Header menu logo Deedle

IIndex<'K> Type

An interface that represents index mapping keys of some generic type `T` to locations of address `Address`. The `IIndex` contains minimal set of operations that have to be supported by an index. This type should be only used directly when extending the DataFrame library and adding a new way of storing or loading data. Values of this type are constructed using the associated `IIndexBuilder` type.

Instance members

Instance member Description

this.AddressAt

Full Usage: this.AddressAt

Parameters:
    arg0 : int64

Returns: Address
Modifiers: abstract

Return an address that represents the specified offset

arg0 : int64
Returns: Address

this.AddressOperations

Full Usage: this.AddressOperations

Returns: IAddressOperations
Modifiers: abstract

Returns the address operations associated with this index. The addresses of the index are not necesarilly continuous integers from 0. This provides some operations that can be used for implementing generic operations over any kind of indices.

Returns: IAddressOperations

this.AddressingScheme

Full Usage: this.AddressingScheme

Returns: IAddressingScheme
Modifiers: abstract

Returns the addressing scheme of the index. When creating a series or a frame this is compared for equality with the addressing scheme of the vector(s).

Returns: IAddressingScheme

this.Builder

Full Usage: this.Builder

Returns: IIndexBuilder
Modifiers: abstract

Returns an index builder that can be used for constructing new indices of the same kind as the current index (e.g. a lazy index returns a lazy index builder)

Returns: IIndexBuilder

this.Comparer

Full Usage: this.Comparer

Returns: Comparer<'K>
Modifiers: abstract

Returns a comparer associated with the values used by the current index.

Returns: Comparer<'K>

this.IsEmpty

Full Usage: this.IsEmpty

Returns: bool
Modifiers: abstract

Returns whether the specified index is empty. This is equivalent to testing if `Keys` are empty, but it does not have to evaluate delayed index.

Returns: bool

this.IsOrdered

Full Usage: this.IsOrdered

Returns: bool
Modifiers: abstract

Returns `true` if the index is ordered and `false` otherwise

Returns: bool

this.KeyAt

Full Usage: this.KeyAt

Parameters:
Returns: 'K
Modifiers: abstract

Performs reverse lookup - and returns key for a specified address

arg0 : Address
Returns: 'K

this.KeyCount

Full Usage: this.KeyCount

Returns: int64
Modifiers: abstract

Returns the number of keys in the index

Returns: int64

this.KeyRange

Full Usage: this.KeyRange

Returns: 'K * 'K
Modifiers: abstract

Returns the minimal and maximal key associated with the index. (the operation may fail for unordered indices)

Returns: 'K * 'K

this.KeySequence

Full Usage: this.KeySequence

Returns: 'K seq
Modifiers: abstract

Returns a lazy sequence that iterates over all keys in the index

Returns: 'K seq

this.Keys

Full Usage: this.Keys

Returns: ReadOnlyCollection<'K>
Modifiers: abstract

Returns a (fully evaluated) collection with all keys in the index

Returns: ReadOnlyCollection<'K>

this.Locate

Full Usage: this.Locate

Parameters:
    key : 'K

Returns: Address
Modifiers: abstract
key : 'K
Returns: Address

this.Lookup

Full Usage: this.Lookup

Parameters:
Returns: OptionalValue<'K * Address>
Modifiers: abstract

Find the address associated with the specified key, or with the nearest key as specified by the `lookup` argument. The `condition` function is called when searching for keys to ask the caller whether the address should be returned (or whether to continue searching). This is used when searching for previous element in a series (where we need to check if a value at the address is available)

key : 'K
lookup : Lookup
condition : Address -> bool
Returns: OptionalValue<'K * Address>

this.Mappings

Full Usage: this.Mappings

Returns: KeyValuePair<'K, Address> seq
Modifiers: abstract

Returns all key-address mappings in the index

Returns: KeyValuePair<'K, Address> seq

Type something to start searching.