D3.js group() Method Last Updated : 23 Sep, 2020 Summarize Comments Improve Suggest changes Share Like Article Like Report With the help of d3.group() method, we can group the iterable data structure into a map where the key is defined as the element from iterable and values as an array. Syntax: d3.group( iterable, ...keys ) Return value: It returns the map having key as element and value as an array. Note: To execute the below examples you have to install the d3 library by using this command prompt we have to execute the following command. npm install d3 Example 1: In this example, we can see that by using the d3.group() method. We are able to get the map from the group iterable where the key is an element and the value as an array. JavaScript // Defining d3 contrib variable var d3 = require('d3'); data = [ {name: "ABC", amount: "34.0", date: "11/12/2015"}, {name: "DEF", amount: "120.11", date: "11/12/2015"}, {name: "MNO", amount: "12.01", date: "01/04/2016"}, {name: "XYZ", amount: "34.05", date: "01/04/2016"} ] var grouped_data = d3.group(data, d => d.name) console.log(grouped_data) Output: Map { 'ABC' => [ { name: 'ABC', amount: '34.0', date: '11/12/2015' } ], 'DEF' => [ { name: 'DEF', amount: '120.11', date: '11/12/2015' } ], 'MNO' => [ { name: 'MNO', amount: '12.01', date: '01/04/2016' } ], 'XYZ' => [ { name: 'XYZ', amount: '34.05', date: '01/04/2016' } ] } Example 2: JavaScript // Defining d3 contrib variable var d3 = require('d3'); data = [ {name: "ABC", amount: "34.0", date: "11/12/2015"}, {name: "DEF", amount: "120.11", date: "11/12/2015"}, {name: "MNO", amount: "12.01", date: "01/04/2016"}, {name: "XYZ", amount: "34.05", date: "01/04/2016"} ] var grouped_data = d3.group(data, d => d.name, d => d.amount) console.log(grouped_data) Output: Map { 'ABC' => Map { '34.0' => [ [Object] ] }, 'DEF' => Map { '120.11' => [ [Object] ] }, 'MNO' => Map { '12.01' => [ [Object] ] }, 'XYZ' => Map { '34.05' => [ [Object] ] } } Comment More infoAdvertise with us Next Article D3.js group.get() Method J jitender_1998 Follow Improve Article Tags : JavaScript Web Technologies D3.js Similar Reads D3.js group.get() Method With the help of d3.group.get() method, we can get the values from the resulting map obtained by grouping an iterable data structure. Syntax: d3.group.get( value ) Return value: It returns the values from the map. Note: To execute the below examples you have to install the d3 library by using this c 2 min read Collect.js groupBy() Method Collect.js is a wrapper library for working with arrays and objects which is dependency-free and easy to use. The groupBy() method is used to group the given collection items into multiple collections by a given key Syntax: collect(array).groupBy(key) Parameters: The collect() method takes one argum 2 min read D3.js Array.from() Method With the help of Array.from() method, we can convert the map into an array by using this method. Syntax : Array.from( map ) Return value: It returns an array of different elements. Note: To execute the below examples you have to install the d3 library by using the command prompt we have to execute t 2 min read Lodash _.groupBy() Method Lodash's _.groupBy() method groups elements of a collection into an object, using the results of an iterated function as keys, with corresponding arrays of elements that generate each key.Syntax:_.groupBy(collection, [iteratee]);Parameters:Collection: It is the collection that the method iterates ov 2 min read D3.js index() method With the help of d3.index() method, we can get the map having key as an element but the change is that we get object as unique values instead of an array. Syntax: d3.index(iterable, ...keys) Return value: It returns the map of objects. Note: To execute the below examples you have to install the d3 l 2 min read Node.js console.group() Method The console. group() method is an inbuilt application programming interface of the console module which is used to print passed content in a grouped style. It indicates the start of a message group. To end this group we can use console. groupEnd() method. Syntax: console.group([label]); Parameters: 3 min read Like