DataFrame Class¶

A DataFrame object, used to communicate data to and from the AMPL entities.

An object of this class can be used to do the following tasks:

Assign values to AMPL entities (once the DataFrame is populated, use ampl.AMPL.SetData to assign its values to the modelling entities in its columns)

Get values from AMPL, decoupling the values from the AMPL entities they originate via ampl.Entities.Entity.GetValues.

A DataFrame object can be created in various ways via the various constructors: create a skeleton manually specifiying the number of indexing columns and the column headers; get column names (and number of indexing columns) from entities of the API passing them directly to the appropriate constructor, get values from AMPL, decoupling the values from the AMPL entities they originate from (via ampl.Entities.Entity.GetValues()).

Populating a DataFrame object can be done adding row by row to a pre-existing skeleton via ampl.DataFrame.AddRow, setting whole columns of a pre-existing skeleton via ampl.DataFrame.SetColumn or adding columns (including indexing columns) via ampl.DataFrame.AddColumn. Modifying a DataFrame object can be done via ampl.DataFrame.SetColumn or via ampl.DataFrame.SetArray or ampl.DataFrame.SetMatrix Accessing data in a DataFrame can be done row by row using ampl.DataFrame.GetRow or by column via ampl.DataFrame.GetColumn.

Namespace

ampl

Assemblies

AMPL

Inheritance Hierarchy
Syntax
Constructors
Methods
Properties

Inheritance Hierarchy ¶

System.Object
ampl.DataFrame

Syntax ¶

public class DataFrame : IEnumerable<DataFrame.Row>, IEnumerable

class ampl.DataFrame

Constructors ¶

DataFrame(System.Int32)¶

Create a new DataFrame with the specified number of indices

public DataFrame(int numberOfIndexColumns)

DataFrame(System.Int32, System.String[])

Create a new DataFrame with the specified number of indices and the specified headers

Arguments

numberOfIndexColumns (System.Int32) – Number of columns to be considered as index for this table (>=0)
headers (System.String<System.String>[]) – Headers (column names)

public DataFrame(int numberOfIndexColumns, params string[] headers)

DataFrame(ampl.Entities.Entity[])

Create a new DataFrame with the specified entities as column headers.

Arguments: headers (ampl.Entities.Entity<ampl.Entities.Entity>[]) – The columns headers to be used; since they are AMPL entities, sets are automatically considered indices and have to be placed first in the constructor.

public DataFrame(params Entity[] headers)

Methods ¶

AddColumn(System.String)¶

Add a new empty column with the corresponding header

Arguments: header (System.String) – The header

public void AddColumn(string header)

AddColumn(System.String, System.Double[])

Add a new column with the corresponding header and values to the dataframe

Arguments

header (System.String) – The name of the new column
values (System.Double<System.Double>[]) – An array of size NumRows with all the values of the new column

public void AddColumn(string header, double[] values)

AddColumn(System.String, System.String[])

Add a new column with the corresponding header and values to the dataframe

Arguments

header (System.String) – The name of the new column
values (System.String<System.String>[]) – An array of size NumRows with all the values of the new column

public void AddColumn(string header, string[] values)

AddRow(System.Object[])¶

Add a row to the DataFrame. The size of the tuple must be equal to the total number of columns in the dataframe.

Arguments: values (System.Object<System.Object>[]) – A collectiong containing all the values for the row to be added

public void AddRow(params object[] values)

AddRow(ampl.Tuple)

Add a row to the DataFrame. The size of the tuple must be equal to the total number of columns in the dataframe.

Arguments: value (ampl.Tuple) – A tuple containing all the values for the row to be added

public void AddRow(Tuple value)

AddRow(ampl.VariantRef)

Add a value to a DataFrame composed of only one column

Arguments: a1 (ampl.VariantRef) – The value to add

public void AddRow(VariantRef a1)

AddRow(ampl.VariantRef, ampl.VariantRef)

Add a value to a DataFrame composed of two columns.

Arguments

a1 (ampl.VariantRef) – Value for the first column
a2 (ampl.VariantRef) – Value for the second column

public void AddRow(VariantRef a1, VariantRef a2)

AddRow(ampl.VariantRef, ampl.VariantRef, ampl.VariantRef)

Add a value to a DataFrame composed of two columns.

Arguments

a1 (ampl.VariantRef) – Value for the first column
a2 (ampl.VariantRef) – Value for the second column
a3 (ampl.VariantRef) – Value for the third column

public void AddRow(VariantRef a1, VariantRef a2, VariantRef a3)

AddRow(ampl.VariantRef, ampl.VariantRef, ampl.VariantRef, ampl.VariantRef)

Add a value to a DataFrame composed of two columns.

Arguments

a1 (ampl.VariantRef) – Value for the first column
a2 (ampl.VariantRef) – Value for the second column
a3 (ampl.VariantRef) – Value for the third column
a4 (ampl.VariantRef) – Value for the fourth column

public void AddRow(VariantRef a1, VariantRef a2, VariantRef a3, VariantRef a4)

Equals(System.Object)¶

Return type: System.Boolean

public override bool Equals(object obj)

GetColumn(System.String)¶

Get the specified column as a view object

Arguments: header (System.String) – The column name
Return type: ampl.DataFrame.Column

public DataFrame.Column GetColumn(string header)

GetEnumerator()¶

Return type: System.Collections.Generic.IEnumerator<ampl.DataFrame.Row>

public IEnumerator<DataFrame.Row> GetEnumerator()

GetHashCode()¶

Return type: System.Int32

public override int GetHashCode()

GetHeaders()¶

Get headers of all columns

Return type: System.String<System.String>[]

public string[] GetHeaders()

GetRow(System.Object[])¶

Get a row by value of the indexing columns. If the index is not specified, gets the only row of a dataframe with no indexing columns.

Arguments: index (System.Object<System.Object>[]) – Collection of objects representing the index of the desired row
Return type: ampl.DataFrame.Row

public DataFrame.Row GetRow(params object[] index)

GetRow(ampl.Tuple)

Get a row by value of the indexing columns. If the index is not specified, gets the only row of a dataframe with no indexing columns.

Arguments: index (ampl.Tuple) – Tuple representing the index of the desired row
Return type: ampl.DataFrame.Row

public DataFrame.Row GetRow(Tuple index)

GetRowByIndex(System.Int32)¶

Get row by numeric index

Arguments: index (System.Int32) – Zero-based index of the row to get
Return type: ampl.DataFrame.Row
Returns: Corresponding row

public DataFrame.Row GetRowByIndex(int index)

Reserve(System.Int32)¶

Reserve space for the given number of rows. NOTE that the rows cannot be accessed, they still have to be added via DataFrame.AddRow.

Arguments: numRows (System.Int32) – Number of rows to be resetved

public void Reserve(int numRows)

SetArray(System.Double[], System.Double[])¶

Set the values of a DataFrame from an array of doubles. The DataFrame must have one index and one data column.

Arguments

indices (System.Double<System.Double>[]) – The indices of the values to set
values (System.Double<System.Double>[]) – An array containing the values to be set

public void SetArray(double[] indices, double[] values)

SetArray(System.Double[], System.String[])

Set the values of a DataFrame from an array of strings. The DataFrame must have one index and one data column.

Arguments

indices (System.Double<System.Double>[]) – The indices of the values to set
values (System.String<System.String>[]) – An array containing the values to be set

public void SetArray(double[] indices, string[] values)

SetArray(System.String[], System.Double[])

Set the values of a DataFrame from an array of doubles. The DataFrame must have one index and one data column.

Arguments

indices (System.String<System.String>[]) – The indices of the values to set
values (System.Double<System.Double>[]) – An array containing the values to be set

public void SetArray(string[] indices, double[] values)

SetArray(System.String[], System.String[])

Set the values of a DataFrame from an array of strings. The DataFrame must have one index and one data column.

Arguments

indices (System.String<System.String>[]) – The indices of the values to set
values (System.String<System.String>[]) – An array containing the values to be set

public void SetArray(string[] indices, string[] values)

SetColumn(System.String, System.Double[])¶

Set the values of a column

Arguments

header (System.String) – The header of the column to be set
values (System.Double<System.Double>[]) – The values to be set

public void SetColumn(string header, params double[] values)

SetColumn(System.String, System.String[])

Set the values of a column

Arguments

header (System.String) – The header of the column to be set
values (System.String<System.String>[]) – The values to be set

public void SetColumn(string header, params string[] values)

SetMatrix(System.Double[], System.Double[], System.Double[])¶

Set a matrix of doubles to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.Double<System.Double>[]) – The values of the first indexing column
indices1 (System.Double<System.Double>[]) – The values of the second indexing column
values (System.Double<System.Double>[,]) – A 2d-array of doubles

public void SetMatrix(double[] indices0, double[] indices1, double[, ] values)

SetMatrix(System.Double[], System.Double[], System.String[])

Set a matrix of strings to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.Double<System.Double>[]) – The values of the first indexing column
indices1 (System.Double<System.Double>[]) – The values of the second indexing column
values (System.String<System.String>[,]) – A 2d-array of strings

public void SetMatrix(double[] indices0, double[] indices1, string[, ] values)

SetMatrix(System.Double[], System.String[], System.Double[])

Set a matrix of doubles to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.Double<System.Double>[]) – The values of the first indexing column
indices1 (System.String<System.String>[]) – The values of the second indexing column
values (System.Double<System.Double>[,]) – A 2d-array of doubles

public void SetMatrix(double[] indices0, string[] indices1, double[, ] values)

SetMatrix(System.Double[], System.String[], System.String[])

Set a matrix of strings to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.Double<System.Double>[]) – The values of the first indexing column
indices1 (System.String<System.String>[]) – The values of the second indexing column
values (System.String<System.String>[,]) – A 2d-array of strings

public void SetMatrix(double[] indices0, string[] indices1, string[, ] values)

SetMatrix(System.String[], System.Double[], System.Double[])

Set a matrix of doubles to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.String<System.String>[]) – The values of the first indexing column
indices1 (System.Double<System.Double>[]) – The values of the second indexing column
values (System.Double<System.Double>[,]) – A 2d-array of doubles

public void SetMatrix(string[] indices0, double[] indices1, double[, ] values)

SetMatrix(System.String[], System.Double[], System.String[])

Set a matrix of strings to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.String<System.String>[]) – The values of the first indexing column
indices1 (System.Double<System.Double>[]) – The values of the second indexing column
values (System.String<System.String>[,]) – A 2d-array of strings

public void SetMatrix(string[] indices0, double[] indices1, string[, ] values)

SetMatrix(System.String[], System.String[], System.Double[])

Set a matrix of doubles to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.String<System.String>[]) – The values of the first indexing column
indices1 (System.String<System.String>[]) – The values of the second indexing column
values (System.Double<System.Double>[,]) – A 2d-array of doubles

public void SetMatrix(string[] indices0, string[] indices1, double[, ] values)

SetMatrix(System.String[], System.String[], System.String[])

Set a matrix of strings to an empty DataFrame. The DataFrame must have two indices and one data column.

Arguments

indices0 (System.String<System.String>[]) – The values of the first indexing column
indices1 (System.String<System.String>[]) – The values of the second indexing column
values (System.String<System.String>[,]) – A 2d-array of strings

public void SetMatrix(string[] indices0, string[] indices1, string[, ] values)

GetEnumerator()

Return type: System.Collections.IEnumerator

IEnumerator IEnumerable.GetEnumerator()

ToString()¶

Return a tabular string representation of the dataframe object.

Return type: System.String

public override string ToString()

Properties ¶

ampl.DataFrame.Item¶

Get the row corresponding to the specified index

Return type: ampl.DataFrame.Row

public DataFrame.Row this[params object[] index] { get; }

ampl.DataFrame.NumCols¶

Get the total number of columns in this dataframe (indexarity + number of values)

Return type: System.Int32

public int NumCols { get; }

ampl.DataFrame.NumIndices¶

Get the number of indices (indexarity) of this dataframe

Return type: System.Int32

public int NumIndices { get; }

ampl.DataFrame.NumRows¶

Get the number of data rows in this dataframe

Return type: System.Int32

public int NumRows { get; }

DataFrame Class¶

Inheritance Hierarchy¶

Syntax¶

Constructors¶

Methods¶

Properties¶

Inheritance Hierarchy ¶

Syntax ¶

Constructors ¶

Methods ¶

Properties ¶