Module `Talon_csv`

CSV codec for Talon dataframes.

  (* From string *)
  let df = Talon_csv.of_string csv_text

  (* From file (streaming) *)
  let df =
    Talon_csv.read "data.csv"
      (* To file (streaming) *)
      Talon_csv.write "out.csv" df

type dtype_spec =
  (string * [ `Float32 | `Float64 | `Int32 | `Int64 | `Bool | `String ]) list

Column type specifications. Columns not listed are auto-detected.

val of_string : 
  ?sep:char ->
  ?names:string list ->
  ?na_values:string list ->
  ?dtype_spec:dtype_spec ->
  string ->
  Talon.t

of_string s parses CSV text into a dataframe. The first row is used as column names unless names is provided, in which case all rows are treated as data.

parameter sep
delimiter character (default ',')

parameter names
explicit column names; when given, all rows are data

parameter na_values
strings treated as null (default [""; "NA"; "N/A"; "null"; "NULL"; "nan"; "NaN"])

parameter dtype_spec
explicit column types; unspecified columns are auto-detected

val to_string : ?sep:char -> ?na_repr:string -> Talon.t -> string

to_string df serializes a dataframe to CSV text. The first row of the output is the column names.

parameter sep
delimiter character (default ',')

parameter na_repr
string for null values (default "")

val read : 
  ?sep:char ->
  ?names:string list ->
  ?na_values:string list ->
  ?dtype_spec:dtype_spec ->
  string ->
  Talon.t

read path reads a CSV file into a dataframe, streaming line by line.

parameter sep
delimiter character (default ',')

parameter names
explicit column names; when given, all rows are data

parameter na_values
strings treated as null

parameter dtype_spec
explicit column types

val write : ?sep:char -> ?na_repr:string -> string -> Talon.t -> unit

write path df writes a dataframe to a CSV file, streaming row by row.

parameter sep
delimiter character (default ',')

parameter na_repr
string for null values (default "")