object Array extends FallbackArrayBuilding with Serializable
Utility methods for operating on arrays. For example:
val a = Array(1, 2) val b = Array.ofDim[Int](2) val c = Array.concat(a, b)
where the array objects a
, b
and c
have respectively the values
Array(1, 2)
, Array(0, 0)
and Array(1, 2, 0, 0)
.
 Source
 Array.scala
 Version
1.0
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 Array
 Serializable
 Serializable
 FallbackArrayBuilding
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final
def
!=(arg0: Any): Boolean
Test two objects for inequality.
Test two objects for inequality.
 returns
true
if !(this == that), false otherwise.
 Definition Classes
 AnyRef → Any

final
def
##(): Int
Equivalent to
x.hashCode
except for boxed numeric types andnull
.Equivalent to
x.hashCode
except for boxed numeric types andnull
. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. Fornull
returns a hashcode wherenull.hashCode
throws aNullPointerException
. returns
a hash value consistent with ==
 Definition Classes
 AnyRef → Any

final
def
==(arg0: Any): Boolean
The expression
x == that
is equivalent toif (x eq null) that eq null else x.equals(that)
.The expression
x == that
is equivalent toif (x eq null) that eq null else x.equals(that)
. returns
true
if the receiver object is equivalent to the argument;false
otherwise.
 Definition Classes
 AnyRef → Any

def
apply(x: Unit, xs: Unit*): Array[Unit]
Creates an array of
Unit
objects 
def
apply(x: Double, xs: Double*): Array[Double]
Creates an array of
Double
objects 
def
apply(x: Float, xs: Float*): Array[Float]
Creates an array of
Float
objects 
def
apply(x: Long, xs: Long*): Array[Long]
Creates an array of
Long
objects 
def
apply(x: Int, xs: Int*): Array[Int]
Creates an array of
Int
objects 
def
apply(x: Char, xs: Char*): Array[Char]
Creates an array of
Char
objects 
def
apply(x: Short, xs: Short*): Array[Short]
Creates an array of
Short
objects 
def
apply(x: Byte, xs: Byte*): Array[Byte]
Creates an array of
Byte
objects 
def
apply(x: Boolean, xs: Boolean*): Array[Boolean]
Creates an array of
Boolean
objects 
def
apply[T](xs: T*)(implicit arg0: ClassTag[T]): Array[T]
Creates an array with given elements.
Creates an array with given elements.
 xs
the elements to put in the array
 returns
an array containing all elements from xs.

final
def
asInstanceOf[T0]: T0
Cast the receiver object to be of type
T0
.Cast the receiver object to be of type
T0
.Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression
1.asInstanceOf[String]
will throw aClassCastException
at runtime, while the expressionList(1).asInstanceOf[List[String]]
will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type. returns
the receiver object.
 Definition Classes
 Any
 Exceptions thrown
ClassCastException
if the receiver object is not an instance of the erasure of typeT0
.
 implicit def canBuildFrom[T](implicit t: ClassTag[T]): CanBuildFrom[Array[_], T, Array[T]]

def
clone(): AnyRef
Create a copy of the receiver object.

def
concat[T](xss: Array[T]*)(implicit arg0: ClassTag[T]): Array[T]
Concatenates all arrays into a single array.
Concatenates all arrays into a single array.
 xss
the given arrays
 returns
the array created from concatenating
xss

def
copy(src: AnyRef, srcPos: Int, dest: AnyRef, destPos: Int, length: Int): Unit
Copy one array to another.
Copy one array to another. Equivalent to Java's
System.arraycopy(src, srcPos, dest, destPos, length)
, except that this also works for polymorphic and boxed arrays.Note that the passedin
dest
array will be modified by this call. src
the source array.
 srcPos
starting position in the source array.
 dest
destination array.
 destPos
starting position in the destination array.
 length
the number of array elements to be copied.
 See also
java.lang.System#arraycopy

def
empty[T](implicit arg0: ClassTag[T]): Array[T]
Returns an array of length 0
 val emptyBooleanArray: Array[Boolean]
 val emptyByteArray: Array[Byte]
 val emptyCharArray: Array[Char]
 val emptyDoubleArray: Array[Double]
 val emptyFloatArray: Array[Float]
 val emptyIntArray: Array[Int]
 val emptyLongArray: Array[Long]
 val emptyObjectArray: Array[AnyRef]
 val emptyShortArray: Array[Short]

final
def
eq(arg0: AnyRef): Boolean
Tests whether the argument (
that
) is a reference to the receiver object (this
).Tests whether the argument (
that
) is a reference to the receiver object (this
).The
eq
method implements an equivalence relation on nonnull instances ofAnyRef
, and has three additional properties: It is consistent: for any nonnull instances
x
andy
of typeAnyRef
, multiple invocations ofx.eq(y)
consistently returnstrue
or consistently returnsfalse
.  For any nonnull instance
x
of typeAnyRef
,x.eq(null)
andnull.eq(x)
returnsfalse
. null.eq(null)
returnstrue
.
When overriding the
equals
orhashCode
methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2
), they should be equal to each other (o1 == o2
) and they should hash to the same value (o1.hashCode == o2.hashCode
). returns
true
if the argument is a reference to the receiver object;false
otherwise.
 Definition Classes
 AnyRef
 It is consistent: for any nonnull instances

def
equals(arg0: Any): Boolean
The equality method for reference types.

implicit
def
fallbackCanBuildFrom[T](implicit m: DummyImplicit): CanBuildFrom[Array[_], T, ArraySeq[T]]
A builder factory that generates a generic array.
A builder factory that generates a generic array. Called instead of
Array.newBuilder
if the element type of an array does not have a class tag. Note that fallbackBuilder factory needs an implicit parameter (otherwise it would not be dominated in implicit search byArray.canBuildFrom
). We make sure that implicit search is always successful. Definition Classes
 FallbackArrayBuilding

def
fill[T](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(elem: ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[Array[Array[Array[T]]]]]
Returns a fivedimensional array that contains the results of some element computation a number of times.
Returns a fivedimensional array that contains the results of some element computation a number of times.
 n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 n3
the number of elements in the 3nd dimension
 n4
the number of elements in the 4th dimension
 n5
the number of elements in the 5th dimension
 elem
the element computation

def
fill[T](n1: Int, n2: Int, n3: Int, n4: Int)(elem: ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[Array[Array[T]]]]
Returns a fourdimensional array that contains the results of some element computation a number of times.
Returns a fourdimensional array that contains the results of some element computation a number of times.
 n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 n3
the number of elements in the 3nd dimension
 n4
the number of elements in the 4th dimension
 elem
the element computation

def
fill[T](n1: Int, n2: Int, n3: Int)(elem: ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[Array[T]]]
Returns a threedimensional array that contains the results of some element computation a number of times.
Returns a threedimensional array that contains the results of some element computation a number of times.
 n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 n3
the number of elements in the 3nd dimension
 elem
the element computation

def
fill[T](n1: Int, n2: Int)(elem: ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[T]]
Returns a twodimensional array that contains the results of some element computation a number of times.
Returns a twodimensional array that contains the results of some element computation a number of times.
 n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 elem
the element computation

def
fill[T](n: Int)(elem: ⇒ T)(implicit arg0: ClassTag[T]): Array[T]
Returns an array that contains the results of some element computation a number of times.
Returns an array that contains the results of some element computation a number of times.
Note that this means that
elem
is computed a total of n times:scala> Array.fill(3){ math.random } res3: Array[Double] = Array(0.365461167592537, 1.550395944913685E4, 0.7907242137333306)
 n
the number of elements desired
 elem
the element computation
 returns
an Array of size n, where each element contains the result of computing
elem
.

def
finalize(): Unit
Called by the garbage collector on the receiver object when there are no more references to the object.
Called by the garbage collector on the receiver object when there are no more references to the object.
The details of when and if the
finalize
method is invoked, as well as the interaction betweenfinalize
and nonlocal returns and exceptions, are all platform dependent. 
final
def
getClass(): Class[_]
Returns the runtime class representation of the object.
Returns the runtime class representation of the object.
 returns
a class object corresponding to the runtime type of the receiver.
 Definition Classes
 AnyRef → Any

def
hashCode(): Int
The hashCode method for reference types.

final
def
isInstanceOf[T0]: Boolean
Test whether the dynamic type of the receiver object is
T0
.Test whether the dynamic type of the receiver object is
T0
.Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression
1.isInstanceOf[String]
will returnfalse
, while the expressionList(1).isInstanceOf[List[String]]
will returntrue
. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type. returns
true
if the receiver object is an instance of erasure of typeT0
;false
otherwise.
 Definition Classes
 Any

def
iterate[T](start: T, len: Int)(f: (T) ⇒ T)(implicit arg0: ClassTag[T]): Array[T]
Returns an array containing repeated applications of a function to a start value.
Returns an array containing repeated applications of a function to a start value.
 start
the start value of the array
 len
the number of elements returned by the array
 f
the function that is repeatedly applied
 returns
the array returning
len
values in the sequencestart, f(start), f(f(start)), ...

final
def
ne(arg0: AnyRef): Boolean
Equivalent to
!(this eq that)
.Equivalent to
!(this eq that)
. returns
true
if the argument is not a reference to the receiver object;false
otherwise.
 Definition Classes
 AnyRef

def
newBuilder[T](implicit t: ClassTag[T]): ArrayBuilder[T]
Returns a new scala.collection.mutable.ArrayBuilder.

final
def
notify(): Unit
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
 Definition Classes
 AnyRef
 Note
not specified by SLS as a member of AnyRef

final
def
notifyAll(): Unit
Wakes up all threads that are waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
 Definition Classes
 AnyRef
 Note
not specified by SLS as a member of AnyRef

def
ofDim[T](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(implicit arg0: ClassTag[T]): Array[Array[Array[Array[Array[T]]]]]
Creates a 5dimensional array

def
ofDim[T](n1: Int, n2: Int, n3: Int, n4: Int)(implicit arg0: ClassTag[T]): Array[Array[Array[Array[T]]]]
Creates a 4dimensional array

def
ofDim[T](n1: Int, n2: Int, n3: Int)(implicit arg0: ClassTag[T]): Array[Array[Array[T]]]
Creates a 3dimensional array

def
ofDim[T](n1: Int, n2: Int)(implicit arg0: ClassTag[T]): Array[Array[T]]
Creates a 2dimensional array

def
ofDim[T](n1: Int)(implicit arg0: ClassTag[T]): Array[T]
Creates array with given dimensions

def
range(start: Int, end: Int, step: Int): Array[Int]
Returns an array containing equally spaced values in some integer interval.
Returns an array containing equally spaced values in some integer interval.
 start
the start value of the array
 end
the end value of the array, exclusive (in other words, this is the first value not returned)
 step
the increment value of the array (may not be zero)
 returns
the array with values in
start, start + step, ...
up to, but excludingend

def
range(start: Int, end: Int): Array[Int]
Returns an array containing a sequence of increasing integers in a range.
Returns an array containing a sequence of increasing integers in a range.
 start
the start value of the array
 end
the end value of the array, exclusive (in other words, this is the first value not returned)
 returns
the array with values in range
start, start + 1, ..., end  1
up to, but excluding,end
.

final
def
synchronized[T0](arg0: ⇒ T0): T0
 Definition Classes
 AnyRef

def
tabulate[T](n1: Int, n2: Int, n3: Int, n4: Int, n5: Int)(f: (Int, Int, Int, Int, Int) ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[Array[Array[Array[T]]]]]
Returns a fivedimensional array containing values of a given function over ranges of integer values starting from
0
.Returns a fivedimensional array containing values of a given function over ranges of integer values starting from
0
. n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 n3
the number of elements in the 3rd dimension
 n4
the number of elements in the 4th dimension
 n5
the number of elements in the 5th dimension
 f
The function computing element values

def
tabulate[T](n1: Int, n2: Int, n3: Int, n4: Int)(f: (Int, Int, Int, Int) ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[Array[Array[T]]]]
Returns a fourdimensional array containing values of a given function over ranges of integer values starting from
0
.Returns a fourdimensional array containing values of a given function over ranges of integer values starting from
0
. n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 n3
the number of elements in the 3rd dimension
 n4
the number of elements in the 4th dimension
 f
The function computing element values

def
tabulate[T](n1: Int, n2: Int, n3: Int)(f: (Int, Int, Int) ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[Array[T]]]
Returns a threedimensional array containing values of a given function over ranges of integer values starting from
0
.Returns a threedimensional array containing values of a given function over ranges of integer values starting from
0
. n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 n3
the number of elements in the 3rd dimension
 f
The function computing element values

def
tabulate[T](n1: Int, n2: Int)(f: (Int, Int) ⇒ T)(implicit arg0: ClassTag[T]): Array[Array[T]]
Returns a twodimensional array containing values of a given function over ranges of integer values starting from
0
.Returns a twodimensional array containing values of a given function over ranges of integer values starting from
0
. n1
the number of elements in the 1st dimension
 n2
the number of elements in the 2nd dimension
 f
The function computing element values

def
tabulate[T](n: Int)(f: (Int) ⇒ T)(implicit arg0: ClassTag[T]): Array[T]
Returns an array containing values of a given function over a range of integer values starting from 0.
Returns an array containing values of a given function over a range of integer values starting from 0.
 n
The number of elements in the array
 f
The function computing element values
 returns
A traversable consisting of elements
f(0),f(1), ..., f(n  1)

def
toString(): String
Creates a String representation of this object.
Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.
 returns
a String representation of the object.
 Definition Classes
 AnyRef → Any

def
unapplySeq[T](x: Array[T]): Option[IndexedSeq[T]]
Called in a pattern match like
{ case Array(x,y,z) => println('3 elements')}
.Called in a pattern match like
{ case Array(x,y,z) => println('3 elements')}
. x
the selector value
 returns
sequence wrapped in a scala.Some, if
x
is a Seq, otherwiseNone

final
def
wait(): Unit
 Definition Classes
 AnyRef
 Annotations
 @throws( ... )

final
def
wait(arg0: Long, arg1: Int): Unit
 Definition Classes
 AnyRef
 Annotations
 @throws( ... )

final
def
wait(arg0: Long): Unit
 Definition Classes
 AnyRef
 Annotations
 @throws( ... )
This is the documentation for the Scala standard library.
Package structure
The scala package contains core types like
Int
,Float
,Array
orOption
which are accessible in all Scala compilation units without explicit qualification or imports.Notable packages include:
scala.collection
and its subpackages contain Scala's collections frameworkscala.collection.immutable
 Immutable, sequential datastructures such asVector
,List
,Range
,HashMap
orHashSet
scala.collection.mutable
 Mutable, sequential datastructures such asArrayBuffer
,StringBuilder
,HashMap
orHashSet
scala.collection.concurrent
 Mutable, concurrent datastructures such asTrieMap
scala.collection.parallel.immutable
 Immutable, parallel datastructures such asParVector
,ParRange
,ParHashMap
orParHashSet
scala.collection.parallel.mutable
 Mutable, parallel datastructures such asParArray
,ParHashMap
,ParTrieMap
orParHashSet
scala.concurrent
 Primitives for concurrent programming such asFutures
andPromises
scala.io
 Input and output operationsscala.math
 Basic math functions and additional numeric types likeBigInt
andBigDecimal
scala.sys
 Interaction with other processes and the operating systemscala.util.matching
 Regular expressionsOther packages exist. See the complete list on the right.
Additional parts of the standard library are shipped as separate libraries. These include:
scala.reflect
 Scala's reflection API (scalareflect.jar)scala.xml
 XML parsing, manipulation, and serialization (scalaxml.jar)scala.swing
 A convenient wrapper around Java's GUI framework called Swing (scalaswing.jar)scala.util.parsing
 Parser combinators, including an example implementation of a JSON parser (scalaparsercombinators.jar)Automatic imports
Identifiers in the scala package and the
scala.Predef
object are always in scope by default.Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example,
List
is an alias forscala.collection.immutable.List
.Other aliases refer to classes provided by the underlying platform. For example, on the JVM,
String
is an alias forjava.lang.String
.