how to use the groupby function from the lodash library in typescript

To use the groupBy function from the Lodash library in TypeScript, you have to install the Lodash library using npm:

npm install lodash
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Then, you can import the groupBy function in your TypeScript file:

index.ts
import {groupBy} from 'lodash';
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And use the function like this:

index.ts
const numbers = [1.2, 1.3, 2.1, 2.4, 3.5, 3.9];

const grouped = groupBy(numbers, Math.floor);

console.log(grouped);
// Output: { '1': [ 1.2, 1.3 ], '2': [ 2.1, 2.4 ], '3': [ 3.5, 3.9 ] }
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In this example, the groupBy function is used to group an array of numbers by their integer part. The Math.floor function is used as the grouping criterion. The resulting object has each group key as a string, and the corresponding group elements as an array.

Note: To use the Lodash library in TypeScript, you need the @types/lodash package to get type definitions. You can install it like this:

npm install @types/lodash
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