« previous next »
Pages: [1]   Go Down

Author Topic: Interval arithmetic questions  (Read 4415 times)

0 Members and 3 Guests are viewing this topic.

Offline harold

  • LV5 Advanced (Next: 300)
  • *****
  • Posts: 226
  • Rating: +41/-3
    • View Profile
Interval arithmetic questions
« on: August 07, 2011, 12:07:34 pm »
I'm doing some interval arithmetic, and I can't seem to find the answer to this:

When adding two intervals where one of them is empty, what is the result?
For example, [a, b] + {} =
  • empty
  • [a, b]
  • undefined
  • ????
Logged
Blog about bitmath: bitmath.blogspot.nl
Check the haroldbot thread for the supported commands and syntax.
You can use haroldbot from this website.

Offline ben_g

  • Hey cool I can set a custom title now :)
  • LV9 Veteran (Next: 1337)
  • *********
  • Posts: 1002
  • Rating: +125/-4
  • Asm noob
    • View Profile
    • Our programmer's team: GameCommandoSquad
Re: Interval arithmetic questions
« Reply #1 on: August 07, 2011, 02:23:08 pm »
I think the result would be ERR:DIM MISMATCH, so it's undefined.
Logged
My projects
 - The Lost Survivors (Unreal Engine) ACTIVE [GameCommandoSquad main project]
 - Oxo, with single-calc multiplayer and AI (axe) RELEASED (screenshot) (topic)
 - An android version of oxo (java)  ACTIVE
 - A 3D collision detection library (axe) RELEASED! (topic)(screenshot)(more recent screenshot)(screenshot of it being used in a tilemapper)
Spoiler For inactive:
- A first person shooter with a polygon-based 3d engine. (z80, will probably be recoded in axe using GLib) ON HOLD (screenshot)
 - A java MORPG. (pc) DEEP COMA(read more)(screenshot)
 - a minecraft game in axe DEAD (source code available)
 - a 3D racing game (axe) ON HOLD (outdated screenshot of asm version)

This signature was last updated on 20/04/2015 and may be outdated

Offline fb39ca4

  • LV10 31337 u53r (Next: 2000)
  • **********
  • Posts: 1749
  • Rating: +60/-3
    • View Profile
Re: Interval arithmetic questions
« Reply #2 on: August 07, 2011, 02:26:16 pm »
These aren't matrices, but I also think it is undefined.
Interval addition is defined as [a,b]+[c,d]=[a+b,c+d], and since c and d are undefined, [a+undefined,b+undefined], would be [undefined, undefined] or just undefined.
Logged

Offline Horrowind

  • LV2 Member (Next: 40)
  • **
  • Posts: 25
  • Rating: +6/-0
    • View Profile
Re: Interval arithmetic questions
« Reply #3 on: August 07, 2011, 02:56:31 pm »
to rephrase the t0xic_kitt3ns statement: there is no empty intervall, {} is the empty set, and therefore can not be added to an intervall.
Logged

Offline AngelFish

  • Is this my custom title?
  • Administrator
  • LV12 Extreme Poster (Next: 5000)
  • ************
  • Posts: 3242
  • Rating: +270/-27
  • I'm a Fishbot
    • View Profile
Re: Interval arithmetic questions
« Reply #4 on: August 07, 2011, 03:40:12 pm »
It depends on what you're asking. If you're asking how to add the null set to an interval, it's undefined. If you're asking how to add an interval equivalent to ]a,a[, then the answer is that the interval remains unchanged.
Logged
∂²Ψ    -(2m(V(x)-E)Ψ
---  = -------------
∂x²        ℏ²Ψ

Offline harold

  • LV5 Advanced (Next: 300)
  • *****
  • Posts: 226
  • Rating: +41/-3
    • View Profile
Re: Interval arithmetic questions
« Reply #5 on: August 07, 2011, 03:53:40 pm »
ok thanks, it looks like it's undefined
shortly after making the first post I changed the algorithm somewhat so that it will never have to attempt interval addition where one is the empty interval, so I don't really need this anymore, but thanks anyway
Logged
Blog about bitmath: bitmath.blogspot.nl
Check the haroldbot thread for the supported commands and syntax.
You can use haroldbot from this website.
Pages: [1]   Go Up
« previous next »