solve_linear_alg.R

# So R can solve linear algebra too!

lhs <- matrix(c(2, -1, 0, -1, 2, -3, 0, -1, 4), nrow=3)
"
     [,1] [,2] [,3]
[1,]    2   -1    0
[2,]   -1    2   -1
[3,]    0   -3    4
"

rhs <- matrix(c(0, -1, 4))
"
     [,1]
[1,]    0
[2,]   -1
[3,]    4
"

soln <- solve(lhs, rhs)
"
     [,1]
[1,]    0
[2,]    0
[3,]    1
"

# prove it so
lhs %*% soln == rhs
"
     [,1]
[1,] TRUE
[2,] TRUE
[3,] TRUE
"