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User: Bradley

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  1. Re:Say It Ain't So on The Real Reason For Microsoft's TomTom Lawsuit · · Score: 1

    and which part of the GPL allows you to do that? Yes, in practice I'm sure that that would happen, but that's not the point.

  2. Re:Say It Ain't So on The Real Reason For Microsoft's TomTom Lawsuit · · Score: 2, Insightful

    What if I'm in the Canada, and buy (from a US company) a GPL program which comes with a written offer to provide the source. Then a month I move to Cuba, and send a letter to the US company asking them to please send me the source (including proof of purchase, and cash to cover costs of copying and sending the source code back to me)

    What does the US company do now?

    I'm not a lawyer, and for all I know US law deals with this sort of situation. But assume that it doesn't (and assume that I can't, for some other reason, distribute the source and binary together)

    Since any of my customers could move to Cuba/etc, I cannot make the promise for written source, so I cannot be sure that I can "satisfy simultaneously [my] obligations under this License and any other pertinent obligations". which means I can't distribute the software at all.

  3. Re:But will they do DVI? on Intel Discrete Graphics Chips Confirmed · · Score: 1

    There SDVO, where you put a cheap card into the PCIe x 16 slot. Graphics goes over the PCIe bus (@1-2GHz) and the SDVO card can then have DVI/HDMI/tvout/etc. You still use a slot, but don't need to have a separate card/heatsink/fan/etc.

    Only problem is that I've never actually seen one.... SiL apparently make chips, and I'm sure if I went looking I could find a card, but they're not exactly common. No idea if they work under linux.

  4. Re:Ignorance is no excuse on E-Voting Problems Are Mostly User Error, Says ITAA · · Score: 1
    What, exactly, does it matter if the counties that Gore wanted a recount in were run by Democrats or the ballot was designed by a Democrat?

    Better question - why, exactly, was any voting run by a member of any party?
  5. Re:I recommend Mysql users to take a look at PG on PostgreSQL 8.0 Enters Beta · · Score: 1

    You have to analyze to get that to change anyway, with postgres, and having analyze invalidate stored plans is probably sensible.

    Postgres does have PREPARE, which speeds things up a lot, although DBI support for it isn't quite there last time I looked, plus it doesn't recalculate the plan when 'stuff' (schema, statistics, etc) change

  6. Re:only two things are certain in life... on US Cell Phone Users Discover SMS Spam · · Score: 2, Informative

    In Australia, local phone calls aren't free, but they're untimed. Calls to mobiles are timed, and thus more expensive.

    However, mobiles have separate area codes to landlines, so its always possible for a caller to know that they're going to be charged more. It also means that you can move across the country and keep the same mobile number...

  7. Re:PostgreSQL has every feature but Replication. on MySQL A Threat to Bigwigs? · · Score: 2, Interesting

    Well, its all very well to claim speed, but its not always true. Yes, MyIASM is (generally) quicker than postgres.. The problem is that innodb is really slow.

    For example, imagine that I have a bugs database (which I do; its called Bugzilla). I want to find all bugs where I'm either the reporter, or I've commented. Since bugs can have zero comments, I need to outer join the busg table to the accounts table. With randomly generated data, and 100,000 bugs, 1,000,000 comments randomly distributed among the comments:

    select distinct bugs.bug_id FROM bugs LEFT JOIN longdescs USING(bug_id) WHERE (bugs.assigned_to=86 OR longdescs.who=86);

    mysql: 3.33 sec
    postgres: 14423.07 msec [I can get this down to 11758.74 msec by changing a
    config option - I should probably file a bug on that]

    (returning 46 rows)

    But the thing is that I just want bug numbers. I don't care how many times I've commented, or need to know the contents of the comments. What I really wanted to ask was:

    > SELECT bugs.bug_id FROM bugs WHERE bugs.assigned_to=86 OR bugs.bug_id
    IN (SELECT bug_id FROM longdescs WHERE longdescs.who=86)

    mysql: error
    postgres: 137.66 msec

    (To be fair, this does need CVS-postgres to be fast. It is, however, possible to create a UNION join to make it much faster, arround 6ms. Thats not appropriate for the generated SQL bugzilla uses, and having the db do the transformation from teh LEFT JOIN requires knowleges of the distinctiveness of bugs.bug_id, and the distinct in the original query, so its not trivial)

    Oh, and it took almost 2 minutes with innodb. I will admit to not having tuned the various innodb parameters, plus this was 3.23, so I'm sort of ignoring that.

    Queries are often slower, too - as far as I can see, mysql doesn't produce a query tree, but rather a list. If you only have one table, then this doesn't matter, but if you start doing complex joins (and without subselects, you do that more often than you may want to) then it does make a difference. Yes, I know that mysql has subselects in the development version. I'd be interested to see if they have the same speed problems as in postgresql I see it as one of the main advantages of MySQL over PostgreSQL is that you are able to turn off transactions if you don't need them.

    You always need transactions. If you think that you don't, then its obviously not important to you if your data gets lost. (You also want foreign keys and constraints, but....) And whilst I don't know too many 'bigwigs', I'm pretty certain that most of them want half of their commited data to not vanish if there's a power failure.

    Now, I'm certainly not saying that postgres is always better than mysql, and I'm sure that people can come up with similar examples to the above, but where postgres sucks and mysql blows it away.

  8. Re:Dropping Columns finally supported on PostgreSQL 7.3 Released · · Score: 2
    Good greif, that's cool! Do a whole database transformation in a transaction, and if it borks out, it rolls back? Cool!

    Yeah, it is cool. The side effect, of course, is that the space from DROP COLUMN can't be automaticaly reclaimed - for that you need to run a VACCUM FULL, which does need an exclusive lock. You can batch updates, however, and then do the vaccum at some time in the future when the db isn't being heavily used (ie 3am on a public holiday)

    Newly added rows don't have much overhead for the dropped columns though, apparently. The postgresql websties are still pointing to 7.2 docs, but 7.3 says:

    "The DROP COLUMN command does not physically remove the column, but simply makes it invisible to SQL operations. Subsequent inserts and updates of the table will store a NULL for the column. Thus, dropping a column is quick but it will not immediately reduce the on-disk size of your table, as the space occupied by the dropped column is not reclaimed. The space will be reclaimed over time as existing rows are updated. To reclaim the space at once, do a dummy UPDATE of all rows and then vacuum, as in:

    UPDATE table SET col = col;
    VACUUM FULL table;"

  9. Re:Still responsive? on Linux Kernel Bugzilla Launched · · Score: 2

    Slashdot typically links to individual bugs, not to the main page.

    Loading the index page has 0 DB hits if you're not logged in (Well, once an hour it'll run stuff, but....)

    Also, its probably a more powerful machine.

  10. Re:Code Red. on Cable Firms Limit Users' Freedoms · · Score: 2

    Sure, but once you start doing stateful inspection to allow 'things which don't look like http' though, the costs (money + response time) go up, as does the risk of the server getting it wrong.

    Lets face it, the vast majority of port 80 is for http, so why should an ISP care about the other uses?

  11. Re:Code Red. on Cable Firms Limit Users' Freedoms · · Score: 2

    Transparent proxies suck, mainly because they're never truly transparent. My provider tried transparent FTP proxying a couple of days ago, but it seems to be gone now (they tried again last year, and it was gone within a few days, apparently - I was in a differnet country at the time)

    They suck, because I can't use port 80 for non-http connections.

    They suck, because occasionally you'll get out of date pages, and have to shift-reload.

    They suck, because sometimes pags will just stop half way through. OK, that ones an implementation detail, but two different ISPs on different sides of the world (.AU and .CA) running different proxy servers have done that to me. Usually only for a few days at a time, then its fine for another month, but....

    They suck, because my current one doesn't seem to want to do persistent connections some of the time.

  12. Re:Are you ready for some REAL SPEED? on Mozilla Tree Closes for 1.0 · · Score: 1

    That pref doesn't actually do anything at the moment....

  13. Re:Please enlighten me re: "tabbed browsing"... on Google's Weakness, AltaVista's Strength · · Score: 2

    Thats a sidebar, not tabbed browsing. Do control-T to open a new tab (or right-click/open in new tab on a link) to get a list of tabs at the top of the window.

  14. Re:ACM Programming Contest on Slashback: 2600, X-Many Bytes, Results · · Score: 2

    Well, problem I was the one that our team submitted with 10 minutes to go, that we ended up getting right. We weren't sure what happened if blocks started up on the bottom of the grid (do they vanish? before or after the next move? Do they count as turns?) so we just submitted it anyway.

    You're probably right for D. But there were plenty of other problems to try :)

    The first test I noticed. The real problem was that given a set of words: AB, CD, AC, BD, then the following was valid (I think)

    ->AB ->AC
    ->CD ->BD

    All the maximal strings more than one character are in the input list. It gets more complicated if you have a 3x3 array like that, because then you can't check to prune after attemptying to allocate each slot - if you allocate line one then line two it will never be right, but if you do line 1 then line 3 then line 2 it may be. So you run into time problems.

    Talking to other teams afterwards, I think they were that picky. I had handled:

    ->AB->CD

    with words ABCD and CD, and checked for adjacent words, but not the other case.

    I misread the instructions, and spent too long trying to work out what case I had missed before I reliased what it meant. My clarification came back "No comment", which hinted that I was right, but I would have had to rewrite bits of my algorithm to get it working, and we were running out of time.

  15. Re:ACM Programming Contest on Slashback: 2600, X-Many Bytes, Results · · Score: 1

    > That's pretty funny. If they had just known a little more theory, they would have known that a comparator network is a sorting network if and only if it correctly sorts all binary strings (i.e., the input alphabet is restricted to two characters). The maximum number of inputs was 12, so that only requires 4096 simulations, instead of 5000.

    Maybe they did, and so their solution was the correct one, and wasn't so funny after all. As I said, it was a rumor that I heard second hand. I certainly didn't know that - our team was a bit weak on the theoretical side. Most of those sort of courses are taught in 4th year for us, which started one week before the competition for one of our team members, and is only next year for the other two. It was the first time USyd had been to the finals, so I think we did reasonably well. I think I saw a couple of teams get H out.

    Note that I didn't say there was no correlation - there obviously is, and I agree that the comps do improve programming skill. But there are good programmers who don't do well in this sort of stuff, and the other way arround as well. The teams that came in the top ten are definately very good programmers. What I was pointing out the the OP was that the fact that the European teams went better than the US teams doesn't necessarily show that American CS graduates can't code.

    For D, thats sort of what we came up with as an idea, but we were worried about the time it may have taken. You have to loop through all the trees until you can't cut any of them down, and if every iteration only enables you to cut down the last one, you have to do this n^2 times as a worst case. (There are shortcurts, but I don't think that they improve thing too much) The maximum number of trees was 100, IIRC, and we weren't told the time limits. Maybe the time limits wren't a problem - we decided to try other questions instead.

    I spent a lot of time on the crossword question - I misread it and missed out on a lot of the edge cases, and never did get it out.

  16. Re:Yowza! on Slashback: 2600, X-Many Bytes, Results · · Score: 1

    Those were for the IBM Visual java challenge, not the main competition. First prize for the actual comp was US$9000, IIRC.

  17. Re:ACM Programming Contest on Slashback: 2600, X-Many Bytes, Results · · Score: 2

    One thing that a couple of people who were there discussed was what sort of relationship there is between going well in these sort of competitions and being a good programmer.

    The competitions require fast, quick hacks, not maintainable solutions. Cut and paste coding works fine.

    For example, one of the problems (H, I think), gave you a network of comparators (two inputs, and two outputs which would return the inputs in sorted order), and asked you if it was a sorting network. (As well as how long the operation took to complete).

    The rumor (which I heard from enough people to believe) was that the Stanford picked n random numbers 5000 times, and simulated the machine. If the simulation showed that the numbers came out sorted for each of these random choices, then their program stated that it was a sorting network. Now the probability that it was not was very very small - I believe their program worked on the first try. And its a clever hack. But its not the sort of thing you'd probably want to do for an open source project.

    Apparently some people got credit for the competition, based on how well they did, and some have solved > 500 past problems (one of the European teams did that - I forget which one, and I heard that secondhand). The more complicated problems can take a lot of time, so thats a lot of effort.

    One other thing is that you can take in any printouts/books/written notes which you want, so if you have them indexed properly then that can be a lot of help. One of the problems was very similar to one which one of the other people on the USyd team has done previously (although it wasn't one that we'd brought with us, unfortunately)

    Also, does anyone who was at the competition know if any team attempted problem D (the trees in the forest problem)? I don't think anyone had before the scoreboard was disabled in the last hour. Was there a nice way to do that (Our team had done almost no computational geometry)?

  18. I was there on Slashback: 2600, X-Many Bytes, Results · · Score: 2

    For coming 11th you get a silver medal. (The medals are done based on how many problems you solve, but the rankings take into account the time you take to do it, as well as any penalties for incorrect submission)

    I was part of the university of Sydney team (although I'm currently at McGill uni in Montreal as part of an exchange program) We got a bronze medal (4 problems solved) - our last one was submitted 10 minutes before the end of the comp, and we didn't know if it was right or not until the award ceremony.

    It was lots of fun. I thought the most amusing bit was when someone came up with the idea of teaching the IBM face recognition software to recognise the face on the side of a pringles container. Mr Pringles is now a registered user on that IBM demo.

    IBM had lots of cool demos of stuff that they are working on - they were the sponsors of the competition. Unfortunately they don't do that sort of R&D in Australia.

    Oh, and is there something wrong with the fact that on the first night the USyd team played (American) Trivial Pursuit with the Berkeley team for relaxation? :)

  19. This is good on U.S. Significantly Lowers Export Limitations · · Score: 5

    I'm an exchange student from australia in .ca now, and I tried to buy a computer from a large online retailer with a credit card with a postal address in Australia. A few hours later I get a phone call. Because I don't live in North America (even though the computer was being delivered to an address in Canada), I had to go through a whole set of export control questions: "Do you intend to use this device for nuclear or biological warfare?", "Do you intend to manufacture chemical weapons with this computer?", etc etc. The person on the other end was very appologetic about it, but still...

    I didn't ask him if anyone ever said yes to those questions.

  20. Re:British money in 1905 on Slashback: Sand, Maps, Antiquities · · Score: 2

    If you want to be pedantic, then you probably couldn't sell it for less than 1/6, or its equivalent value (what would a coin collectior pay for a mint condition 1905 1/6 piece?) Inflation isn't mentioned, so that doesn't count, I suppose.

    Isn't stuff from 1905 out of copyright though, even in the US? That also assumes that that someone is still around to complain.

  21. Mozilla patch available on Bring Back Gopher Campaign · · Score: 3
    I'm going on exchange to McGill University next year, and all the timetables and stuff are in a gopher system. So I wrote a patch for mozilla. Its attached to bug 49334.

    Searches don't work, and you can't use proxies (now I'm finished exams those are the next feature), but the rest of standard gopher works fine.

  22. Re:OFF TOPIC Re:Well, It's probably fair on Coding Classes & Required Development Environments? · · Score: 2
    In theory this is true. In practice there are many quirks in the various virtual machines that make this a tad more problematic than Sun's marketing people will have you believe.

    One of my 1st year courses involved programming in Java. I spent a few hours once chasing down a null pointer exception that crashed on my computer, but worked perfectly on the SunOS machines at uni, and the windows machines of the other people in my group.

    This was multithreaded code, so I spent some time checking for deadlocks caused by the faster speed of my computer. It eventually turned out that another group member had done:

    for(i=0;i<=array.length;i++) { stuff with array[i]; }

    and this worked perfectly on evryone elses system, except on the linux JDK, which ended up a few lines later with a NullPointerException. I never worked out why it didn't give ArrayOutOfBoundException, but hey... I couldn't get a simple test case either, to report the bug.

    Every CS project I've done (I'm in the 2nd semester of 2nd year, doing some 3rd year courses as well) so far has had me finding some bugs in whatever language/compiler/utility library I use. This includes the assembler course, where I managed to get SPIM to misassemble some of the pseudoinstructions.

    Just because it works on one computer doesn't mean that it works everywhere - thats why porting software involves more than typing make.

  23. Re:pentium on Red Hat 7.0 Beta Is Out · · Score: 2
    Also, since we're using gcc 2.96

    I presume thats a carefully selected snapshot.

    Has the IA32 c++ ABI been finalised (and implimented), or will there still be one more round of c++ program breakage?

  24. Re:Source Code =) on Microsoft's New Language · · Score: 1

    I thought that PLEASE DON'T CRASH was an intercal
    instruction.

  25. Re:Spread the message, brothers on Copyrant · · Score: 2
    You don't seem to understand the impact of the UCITA. It is a law proposal that will exactly do that: put the magic in cellophane.

    I think you've misunderstood the original comment. The point (I think) was that there is no reason the licence has to be hidden behind cellophane to be valid. If BigCorp tells me that they disclaim all warrenty only after I bought it, and UCITA makes that valid, then surely GPLSoftwareCompany can tell people that beforehand? If UCITA makes one valid, why does it not make the other valid?

    "There's no magic in hiding the license behind cellophane, rather than stating it up front" what I think what was meant.

    Or does UCITA make one valid, butnot the other? When was the last time someone went to a software company, and said "your software crashed", and got a refund, anyway? People had enough trouble trying to give back MS software - something which the licence specifically states that you can do.