# Dot (inner product)

**URL:** <https://discourse.julialang.org/t/dot-inner-product/17170>\
**Category:** General Usage\
**Tags:** linearalgebra\
**Created:** [November 5, 2018, 2:16pm UTC](https://discourse.julialang.org/t/dot-inner-product/17170 "2018-11-05T14:16:19Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![davidzentlermunro](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/davidzentlermunro/32/5967_2.png) [@davidzentlermunro](https://discourse.julialang.org/u/davidzentlermunro)\
**Post date:** [November 5, 2018, 2:16pm UTC](https://discourse.julialang.org/t/dot-inner-product/17170/1 "2018-11-05T14:16:19Z")

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I’ve just upgraded to v1.0.1 and I’m getting a undefined variable error when I try and use dot(a,b) - error says that dot is not defined. Documentation implies that dot function should still work: [Linear Algebra · The Julia Language](https://docs.julialang.org/en/v1.0/stdlib/LinearAlgebra/#LinearAlgebra.dot) so not sure what’s going on here.

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**Author:** ![raminammour](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/raminammour/32/13572_2.png) [@raminammour](https://discourse.julialang.org/u/raminammour)\
**Post date:** [November 5, 2018, 2:21pm UTC](https://discourse.julialang.org/t/dot-inner-product/17170/2 "2018-11-05T14:21:51Z")

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```julia
using LinearAlgebra

dot(rand(10),rand(10))

```

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**Author:** ![crbinz](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/crbinz/32/1919_2.png) [@crbinz](https://discourse.julialang.org/u/crbinz)\
**Post date:** [November 5, 2018, 2:22pm UTC](https://discourse.julialang.org/t/dot-inner-product/17170/3 "2018-11-05T14:22:32Z")

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> [@PSA: use Julia 0.7 if you are upgrading](https://discourse.julialang.org/t/psa-use-julia-0-7-if-you-are-upgrading/13321):
>
> A lot of people are posting issues where their old code doesn’t work anymore on 1.0 because some function has been renamed or removed. The 0.7 release exists exactly for this reason: your old code will work on 0.7 and give you a specific warning about how to fix your code. If you have any old code, you should use 0.7 to get these warnings before switching to 1.0; even if you just have work habits that may need changing, you should probably use 0.7 for a while. If someone posts an issue like thi…