# Can not access geqrf!() function in LinearAlgebra Standard Library Package Julia 1.3.0

**URL:** <https://discourse.julialang.org/t/can-not-access-geqrf-function-in-linearalgebra-standard-library-package-julia-1-3-0/32796>\
**Category:** General Usage\
**Created:** [December 30, 2019, 1:39pm UTC](https://discourse.julialang.org/t/can-not-access-geqrf-function-in-linearalgebra-standard-library-package-julia-1-3-0/32796 "2019-12-30T13:39:43Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![dataDiver](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/datadiver/32/8174_2.png) [@dataDiver](https://discourse.julialang.org/u/dataDiver)\
**Post date:** [December 30, 2019, 1:39pm UTC](https://discourse.julialang.org/t/can-not-access-geqrf-function-in-linearalgebra-standard-library-package-julia-1-3-0/32796/1 "2019-12-30T13:39:44Z")

</div>

Trying to run `geqrf!()` function from the [manual](https://docs.julialang.org/en/v1/stdlib/LinearAlgebra/#LinearAlgebra.LAPACK.geqrf!)

```julia
using LinearAlgebra
Q = rand(10, 5); tau = zeros(5)
geqrf!(Q, tau)
# ERROR: UndefVarError: geqrf! not defined

```

---

<div class="post-metadata">

**Author:** ![dataDiver](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/datadiver/32/8174_2.png) [@dataDiver](https://discourse.julialang.org/u/dataDiver)\
**Post date:** [December 30, 2019, 2:22pm UTC](https://discourse.julialang.org/t/can-not-access-geqrf-function-in-linearalgebra-standard-library-package-julia-1-3-0/32796/2 "2019-12-30T14:22:02Z")

</div>

Never mind

```julia
LAPACK.gerf!(x, tau) # works

```

---

<div class="post-metadata">

**Author:** ![dataDiver](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/datadiver/32/8174_2.png) [@dataDiver](https://discourse.julialang.org/u/dataDiver)\
**Post date:** [December 30, 2019, 2:32pm UTC](https://discourse.julialang.org/t/can-not-access-geqrf-function-in-linearalgebra-standard-library-package-julia-1-3-0/32796/3 "2019-12-30T14:32:08Z")

</div>

Hmm … but do I import `gerf!` function without having to always use `LAPACK` prefix?

---

<div class="post-metadata">

**Author:** ![jonasaugust](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jonasaugust/32/11942_2.png) [@jonasaugust](https://discourse.julialang.org/u/jonasaugust)\
**Post date:** [December 30, 2019, 3:03pm UTC](https://discourse.julialang.org/t/can-not-access-geqrf-function-in-linearalgebra-standard-library-package-julia-1-3-0/32796/4 "2019-12-30T15:03:24Z")

</div>

`geqrf!` doesn’t appear to be exported (see [https://github.com/JuliaLang/julia/blob/master/stdlib/LinearAlgebra/src/lapack.jl](https://github.com/JuliaLang/julia/blob/master/stdlib/LinearAlgebra/src/lapack.jl)), and if you look at how functions in LAPACK are tested, the LAPACK prefix is used by the developers: [https://github.com/JuliaLang/julia/blob/master/stdlib/LinearAlgebra/test/lapack.jl](https://github.com/JuliaLang/julia/blob/master/stdlib/LinearAlgebra/test/lapack.jl)

Alternatively, you can just `import LinearAlgebra.LAPACK.geqrf!` and then `geqrf!` is available, without prefix.