# Pkg.add("SweepOperator")
using SweepOperator

srand(280)

X = randn(5, 3) # predictor matrix
y = randn(5)    # response vector

# form the augmented Gram matrix
G = [X y]' * [X y]

sweep!(G, 1:3)

# least squares solution by QR
X \ y

# inverse sweep to restore original matrix
sweep!(G, 1:3, true)

versioninfo()