Deedle

FSharpFrameExtensions

Table of contents

Frame operations 

Type extensions

Type extensionDescription
PivotTable(r, c, op)
Signature: (r:'TColumnKey * c:'TColumnKey * op:(Frame<'TRowKey,'TColumnKey> -> 'T)) -> Frame<'R,'C>
Type parameters: 'R, 'C, 'T

Creates a new data frame resulting from a 'pivot' operation. Consider a denormalized data frame representing a table: column labels are field names & table values are observations of those fields. pivotTable buckets the rows along two axes, according to the values of the columns r and c; and then computes a value for the frame of rows that land in each bucket.

Parameters

  • r - A column key to group on for the resulting row index
  • c - A column key to group on for the resulting col index
  • op - A function computing a value from the corresponding bucket frame

Input and output 

Type extensions

Type extensionDescription
SaveCsv(...)
Signature: (writer:TextWriter * includeRowKeys:bool option * keyNames:seq<string> option * separator:char option * culture:CultureInfo option) -> unit

Save data frame to a CSV fileor aTextWriter. When calling the operation, you can specify whether you want to save the row keys or not (and headers for the keys) and you can also specify the separator (use\tfor writing TSV files). When specifying file name ending with.tsv, the\t` separator is used automatically.

Parameters

  • writer - Specifies the TextWriter to which the CSV data should be written
  • includeRowKeys - When set to true, the row key is also written to the output file
  • keyNames - Can be used to specify the CSV headers for row key (or keys, for multi-level index)
  • separator - Specify the column separator in the file (the default is \t for TSV files and , for CSV files)
  • culture - Specify the CultureInfo object used for formatting numerical data
SaveCsv(...)
Signature: (path:string * includeRowKeys:bool option * keyNames:seq<string> option * separator:char option * culture:CultureInfo option) -> unit

Save data frame to a CSV file or a TextWriter. When calling the operation, you can specify whether you want to save the row keys or not (and headers for the keys) and you can also specify the separator (use \t for writing TSV files). When specifying file name ending with .tsv, the \t separator is used automatically.

Parameters

  • path - Specifies the output file name where the CSV data should be written
  • includeRowKeys - When set to true, the row key is also written to the output file
  • keyNames - Can be used to specify the CSV headers for row key (or keys, for multi-level index)
  • separator - Specify the column separator in the file (the default is \t for TSV files and , for CSV files)
  • culture - Specify the CultureInfo object used for formatting numerical data
SaveCsv(path, keyNames)
Signature: (path:string * keyNames:seq<string>) -> unit

Save data frame to a CSV file or to a TextWriter. When calling the operation, you can specify whether you want to save the row keys or not (and headers for the keys) and you can also specify the separator (use \t for writing TSV files). When specifying file name ending with .tsv, the \t separator is used automatically.

Parameters

  • path - Specifies the output file name where the CSV data should be written
  • keyNames - Specifies the CSV headers for row key (or keys, for multi-level index)
  • separator - Specify the column separator in the file (the default is \t for TSV files and , for CSV files)
  • culture - Specify the CultureInfo object used for formatting numerical data

Other module members 

Functions and values

Function or valueDescription
( =?> ) a b
Signature: a:'?468901 -> b:ISeries<'?468902> -> '?468901 * ISeries<'?468902>
Type parameters: '?468901, '?468902

Custom operator that can be used when constructing a frame from observations of series. The operator simply returns a tuple, but it upcasts the series argument so you don't have to do manual casting. For example:

frame [ "k1" =?> series [0 => "a"]; "k2" =?> series ["x" => "y"] ]
( => ) a b
Signature: a:'?468898 -> b:'?468899 -> '?468898 * '?468899
Type parameters: '?468898, '?468899

Custom operator that can be used when constructing series from observations or frames from key-row or key-column pairs. The operator simply returns a tuple, but it provides a more convenient syntax. For example:

series [ "k1" => 1; "k2" => 15 ]
frame columns
Signature: columns:seq<'?468904 * '?468905> -> Frame<'?468906,'?468904>
Type parameters: '?468904, '?468905, '?468906

A function for constructing data frame from a sequence of name - column pairs. This provides a nicer syntactic sugar for Frame.ofColumns.

Example

To create a simple frame with two columns, you can write:

frame [ "A" => series [ 1 => 30.0; 2 => 35.0 ]
        "B" => series [ 1 => 30.0; 3 => 40.0 ] ]

Type extensions

Type extensionDescription
ofArray2D(array)
Signature: (array:'T [,]) -> Frame<int,int>
Type parameters: 'T

Create data frame from a 2D array of values. The first dimension of the array is used as rows and the second dimension is treated as columns. Rows and columns of the returned frame are indexed with the element's offset in the array.

Parameters

  • array - A two-dimensional array to be converted into a data frame
ofColumns(cols)
Signature: cols:Series<'?468927,'?468928> -> Frame<'?468929,'?468927>
Type parameters: '?468927, '?468928, '?468929
ofColumns(cols)
Signature: (cols:seq<'?468931 * '?468932>) -> Frame<'K,'?468931>
Type parameters: '?468931, '?468932, 'K
ofRecords(series)
Signature: series:Series<'K,'R> -> Frame<'K,string>
Type parameters: 'K, 'R

Creates a data frame from a series containing any .NET objects. The method uses reflection over the specified type parameter 'T and turns its properties to columns.
ofRecords(values)
Signature: values:seq<'T> -> Frame<int,string>
Type parameters: 'T

Creates a data frame from a sequence of any .NET objects. The method uses reflection over the specified type parameter 'T and turns its properties to columns.
ofRecords(values, indexCol)
Signature: (values:IEnumerable * indexCol:string) -> Frame<'R,string>
Type parameters: 'R

Creates a data frame from a sequence of any .NET objects. The method uses reflection over the specified type parameter 'T and turns its properties to columns.
ofRowKeys(keys)
Signature: keys:seq<'?468925> -> Frame<'?468925,string>
Type parameters: '?468925
ofRows(rows)
Signature: (rows:seq<'?468917 * '?468918>) -> Frame<'?468917,'?468919>
Type parameters: '?468917, '?468918, '?468919
ofRows(rows)
Signature: rows:Series<'?468921,'?468922> -> Frame<'?468921,'?468923>
Type parameters: '?468921, '?468922, '?468923
ofRowsOrdinal(rows)
Signature: rows:seq<'?468913> -> Frame<int,'?468914>
Type parameters: '?468913, '?468914, '?468915

Creates a data frame with ordinal Integer index from a sequence of rows. The column indices of individual rows are unioned, so if a row has fewer columns, it will be successfully added, but there will be missing values.
ofValues(values)
Signature: (values:seq<'?468935 * '?468936 * '?468937>) -> Frame<'?468935,'?468936>
Type parameters: '?468935, '?468936, '?468937

Create a data frame from a sequence of tuples containing row key, column key and a value
ReadCsv(...)
Signature: (path:string * indexCol:string * hasHeaders:bool option * inferTypes:bool option * inferRows:int option * schema:string option * separators:string option * culture:string option * maxRows:int option) -> Frame<'R,string>
Type parameters: 'R

Load data frame from a CSV file. The operation automatically reads column names from the CSV file (if they are present) and infers the type of values for each column. Columns of primitive types (int, float, etc.) are converted to the right type. Columns of other types (such as dates) are not converted automatically.

Parameters

  • path - Specifies a file name or an web location of the resource.
  • indexCol - Specifies the column that should be used as an index in the resulting frame. The type is specified via a type parameter, e.g. use Frame.ReadCsv<int>("file.csv", indexCol="Day").
  • hasHeaders - Specifies whether the input CSV file has header row
  • inferTypes - Specifies whether the method should attempt to infer types of columns automatically (set this to false if you want to specify schema)
  • inferRows - If inferTypes=true, this parameter specifies the number of rows to use for type inference. The default value is 0, meaninig all rows.
  • schema - A string that specifies CSV schema. See the documentation for information about the schema format.
  • separators - A string that specifies one or more (single character) separators that are used to separate columns in the CSV file. Use for example ";" to parse semicolon separated files.
  • culture - Specifies the name of the culture that is used when parsing values in the CSV file (such as "en-US"). The default is invariant culture.
ReadCsv(...)
Signature: (path:string * hasHeaders:bool option * inferTypes:bool option * inferRows:int option * schema:string option * separators:string option * culture:string option * maxRows:int option) -> Frame<int,string>

Load data frame from a CSV file. The operation automatically reads column names from the CSV file (if they are present) and infers the type of values for each column. Columns of primitive types (int, float, etc.) are converted to the right type. Columns of other types (such as dates) are not converted automatically.

Parameters

  • path - Specifies a file name or an web location of the resource.
  • hasHeaders - Specifies whether the input CSV file has header row
  • inferTypes - Specifies whether the method should attempt to infer types of columns automatically (set this to false if you want to specify schema)
  • inferRows - If inferTypes=true, this parameter specifies the number of rows to use for type inference. The default value is 0, meaninig all rows.
  • schema - A string that specifies CSV schema. See the documentation for information about the schema format.
  • separators - A string that specifies one or more (single character) separators that are used to separate columns in the CSV file. Use for example ";" to parse semicolon separated files.
  • culture - Specifies the name of the culture that is used when parsing values in the CSV file (such as "en-US"). The default is invariant culture.
ReadCsv(...)
Signature: (stream:Stream * hasHeaders:bool option * inferTypes:bool option * inferRows:int option * schema:string option * separators:string option * culture:string option * maxRows:int option) -> Frame<int,string>

Load data frame from a CSV file. The operation automatically reads column names from the CSV file (if they are present) and infers the type of values for each column. Columns of primitive types (int, float, etc.) are converted to the right type. Columns of other types (such as dates) are not converted automatically.

Parameters

  • stream - Specifies the input stream, opened at the beginning of CSV data
  • hasHeaders - Specifies whether the input CSV file has header row
  • inferTypes - Specifies whether the method should attempt to infer types of columns automatically (set this to false if you want to specify schema)
  • inferRows - If inferTypes=true, this parameter specifies the number of rows to use for type inference. The default value is 0, meaninig all rows.
  • schema - A string that specifies CSV schema. See the documentation for information about the schema format.
  • separators - A string that specifies one or more (single character) separators that are used to separate columns in the CSV file. Use for example ";" to parse semicolon separated files.
  • culture - Specifies the name of the culture that is used when parsing values in the CSV file (such as "en-US"). The default is invariant culture.
ReadCsv(...)
Signature: (reader:TextReader * hasHeaders:bool option * inferTypes:bool option * inferRows:int option * schema:string option * separators:string option * culture:string option * maxRows:int option) -> Frame<int,string>

Load data frame from a CSV file. The operation automatically reads column names from the CSV file (if they are present) and infers the type of values for each column. Columns of primitive types (int, float, etc.) are converted to the right type. Columns of other types (such as dates) are not converted automatically.

Parameters

  • reader - Specifies the TextReader, positioned at the beginning of CSV data
  • hasHeaders - Specifies whether the input CSV file has header row
  • inferTypes - Specifies whether the method should attempt to infer types of columns automatically (set this to false if you want to specify schema)
  • inferRows - If inferTypes=true, this parameter specifies the number of rows to use for type inference. The default value is 0, meaninig all rows.
  • schema - A string that specifies CSV schema. See the documentation for information about the schema format.
  • separators - A string that specifies one or more (single character) separators that are used to separate columns in the CSV file. Use for example ";" to parse semicolon separated files.
  • culture - Specifies the name of the culture that is used when parsing values in the CSV file (such as "en-US"). The default is invariant culture.
ToDataTable(rowKeyNames)
Signature: rowKeyNames:seq<string> -> DataTable
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