Class DataFrame

The columns in the data frame.

Example

//Gives an array of column names.
const columns = df.columns; //['name', 'age', 'gender']
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The columns in the data frame.

Example

//Gives a 2D array .
const data = df.data; //[['Alice', 30, 'Female'], ['Bob', 25, 'Male'], ['Charlie', 40, 'Male']];
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The number of rows in the data frame.

Example

//Gives the number of rows in the data frame.
const rows = df.rows; //3
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The shape of the data frame as a tuple of [number of rows, number of columns].

Example

const shape = df.shape; // [3, 2]
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Adds two columns together and returns the result as a new DataFrame object.

Example

//Add a new column whose values = sum('col1', 'col2')
const newDf = df.addColumns("col1 + col2", "col1", "col2");

//Output:
   col1  col2  col1 + col2
 1    1    2      3
 2    2    3      5
 3    3    4      7
 4    4    5      9
 5    5    6      11
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Example

const correlation = df.correlation('age', 'height'); //0.5
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Returns a detailed string representation of the data frame. Prints all rows.

Example

//Print complete rows/data of the data frame.
console.log(df.details());
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Drops a column from the data frame.

Example

//Drop age column from the data frame.

const df = new DataFrame({
  columns: ['Name', 'Age', 'Gender'],
  data: [
    ['Alice', 30, 'Female'],
    ['Bob', 25, 'Male'],
    ['Charlie', 40, 'Male'],
  ],
});

const newDf = df.dropColumn('Age');

console.log(newDf.data); //[['Alice', 'Female'], ['Bob', 'Male'], ['Charlie', 'Male']]
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Filters the DataFrame object by a column value and returns the filtered DataFrame object.

Example

//filter data frame based on age = 21
const newDf = df.filter("age", 21);

//Output:
     name     age
 1    Jack     21
 2    Jone     21
 3    Paul     21
 4    Tim      21
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Returns an object containing the data types of each column in the data frame.

Example

//Gives an object containing the data types of each column.
const columnTypes = df.getColumnTypes(); // {Name: 'string', Age: 'number', Gender: 'string'}
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Groups the DataFrame object by one or more columns and returns a GroupBy object.

Example

//group the data frame by gender column

const groupedData = df.groupBy(df, ["gender"]);

//Output:
{
   Female: DataFrame {
       _columns: [ 'Name', 'Age', 'Gender' ],
       _data: [ [Array] ]
   },
   Male: DataFrame {
       _columns: [ 'Name', 'Age', 'Gender' ],
       _data: [ [Array], [Array] ]
   }
}
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Returns the first n rows of the data frame.

Example

//Give a new data frame containing the first 5 rows of the data frame.
const newDf = df.head(); 

or

//Give a new data frame containing the first 3 rows of the data frame.
const newDf = df.head(3);
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Calculates the mean of the given columns.

Example

const mean = df.mean(['age']); // { age: 47.5 }
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Calculates the median of the given columns.

Example

const median = df.median(['age']); // { age: 47 }
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Calculates the mode of the given columns.

Example

const mode = df.mode(['age']); // { age: 47 }
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Renames a column in the data frame.

Example

//Rename age column to newAge.

const newDf = df.renameColumn('Age', 'newAge');
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Returns a new data frame with only the specified columns.

Example

//Gives a new data frame with only the name and age columns.

const newDf = df.select(['name', 'age']);
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Sorts the DataFrame object by one or more columns and returns the sorted DataFrame object.

Example

//Sort data frame by age column in descending order.
const newDf = df.sort(["age"], ["desc"]);

//Output:
     name     age
 1    Jack     26
 2    Jone     25
 3    Paul     22
 4    Tim      21
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Calculates the standard deviation of the given columns.

Example

const standardDeviation = df.standardDeviation(['age']); // { age: 4.5 }
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Returns the last n rows of the data frame.

Example

//Give a new data frame containing the last 5 rows of the data frame.
const newDf = df.tail(); 

or

//Give a new data frame containing the last 3 rows of the data frame.
const newDf = df.tail(3);
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Writes the data frame to a CSV file.

Example

//Write the data frame to a CSV file.
df.toCSV('path/to/file.csv');
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Writes the data frame to a JSON file.

Example

//Write the data frame to a JSON file.
df.toJSON('path/to/file.json');
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Returns a string representation of the data frame. Prints only first 5 rows and last 5 rows

Example

const df = new DataFrame({
  columns: ['Name', 'Age', 'Gender'],
  data: [
    ['Alice', 30, 'Female'],
    ['Bob', 25, 'Male'],
    ['Charlie', 40, 'Male'],
  ],
});

console.log(df.toString());

//Output:

DataFrame
Shape: (3,3)


   Name                    Age                     Gender    

  1       Alice                   30                      Female    
  2       Bob                     25                      Male      
  3       Charlie                 40                      Male
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