Swift matrix sum

Question

I\'m trying to develop a func which allows to sum two matrix if they are equals to the same dimension, but I get an error \"EXC_BAD_INSTRUCTION\" on the try.

Here is

Answer 1

swift 4 - Addition 0f 3 x 3 Matrices

enum RisedError: Error {
        case DimensionNotEquals
        case Obvious(String)
    }
    func ==(lhs: Matrix, rhs: Matrix) -> Bool {
        return (lhs.rows) == (rhs.rows) && (lhs.columns) == (rhs.columns)
    }
    protocol Operation {
        mutating func sumWith(matrixB: Matrix) throws -> Matrix

    }
    class ViewController: UIViewController {


    //Matrix creation
        func matrixCreation(){
            var matrixA = Matrix(rows: 3, columns: 3)
            var matrixB = Matrix(rows: 3, columns: 3)
            matrixA[0,0] = 1.0
            matrixA[0, 1] = 2.0
            matrixA[0, 2] = 2.0
            matrixA[1, 0] = 3.0
            matrixA[1, 1] = 4.0
            matrixA[1, 2] = 4.0
            matrixA[2, 0] = 1.0
            matrixA[2, 1] = 1.0
            matrixA[2, 2] = 1.0
            matrixB[0,0] = 5.0
            matrixB[0, 1] = 6.0
            matrixB[0, 2] = 6.0
            matrixB[1, 0] = 7.0
            matrixB[1, 1] = 8.0
            matrixB[1, 2] = 8.0
            matrixB[2, 0] = 1.0
            matrixB[2, 1] = 1.0
            matrixB[2, 2] = 1.0

            var outputMartix = Matrix(rows: 3, columns: 3)
            print(matrixB , matrixA)
            do {
                outputMartix = try! matrixA.sumWith(matrixB: matrixB)
                print(outputMartix)
            }catch RisedError.DimensionNotEquals{
                print("Dimensions are not equal")

            }
        }

    }

    //Matrix Configuration

    struct Matrix {
        let rows: Int, columns: Int
        var grid: [Double]
        init(rows: Int, columns: Int) {
            self.rows = rows
            self.columns = columns
            grid = Array(repeating: 0.0, count: rows * columns)
        }
        func indexIsValidForRow(row: Int, column: Int) -> Bool {
            return row >= 0 && row < rows && column >= 0 && column < columns
        }
        subscript(row: Int, column: Int) -> Double {
            get {
                assert(indexIsValidForRow(row: row, column: column), "Index out of range")
                return grid[(row * columns) + column]
            }
            set {
                assert(indexIsValidForRow(row: row, column: column), "Index out of range")
                grid[(row * columns) + column] = newValue
            }
        }
    }
    extension Matrix: Operation {

        mutating func sumWith(matrixB: Matrix) throws -> Matrix {

            guard self == matrixB else { throw RisedError.DimensionNotEquals }

            for row in 0...self.rows - 1 {
                for column in 0...self.columns - 1 {
                    self[row, column] = matrixB[row, column] + self[row, column]
                }
            }
            return self
        }
    }