ArrayOps.scala
def dropRight(n: Int): Array[A]

The rest of the array without its n last elements.

The rest of the array without its n last elements.

Source:
ArrayOps.scala
def dropWhile(p: A => Boolean): Array[A]

Drops longest prefix of elements that satisfy a predicate.

Drops longest prefix of elements that satisfy a predicate.

Value parameters:
p

The predicate used to test elements.

Returns:

the longest suffix of this array whose first element does not satisfy the predicate p.

Source:
ArrayOps.scala
def endsWith[B >: A](that: Array[B]): Boolean

Tests whether this array ends with the given array.

Tests whether this array ends with the given array.

Value parameters:
that

the array to test

Returns:

true if this array has that as a suffix, false otherwise.

Source:
ArrayOps.scala
def endsWith[B >: A](that: Iterable[B]): Boolean

Tests whether this array ends with the given sequence.

Tests whether this array ends with the given sequence.

Value parameters:
that

the sequence to test

Returns:

true if this array has that as a suffix, false otherwise.

Source:
ArrayOps.scala
def exists(@deprecatedName("f", "2.13.3") p: A => Boolean): Boolean

Tests whether a predicate holds for at least one element of this array.

Tests whether a predicate holds for at least one element of this array.

Value parameters:
p

the predicate used to test elements.

Returns:

true if the given predicate p is satisfied by at least one element of this array, otherwise false

Source:
ArrayOps.scala
def filter(p: A => Boolean): Array[A]

Selects all elements of this array which satisfy a predicate.

Selects all elements of this array which satisfy a predicate.

Value parameters:
p

the predicate used to test elements.

Returns:

a new array consisting of all elements of this array that satisfy the given predicate p.

Source:
ArrayOps.scala
def filterNot(p: A => Boolean): Array[A]

Selects all elements of this array which do not satisfy a predicate.

Selects all elements of this array which do not satisfy a predicate.

Value parameters:
p

the predicate used to test elements.

Returns:

a new array consisting of all elements of this array that do not satisfy the given predicate p.

Source:
ArrayOps.scala
def find(@deprecatedName("f", "2.13.3") p: A => Boolean): Option[A]

Finds the first element of the array satisfying a predicate, if any.

Finds the first element of the array satisfying a predicate, if any.

Value parameters:
p

the predicate used to test elements.

Returns:

an option value containing the first element in the array that satisfies p, or None if none exists.

Source:
ArrayOps.scala
def flatMap[B : ClassTag](f: A => IterableOnce[B]): Array[B]

Builds a new array by applying a function to all elements of this array and using the elements of the resulting collections.

Builds a new array by applying a function to all elements of this array and using the elements of the resulting collections.

Type parameters:
B

the element type of the returned array.

Value parameters:
f

the function to apply to each element.

Returns:

a new array resulting from applying the given collection-valued function f to each element of this array and concatenating the results.

Source:
ArrayOps.scala
def flatMap[BS, B](f: A => BS)(implicit asIterable: BS => Iterable[B], m: ClassTag[B]): Array[B]
def flatten[B](implicit asIterable: A => IterableOnce[B], m: ClassTag[B]): Array[B]

Flattens a two-dimensional array by concatenating all its rows into a single array.

Flattens a two-dimensional array by concatenating all its rows into a single array.

Type parameters:
B

Type of row elements.

Value parameters:
asIterable

A function that converts elements of this array to rows - Iterables of type B.

Returns:

An array obtained by concatenating rows of this array.

Source:
ArrayOps.scala
def fold[A1 >: A](z: A1)(op: (A1, A1) => A1): A1

Folds the elements of this array using the specified associative binary operator.

Folds the elements of this array using the specified associative binary operator.

Type parameters:
A1

a type parameter for the binary operator, a supertype of A.

Value parameters:
op

a binary operator that must be associative.

z

a neutral element for the fold operation; may be added to the result an arbitrary number of times, and must not change the result (e.g., Nil for list concatenation, 0 for addition, or 1 for multiplication).

Returns:

the result of applying the fold operator op between all the elements, or z if this array is empty.

Source:
ArrayOps.scala
def foldLeft[B](z: B)(op: (B, A) => B): B

Applies a binary operator to a start value and all elements of this array, going left to right.

Applies a binary operator to a start value and all elements of this array, going left to right.

Type parameters:
B

the result type of the binary operator.

Value parameters:
op

the binary operator.

z

the start value.

Returns:

the result of inserting op between consecutive elements of this array, going left to right with the start value z on the left:

op(...op(z, x_1), x_2, ..., x_n)

where x1, ..., xn are the elements of this array. Returns z if this array is empty.

Source:
ArrayOps.scala
def foldRight[B](z: B)(op: (A, B) => B): B

Applies a binary operator to all elements of this array and a start value, going right to left.

Applies a binary operator to all elements of this array and a start value, going right to left.

Type parameters:
B

the result type of the binary operator.

Value parameters:
op

the binary operator.

z

the start value.

Returns:

the result of inserting op between consecutive elements of this array, going right to left with the start value z on the right:

op(x_1, op(x_2, ... op(x_n, z)...))

where x1, ..., xn are the elements of this array. Returns z if this array is empty.

Source:
ArrayOps.scala
def forall(@deprecatedName("f", "2.13.3") p: A => Boolean): Boolean

Tests whether a predicate holds for all elements of this array.

Tests whether a predicate holds for all elements of this array.

Value parameters:
p

the predicate used to test elements.

Returns:

true if this array is empty or the given predicate p holds for all elements of this array, otherwise false.

Source:
ArrayOps.scala
def foreach[U](f: A => U): Unit

Apply f to each element for its side effects.

Apply f to each element for its side effects. Note: [U] parameter needed to help scalac's type inference.

Source:
ArrayOps.scala
def groupBy[K](f: A => K): Map[K, Array[A]]

Partitions this array into a map of arrays according to some discriminator function.

Partitions this array into a map of arrays according to some discriminator function.

Type parameters:
K

the type of keys returned by the discriminator function.

Value parameters:
f

the discriminator function.

Returns:

A map from keys to arrays such that the following invariant holds:

(xs groupBy f)(k) = xs filter (x => f(x) == k)

That is, every key k is bound to an array of those elements x for which f(x) equals k.

Source:
ArrayOps.scala
def groupMap[K, B : ClassTag](key: A => K)(f: A => B): Map[K, Array[B]]

Partitions this array into a map of arrays according to a discriminator function key.

Partitions this array into a map of arrays according to a discriminator function key. Each element in a group is transformed into a value of type B using the value function.

It is equivalent to groupBy(key).mapValues(_.map(f)), but more efficient.

case class User(name: String, age: Int)

def namesByAge(users: Array[User]): Map[Int, Array[String]] =
  users.groupMap(_.age)(_.name)
Type parameters:
B

the type of values returned by the transformation function

K

the type of keys returned by the discriminator function

Value parameters:
f

the element transformation function

key

the discriminator function

Source:
ArrayOps.scala
def grouped(size: Int): Iterator[Array[A]]

Partitions elements in fixed size arrays.

Partitions elements in fixed size arrays.

Value parameters:
size

the number of elements per group

Returns:

An iterator producing arrays of size size, except the last will be less than size size if the elements don't divide evenly.

See also:
Source:
ArrayOps.scala
def head: A

Selects the first element of this array.

Selects the first element of this array.

Returns:

the first element of this array.

Throws:
NoSuchElementException

if the array is empty.

Source:
ArrayOps.scala
def headOption: Option[A]

Optionally selects the first element.

Optionally selects the first element.

Returns:

the first element of this array if it is nonempty, None if it is empty.

Source:
ArrayOps.scala
def indexOf(elem: A, from: Int): Int

Finds index of first occurrence of some value in this array after or at some start index.

Finds index of first occurrence of some value in this array after or at some start index.

Value parameters:
elem

the element value to search for.

from

the start index

Returns:

the index >= from of the first element of this array that is equal (as determined by ==) to elem, or -1, if none exists.

Source:
ArrayOps.scala
def indexWhere(@deprecatedName("f", "2.13.3") p: A => Boolean, from: Int): Int

Finds index of the first element satisfying some predicate after or at some start index.

Finds index of the first element satisfying some predicate after or at some start index.

Value parameters:
from

the start index

p

the predicate used to test elements.

Returns:

the index >= from of the first element of this array that satisfies the predicate p, or -1, if none exists.

Source:
ArrayOps.scala
def indices: Range

Produces the range of all indices of this sequence.

Produces the range of all indices of this sequence.

Returns:

a Range value from 0 to one less than the length of this array.

Source:
ArrayOps.scala
def init: Array[A]

The initial part of the array without its last element.

The initial part of the array without its last element.

Source:
ArrayOps.scala
def inits: Iterator[Array[A]]

Iterates over the inits of this array.

Iterates over the inits of this array. The first value will be this array and the final one will be an empty array, with the intervening values the results of successive applications of init.

Returns:

an iterator over all the inits of this array

Source:
ArrayOps.scala
def intersect[B >: A](that: Seq[B]): Array[A]

Computes the multiset intersection between this array and another sequence.

Computes the multiset intersection between this array and another sequence.

Value parameters:
that

the sequence of elements to intersect with.

Returns:

a new array which contains all elements of this array which also appear in that. If an element value x appears n times in that, then the first n occurrences of x will be retained in the result, but any following occurrences will be omitted.

Source:
ArrayOps.scala
def isEmpty: Boolean

Tests whether the array is empty.

Tests whether the array is empty.

Returns:

true if the array contains no elements, false otherwise.

Source:
ArrayOps.scala
def knownSize: Int

The size of this array.

The size of this array.

Returns:

the number of elements in this array.

Source:
ArrayOps.scala
def last: A

Selects the last element.

Selects the last element.

Returns:

The last element of this array.

Throws:
NoSuchElementException

If the array is empty.

Source:
ArrayOps.scala
def lastIndexOf(elem: A, end: Int): Int

Finds index of last occurrence of some value in this array before or at a given end index.

Finds index of last occurrence of some value in this array before or at a given end index.

Value parameters:
elem

the element value to search for.

end

the end index.

Returns:

the index <= end of the last element of this array that is equal (as determined by ==) to elem, or -1, if none exists.

Source:
ArrayOps.scala
def lastIndexWhere(p: A => Boolean, end: Int): Int

Finds index of last element satisfying some predicate before or at given end index.

Finds index of last element satisfying some predicate before or at given end index.

Value parameters:
p

the predicate used to test elements.

Returns:

the index <= end of the last element of this array that satisfies the predicate p, or -1, if none exists.

Source:
ArrayOps.scala
def lastOption: Option[A]

Optionally selects the last element.

Optionally selects the last element.

Returns:

the last element of this array$ if it is nonempty, None if it is empty.

Source:
ArrayOps.scala
def lazyZip[B](that: Iterable[B]): LazyZip2[A, B, Array[A]]

Analogous to zip except that the elements in each collection are not consumed until a strict operation is invoked on the returned LazyZip2 decorator.

Analogous to zip except that the elements in each collection are not consumed until a strict operation is invoked on the returned LazyZip2 decorator.

Calls to lazyZip can be chained to support higher arities (up to 4) without incurring the expense of constructing and deconstructing intermediary tuples.

val xs = List(1, 2, 3)
val res = (xs lazyZip xs lazyZip xs lazyZip xs).map((a, b, c, d) => a + b + c + d)
// res == List(4, 8, 12)
Type parameters:
B

the type of the second element in each eventual pair

Value parameters:
that

the iterable providing the second element of each eventual pair

Returns:

a decorator LazyZip2 that allows strict operations to be performed on the lazily evaluated pairs or chained calls to lazyZip. Implicit conversion to Iterable[(A, B)] is also supported.

Source:
ArrayOps.scala
def lengthCompare(len: Int): Int

Compares the length of this array to a test value.

Compares the length of this array to a test value.

Value parameters:
len

the test value that gets compared with the length.

Returns:

A value x where

x <  0       if this.length <  len
x == 0       if this.length == len
x >  0       if this.length >  len
Source:
ArrayOps.scala
def lengthIs: Int

Method mirroring SeqOps.lengthIs for consistency, except it returns an Int because length is known and comparison is constant-time.

Method mirroring SeqOps.lengthIs for consistency, except it returns an Int because length is known and comparison is constant-time.

These operations are equivalent to lengthCompare(Int), and allow the following more readable usages:

this.lengthIs < len     // this.lengthCompare(len) < 0
this.lengthIs <= len    // this.lengthCompare(len) <= 0
this.lengthIs == len    // this.lengthCompare(len) == 0
this.lengthIs != len    // this.lengthCompare(len) != 0
this.lengthIs >= len    // this.lengthCompare(len) >= 0
this.lengthIs > len     // this.lengthCompare(len) > 0
Source:
ArrayOps.scala
def map[B](f: A => B)(implicit ct: ClassTag[B]): Array[B]

Builds a new array by applying a function to all elements of this array.

Builds a new array by applying a function to all elements of this array.

Type parameters:
B

the element type of the returned array.

Value parameters:
f

the function to apply to each element.

Returns:

a new array resulting from applying the given function f to each element of this array and collecting the results.

Source:
ArrayOps.scala
def mapInPlace(f: A => A): Array[A]
def nonEmpty: Boolean

Tests whether the array is not empty.

Tests whether the array is not empty.

Returns:

true if the array contains at least one element, false otherwise.

Source:
ArrayOps.scala
def padTo[B >: A : ClassTag](len: Int, elem: B): Array[B]

A copy of this array with an element value appended until a given target length is reached.

A copy of this array with an element value appended until a given target length is reached.

Type parameters:
B

the element type of the returned array.

Value parameters:
elem

the padding value

len

the target length

Returns:

a new array consisting of all elements of this array followed by the minimal number of occurrences of elem so that the resulting collection has a length of at least len.

Source:
ArrayOps.scala
def partition(p: A => Boolean): (Array[A], Array[A])

A pair of, first, all elements that satisfy predicate p and, second, all elements that do not.

A pair of, first, all elements that satisfy predicate p and, second, all elements that do not.

Source:
ArrayOps.scala
def partitionMap[A1 : ClassTag, A2 : ClassTag](f: A => Either[A1, A2]): (Array[A1], Array[A2])

Applies a function f to each element of the array and returns a pair of arrays: the first one made of those values returned by f that were wrapped in scala.util.Left, and the second one made of those wrapped in scala.util.Right.

Applies a function f to each element of the array and returns a pair of arrays: the first one made of those values returned by f that were wrapped in scala.util.Left, and the second one made of those wrapped in scala.util.Right.

Example:

val xs = Array(1, "one", 2, "two", 3, "three") partitionMap {
 case i: Int => Left(i)
 case s: String => Right(s)
}
// xs == (Array(1, 2, 3),
//        Array(one, two, three))
Type parameters:
A1

the element type of the first resulting collection

A2

the element type of the second resulting collection

Value parameters:
f

the 'split function' mapping the elements of this array to an scala.util.Either

Returns:

a pair of arrays: the first one made of those values returned by f that were wrapped in scala.util.Left, and the second one made of those wrapped in scala.util.Right.

Source:
ArrayOps.scala
def patch[B >: A : ClassTag](from: Int, other: IterableOnce[B], replaced: Int): Array[B]

Returns a copy of this array with patched values.

Returns a copy of this array with patched values. Patching at negative indices is the same as patching starting at 0. Patching at indices at or larger than the length of the original array appends the patch to the end. If more values are replaced than actually exist, the excess is ignored.

Value parameters:
from

The start index from which to patch

other

The patch values

replaced

The number of values in the original array that are replaced by the patch.

Source:
ArrayOps.scala
def permutations: Iterator[Array[A]]

Iterates over distinct permutations.

Iterates over distinct permutations.

Returns:

An Iterator which traverses the distinct permutations of this array.

Example:

Array("a", "b", "b").permutations == Iterator(Array(a, b, b), Array(b, a, b), Array(b, b, a))
Source:
ArrayOps.scala
def prepended[B >: A : ClassTag](x: B): Array[B]

A copy of this array with an element prepended.

A copy of this array with an element prepended.

Source:
ArrayOps.scala
def prependedAll[B >: A : ClassTag](prefix: IterableOnce[B]): Array[B]

A copy of this array with all elements of a collection prepended.

A copy of this array with all elements of a collection prepended.

Source:
ArrayOps.scala
def prependedAll[B >: A : ClassTag](prefix: Array[_ <: B]): Array[B]

A copy of this array with all elements of an array prepended.

A copy of this array with all elements of an array prepended.

Source:
ArrayOps.scala
def reverse: Array[A]

Returns a new array with the elements in reversed order.

Returns a new array with the elements in reversed order.

Source:
ArrayOps.scala
def reverseIterator: Iterator[A]

An iterator yielding elements in reversed order.

An iterator yielding elements in reversed order.

Note: xs.reverseIterator is the same as xs.reverse.iterator but implemented more efficiently.

Returns:

an iterator yielding the elements of this array in reversed order

Source:
ArrayOps.scala
def scan[B >: A : ClassTag](z: B)(op: (B, B) => B): Array[B]

Computes a prefix scan of the elements of the array.

Computes a prefix scan of the elements of the array.

Note: The neutral element z may be applied more than once.

Type parameters:
B

element type of the resulting array

Value parameters:
op

the associative operator for the scan

z

neutral element for the operator op

Returns:

a new array containing the prefix scan of the elements in this array

Source:
ArrayOps.scala
def scanLeft[B : ClassTag](z: B)(op: (B, A) => B): Array[B]

Produces an array containing cumulative results of applying the binary operator going left to right.

Produces an array containing cumulative results of applying the binary operator going left to right.

Type parameters:
B

the result type of the binary operator.

Value parameters:
op

the binary operator.

z

the start value.

Returns:

array with intermediate values. Example:

Array(1, 2, 3, 4).scanLeft(0)(_ + _) == Array(0, 1, 3, 6, 10)
Source:
ArrayOps.scala
def scanRight[B : ClassTag](z: B)(op: (A, B) => B): Array[B]

Produces an array containing cumulative results of applying the binary operator going right to left.

Produces an array containing cumulative results of applying the binary operator going right to left.

Type parameters:
B

the result type of the binary operator.

Value parameters:
op

the binary operator.

z

the start value.

Returns:

array with intermediate values. Example:

Array(4, 3, 2, 1).scanRight(0)(_ + _) == Array(10, 6, 3, 1, 0)
Source:
ArrayOps.scala
def size: Int

The size of this array.

The size of this array.

Returns:

the number of elements in this array.

Source:
ArrayOps.scala
def sizeCompare(otherSize: Int): Int

Compares the size of this array to a test value.

Compares the size of this array to a test value.

Value parameters:
otherSize

the test value that gets compared with the size.

Returns:

A value x where

x <  0       if this.size <  otherSize
x == 0       if this.size == otherSize
x >  0       if this.size >  otherSize
Source:
ArrayOps.scala
def sizeIs: Int

Method mirroring SeqOps.sizeIs for consistency, except it returns an Int because size is known and comparison is constant-time.

Method mirroring SeqOps.sizeIs for consistency, except it returns an Int because size is known and comparison is constant-time.

These operations are equivalent to sizeCompare(Int), and allow the following more readable usages:

this.sizeIs < size     // this.sizeCompare(size) < 0
this.sizeIs <= size    // this.sizeCompare(size) <= 0
this.sizeIs == size    // this.sizeCompare(size) == 0
this.sizeIs != size    // this.sizeCompare(size) != 0
this.sizeIs >= size    // this.sizeCompare(size) >= 0
this.sizeIs > size     // this.sizeCompare(size) > 0
Source:
ArrayOps.scala
def slice(from: Int, until: Int): Array[A]

Selects an interval of elements.

Selects an interval of elements. The returned array is made up of all elements x which satisfy the invariant:

from <= indexOf(x) < until
Value parameters:
from

the lowest index to include from this array.

until

the lowest index to EXCLUDE from this array.

Returns:

an array containing the elements greater than or equal to index from extending up to (but not including) index until of this array.

Source:
ArrayOps.scala
def sliding(size: Int, step: Int): Iterator[Array[A]]

Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

Value parameters:
size

the number of elements per group

step

the distance between the first elements of successive groups

Returns:

An iterator producing arrays of size size, except the last element (which may be the only element) will be truncated if there are fewer than size elements remaining to be grouped.

See also:
Source:
ArrayOps.scala
def sortBy[B](f: A => B)(implicit ord: Ordering[B]): Array[A]

Sorts this array according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.

Sorts this array according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.

Type parameters:
B

the target type of the transformation f, and the type where the ordering ord is defined.

Value parameters:
f

the transformation function mapping elements to some other domain B.

ord

the ordering assumed on domain B.

Returns:

an array consisting of the elements of this array sorted according to the ordering where x < y if ord.lt(f(x), f(y)).

See also:
Source:
ArrayOps.scala
def sortWith(lt: (A, A) => Boolean): Array[A]

Sorts this array according to a comparison function.

Sorts this array according to a comparison function.

The sort is stable. That is, elements that are equal (as determined by lt) appear in the same order in the sorted sequence as in the original.

Value parameters:
lt

the comparison function which tests whether its first argument precedes its second argument in the desired ordering.

Returns:

an array consisting of the elements of this array sorted according to the comparison function lt.

Source:
ArrayOps.scala
def sorted[B >: A](implicit ord: Ordering[B]): Array[A]

Sorts this array according to an Ordering.

Sorts this array according to an Ordering.

The sort is stable. That is, elements that are equal (as determined by lt) appear in the same order in the sorted sequence as in the original.

Value parameters:
ord

the ordering to be used to compare elements.

Returns:

an array consisting of the elements of this array sorted according to the ordering ord.

See also:
Source:
ArrayOps.scala
def span(p: A => Boolean): (Array[A], Array[A])

Splits this array into a prefix/suffix pair according to a predicate.

Splits this array into a prefix/suffix pair according to a predicate.

Note: c span p is equivalent to (but more efficient than) (c takeWhile p, c dropWhile p), provided the evaluation of the predicate p does not cause any side-effects.

Value parameters:
p

the test predicate

Returns:

a pair consisting of the longest prefix of this array whose elements all satisfy p, and the rest of this array.

Source:
ArrayOps.scala
def splitAt(n: Int): (Array[A], Array[A])

Splits this array into two at a given position.

Splits this array into two at a given position. Note: c splitAt n is equivalent to (c take n, c drop n).

Value parameters:
n

the position at which to split.

Returns:

a pair of arrays consisting of the first n elements of this array, and the other elements.

Source:
ArrayOps.scala
def startsWith[B >: A](that: Array[B]): Boolean

Tests whether this array starts with the given array.

Tests whether this array starts with the given array.

Source:
ArrayOps.scala
def startsWith[B >: A](that: Array[B], offset: Int): Boolean

Tests whether this array contains the given array at a given index.

Tests whether this array contains the given array at a given index.

Value parameters:
offset

the index where the array is searched.

that

the array to test

Returns:

true if the array that is contained in this array at index offset, otherwise false.

Source:
ArrayOps.scala
def startsWith[B >: A](that: IterableOnce[B], offset: Int): Boolean

Tests whether this array contains the given sequence at a given index.

Tests whether this array contains the given sequence at a given index.

Value parameters:
offset

the index where the sequence is searched.

that

the sequence to test

Returns:

true if the sequence that is contained in this array at index offset, otherwise false.

Source:
ArrayOps.scala
def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S & EfficientSplit
def tail: Array[A]

The rest of the array without its first element.

The rest of the array without its first element.

Source:
ArrayOps.scala
def tails: Iterator[Array[A]]

Iterates over the tails of this array.

Iterates over the tails of this array. The first value will be this array and the final one will be an empty array, with the intervening values the results of successive applications of tail.

Returns:

an iterator over all the tails of this array

Source:
ArrayOps.scala
def take(n: Int): Array[A]

An array containing the first n elements of this array.

An array containing the first n elements of this array.

Source:
ArrayOps.scala
def takeRight(n: Int): Array[A]

An array containing the last n elements of this array.

An array containing the last n elements of this array.

Source:
ArrayOps.scala
def takeWhile(p: A => Boolean): Array[A]

Takes longest prefix of elements that satisfy a predicate.

Takes longest prefix of elements that satisfy a predicate.

Value parameters:
p

The predicate used to test elements.

Returns:

the longest prefix of this array whose elements all satisfy the predicate p.

Source:
ArrayOps.scala
def toArray[B >: A : ClassTag]: Array[B]

Create a copy of this array with the specified element type.

Create a copy of this array with the specified element type.

Source:
ArrayOps.scala
final def toSeq: Seq[A]
def transpose[B](implicit asArray: A => Array[B]): Array[Array[B]]

Transposes a two dimensional array.

Transposes a two dimensional array.

Type parameters:
B

Type of row elements.

Value parameters:
asArray

A function that converts elements of this array to rows - arrays of type B.

Returns:

An array obtained by replacing elements of this arrays with rows the represent.

Source:
ArrayOps.scala
def unzip[A1, A2](implicit asPair: A => (A1, A2), ct1: ClassTag[A1], ct2: ClassTag[A2]): (Array[A1], Array[A2])

Converts an array of pairs into an array of first elements and an array of second elements.

Converts an array of pairs into an array of first elements and an array of second elements.

Type parameters:
A1

the type of the first half of the element pairs

A2

the type of the second half of the element pairs

Value parameters:
asPair

an implicit conversion which asserts that the element type of this Array is a pair.

ct1

a class tag for A1 type parameter that is required to create an instance of Array[A1]

ct2

a class tag for A2 type parameter that is required to create an instance of Array[A2]

Returns:

a pair of Arrays, containing, respectively, the first and second half of each element pair of this Array.

Source:
ArrayOps.scala
def unzip3[A1, A2, A3](implicit asTriple: A => (A1, A2, A3), ct1: ClassTag[A1], ct2: ClassTag[A2], ct3: ClassTag[A3]): (Array[A1], Array[A2], Array[A3])

Converts an array of triples into three arrays, one containing the elements from each position of the triple.

Converts an array of triples into three arrays, one containing the elements from each position of the triple.

Type parameters:
A1

the type of the first of three elements in the triple

A2

the type of the second of three elements in the triple

A3

the type of the third of three elements in the triple

Value parameters:
asTriple

an implicit conversion which asserts that the element type of this Array is a triple.

ct1

a class tag for T1 type parameter that is required to create an instance of Array[T1]

ct2

a class tag for T2 type parameter that is required to create an instance of Array[T2]

ct3

a class tag for T3 type parameter that is required to create an instance of Array[T3]

Returns:

a triple of Arrays, containing, respectively, the first, second, and third elements from each element triple of this Array.

Source:
ArrayOps.scala
def updated[B >: A : ClassTag](index: Int, elem: B): Array[B]

A copy of this array with one single replaced element.

A copy of this array with one single replaced element.

Value parameters:
elem

the replacing element

index

the position of the replacement

Returns:

a new array which is a copy of this array with the element at position index replaced by elem.

Throws:
IndexOutOfBoundsException

if index does not satisfy 0 <= index < length.

Source:
ArrayOps.scala
def withFilter(p: A => Boolean): WithFilter[A]

Creates a non-strict filter of this array.

Creates a non-strict filter of this array.

Note: the difference between c filter p and c withFilter p is that the former creates a new array, whereas the latter only restricts the domain of subsequent map, flatMap, foreach, and withFilter operations.

Value parameters:
p

the predicate used to test elements.

Returns:

an object of class ArrayOps.WithFilter, which supports map, flatMap, foreach, and withFilter operations. All these operations apply to those elements of this array which satisfy the predicate p.

Source:
ArrayOps.scala
def zip[B](that: IterableOnce[B]): Array[(A, B)]

Returns an array formed from this array and another iterable collection by combining corresponding elements in pairs.

Returns an array formed from this array and another iterable collection by combining corresponding elements in pairs. If one of the two collections is longer than the other, its remaining elements are ignored.

Type parameters:
B

the type of the second half of the returned pairs

Value parameters:
that

The iterable providing the second half of each result pair

Returns:

a new array containing pairs consisting of corresponding elements of this array and that. The length of the returned array is the minimum of the lengths of this array and that.

Source:
ArrayOps.scala
def zipAll[A1 >: A, B](that: Iterable[B], thisElem: A1, thatElem: B): Array[(A1, B)]

Returns an array formed from this array and another iterable collection by combining corresponding elements in pairs.

Returns an array formed from this array and another iterable collection by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.

Value parameters:
that

the iterable providing the second half of each result pair

thatElem

the element to be used to fill up the result if that is shorter than this array.

thisElem

the element to be used to fill up the result if this array is shorter than that.

Returns:

a new array containing pairs consisting of corresponding elements of this array and that. The length of the returned array is the maximum of the lengths of this array and that. If this array is shorter than that, thisElem values are used to pad the result. If that is shorter than this array, thatElem values are used to pad the result.

Source:
ArrayOps.scala
def zipWithIndex: Array[(A, Int)]

Zips this array with its indices.

Zips this array with its indices.

Returns:

A new array containing pairs consisting of all elements of this array paired with their index. Indices start at 0.

Source:
ArrayOps.scala