Javascript Algorithm:Matrix Addition

A matrix in arrangement of numbers into rows and columns.In JS a matrix can be

represented with arrays and multi dimensional arrays can be created by nesting

arrays. So in this problem we can use the terms matrices and arrays

interchangeably.

e.g. suppose we want to represent a 2 row 2 column matrix in javascript then

it will look like

let twoDimArr = [

[1,2],

[3, 4]

];

Sum of two matrices:

Fo given two N x M matrices,their sum is again a N x M matrix where each value

in that matrix the sum of values of corresponding elements of the given two

matrices

Sum of Two matrices using by falttening them to one dimesional matrices:

Solution:

let matrixA = [

[1, 1, 1, 1],

[2, 2, 2, 2],

[3, 3, 3, 3],

[4, 4, 4, 4],

];

let matrixB = [

[1, 1, 1, 1],

[2, 2, 2, 2],

[3, 3, 3, 3],

[4, 4, 4, 4],

];

let flattenMatrixA = Array.from(matrixA.flat());

let flattenMatrixB = Array.from(matrixB.flat());

let sumOfFlattenMatrices = flattenMatrixA.map((elem, i) =>

                elem + flattenMatrixB[i]);

let resultMatrix = [];

while (sumOfFlattenMatrices.length) {

resultMatrix.push(sumOfFlattenMatrices.splice(0, matrixA[0].length));

}

console.log(resultMatrix)

Output:

[ [ 2, 2, 2, 2 ], [ 4, 4, 4, 4 ], [ 6, 6, 6, 6 ], [ 8, 8, 8, 8 ] ]

Using Array.map:

Solution:

let matrixA = [

[1, 1, 1, 1],

[2, 2, 2, 2],

[3, 3, 3, 3],

[4, 4, 4, 4],

];

let matrixB = [

[1, 1, 1, 1],

[2, 2, 2, 2],

[3, 3, 3, 3],

[4, 4, 4, 4],

];

let resultMatrix = matrixA.map((matrioxARowElement,rowIndex)=>{

return matrioxARowElement.map((element,colIndex)=>{

return element + matrixB[rowIndex][colIndex]

})

})

console.log(resultMatrix)

Output:

[ [ 2, 2, 2, 2 ], [ 4, 4, 4, 4 ], [ 6, 6, 6, 6 ], [ 8, 8, 8, 8 ] ]

Using Loop:

Solution:

let matrixA = [

[1, 1, 1, 1],

[2, 2, 2, 2],

[3, 3, 3, 3],

[4, 4, 4, 4],

];

let matrixB = [

[1, 1, 1, 1],

[2, 2, 2, 2],

[3, 3, 3, 3],

[4, 4, 4, 4],

];

let result = [];

for (let i = 0; i < matrixA.length; i++) {

let row = [];

for (let j = 0; j < matrixA[0].length; j++) {

row.push(matrixA[i][j] + matrixB[i][j]);

}

result.push(row)

}

console.log(result)

Output:

[ [ 2, 2, 2, 2 ], [ 4, 4, 4, 4 ], [ 6, 6, 6, 6 ], [ 8, 8, 8, 8 ] ]