Module `Dataframe.Column`

type ('elt, 'storage) t

('elt, 'storage) t represents a column which elements have typed 'elt and the whole data is stored using type 'storage.

Column Creation

val create : ('a, 'b) Array_intf.t -> 'a -> len:int -> ('a, 'b) t

create array_intf elt ~len creates a new column of length len using the storage described in Array_intf. All the elements of the column are initially set to elt.

val of_data : ('a, 'b) Array_intf.t -> 'b -> ('a, 'b) t

of_data array_intf data returns a new column using data as storage.

val of_array : ('a, 'b) Array_intf.t -> 'a array -> ('a, 'b) t

of_array array_intf array creates a new column using data from array. This column is backed by a storage defined in array_intf.

val copy : ?filter:Dataframe__.Bool_array.t -> ('a, 'b) t -> ('a, 'b) t

copy ?filter t returns a new column obtained by copying t. If filter is provided only elements that match filter are copied resulting in a column with potentially less elements than t.

val select : ('a, 'b) t -> indexes:int array -> ('a, 'b) t

select t ~indexes returns a new column using the same storage as t. The elements of this new column are obtained by taking values from t at the indexes specified in indexes. The same index can be specified multiple times in indexes.

Accessors

val mod_ : ('a, 'b) t -> ('a, 'b) Array_intf.t

val get : ('a, _) t -> int -> 'a

get t index returns the element of t stored at the specified index. If index is negative or greater than or equal to the number of elements in t an error is raised.

val set : ('a, _) t -> int -> 'a -> unit

set t index value sets the element of t at index index to the specified value.

val length : (_, _) t -> int

length t returns the number of elements stored in column t.

val elt_name : (_, _) t -> string

elt_name t returns the kind of elements stored in t as a string.

Pretty Printing

val get_string : (_, _) t -> int -> string

get_string t index returns a pretty-print of the element at the specified index in t.

val to_string : 
  ?max_rows:int ->
  ?filter:Dataframe__.Bool_array.t ->
  (_, _) t ->
  string

to_string t returns a multi-line version of elements stored in t. The number of printed elements can be specified via max_rows and an optional filter can be applied.

val fold : ('a, _) t -> init:'b -> f:('b -> 'a -> 'b) -> 'b

val min : ('a, _) t -> 'a option

val max : ('a, _) t -> 'a option

Operating on Packed Values

type packed =

| P : (_, _) t -> packed

The packed type is used to abstract the type of elements and the storage used by a column.

Extracting Type Columns

val extract : packed -> ('a, 'b) Array_intf.t -> ('a, 'b) t option

val extract_exn : packed -> ('a, 'b) Array_intf.t -> ('a, 'b) t

Other Operations

val packed_copy : ?filter:Dataframe__.Bool_array.t -> packed -> packed

val packed_length : packed -> int

val packed_elt_name : packed -> string

val packed_to_string : 
  ?max_rows:int ->
  ?filter:Dataframe__.Bool_array.t ->
  packed ->
  string

val packed_get_string : packed -> int -> string

val packed_select : packed -> indexes:int array -> packed

package dataframe

Module Dataframe.Column