Dataframes

The following scripts assume that you have imported the ColumnType, SeriesI32, SeriesF64, SeriesSTR, Dataframe object from the package as explained in getting started.

Constructors Methods

These methods are used to create new Dataframe.

// Create a Dataframe from Series    let s1 = new SeriesI32("Apple", [1, 2, 3, 4]);    let s2 = new SeriesF64("Orange", [1.1, 2.1, 3.1, 4.1]);    let s3 = new SeriesSTR("Banana", ["ba", "na", "na", "na"]);
    let df = new DataFrame([s1.toJson(), s2.toJson(), s3.toJson()]);    console.table(df.displayTable);
// Create a Dataframe from csv    let file = await fetch("../data/fruits.csv");    let df = await readcsv(file);

Interop Methods

Some handy methods to work with the Dataframes.

// Display Dataframe    console.table(df.displayTable);
// Display Dataframe as String    console.log(df.display);

Utility Methods

Dataframe getters and setters.

// Construct Dataframe    let file = await fetch("../data/fruits.csv");    let df = await readcsv(file);
// Get Dataframe column types    console.log(df.columns());        // {"Orange" => "FLOAT", "Banana" => "STR", "Apple" => "INTEGER"}
// Get number of rows    console.log(df.rowsCount());    // 4
// Get number of columns    console.log(df.columnsCount());    // 3
// Get Dataframe column names    console.log(df.columns());      // ["Apple", "Orange", "Banana"]

Additional Methods for Dataframe

// Create a Dataframe from Series    let s1 = new SeriesI32("Apple", [1, 2, 3, 4]);    let s2 = new SeriesF64("Orange", [1.1, 2.1, 3.1, 4.1]);    let s3 = new SeriesSTR("Banana", ["ba", "na", "na", "na"]);
    let df = new DataFrame([s1.toJson(), s2.toJson(), s3.toJson()]);
// Append new Series    let s4 = new SeriesI32("Fruits", [9, 8, 9, 8]);    df.append(ColumnType.INTEGER, sertest.toJson());    console.log(df.display); // String output

note

While appending new Series to Dataframe, you have to specify the type via ColumnType.Integer, ColumnType.Float or ColumnType.String.

// Get Series with column name    console.log(df.loc("Banana"));     // String output
// Get Dataframe row    console.log(df.ilocr(2));     // [3, 3.1, "na"]
// Get Dataframe column    console.log(df.ilocc(1));    // [1.1, 2.1, 3.1, 4.1]

Math Methods

Methods to perform simple mathematical operations on the Dataframe.

// Get minimun of all columns    console.log(df.minColumns());    // {"Fruits" => 8, "Apple" => 1, "Orange" => 1.1}
// Get maximum of all columns    console.log(df.maxColumns());    // {"Fruits" => 9, "Apple" => 4, "Orange" => 4.1}// Get mean of all columns    console.log(df.meanColumns());    // {"Apple" => 2.5, "Fruits" => 8.5, "Orange" => 2.6}
// Get median of all columns    console.log(df.medianColumns());    // {"Apple" => 2.5, "Orange" => 2.6, "Fruits" => 8.5}
// Get varience of all columns params (degree_of_freedom)    console.log(df.varianceColumns(1));    // {"Apple" => 2, "Orange" => 1.666666666666666, "Fruits" => 0.6666666666666666}
// Get variance of Dataframe column params (column_name, degree_of_freedom)    console.log(df.variance("Apple", 1));    // 2
// Get standard deviation of Dataframe params (degree_of_freedom)    console.log(df.standardDeviationColumns(1));    // {"Orange" => 1.2909944487358054, "Fruits" => 0.816496580927726, "Apple" => 1.4142135623730951}
// Get standard deviation of Dataframe column params (column_name, degree_of_freedom)    console.log(df.standardDeviation("Orange", 1));    // 1.2909944487358054

note

SeriesSTR columns are not taken into account while performing math methods