Unable to initialise a matrix

Question

I wanted to create a matrix in R so I typed this:

a<- matrix(c(1:5), nrow = 2, byrow = TRUE)
print(a)

But instead of it executing it gives the error:

Error in matrix(c(1:5), nrow = 2, byrow = TRUE) : unused arguments (c(1:5), nrow = 2, byrow = TRUE)

At first i thought I had gotten the syntax wrong but i pasted many examples from different sites but same issue.

Answer 1

I got the same output as Peace. The main problem is the number of entries in the matrix. There are 5 entries for 2 rows. As mentioned in the warning 5 is not a multiple of 2. So R uses the first entry, which is 1 in our case, again as the second-row third-column entry of the matrix.

a<- matrix(c(1:5), nrow = 2, byrow = TRUE)
#> Warning in matrix(c(1:5), nrow = 2, byrow = TRUE): data length [5] is not a sub-
#> multiple or multiple of the number of rows [2]
print(a)
#>      [,1] [,2] [,3]
#> [1,]    1    2    3
#> [2,]    4    5    1

^{Created on 2022-01-26 by the reprex package (v2.0.1)}

When you change the entries of the matrix as below, there is no problem:

a<- matrix(c(1:6), nrow = 2, byrow = TRUE)
print(a)
#>      [,1] [,2] [,3]
#> [1,]    1    2    3
#> [2,]    4    5    6

^{Created on 2022-01-26 by the reprex package (v2.0.1)}