

Hi Alan!
Would it be possible to enumerate "GIF, JPG" etc... and use those in the neural net? Or is it only good if it's binary?
The goal of this program is to adapt the interface to each user. The user logs into their profile, and the interface would then be different based on what the user usually does. So for someone who tends to select 'car' after 'wallpapers', the interface would automatically streamline to have those two near each other. There would be a huge number of permutations and so I am wary of simply having a huge matrix that contains all possible combinations and thei relative probabilities.
Thanks for the help.





If you have more than two items in an enumeration, you're implying an ordering that doesn't exist to the neural net. You could have separate input neurons for GIF, JPG, etc. that would each be 0 or 1.
Adapting the user interface to streamline a user's work flow is a good idea. It might help to look at logs of actual users' patterns to see what you'd get the most benefit from optimizing.





I think that's the best way to go about it. I should have each attribute as seperate input neurons and see if they 'fire' the neuron. If I was to go about using neural networks, am I correct in thinking that the best way to do this is to use the backpropagation method? Or is there one better suited for this scenario?
Also, could I achieve the same effect using (Hidden?) Markov models?
Thanks again for the help. Much appreciated!





The backpropagation method is the standard algorithm for training a neural net. There are many variants but there's no consensus yet on which is better. They generally give similar results.
With neural nets, you can take the user's last n selections into account by simply adding more input neurons. With a Markov process, only the last state is considered.





What's the algorithm for finding the shortest path for connecting points on a plane, provided that:
1 You can use unlimited branches
2 You can move vertically and horizontally only, no diagonal moving
3 The first point, which is the starting point, is predefined
Please provide me with algorithm ,flowchart, vb, c++, etc.... code for this problem
Thank you





I'm talking about infinite points
or maybe we can say, 10 points
please check the attached picture
Legend:
Blue: First point
Red: Destination points
Black: The shortest path
http://img413.imageshack.us/my.php?image=sample1ty5.jpg





The people who post here are not paid to answer questions or help people. They will help you out if they can and they feel like it. They will do so by giving answers to specific questions, refering you to sources of information, ect... but they are not going to write the code for you unless it is very very short (say 2 lines long). We're here to help each other out, not to do other people's work for them.
I would recommend you either post this at a place like rent a coder where you will have to pay someone or else refrase this as a question not a request to do it for you.





Thank you for your reply
But I didn't request them to write code for me
Sorry for making the question look like that
I just wanted any available information about this topic
After some investigation, I found this library:
http://www.diku.dk/geosteiner/[^]
which I think will solve my problem using Steiner Trees....





Hi, can somebody tell me how to create a plane passing through 3 points and how to project a point onto this plane.I have to develop a c/c++ code to do that.Can somebody suggest me a way or a good algorithm to do it.Plse do help me out.Thnk You.





one way:
all variables are vectors, the three points are defined by their position vectors r1, r2, r3, and the given point is simply r.
v1 = r1  r3
v2 = r2  r3
unit normal on plane
n = (v1 x v2) / v1 x v2
then the position vector of the projection point is
r  ((r  r1).n)n
[edit]
forgot to add that the equation of the plane is
(r  r1).n = 0
where r is the position vector to a point on the plane
[/edit]
Peter
"Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."
modified on Friday, August 29, 2008 5:09 AM





Thnx for the reply.Ill chk it out.





Hi.I'm researching on an algorithm about the counting car on traffic. We're using to camera to catch and count the cars but I have some problems about this.
The problem is we know the coordinates of cars on the way. For example 4 cars with their coordinates in 1st frame. At 2nd frame lets say 1 car goes out from the camera view point and new car comes in. At 3rd frame no car goes out and 2 car come in to the view point.
So the video will like this;
First Frame = 4 Car 4 new
Second Frame = 4 Car 1 new
Third Frame = 6 Car 2 new

Total Passed Cars =7 CARS
With our calculation we know that 7 car passed from way. But the problem is camera cant recognize which car is from old frame.
I want a suggestion from you. Any ideas about to solve this? Please help me...





Sounds like you either need to upgrade your frame rate so you can track the cars incrementally, that is, their motion between frames is less than a car length so you can infer the same car because it was in the previous frame and couldn't have moved more than a certain distance between frames. If you can find partial cars, you can track them entering and exiting the frame as well. Otherwise, it seems you need a way to uniquely identify the cars in the frame. Color (assuming you're capturing color) could be used but that's, obviously, not robust since cars can be the same color and it's prone to lighting problems. Even if you can identify features of the cars, it's not entirely robust since tens of thousands of identical (at least from an exterior perspective) roll off the assembly lines each year.
If you don't have the data, you're just another a**hole with an opinion.





BTW, you didn't say how you were detecting cars and the camera setup or what kind of literature search you'd done. There are thousands of items on the web about the topic.
If you don't have the data, you're just another a**hole with an opinion.





I have am trying to find the difference between factor and coefficient. Searching shows they both are used a lot but I have been unable to find a good comparison of the two (various online dictionary definitions aren't a lot of help). What I have been able to find implies they are the same  the coefficient of friction (ratio of tangential force to the perpendicular normal force) and drag factor (total acceleration force divided by weight). Each results in a multiplicative number. What am I missing? What is the difference?





AFAIK, a coefficient is used for a multiplicative constant while factor has a more general meaning (i.e. multiplicative operand).
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]





Hi. I want some stuff regarding Bin Packing Algorithm. plz help me.
modified on Thursday, July 31, 2008 1:12 AM





2489128 wrote: I want to sum stuff
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]






What help you need? Idea how to do it or just code so you don't have to and not learn a thing?
"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





Actually i want detailed stuff i.e. theory, Calculating order etc. I've to implement it in my project.





And none of the 6360 hits for bin packing algorithm that come up on Google helped you any?
If you don't have the data, you're just another a**hole with an opinion.





Actually I've found some good stuff but all are paid.
1
2
3
I want some free stuff for study purpose.





Does this [^] help?
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]





2489128 wrote: I want some free stuff for study purpose.
Then you needed to be more specific in your question. Your question essentially came across as I have a homework assignment that involves the bin packing algorithm and you're too lazy to even look it up. You didn't tell us what you knew or didn't know. There was no specific question.
If you don't have the data, you're just another a**hole with an opinion.





You may also try to implement it using Simulated Annealing [^].
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]





Tim Craig wrote: none of the 6360 hits for bin packing algorithm that come up on Google helped you any?
Certainly there has to be something useful in those 6360 results
"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





Paul Conrad wrote: Certainly there has to be something useful in those 6360 results
I learned more about it than I wanted to from the first one, the Wikipedia article.
If you don't have the data, you're just another a**hole with an opinion.





Which part? Where it says that it is a combinatorial NPhard problem?
OT: Now only if google could help me figure out why Access won't work with a .dll I registered grrrrrrrrr
"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





Paul Conrad wrote: Where it says that it is a combinatorial NPhard problem?
Pretty much. I actually worked on a project that did order picking of product from a carousel system to bins about 20 or so years ago. Fortunately, I got to work on more interesting parts of it and then went off to better problems.
Paul Conrad wrote: why Access won't work
Microsoft?
If you don't have the data, you're just another a**hole with an opinion.





Tim Craig wrote: Microsoft? [Poke tongue]
Uh huh. The bastard works locally, but once I try to run the database over the network, it freaks out over the .dll, registered and everything. Nothing like doing a demo to the client, selling them on it, and now it craps.
They heard plenty of ranting and raving about Access today before this project
"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





The way the searching goes these days, maybe the cure for cancer... Or one of those fake websites that plauge google and pops up with people offering to pack your bins. Who knows? Google doesn't .
He who asks a question is a fool for five minutes. He who does not ask a question remains a fool forever. [Chineese Proverb]
Jonathan C Dickinson (C# Software Engineer)





I have solved FDIST in C#. now I have to find FINV
Which Returns the inverse of the F probability distribution. If p = FDIST(x,...), then FINV(p,...) = x.
Any idea about this. how to find inverse of the F probability distribution
Syntax
FINV(probability,degrees_freedom1,degrees_freedom2)
Probability is a probability associated with the F cumulative distribution.
Degrees_freedom1 is the numerator degrees of freedom.
Degrees_freedom2 is the denominator degrees of freedom.
thanks in advance





Follow the same steps you did before with the FDIST. Research for the algorithm how to do it, find code implementing the algorithm, and code yours.
"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





I Didn't Find any algorithm related to finv anywhere.
except that
FINV depends on precision of FDIST. FINV uses an iterative search technique. If the search has not converged after 100 iterations, the function returns the #N/A error value.
now i dont know how to do these iterations using FDIST?






Does it work as well as the one in Excel?
"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






Very nice. Have you considered writing an article about what you have been doing lately with all of these statistics problem you have been encountering?
"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





Hi,
I've a problem with the proper conversion of double to it's string representation.
For example.
If I've in the code some double value:
double a = 69000.015;
the debugger in debug window will show 69000.014999999999 but not 69000.015
Generally I need the precision and number of significant digits for the conversion.
For sprintf(...) I have to specify the precision and specifier.
How can I get the correct precision of the double value?
Is there any solution/clases for this type of conversion?
Thanks.





Hi,
there is simply no solution to your problem. Floating point numbers, by their very nature, cannot always represent the intended value.
The simplest example is the outcome of 1.0/3.0
humans write it down as 0.333333..., computers perform the division in binary and get a reasonably
accurate quotient (say off by no more than 1 of the lowest bit position), which is after all
an approximation.
The binary approximation of 1/3 is something like 1/4 + 1/16 + 1/64 + 1/256 + ...
and it has to stop somewhere since there are only so many bits reserved for the mantissa.
Similar things will happen to almost all real numbers; in order to avoid it, the number must
happen to be an integer value possibly divided by a power of two.
Hence 1.0/4.0, 7.0/4.0, 23.0/256.0 etc can be represented exactly,
whereas numbers with a prime factor (other than 2) in the denominator will not be exact,
nor will irrational numbers (such as pi, or the square root of 2).
If you know how many decimals (i.e. digits behind the decimal point) are required to get an exact
representation, then order that number of decimals or fewer. Rounding will occur, and everything
will look very natural.
If you don't know the number of decimals required and care very much about the correctness of them,
say you start your own financial program or business, then you'd better have a look at the decimal type. It offers a smaller range of numbers, but in some sense a better accuracy.





Thanks Luc for the answer,
but unfortunally I'm not a Fortran developer, I do Visual C++ which do not have a decimal type.
But the 69000.015 is non preiodical double(not like 1/3=0.333333...) and internal CPU's data register representation will be a particular correspondent binary. I'm not a pro in math, but for me seems like it needs some analysis of the binary representation to get a precision.





This page [^]may show the internal representation of a decimal number as double.
It comes out, that 69000.015 is represented with 40F0D8803D70A3D ,
i.e. 1.0528566741943360 as significand and 16 as exponent.
If you put the above number in windows calculator then you'll get:
1.0528566741943360 * 2^16 = 1,0528566741943360 * 65536 = 69000.0150000000040960
probably not exactly what is expected by you.
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]





No real simple solution due to the way floating point numbers are represented in binary form. You'll always have some odd round off to deal with.
You could always try using the Decimal type...
"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





You won't always have round off to deal with. Binary fractions like 1/2, 1/4, 3/4, 1/8, etc. can be exactly represented as a double. But you're right that most numbers can't (assuming that the word "most" can be used of an infinite set).
The reason we put up with the inexactness is that exactness doesn't exist in the physical world. If a piece of wood is "2.4 meters long", it's really "2.4 meters give or take a millimeter" (which would be written as "2.400" to emphasize this). So, then, what difference does it make if your computer represents the length as 2.399999999999999911182158029987476766109466552734375 m, off by a mere 8.88e17 m, when the physical accuracy is nowhere near that good?
The one exception is money. If something costs $3.99, it costs exactly $3.99, not $3.9900000000000002. If the sales tax is 8.25%, it's exactly 8.25%, not 8.2500000000000004%. And, because we use decimal currency, Decimal classes are often used for monetary amounts.
You could use it as a generalpurpose number class, but:
(1) It's not a panacea for rounding error. You still have to deal with 1/3 + 2/3 != 1.
(2) Due to the lack of hardware support, it's much slower than binary floats.
Therefore, I wouldn't just blindly recommend "use Decimal ". If your only complaint with float or double is the string representation, then just use a smaller precision in sprintf or string.Format or the equivalent in your favorite language. (15 digits in the 'g' format will usually get the job done.)





Read this[^]
Peter
"Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."





Hi,
I have a string with value "111733394601234567094987654321" . Now i want to divide this with 636. I convert it to double , then im getting 1.1173339460123456E+29 . but these both values are differnt finally im
getting wrong output. can anyone help me.....
Thanks
Prathap





If you do this for the cryptograpy purposes use any kind of Crypto API, it works with very long integers.





I know there's lots  but does anyone have favorites, for ease of use and scope?





You might get better results asking for an algorithm rather than code.
If you don't have the data, you're just another a**hole with an opinion.



