groupby.ngroups.md

description
Obtain the number of groups

Groupby.ngroups

danfo.Groupby.ngroups [source]

Parameters: None

Return: Number

Examples

Obtain the number of groups in a dataframe grouped by one column

{% tabs %} {% tab title="Node" %}

const dfd = require("danfojs-node")

let data ={A: ['foo', 'bar', 'foo', 'bar',
                'foo', 'bar', 'foo', 'foo'],
           B: ['one', 'one', 'two', 'three',
                'two', 'two', 'one', 'three'],
           C: [1,3,2,4,5,2,6,7],
           D: [3,2,4,1,5,6,7,8]
        }

let df = new dfd.DataFrame(data)


let grp = df.groupby(["A"])
console.log(grp.ngroups)

{% endtab %} {% endtabs %}

2

Obtain the number of groups in dataframe grouped by two columns

{% tabs %} {% tab title="Node" %}

const dfd = require("danfojs-node")

let data ={A: ['foo', 'bar', 'foo', 'bar',
                'foo', 'bar', 'foo', 'foo'],
           B: ['one', 'one', 'two', 'three',
                'two', 'two', 'one', 'three'],
           C: [1,3,2,4,5,2,6,7],
           D: [3,2,4,1,5,6,7,8]
}

let df = new dfd.DataFrame(data)
let grp = df.groupby(["A","B"])
console.log(grp.ngroups)

{% endtab %} {% endtabs %}

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