Zugg Software :: View topic - Numerical Sorting

Sorcerer Joined: 13 Jan 2006 Posts: 715

Well, recently I wrote a script that needed to take a string list with all numerical values in zMUD and sort them out into proper order.
zMUD does not have a function to do this, as %sort() returns 10, 100, 4, 500.... etc etc...
So, I figured it would be nice if CMUD DID have such a function, since it is relatively simple.
I mean, it's a TINY little bit of code that could even be included in the next beta if Zugg felt like it.
Though, unlike my alias it should have a little error checking built in, just in case the list variable does not contain all numbers... Or treat all non-numeric params as 0.

Here is the alias I made in zMUD to do the same job:

Wanderer Joined: 09 Jun 2006 Posts: 62 Location: Florida

For the sake of speed / efficiency, wouldn't it make more sense to use local variables to hold the number of items for the loop and the temp as well? Not trying to be critical, just "thinking out loud" about a few ways this could be enhanced as a temporary solution. :)

Posted: Tue Dec 11, 2007 9:58 am

It'd be better, really, if sorting a variable did this automatically. There are very few cases where you'd mind 110 coming before 1050.

Wizard Joined: 03 Mar 2001 Posts: 1127 Location: London

What would sort do if the list was
110|1050|a|b

does it treat them all as strings or sort the numbers as numbers and the strings as string?

Posted: Tue Dec 11, 2007 10:05 am

Doesn't seem very complex to me - the strings that it can coerce into numbers, it does. That's the only way something like this would work.

Posted: Tue Dec 11, 2007 6:47 pm

Sorry, but this isn't as trivial as you'd think and won't be done for the public version. Right now CMUD is using the Sort property of the internal TStrings Delphi data structure. And this uses alphabetic sorting and not numeric sorting.

Sorcerer Joined: 13 Jan 2006 Posts: 715

Sorcerer Joined: 13 Jan 2006 Posts: 715

Posted: Tue Dec 11, 2007 11:46 pm

pseudo code is language specific???

Posted: Tue Dec 11, 2007 11:52 pm

if it is a list of all numbers... just pad the left end with 0's so all the members have the same length

Posted: Wed Dec 12, 2007 12:32 am

Sorcerer Joined: 13 Jan 2006 Posts: 715

Enchanter Joined: 05 Mar 2003 Posts: 593 Location: Canada

We can use lua to do any type of sorting you need for example:

Adept Joined: 04 Feb 2005 Posts: 246

Posted: Wed Jan 30, 2008 6:37 pm

The function argument to table.sort takes two arguments, both of which are items in the list. It should return true when the first argument should go before the second in the list, and false when it should go behind it. You can read more about it in the Lua manual.

Enchanter Joined: 05 Mar 2003 Posts: 593 Location: Canada

I know what you mean about comparison functions usually returning -1,0 or 1 Zhiroc.
I thought the same thing when I first looked at the table.sort method.
If you have a function cmp(f,s) which returns true if the first argument is less than the second.
You can get the equiv of the perl <=> or cmp operators in Lua by doing

Result = cmp(A,B) and -1 or cmp(B,A) and 1 or 0

Its not as nice looking as the perls <=> operator but it does the same thing.
It also demonstrates that we can get all three values with a comparison function returning a boolean value.