eryn/three-dee
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

[Math] Move the multiplication to the * operator

Browse source 
*= must be done with a temporary variable first to avoid stepping on the other elements.
This commit is contained in:
Eryn Wells 2015-11-01 20:40:27 -08:00
parent 65823610c1
commit 541e7c38ef
1 changed files with 12 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

21
Math/Math/Matrix.swift
View file

@ -270,19 +270,22 @@ public func -<T: Matrix>(lhs: T, rhs: T) -> T {
// MARK: Matrix-Matrix multiplication
public func *=<T: Matrix>(inout lhs: T, rhs: T) {
for i in 0..<T.dimension {
for j in 0..<T.dimension {
// Each cell is Sigma(k=0, M)(lhs[ik] * rhs[kj]
for k in 0..<T.dimension {
lhs[i,j] += lhs[i,k] * rhs[k,j]
}
}
let result = lhs * rhs
for i in 0..<T.count {
lhs[i] = result[i]
}
}
public func *<T: Matrix>(lhs: T, rhs: T) -> T {
var out = lhs
out *= rhs
var out = T()
for i in 0..<T.dimension {
for j in 0..<T.dimension {
// Each cell is Sigma(k=0, M)(lhs[ik] * rhs[kj]
for k in 0..<T.dimension {
out[i,j] += lhs[i,k] * rhs[k,j]
}
}
}
return out
}