23:14 < matches> And now I am basically adding random lines of code and running the tester and seeing if it still works :S
--- Day changed Fri Sep 12 2014
00:15 < matches> This reminds me of the James Micken comment about addition and multiplication basically being the same thing...
+01:19 < matches> Oh my goodness
+01:19 < matches> I think ParanoidNumber just worked for one very specific case!
+01:19 < matches> ParanoidNumber: 0.3 + 0.3 + 0.3 = 9/10, ToDouble() -> 0.9000000000000000222044604925031308084726
+01:20 < matches> double: 0.3 + 0.3 + 0.3 = 0.9000000000000001332267629550187848508358
+01:20 < matches> And strtod("0.9") = 0.9000000000000000222044604925031308084726
+01:23 < matches> For 0.2+0.2+0.3 = 7/10 it has an error of 1e-16 compared to doubles which apparently have no error
+01:24 < matches> But as floats it has an error of 1e-8 compared to 4e-8
+01:24 < matches> Hmm, why does 7.0 / 10.0 give a bigger error than 0.2 + 0.2 + 0.3
+01:24 < matches> Oh
+01:24 < matches> It'll be denormals probably
+01:25 < matches> That is... quiet irritating
+01:27 < matches> So... it is sometimes better than a float but only if there is a full moon and you sacrifice thrice the number of one tenth of unity goats three times
+01:28 < matches> The other times it breaks because subtraction is totally FITH
+01:29 < matches> Oh, it should be able to do 1/3 + 1/3 + 1/3 except my calculator tester doesn't allow me to enter non decimal numbers
+01:32 < matches> I think 0.3+0.3+0.3 is the only thing it can do better than regular floats
+01:32 < matches> Woo
+01:40 < matches> Ah it is better at beating doubles when it is using doubles as the digit type
+01:40 < matches> But it still is sometimes worse if you have a small number of operations
+01:40 < matches> Probably because one division is less precise than several additions
+01:42 < matches> I'm going to keep telling myself that this is useful
+01:42 < matches> After I sleep
+01:51 < Pommers> It isn't currently a full moon...
+01:51 < Pommers> Also
+01:51 < Pommers> Go to bed
+11:27 < matches> It was a full moon after I sacrificed the goats
+11:40 < Pommers> Stop toying with space matches
+--- Day changed Sat Sep 13 2014
+09:25 < unmercifulfish> I feel that the logs for this chat should just be added to qdb
+09:25 < unmercifulfish> < matches> It was a full moon after I sacrificed the goats
+12:36 < Pommers> Should make a QDB bot for submitting them
+16:20 < matches> When sulix is awarded the nobel prize for his work on quad trees, I will be proud to be a part of this channel
+16:21 < Pommers> Until then you won't be?
+16:23 < matches> I've been thinking of adding a "grep -v matches" before the automatic log commit
+17:45 < matches> I am a horrible person
+17:45 < matches> I am exploiting that "delete" acting on a NULL pointer has no effect
+17:46 < matches> "delete Operation(new ParanoidNumber(a), ADD)"
+17:47 < matches> Where Operation will either return the first argument or NULL
+17:50 < matches> At the moment I'm very pleased with how cleverly I am about to shoot myself in the foot
+17:50 < matches> We'll see how I feel after I pull the trigger
+17:53 < matches> I have either written an extremely elegant or an extremely segfaulting function
+17:57 < matches> The latter is looking more and more likely
+17:57 < matches> But I'm sure there is beauty underneath
+17:57 < matches> Like the ugly duckling!
+17:59 < matches> There's still hope, it turns out I'm segfaulting way before I even get to that
+18:01 < matches> Apparently 2+1 is 6, but doubles think 2+1 is 5
+18:02 < matches> "Freedom is the freedom to say 2+2=4, if that is granted, all else follows"
+18:06 < matches> Ok, 1 + 1 is 2
+18:06 < matches> I think we can call that a result
+18:06 < matches> Write the thesis and we're done here
+22:18 < matches> 1 + 0.3 = 13/10 and 13/10 + 0.2 = Segfault
+22:18 < matches> Getting close
+22:19 < matches> Now I'm doomed to not sleep until it works because I'm never going to remember how this works
+22:20 < Pommers> Got a whiteboard?
+22:20 < matches> I do actually but it's in the other room
+22:20 < matches> And it does not have space for this
+22:22 < matches> I don't think I've ever used so many delete operators...
+22:23 < matches> Also constructing a 4 diretional list on the stack then stealing one of the branches
+22:23 < matches> It's a game of "dodge the double delete!"
+22:24 < matches> Which reminds me, we have copious memory leaks in an external library
+22:24 < matches> 'ld' ?
+22:25 < matches> /lib/x86_64-linux-gnu/ld-2.19.so
+22:25 < matches> Not sure if that's something I'm doing wrong
+22:26 < matches> Turns out you can't pipe valgrind's output to less
+--- Day changed Sun Sep 14 2014
+18:23 < matches> http://szmoore.net/ipdf/sam/abstract.txt
+18:24 < matches> You know
+18:24 < matches> It sounds a lot more boring than it has been
+18:24 < matches> I also need a title
+18:24 < matches> "Number Representations and Precision in Vector Graphics" ?
+18:24 < matches> I'm too scared to pick something punny...
+18:26 < matches> Libreoffice thinks that is 147 words and pluma thinks it is 150...
+18:26 < matches> Oh
+18:26 < matches> hyphenated IEEE-754
+18:28 < matches> I think the first sentence could probably be less mind numbingly boring
+18:28 < matches> My last thesis started with "In this project" which seems terribly not academic
+18:29 < matches> (Every time I read that thesis I get a little more convinced that the markers didn't actually read any of it)
+18:29 < matches> ParanoidNumbers are not going well
+18:30 < matches> Like, it's hard to debug where things go wrong when you have a list like this:
+18:30 < matches> debug: main (tests/paranoidcalculator.cpp:75) - a is: {3*(23*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/100000+(2/1e+06+(2/1e+07+(3/1e+08)))))))))+(3*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/100000+(2/1e+06+(2/1e+07+(3/1e+08)))))))))/10+(4*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/100000+(2/1e+06+(2/1e+07+(3/1e+08)))))))))/100+(1*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/100000+(2/1e+06+(2/1e+07+(3/1e+08)))))))))/1000+(2*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/100000+(2/1e+06+(2/1e+07+(3/1e+08)))))))))/10000+(3*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/100000+(2/1e+06+(2/1e+07+(3/1e+08)))))))))/100000))))))/10+(1*(23*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/100000+(2/1e+06+(2/1e+07+(3/1e+08)))))))))+(3*(398123+(1/10+(2/100+(3/1000+(5/10000+(1/1 ...
+18:31 < matches> That's without simplifying it
+18:31 < matches> But when it gives the wrong results before you even simplify it, that's bad
+18:32 < matches> I'm preeety sure it's not just giving the wrong results because it has a stupid number of terms/factors
+18:32 < matches> It's wrong enough that there's an extra factor or a factor missing or I don't even
+18:34 < matches> Hmm
+18:34 < matches> I want to add "Unlike paper, ..." before the third sentence
+18:34 < matches> I'm going to Captain Obvious
+18:38 < matches> :(
+18:38 < matches> Panic mode is well and truly activated now
git.ucc.asn.au / ipdf / documents.git / blobdiff
UCC git Repository :: git.ucc.asn.au