rm(list=ls())
library(LalRUtils)
load_or_install(c('tidyverse','data.table','magrittr','lfe','devtools'))
(X = rbind(c(1,4,5),c(10,2,3)))
(Y = rbind(c(2,3),c(1,5), c(3,5)))
X %*% Y
1 | 4 | 5 |
10 | 2 | 3 |
2 | 3 |
1 | 5 |
3 | 5 |
21 | 48 |
31 | 55 |
(X = rbind(c(2,3,4), c(3,1,3), c(2,4,2)))
(X_inv = solve(X))
X %*% X_inv
2 | 3 | 4 |
3 | 1 | 3 |
2 | 4 | 2 |
-0.5 | 0.5 | 0.25 |
0.0 | -0.2 | 0.30 |
0.5 | -0.1 | -0.35 |
1 | 0 | -2.22e-16 |
0 | 1 | 0.00e+00 |
0 | 0 | 1.00e+00 |