# false\*NaN = 0.0

**URL:** <https://discourse.julialang.org/t/false-nan-0-0/8477>\
**Category:** New to Julia\
**Created:** [January 19, 2018, 2:57pm UTC](https://discourse.julialang.org/t/false-nan-0-0/8477 "2018-01-19T14:57:29Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Paul\_Soderlind](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/paul_soderlind/32/1753_2.png) [@Paul\_Soderlind](https://discourse.julialang.org/u/Paul_Soderlind)\
**Post date:** [January 19, 2018, 2:57pm UTC](https://discourse.julialang.org/t/false-nan-0-0/8477/1 "2018-01-19T14:57:29Z")

</div>

while `convert(Int,false)*NaN = NaN`

Where can I read up on this?

---

<div class="post-metadata">

**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [January 19, 2018, 3:04pm UTC](https://discourse.julialang.org/t/false-nan-0-0/8477/2 "2018-01-19T15:04:21Z")

</div>

Some breadcrumbs:

The executed function has the explicit comment:

```julia
# make `false` a "strong zero": false*NaN == 0.0

```

Comment added in PR: [https://github.com/JuliaLang/julia/pull/23433/](https://github.com/JuliaLang/julia/pull/23433/)  
references [https://github.com/JuliaLang/julia/issues/19168#issuecomment-324734034](https://github.com/JuliaLang/julia/issues/19168#issuecomment-324734034)