# IRC log for #rosettacode, 2012-01-10

All times shown according to UTC.

Time Nick Message
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02:21 TimToady note that only my first solution was *not* streaming :)
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19:00 mikemol Just got an email from someone who had success using an old script I wrote.
19:00 mikemol Any idea what this is? I'm not sure 'triangulation' is the right term, but I didn't know a better one when I wrote it: http://code.google.com/p/triangulate​/source/browse/trunk/triangulate.php
19:00 fedaykin "triangulate.php - triangulate - A multidimensional triangulation algorithm and PHP implementation - Google Project Hosting" http://rldn.net/56I
19:05 mwn3d_phone Is there a picture to go along with that?
19:09 mikemol No
19:10 mikemol Though if it helps, you can take "n-sphere" and make it "line segment", "filled circle" or "filled sphere", depending on if you want to think in one, two or three dimensions.
19:10 eMBee in a simplified example, if you have two overlapping circles, you create a new circle that passes through the two points where the original circles intersect?
19:10 mikemol Sounds familiar. I think so, yes.
19:11 * eMBee seemed to have not problem underatanding the description, but he has no idea how that is called
19:11 mikemol Well, more precisely, add that the circle's diameter is the distance between those two points.
19:11 eMBee right
19:13 mikemol Wrote it for my brother, who at the time was hunting something in Eve Online where he could know how far away something was, but was never told in which direction it lay.
19:15 eMBee does earthquake triangulation work that way? http://www.qrg.northwestern.edu/projects/vss/​docs/navigation/1-what-is-triangulation.html
19:15 fedaykin "What is triangulation?" http://rldn.net/9NJi
19:15 opticron lol
19:16 opticron that's awesome
19:16 * opticron links that to his friend that plays eve
19:17 mikemol Apparently, my brother never got it to work.
19:17 mikemol >.>
19:17 mikemol But some guy in Mexico was able to use it and cell tower data to locate himself.
19:18 opticron impressive
19:19 mikemol You know you've been watching too much Doctor Who when you see an illustration of an astronomy observation telescope and think, "what's a Dalek doing on a page about triangulation?"
19:19 eMBee lol
19:20 eMBee that's advanced information ;-)
19:20 mikemol Also woke up this morning hearing a TARDIS several times, but it was trucks passing on the nearby freeway.
19:21 mikemol Anyway, the earthquate triangulation page looks like it's a far more precise method.
19:23 eMBee well, speaking of waking up, i better go to sleep if i want to catch breakfast in a waking state...
19:27 eMBee this looks like it is related too: http://en.wikipedia.org/wiki/Multilateration
19:27 fedaykin "Multilateration - Wikipedia, the free encyclopedia"
19:28 eMBee http://en.wikipedia.org/wiki/Trilateration
19:28 fedaykin "Trilateration - Wikipedia, the free encyclopedia"
19:29 mikemol Yeah, looks like trilateration is it.
19:30 eMBee sounds like a task for rc :-)
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20:09 GlitchMr Weird... I have noticed that in JS regexpes [^] is this same thing as [\s\S]... it might be useful to shorten my regular expressions...
20:11 GlitchMr But for example, Perl doesn't work this way... it considers "]" to be part of character group...
20:11 GlitchMr Regular expression engines are... weird...
20:17 mwn3d_phone So does "[^]" mean "not nothing"?
20:17 GlitchMr Yes
20:17 GlitchMr It looks like a candle.
20:18 mwn3d_phone Does [.]+ work for that too?
20:19 GlitchMr No...
20:19 GlitchMr It means one dot character or more
20:19 GlitchMr I actually like this escaping style... I usually use it instead of slashes
20:19 mwn3d_phone I'm basing that off of javas pattern class
20:19 GlitchMr [.] is this same thing as \.
20:19 mwn3d_phone Where "." means "any one character"
20:20 GlitchMr Yes, but not in character groups
20:20 GlitchMr Also, in normal language you would just use /s modifier, but not in JS. JS just doesn't have /s modifier.
20:20 GlitchMr So I've found [^] interesting alternative to it...
20:21 mikemol O.o
20:21 mwn3d_phone It looks like in java ^ is also "the beginning of a line"
20:21 mikemol LibreOffice insists on opening a .txt file as a spreadsheet import.
20:22 GlitchMr mwn3d_phone, yes
20:22 GlitchMr But in character groups (as long it's first character) it means any characters which aren't on list.
20:22 GlitchMr The list is empty...
20:22 GlitchMr I'm surprised that even works. It doesn't in Perl for example...
20:23 GlitchMr But then, /[/]/ works in JS and doesn't in Perl (unless you would change delimiters... but it's not possible in JS...)
20:26 GlitchMr EcmaScript regular expression engine is pretty tricky and weird...
20:27 mikemol It sounds like you're examining two separate issues...parsing and semantics.
20:28 mikemol I mean, even if you couldn't change delimiters, you could use string interpolation to achieve the same ends.
20:29 GlitchMr It also lacks features...
20:30 GlitchMr (?<=not in EcmaScript)
20:30 GlitchMr (this is positive lookbehind BTW)
20:30 GlitchMr It's useful in certain cases
20:31 mikemol And that's a semantic issue, sure. I was just triggering on the /[/]/ case. Though I imagine requiring that syntax to be supported is a PITA for implementors.
20:32 mikemol Then again, maybe not, if you don't need a clear distinction between regex parsing errors and general parsing errors.
20:33 GlitchMr Regular expressions are normal part of grammar... I would say it's bigger part of grammar than for example in Perl...
20:33 GlitchMr That could explain this /[/]/...
20:33 GlitchMr In Perl, regular expressions are just normal strings which are parsed just in time...
20:35 GlitchMr DB<18> qr/:)/
20:35 GlitchMr Unmatched ) in regex; marked by <-- HERE in m/:) <-- HERE /
20:35 GlitchMr Or maybe not...
20:39 GlitchMr http://ecma262-5.com/ELS5_Section_7.htm#Section_7.8.5