1 Linear Algebra

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1.1 Matrix Multiplication

Multiply Together a 3 by 2 matrix and a 2 by 1 vector

ar_row_one <- c(-1,+1)
ar_row_two <- c(-3,-2)
ar_row_three <- c(0.35,0.75)
mt_n_by_2 <- rbind(ar_row_one, ar_row_two, ar_row_three)

ar_row_four <- c(3,4)

# Matrix Multiplication
mt_out <- mt_n_by_2 %*% ar_row_four
print(mt_n_by_2)
##               [,1]  [,2]
## ar_row_one   -1.00  1.00
## ar_row_two   -3.00 -2.00
## ar_row_three  0.35  0.75
print(ar_row_four)
## [1] 3 4
print(mt_out)
##                [,1]
## ar_row_one     1.00
## ar_row_two   -17.00
## ar_row_three   4.05