A collection of rows in a data table.
SDKs
- macOS 10.14+
- Xcode 10.0+
Framework
- Create ML
Declaration
struct Rows
StructureMLData
MLData
Topics
Inspecting a Row Collection
var isA Boolean value indicating whether the collection is empty.
var count: IntThe number of elements in the collection.
Accessing Rows
var first: MLDataThe first element of the collection.
var last: MLDataThe last element of the collection.
func randomReturns a random element of the collection.
func randomReturns a random element of the collection, using the given generator as a source for randomness.
subscript(Range<Int>) -> Slice<MLDataAccesses a contiguous subrange of the collection’s elements.
subscript<R>(R) -> Slice<MLDataAccesses the contiguous subrange of the collection’s elements specified by a range expression.
Finding Rows
func contains(MLDataReturns a Boolean value indicating whether the sequence contains the given element.
func contains(where: (MLDataReturns a Boolean value indicating whether the sequence contains an element that satisfies the given predicate.
func allReturns a Boolean value indicating whether every element of a sequence satisfies a given predicate.
func first(where: (MLDataReturns the first element of the sequence that satisfies the given predicate.
func firstReturns the first index where the specified value appears in the collection.
func firstReturns the first index in which an element of the collection satisfies the given predicate.
func last(where: (MLDataReturns the last element of the sequence that satisfies the given predicate.
func lastReturns the last index where the specified value appears in the collection.
func lastReturns the index of the last element in the collection that matches the given predicate.
func min(by: (MLDataReturns the minimum element in the sequence, using the given predicate as the comparison between elements.
func max(by: (MLDataReturns the maximum element in the sequence, using the given predicate as the comparison between elements.
Selecting Rows
func filter((MLDataReturns an array containing, in order, the elements of the sequence that satisfy the given predicate.
func prefix(Int) -> Slice<MLDataReturns a subsequence, up to the specified maximum length, containing the initial elements of the collection.
func prefix(through: Int) -> Slice<MLDataReturns a subsequence from the start of the collection through the specified position.
func prefix(upReturns a subsequence from the start of the collection up to, but not including, the specified position.
func prefix(while: (MLDataReturns a subsequence containing the initial elements until predicate returns false and skipping the remaining elements.
func suffix(Int) -> Slice<MLDataReturns a subsequence, up to the given maximum length, containing the final elements of the collection.
func suffix(from: Int) -> Slice<MLDataReturns a subsequence from the specified position to the end of the collection.
Excluding Rows
func dropReturns a subsequence containing all but the given number of initial elements.
func dropReturns a subsequence containing all but the specified number of final elements.
func drop(while: (MLDataReturns a subsequence by skipping elements while predicate returns true and returning the remaining elements.
Transforming a Row Collection
func compactReturns an array containing the non-nil results of calling the given transformation with each element of this sequence.
func reduce<Result>(Result, (Result, MLDataReturns the result of combining the elements of the sequence using the given closure.
var lazy: LazyA sequence containing the same elements as this sequence, but on which some operations, such as map and filter, are implemented lazily.
Iterating Over a Row Collection's Rows
func forCalls the given closure on each element in the sequence in the same order as a for-in loop.
func enumerated() -> EnumeratedReturns a sequence of pairs (n, x), where n represents a consecutive integer starting at zero and x represents an element of the sequence.
func makeReturns an iterator over the elements of the collection.
Reordering a Row Collection's Rows
func sorted(by: (MLDataReturns the elements of the sequence, sorted using the given predicate as the comparison between elements.
func reversed() -> ReversedReturns a view presenting the elements of the collection in reverse order.
func shuffled() -> [MLDataReturns the elements of the sequence, shuffled.
func shuffled<T>(using: inout T) -> [MLDataReturns the elements of the sequence, shuffled using the given generator as a source for randomness.
Splitting and Joining Rows
func split(separator: MLDataReturns the longest possible subsequences of the collection, in order, around elements equal to the given element.
func split(maxReturns the longest possible subsequences of the collection, in order, that don’t contain elements satisfying the given predicate.
func joined<Separator>(separator: Separator) -> JoinedReturns the concatenated elements of this sequence of sequences, inserting the given separator between each element.
Comparing Row Collections
func elementsReturns a Boolean value indicating whether this sequence and another sequence contain the same elements in the same order.
func elementsReturns a Boolean value indicating whether this sequence and another sequence contain equivalent elements in the same order, using the given predicate as the equivalence test.
func starts<PossibleReturns a Boolean value indicating whether the initial elements of the sequence are the same as the elements in another sequence.
func starts<PossibleReturns a Boolean value indicating whether the initial elements of the sequence are equivalent to the elements in another sequence, using the given predicate as the equivalence test.
func lexicographicallyReturns a Boolean value indicating whether the sequence precedes another sequence in a lexicographical (dictionary) ordering, using the given predicate to compare elements.
Manipulating Indices
func index(after: Int) -> IntReturns the position immediately after the given index.
func formReplaces the given index with its successor.
func index(before: Int) -> IntReturns the position immediately after the given index.
func formReplaces the given index with its predecessor.
func index(Int, offsetReturns an index that is the specified distance from the given index.
func formOffsets the given index by the specified distance.
func index(Int, offsetReturns an index that is the specified distance from the given index, unless that distance is beyond a given limiting index.
func formOffsets the given index by the specified distance, or so that it equals the given limiting index.
func distance(from: Int, to: Int) -> IntReturns the distance between two indices.
var indices: Range<Int>The indices that are valid for subscripting the collection, in ascending order.
Describing a Row Collection
Supporting Types
struct MLDataA row of untyped values in a data table.
Instance Properties
var underestimatedA value less than or equal to the number of elements in the collection.
Instance Methods
func difference<C>(from: C) -> CollectionReturns the difference needed to produce this collection’s ordered elements from the given collection.
func difference<C>(from: C, by: (CReturns the difference needed to produce this collection’s ordered elements from the given collection, using the given predicate as an equivalence test.
func flatReturns an array containing the concatenated results of calling the given transformation with each element of this sequence.
func index(of: MLDataReturns the first index where the specified value appears in the collection.
func index(where: (MLDataReturns the first index in which an element of the collection satisfies the given predicate.
func joined() -> FlattenReturns the elements of this sequence of sequences, concatenated.
func map<T>((MLDataReturns an array containing the results of mapping the given closure over the sequence’s elements.
func reduce<Result>(into: Result, (inout Result, MLDataReturns the result of combining the elements of the sequence using the given closure.
func withCall body(p), where p is a pointer to the collection’s contiguous storage. If no such storage exists, it is first created. If the collection does not support an internal representation in a form of contiguous storage, body is not called and nil is returned.
See Also
Getting Information About a Data Table’s Rows
var rows: MLDataThe rows of data in the table.