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Max Facetime
Apr 18, 2009

well see to a mathematician, like me, numbers exist independent of any computer hardware in a world of pure abstraction, like in a mathematical sense, and what do you mean there's different kinds of numbers?

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Symbolic Butt
Mar 22, 2009

(_!_)
Buglord
real numbers is seriously crazy poo poo

MononcQc
May 29, 2007

let me tell you about complex numbers

Opinion Haver
Apr 9, 2007

the set of numbers that can be computed is countable, and there are uncountably many real numbers

also js and lua probably don't have bigints because bigint arithmetic is slower than float/double arithmetic

Ericadia
Oct 31, 2007

Not A Unicorn
I couldn't imagine

Gazpacho
Jun 18, 2004

by Fluffdaddy
Slippery Tilde
i for one am disappointed that the c++11 committee didn't include a class that exactly represents nth roots, cmon guys do you want to build a world-class language or not?

Zaxxon
Feb 14, 2004

Wir Tanzen Mekanik

yaoi prophet posted:

also js and lua probably don't have bigints because bigint arithmetic is slower than float/double arithmetic

I think the idea is that since these are languages for "small programs" having different numeric types would confuse people. poo poo like: "How come 1/2 doesn't equal .5"

I mean, it's a bullshit reason, but that's what I think was going on at the time.

Base Emitter
Apr 1, 2012

?

Zaxxon posted:

I think the idea is that since these are languages for "small programs" having different numeric types would confuse people. poo poo like: "How come 1/2 doesn't equal .5"

I mean, it's a bullshit reason, but that's what I think was going on at the time.

More like they're supposed to be type-free, so having two different kinds of 1 is sort of contradictory. 1 and "1" is bad enough already.

Sniep
Mar 28, 2004

All I needed was that fatty blunt...



King of Breakfast

rotor posted:

WHAT THE gently caress IS A MEZZANINE

a massive attack album

PENETRATION TESTS
Dec 26, 2011

built upon dope and vice
it's an entresol

Nomnom Cookie
Aug 30, 2009



yaoi prophet posted:

the set of numbers that can be computed is countable, and there are uncountably many real numbers

also js and lua probably don't have bigints because bigint arithmetic is slower than float/double arithmetic

do you have a proof handy for that bc it does;t seem obvious to me

Opinion Haver
Apr 9, 2007

Nomnom Cookie posted:

do you have a proof handy for that bc it does;t seem obvious to me

fix some language L (with a finite alphabet) to do your computation in. if a number is computable, it can be computed by some program of finite length in L, by definition. so there are as many computable numbers as there are finite programs in L, which is countable (since you can just enumerate the length 1 programs, the length 2 programs, etc.)

FamDav
Mar 29, 2008
this is boring lets discuss how signed integer arithmetic is just constrained 2-adic arithmetic.

tef
May 30, 2004

-> some l-system crap ->

Nomnom Cookie posted:

do you have a proof handy for that bc it does;t seem obvious to me

CANTORS DIAGNONAL POSTING

tef
May 30, 2004

-> some l-system crap ->
let's ignore all the numbers and just look at the ones between 0 and 1

they're obviously countable, so let's put them in a list

then, hang on,

couldn't i make a new number

for each digit, I go to that number in the list and make sure the digit is different

it's a big, long number, but now it's totally not in the list I made

how can this be

maybe I can't put them in a list, like I can the integers.


time works the same way

tef
May 30, 2004

-> some l-system crap ->
ps. all the fractions can be put in a list



also, if there are infinitely many trancidental numbers why can people only name two?

FamDav
Mar 29, 2008

tef posted:

CANTORS DIAGNONAL POSTING

mods make this my name tia

also there's a little extra rigor involved in making sure you generate a new number and not just an alternative representation of another number, which is really just making sure you never pick an infinite string of 9's

tef
May 30, 2004

-> some l-system crap ->
but 1 = 0.99999999999999............

tef
May 30, 2004

-> some l-system crap ->
i did say 'let's put all the numbers in a list', not 'let's make a list of all the numbers, with duplicates' :q:

Blotto Skorzany
Nov 7, 2008

He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip
there are infinitely many transcendental numbers?

Nomnom Cookie
Aug 30, 2009



yaoi prophet posted:

fix some language L (with a finite alphabet) to do your computation in. if a number is computable, it can be computed by some program of finite length in L, by definition. so there are as many computable numbers as there are finite programs in L, which is countable (since you can just enumerate the length 1 programs, the length 2 programs, etc.)

durr i shouldve seen that

FamDav
Mar 29, 2008

tef posted:

but 1 = 0.99999999999999............

yeah exactly so if i never wrote down 0.9... and that's what i came up with as my new number and i already had 1 there'd be egg on my face

also the fact that even though the rational numbers are countable they are dense in the real line

also you can generate a subset of [0,1] that has infinitely many points but has zero length

also you can actually split apart a sphere in a certain way to generate two spheres of the same size

also (real analysis 101 fact)

FamDav
Mar 29, 2008

Otto Skorzeny posted:

there are infinitely many transcendental numbers?

yes. there are countably infinite algebraic numbers so there must be uncountably infinite transcendental numbers


lol

Nomnom Cookie
Aug 30, 2009



tef posted:

ps. all the fractions can be put in a list



also, if there are infinitely many trancidental numbers why can people only name two?

bc no one cares about the other ones

tef
May 30, 2004

-> some l-system crap ->

Otto Skorzeny posted:

there are infinitely many transcendental numbers?

yes.

the natural numbers, the integers, the algebraic numbers and the computable numbers are countable.

when you take that all away, you're left with transcendental numbers. iirc.

and you can't put them in a list

Toady
Jan 12, 2009

tef
May 30, 2004

-> some l-system crap ->
CALKINS WILF SEQUENCE


q' = 1/(2*floor(q)-q+1)

Blotto Skorzany
Nov 7, 2008

He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip

FamDav posted:

also you can actually split apart a sphere in a certain way to generate two spheres of the same size

iff the "axiom" of choice is true, which it isn't, and even then the "spheres" aren't actual spheres (have no surface area) iirc

Blotto Skorzany
Nov 7, 2008

He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip
georg cantor did 9/11

tef
May 30, 2004

-> some l-system crap ->
what's an anagram of banach-tarsky?

:q:

Sneaking Mission
Nov 11, 2008

Crab Hat Yanks

Blotto Skorzany
Nov 7, 2008

He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip
bays crank hat

Blotto Skorzany
Nov 7, 2008

He's a PSoC, loose and runnin'
came the whisper from each lip
And he's here to do some business with
the bad ADC on his chip
bad ADC on his chiiiiip
more like BAYES' CRUNK HAT imo

tef
May 30, 2004

-> some l-system crap ->

Sneaking Mission posted:

Crab Hat Yanks


Sneaking Mission posted:

Crab Hat Yanks

FamDav
Mar 29, 2008

Otto Skorzeny posted:

iff the "axiom" of choice is true, which it isn't, and even then the "spheres" aren't actual spheres (have no surface area) iirc

define truth for an axiom

FamDav fucked around with this message at 04:49 on Feb 11, 2013

Janitor Prime
Jan 22, 2004

PC LOAD LETTER

What da fuck does that mean

Fun Shoe

tef posted:

maybe I can't put them in a list, like I can the integers.

How can you put all the integers in a list in the first place if its infinite? I know this is a numbershit 101 for you guys but this just doesn't seem intuitive at all to me

Opinion Haver
Apr 9, 2007

Otto Skorzeny posted:

iff the "axiom" of choice is true, which it isn't, and even then the "spheres" aren't actual spheres (have no surface area) iirc

no they're completely normal spheres if you do it right (also like famdav said 'truth' of an axiom is kind of a weird thing to talk about)

PENETRATION TESTS
Dec 26, 2011

built upon dope and vice
it's an infinite list

PENETRATION TESTS
Dec 26, 2011

built upon dope and vice
you get as many natural numbers as you want (god's gift)

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FamDav
Mar 29, 2008

Hard NOP Life posted:

How can you put all the integers in a list in the first place if its infinite? I know this is a numbershit 101 for you guys but this just doesn't seem intuitive at all to me

The best way to think about it is that i can match up each number in my set X with one of the numbers in N, i.e. 0,1,2,3,4,5,6,7,8,9,...

For integers ...-2,-1,0,1,2... I can do this by having all the even numbers x map to x/2 and all the odd numbers map to -(x+1)/2.

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