Matrix

A matrix for Swift. Written to learn some Swift language features.

Disclaimer

• not designed to be performant (though designed to allow for Accelerate usage later)
• not unit tested (so there are probably bugs, proceed with caution)
• not fully fleshed (no determinants or anything fancy)

Future Ideas

• implement Accelerate
• add feature similar to find() in Matlab
• allow indexing by matrices (similar to Matlab)

Example (from main.swift)

//  simple helper functions
print(Matrix.I(3))
print(Matrix.diagonal([1, 2, 3]))

//  transpose a matrix
print(Matrix([[1, 2]]).transpose())

//  add, subtract, multiply and divide by and from scalars
print((Matrix.ones(3, 3) * 10.0) + (Matrix.zeros(3, 3) + 5.0))

//  multiply matrices
print(Matrix([[1, 2], [3, 4]]) * Matrix([[1, 2]]).transpose())

//  map functions ((Double) -> Double) to a matrix
//  string conversion with adjustable output precision
print(Matrix([[0, 30], [60, 90]]).map{sin($0 * 3.14159 / 180)}.toString(10))

//  combine two matrices with a function ((Double, Double) -> Double)
print(Matrix.I(3).combine(Matrix.I(3), operation: { $0 - 5 * $1}))

let z = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
//  set individual rows and columns
z[0, [0, 2]] = Matrix([[-5]])
print(z)

//  index with any combination of int, Array<Int>, Range<Int> and StrideThrough<Int>
z[1, z.allCols] = Matrix([[20, 20, 20]])
print(z)