Definitions on Arrays

This file contains various definitions on Array. It does not contain proofs about these definitions, those are contained in other files in Std.Data.Array.

def Array.range (n : Nat) : Array Nat

The array #[0, 1, ..., n - 1].

def Array.reduceOption {α : Type u_1} (l : Array (Option α)) : Array α

Drop nones from a Array, and replace each remaining some a with a.

def Array.flatten {α : Type u_1} (arr : Array (Array α)) : Array α

Turns #[#[a₁, a₂, ⋯], #[b₁, b₂, ⋯], ⋯] into #[a₁, a₂, ⋯, b₁, b₂, ⋯]

def Array.zipWithIndex {α : Type u_1} (arr : Array α) : Array (α × Nat)

Turns #[a, b] into #[(a, 0), (b, 1)].

def Array.equalSet {α : Type u_1} [BEq α] (xs : Array α) (ys : Array α) : Bool

Check whether xs and ys are equal as sets, i.e. they contain the same elements when disregarding order and duplicates. O(n*m)! If your element type has an Ord instance, it is asymptotically more efficient to sort the two arrays, remove duplicates and then compare them elementwise.

def Array.qsortOrd {α : Type u_1} [ord : Ord α] (xs : Array α) : Array α

Sort an array using compare to compare elements.

@[inline]

def Array.minD {α : Type u_1} [ord : Ord α] (xs : Array α) (d : α) (start : optParam Nat 0) (stop : optParam Nat (Array.size xs)) : α

Find the first minimal element of an array. If the array is empty, d is returned. If start and stop are given, only the subarray xs[start:stop] is considered.

@[inline]

def Array.min? {α : Type u_1} [ord : Ord α] (xs : Array α) (start : optParam Nat 0) (stop : optParam Nat (Array.size xs)) : Option α

Find the first minimal element of an array. If the array is empty, none is returned. If start and stop are given, only the subarray xs[start:stop] is considered.

@[inline]

def Array.minI {α : Type u_1} [ord : Ord α] [Inhabited α] (xs : Array α) (start : optParam Nat 0) (stop : optParam Nat (Array.size xs)) : α

Find the first minimal element of an array. If the array is empty, default is returned. If start and stop are given, only the subarray xs[start:stop] is considered.

@[inline]

def Array.maxD {α : Type u_1} [ord : Ord α] (xs : Array α) (d : α) (start : optParam Nat 0) (stop : optParam Nat (Array.size xs)) : α

Find the first maximal element of an array. If the array is empty, d is returned. If start and stop are given, only the subarray xs[start:stop] is considered.

@[inline]

def Array.max? {α : Type u_1} [ord : Ord α] (xs : Array α) (start : optParam Nat 0) (stop : optParam Nat (Array.size xs)) : Option α

Find the first maximal element of an array. If the array is empty, none is returned. If start and stop are given, only the subarray xs[start:stop] is considered.

@[inline]

def Array.maxI {α : Type u_1} [ord : Ord α] [Inhabited α] (xs : Array α) (start : optParam Nat 0) (stop : optParam Nat (Array.size xs)) : α

Find the first maximal element of an array. If the array is empty, default is returned. If start and stop are given, only the subarray xs[start:stop] is considered.

def Subarray.empty {α : Type u_1} : Subarray α

The empty subarray.

instance Subarray.instEmptyCollectionSubarray {α : Type u_1} : EmptyCollection (Subarray α)

instance Subarray.instInhabitedSubarray {α : Type u_1} : Inhabited (Subarray α)

@[inline]

def Subarray.isEmpty {α : Type u_1} (as : Subarray α) : Bool

Check whether a subarray is empty.

@[inline]

def Subarray.contains {α : Type u_1} [BEq α] (as : Subarray α) (a : α) : Bool

Check whether a subarray contains an element.

def Subarray.popHead? {α : Type u_1} (as : Subarray α) : Option (α × Subarray α)

Remove the first element of a subarray. Returns the element and the remaining subarray, or none if the subarray is empty.