how to use the unzipwith function from lodash in javascript

The unzipWith function from lodash is used to transpose the rows and columns of a matrix and apply a custom function to the values in each row. Here is an example of how to use unzipWith in Javascript:

index.tsx
const _ = require('lodash'); // import lodash library

const matrix = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]; // a matrix of numbers

const result = _.unzipWith(matrix, (row) => {
  return _.sum(row); // returns the sum of values in each row
});

console.log(result); // [12, 15, 18]
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In this example, we import the lodash library, define a matrix with three rows and three columns, and pass it to unzipWith along with a custom function that sums the values in each row. The result variable stores the transposed matrix output and the console.log statement displays the result.

Note that unzipWith must be used in conjunction with zipWith to construct the original matrix. Here is an example:

index.tsx
const matrix = [[1, 10], [2, 20], [3, 30]]; // a matrix of numbers

const zipped = _.zipWith(...matrix, (a,b,c) => [a,b,c]); // zips the matrix together

console.log(zipped); // [[1,2,3], [10,20,30]]

const unzipped = _.unzipWith(zipped, (row) => {
  return _.sum(row); // returns the sum of values in each row
});

console.log(unzipped); // [6, 60]
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In this example, zipWith is used to zip the columns of the original matrix together into an array of rows. The unzipWith function is then called on the transposed matrix to apply a custom function to each row. The console.log statements show the original matrix and the transposed matrix output, respectively.