Linear Algebra in Julia

Question

I'm attempting to use Julia for some Linear Algebra. The documentation lists a number of functions suitable for working with matrices. Some of these work directly on running Julia e.g.

julia> ones(2,2)
2×2 Array{Float64,2}:
 1.0  1.0
 1.0  1.0

while others give an UndefVarError e.g.

julia> eye(2,2)
ERROR: UndefVarError: eye not defined
Stacktrace:
 [1] top-level scope at none:0

Why am I only able to access some of the functions listed on the Linear Algebra section? https://michaelhatherly.github.io/julia-docs/en/latest/stdlib/linalg.html#Base.LinAlg.expm

I have also tried importing the LinearAlgebra package but this doesn't make a difference:

julia> using LinearAlgebra

julia> eye(2,2)
ERROR: UndefVarError: eye not defined
Stacktrace:
 [1] top-level scope at none:0

In fact some functions now become available e.g. dot, whilst others which according to the documentation are also part of the Linear Algebra library continue to give an error:

julia> dot
ERROR: UndefVarError: dot not defined

julia> using LinearAlgebra

julia> dot
dot (generic function with 12 methods)

julia> vecdot
ERROR: UndefVarError: vecdot not defined

Both of the above functions are listed as Base.LinAlg.dot in the documentation.

The packages I currently have installed are:

(v1.0) pkg> status
    Status `~/.julia/environments/v1.0/Project.toml`
  [0c46a032] DifferentialEquations v5.3.1
  [7073ff75] IJulia v1.13.0
  [91a5bcdd] Plots v0.21.0
  [37e2e46d] LinearAlgebra 
  [2f01184e] SparseArrays 

This problem occurs for many other functions discussed on the linear algebra page:

julia> repmat([1, 2, 3], 2)
ERROR: UndefVarError: repmat not defined
Stacktrace:
 [1] top-level scope at none:0

I have Julia vs1.01 installed

Answer 1

The documentation you linked to is not the official documentation, which is found at docs.julialang.org. The docs you linked to are an old version on some developer's website. That is the reason why it doesn't line up with the current Julia.