# Generate a random number exclusive on both sides: smaller# \< x \< larger#?
**URL:** https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719
**Category:** General Usage
**Tags:** question
**Created:** [March 10, 2022, 9:32pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719 "2022-03-10T21:32:41Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@Bob\_Bass](https://discourse.julialang.org/u/Bob_Bass)
#### Post date: [March 10, 2022, 9:32pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719/1 "2022-03-10T21:32:41Z")
Hi.
How can I generate a random real number between -3 and 3 that is exclusive on both sides?
Thank you.
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### Author:  [@MarcBerliner](https://discourse.julialang.org/u/MarcBerliner)
#### Post date: [March 10, 2022, 9:39pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719/2 "2022-03-10T21:39:31Z")
`rand()*(3.0 - (-3.0)) + (-3.0)`
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### Author:  [@stevengj](https://discourse.julialang.org/u/stevengj)
#### Post date: [March 10, 2022, 9:43pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719/3 "2022-03-10T21:43:00Z")
> [@MarcBerliner](#):
>
> rand()\*(3.0 - (-3.0)) + (-3.0)
That doesn’t exclude `-3.0`, because `rand()` is uniform in `[0,1)`.
See this answer: [How to create a random Uniform Distribution between (but excluding) 0 and 10? - #21 by Elrod](https://discourse.julialang.org/t/how-to-create-a-random-uniform-distribution-between-but-excluding-0-and-10/21908/21), which leads to the analogous solution:
```julia
prevfloat(6.0) * (1 - rand()) - 3
```
for generating random numbers uniformly for floating-point values in the open interval `(-3,3)`.
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### Author:  [@Bob\_Bass](https://discourse.julialang.org/u/Bob_Bass)
#### Post date: [March 10, 2022, 9:43pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719/4 "2022-03-10T21:43:45Z")
Thank you, Marc!
That would have taken me _at least_ forever to figure out. 😁
Gonna go with Steven’s solution; thank you nonetheless!
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### Author:  [@Bob\_Bass](https://discourse.julialang.org/u/Bob_Bass)
#### Post date: [March 10, 2022, 9:48pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719/5 "2022-03-10T21:48:14Z")
Thank you, Steven.
I didn’t see your answer before thanking Marc for a solution, lol.
I’m going to go with your solution on faith for now, until I am more adept with Julia.
Thank you.
EDIT: Actually, I recall reading about prevfloat() somewhere and your solution makes clear sense now.
Thanks again.
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### Author:  [@StevenSiew](https://discourse.julialang.org/u/StevenSiew)
#### Post date: [March 10, 2022, 9:54pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719/6 "2022-03-10T21:54:50Z")
How to get random number between
small \< x \< large
```julia
julia> small=-3.0
-3.0
julia> large=3.0
3.0
julia> prevfloat(large - small) * (1 - rand()) + small
-0.10856055483983429
```
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### Author:  [@Bob\_Bass](https://discourse.julialang.org/u/Bob_Bass)
#### Post date: [March 10, 2022, 10:02pm UTC](https://discourse.julialang.org/t/generate-a-random-number-exclusive-on-both-sides-smaller-x-larger/77719/7 "2022-03-10T22:02:53Z")
Thank you, StevenSiew.
From stevengj’s answer, my perspective was: excluding the minimum via (1-rand()) and excluding the maximum via prevfloat(6.0) and then adjusting the final output by subtracting the midway value.
However I do appreciate your formulaic presentation for it’s clarity, so I will mark your response as the solution for future seekers…