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can anyone tell me the algorithm for the pseudo random number generator? and how it works, i tried searching the net but to no avail..
thanks in advance,
nico
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niconicx wrote: i tried searching the net but to no avail..
Or this[^] one. 
If you don't have the data, you're just another a**hole with an opinion.
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See also here [^].
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Hey, I don't think that six you rolled is completly random. Since there are more pips on that face than the opposing face (one), it likely be up more often than not.
"Love people and use things, not love things and use people." - Unknown
"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch
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Well I'm working on the anti-gravity vacuum glass box... 
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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DavidCrow wrote: there are more pips on that face than the opposing face (one), it likely be up more often than not.
Not really; they're only one-sixth as deep as the one on the opposite side.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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I know, but the mass distribution is different. 
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Roger Wright wrote: Not really;
How so?
Roger Wright wrote: ...they're only one-sixth as deep...
All pips are drilled to the same depth on a die.
"Love people and use things, not love things and use people." - Unknown
"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch
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Okay, so I was guessing...
But seriously, it's only one part of the equation. On the pair of sides showing 6 and 1 pip, one can consider that a shift in the center of mass occurs equal to some distance proportional to the ratio of the mass of one pip to the entire die in the direction of the face with 1 pip. Call that distance (6-1)l = 5l, and its direction i .On an adjacent face, the 5 counters the 3 for a distance of (5-3)l = 2l in the direction j. Normal to the plane formed thus is the pair 4 and 3, at a distance l in the k direction. The total distance by which the centroid shifts is then sqrt(25+4+1)*l = 5.477*l. Its direction is left as an exercise for the student, but it is decidedly not toward the face showing a 1. Remember, too, that we can't just rely on the measure of missing plastic in the pips, but must add back the mass of the paint used to mark each, and that might have a specific gravity much higher or lower than the base material.
For practical purposes, the amount shift in the center of mass is negligible compared to the random variations in surface texture of the felt on the table, and the influence of random air currents from breathing, talking, air conditioning, passers by, and the occasinal fart. 
The outcome is close enough to random for any engineering use, though a mathematician might argue the point.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Roger Wright wrote: For practical purposes, the amount shift in the center of mass is negligible compared to the random variations in surface texture of the felt on the table, and the influence of random air currents from breathing, talking, air conditioning, passers by, and the occasinal fart.
Hey, you're definitely cheating: my (pseudo ) random device rolls in a vacuum box!
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Well then, I guess the only way to resolve the matter is for you to build your machine, then run it through 6^(6^6) iterations and see if the Universe ends.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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CPallini wrote: See also here [^].
im sorry for being somewhat dumb.. but can you explain the picture? thanks..
regards
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Well it is a (pseudo: see David Crow's post...) random number generator device.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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LOL. It is a pratical random generator. I used to write numbers on my square eraser and toss them to decide my answer for Multiple Choice Questions during tests that I didnt study.
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I obtained better results even for tests I did study.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
modified on Tuesday, September 16, 2008 11:42 AM
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I'm using a scanner to create my tokens and a parser to create the tokens into a meaningful AST.
After a good start on my project, I noticed that if i made my scanner create generalized tokens my parser logic needed more work but if i create more specific tokens my parser logic was greatly reduced.
anyone have a rule of thumb(s) when i should put the responsibility on the scanner or when it should be placed on the parser?
-lm
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I can only speak from a compiler-creation point of view but scanners (lexical analyzers) are generally pretty simple... much simpler than the parser-portion of the process. My "rule of thumb" is that the scanner/lexical analyzer (lexer) scans the input file, breaks it into tokens, and identifies the type of token. Done. It knows nothing about syntax. That is where the parser takes over.
Maybe this is just a matter of semantics, but if your parser is taking up too much responsibility, rather than leaning on the scanner to provide more information, maybe you can break the parser down into more parts and divide the responsibility that way (again, speaking from a compiler point of view):
1. Scanner (Lexical Analysis) - Break your source code down into small tokens.
2. Parsing (Syntax Analysis) - Check for correct syntax and build your abstract syntax tree (AST). The parser checks strictly for syntactic correctness and stops there.
3. Tree Analysis (don't know the "real" name for this subtask) - Analyze and add information to your your syntax tree for semantic correctness (i.e. variables declared, initialize to default values, etc).
4. Optimization / Generation - What this is depends greatly on what your specific task is.
Enjoy,
Robert C. Cartaino
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so how small should the scanner make the tokens?
Example:
i can create greedy tokens like this:
DCode:= 'D'[0-9][0-9][0-9]
GCode:= 'G'[0-9][0-9]
MCode:= 'M'0[0-2]
or specific tokens like this:
GCodeG36 := 'G36'
GCodeG37 := 'G37'
after working some on my parser this morning i like the more specific expression better. Simplifies my parsing.
my parser can just check:
"is a type"
matches &= scanner.Next() is DCodeD02Token
vs
"is a type with a value of this"
matches &= scanner.Next() is DCodeToken && ((DCodeToken)scanner.Current).DCode == 2;
I would like to see an example of tree analysis. might help me with my current problem of:
http://www.codeplex.com/irony/Thread/View.aspx?ThreadId=35310[^]
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Umm, I'd like to start by admitting that I have a learning disorder in Mathematics. I was wondering however if anyone knew of a way to make or know of a application that would allow someone to change an equation out of a physics textbook or on a chalk board to a linear form used in a programming language (everything on one line). I realize this is a crazy question to ask but I'm trying to learn a language called Dark Basic and I keep looking in phyics books but it has everything in a longer form that's not compatible. Please anyones reply would be appreciated.
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It's not a crazy question, but it is indecipherable. Could you provide an example? Are you referring to condensing multiple equations into a single line? Many languages allow you to place multiple statements on a single line, separated by a special character - the ';' is one that is used.
As for learning disabilities, I wouldn't be too sure. I taught many students who were told they would never learn math by previous instructors. All of them learned math in my class. More often it is a teaching disability that prevents students from learning it.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Please elaborate: for instance one usually uses linear approximations to the solutions of physical equations...
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
[My articles]
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Dale Keller wrote: I realize this is a crazy question to ask
Actually, it is indecipherable as Roger has said.
It might be helpful to know of any ideas you have thought up.
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
"Not only do you continue to babble nonsense, you can't even correctly remember the nonsense you babbled just minutes ago." - Rob Graham
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I'm having trouble understanding what you need too. Physics equations are usually on one line, while a programming-language implementation often uses several assignment statements.
The rules for transforming equations are pretty straightforward, and with some practice can be mechanically applied.
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