1waffle1
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| Joined: 16 Oct 2007 |
| Total Posts: 16381 |
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| 26 Oct 2011 07:27 PM |
I'm messing around with some conjectures, and since Roblox throws a tantrum when you have numbers larger than 2,147,483,647, I made something that adds strings. So you can add like 20395832095820469832 and 2092385906824096 and get a real answer. I just made this in like five minutes, but it seems pretty useful.
function Add(a, b) a, b = string.reverse(a), string.reverse(b) local A, B = {}, {} for x = 1, #a do table.insert(A, tonumber(a:sub(x,x))) end for y = 1, #b do table.insert(B, tonumber(b:sub(y,y))) end local numA = #A for i = 1, #B do A[i] = (A[i] or 0) + B[i] end local ok = false repeat ok = true for i = 1, #A do if A[i] > 9 then ok = false A[i+1] = (A[i+1] or 0) + 1 A[i] = A[i] - 10 end end until ok return string.reverse(table.concat(A)) end |
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1waffle1
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| Joined: 16 Oct 2007 |
| Total Posts: 16381 |
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| 26 Oct 2011 07:29 PM |
| bcuz 44562665878976437622437848976653870388884783662598425855963436955852489526638748888307835667984873422673467987856626544 is not a Lychrel number. |
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LocalChum
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| Joined: 04 Mar 2011 |
| Total Posts: 6906 |
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| 26 Oct 2011 07:31 PM |
arent lua numbers all 64 bit doubles
so they can hold liek 10^306 or something
right?
:l |
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1waffle1
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| Joined: 16 Oct 2007 |
| Total Posts: 16381 |
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| 26 Oct 2011 07:35 PM |
this can make numbers even BIGGER than that. but, problem 10 + 01 = 10 false. :( |
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1waffle1
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| Joined: 16 Oct 2007 |
| Total Posts: 16381 |
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pwnedu46
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| Joined: 23 May 2009 |
| Total Posts: 7534 |
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| 26 Oct 2011 08:00 PM |
*tracks thread*
imma make one to subtract, multiply, and divide ^_^ |
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| 26 Oct 2011 08:01 PM |
subtract == make one negative
Tack on the negative thang.
~+[CROOKITY BANDED SNAKES]+~ |
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pwnedu46
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| Joined: 23 May 2009 |
| Total Posts: 7534 |
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| 26 Oct 2011 08:10 PM |
@Popin: I thought that was obvious. :3
function Subtract(a, b) a, b = string.reverse(a), string.reverse(b) local A, B = {}, {} for x = 1, #a do table.insert(A, tonumber(a:sub(x,x))) end for y = 1, #b do table.insert(B, tonumber(b:sub(y,y))) end local numA = #A for i = 1, #B do A[i] = (A[i] or 0) - B[i] end local ok = false repeat ok = true for i = 1, #A do if A[i] > 9 then ok = false A[i+1] = (A[i+1] or 0) + 1 A[i] = A[i] - 10 end end until ok return string.reverse(table.concat(A)) end
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print(Subtract(9999,1)) > 9998 |
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pwnedu46
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| Joined: 23 May 2009 |
| Total Posts: 7534 |
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| 26 Oct 2011 08:12 PM |
@Popin: I found it easier to simply change
A[i] = (A[i] or 0) + B[i]
to
A[i] = (A[i] or 0) - B[i]
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| 26 Oct 2011 08:15 PM |
Here's the easy way to subtract:
function Subtract(a, b) return add(a, -b) end |
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| 26 Oct 2011 08:37 PM |
| OMG! I've been debating whether to make this or not because most languages suck when it comes to handling numerical data. Of course, this wastes more memory... |
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1waffle1
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| Joined: 16 Oct 2007 |
| Total Posts: 16381 |
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GoldenUrg
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| Joined: 23 Aug 2009 |
| Total Posts: 6428 |
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| 26 Oct 2011 09:29 PM |
I don't see why Lua would complain about numbers larger than "max int". Maybe you're trying to put it into an int property?
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| 27 Oct 2011 05:20 AM |
@Golden
Numbers higher than the maximum are automatically set to the maximum.
This is the reason that Julien's code wouldn't work.
~+[CROOKITY BANDED SNAKES]+~ |
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| 27 Oct 2011 05:20 AM |
the reason why*
~+[CROOKITY BANDED SNAKES]+~ |
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| 27 Oct 2011 07:05 AM |
| the roblox 64 bit doubles cant hold a number of size 2^9001, they hold a number something like... lets say 2^51 because that sounds close, and then they scale it so its close to what you want but it still cant hold accurate numbers up to 2^9001 |
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booing
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| Joined: 04 May 2009 |
| Total Posts: 6594 |
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arundel
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| Joined: 21 Apr 2008 |
| Total Posts: 5762 |
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| 27 Oct 2011 10:42 AM |
| Only equal to or above 2^1024 will be the limit... which is quiet big still. But I get the number into a string concept for VERY large numbers. |
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1waffle1
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| Joined: 16 Oct 2007 |
| Total Posts: 16381 |
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| 27 Oct 2011 11:20 AM |
Okay, look at it like this. If you do...
1429685792379857293857923587298375985734967592387 + 9732876529835789678943798273598749683746
You get 1.42968579e49.
Notice how it's missing FORTY DIGITS? It just rounded the entire equation to the ninth digit. Now the number is even SMALLER. |
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pwnedu46
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| Joined: 23 May 2009 |
| Total Posts: 7534 |
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| 27 Oct 2011 03:19 PM |
"long int a; "
No, I win... long long ago; // in a galaxy far, far away.
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pwnedu46
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| Joined: 23 May 2009 |
| Total Posts: 7534 |
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| 27 Oct 2011 03:29 PM |
"Of course, this wastes more memory..."
We're talking about a maximum difference of few KB, depending on the program. Any decent computer today has >= 2GB RAM. Because of that, you don't have to worry about memory management. If you use that in a program that even comes close to threatening to exceed the amount of RAM, you should have already been doing garbage collection.
The execution time to do basic mathematical operations will be (slightly) greater, but it's not a significant (or even noticeable) difference between execution times. |
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HotThoth
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| Joined: 24 Aug 2010 |
| Total Posts: 1176 |
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| 27 Oct 2011 05:50 PM |
| As for that example, wafflez-- you gotta remember that the version that it *prints* isn't necessarily as accurate as what it actually has stored in memory. So if it prints 1.42968579e49, it may still be storing more digits, but just (for the sake of people who don't want to read ~40 more digits) not printing them. You should try adding 9732876529835789678943798273598749683746 tons of times and see if the number eventually goes up. |
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LocalChum
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| Joined: 04 Mar 2011 |
| Total Posts: 6906 |
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