Task

Build an   identity matrix   of a size known at run-time.



An identity matrix is a square matrix of size n × n,

where the diagonal elements are all 1s (ones),

and all the other elements are all 0s (zeroes).







I

n


=


[



1


0


0


⋯


0




0


1


0


⋯


0




0


0


1


⋯


0




⋮


⋮


⋮


⋱


⋮




0


0


0


⋯


1



]




{\displaystyle I_{n}={\begin{bmatrix}1&0&0&\cdots &0\\0&1&0&\cdots &0\\0&0&1&\cdots &0\\\vdots &\vdots &\vdots &\ddots &\vdots \\0&0&0&\cdots &1\\\end{bmatrix}}}





Related tasks

   Spiral matrix
   Zig-zag matrix 
   Ulam_spiral_(for_primes)


package main
 
import (
    "fmt"
 
    "gonum.org/v1/gonum/mat"
)
 
func eye(n int) *mat.Dense {
    m := mat.NewDense(n, n, nil)
    for i := 0; i < n; i++ {
        m.Set(i, i, 1)
    }
    return m
}
 
func main() {
    fmt.Println(mat.Formatted(eye(3)))
}