Re^8: Data visualisation.

Nothing, really. It just mentions them.... I'll still calculate the intersection point where the lines *would* meet, were they long enough.

Oh, okay.

Though I have to say that it sounds like you are now performing 3 "triangle inequality" checks for every possible triangle (for my 17 node dataset that is 3*15! or nearly 4 Trillion additions and 4 Trillion comparisons) for no real purpose. Ie pure make-work....

For Dirk80's 24 node dataset, that rises to 1.8 trillion trillion redundant calculations.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

Comment on Re^8: Data visualisation.

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Re^9: Data visualisation. by roboticus (Chancellor) on Jan 05, 2014 at 18:13 UTC
BrowserUk: We're only picking three points for each triangle, and the point order doesn't matter, so the number of calls to chk_triangle_inequality during the exhaustive check for your dataset is n!/((n-3)!3!). For your dataset, it's 680 calls, and 2024 for Dirk80's dataset. If it were trillions of checks, I'd've pressed ^C long before it ended. ;^D Currently the check is pointless busywork, but since TSP problem is interesting to me, and printing interesting clues might spur ideas, so I threw it in for fun. I frequently litter my programs with print statements showing intermediate steps, or call functions whose results may be interesting. I delete it when it proves valueless to me, and then clean it up when I'm through. But I can't always predict beforehand which functions I'll find to be junk. For example, when I was playing with your Bloom filter example, I put various print statements in my program, and noticed that one of the values was approaching an "interesting" value, allowing me to figure out the distributions. Update:* As AM said, wrong formula! Fixed. ...roboticus When your only tool is a hammer, all problems look like your thumb.	[reply]
Re^10: Data visualisation. by Anonymous Monk on Jan 05, 2014 at 18:36 UTC
Strange ... wrong formula but correct values??? s/2/3/ ;-)	[reply]
Re^10: Data visualisation. by BrowserUk (Patriarch) on Jan 05, 2014 at 18:54 UTC
so the number of calls to chk_triangle_inequality during the exhaustive check for your dataset is n!/((n-2)!2!). For your dataset, it's 680 calls, and 2024 for Dirk80's dataset.* Indeed. I found completely the wrong formula. (BTW: it is simply all combinations of 3 from N; so if you have a calculator with an nCr button ... ) With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re^9: Data visualisation. by Anonymous Monk on Jan 05, 2014 at 10:17 UTC
nosense!	[reply]
Re^10: Data visualisation. by BrowserUk (Patriarch) on Jan 05, 2014 at 10:48 UTC
Argh! You're right. For Dirk80's dataset it is only 1.1 billion trillion. My mistake. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re^11: Data visualisation. by Anonymous Monk on Jan 05, 2014 at 10:51 UTC
try again...	[reply]
Re^12: Data visualisation. by Anonymous Monk on Jan 05, 2014 at 11:11 UTC


We don't bite newbies here... much
	PerlMonks