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  1. K

    Anyone know prolog?

    Does anyone here know Prolog? I'm using the SWI-Prolog interpreter. Given this list: [[1, 2], [2, 3], [3, 4]] how do you make it say Yes if 2 (of the first list) = 2 (of second list) and 3 (of second list) = 3 (of third list)? I'm having trouble visualizing this fact as the elements in the...
  2. K

    Java How do display/generate webpage content with info from an array in a .java file?

    Does anyone know how I would go about displaying/generating webpage content with info from an array in a .java file? Suppose you click on cars.com, once you do, the webpage will display the contents (say car names) of an array from a .java file. How do I do this? Thanks.
  3. K

    Context-free grammar: derivations and ambiguity

    Can I just draw the two parse trees of the two different derivations of the same string and come to the conclusion that the language is ambigious?
  4. K

    Context-free grammar: derivations and ambiguity

    I have a question regarding about CFGs, derivations, and ambiguity. Say you are given some CFG that produces A, B, or C You are able to come up with two different derivations for A To say the CFG that produces A, B, or C is ambiguous, you must find two different parse trees for some...
  5. K

    Simplifying regular expression?

    Hmm, so it cannot be simplified to something really short ie. (a|b|c)*b (which is wrong) as it seems. Thanks.
  6. K

    Simplifying regular expression?

    Does anyone know if this regular expression can be simplified? (a*bc*bc*|c*)*b I tried (a|b|c)*b, but it's not correct.
  7. K

    XQuery XML help

    I have to write an XQuery that for example, "returns a list of books for a given author". The "given author" in this case can be anything. Therefore, I was wondering what do I need to add to give the query someting, which in return, it will process it. For example, for $x in...
  8. K

    Minimum closure of F (functional dependencies) help

    Homework Statement F = {S -> NOPQZVWX, NX -> UV, NXT -> RY, YQ -> NXR, QZ -> S, PQ -> S} Find the minimum closure of F. Homework Equations none The Attempt at a Solution So far I have made RHS of each FD into a single attribute and then I eliminated redundant attributes from...
  9. K

    Help Joining Two Tables in SQL?

    That worked. Thanks a lot for your help!
  10. K

    Help Joining Two Tables in SQL?

    Thanks, that worked, but what do you need to add if there are duplicate entires in Table 1? ie. Table 1 A B 1 4 1 4 2 5 3 6 Using the latest query you wrote, I get the resulting table: Table 1 A B C 1 4 6 2 5 3 6 One of the same 1 4 entry is removed. I tried taking out the...
  11. K

    Help Joining Two Tables in SQL?

    Thanks for the reply. I just gave that a try and it did the following: Result A B C 1 4 2 5 3 6 1 4 6 I'm using PSQL PostgresSQL to do this stuff. Should it be the same with your tsql code? Because I get the table above when doing your example.
  12. K

    Help Joining Two Tables in SQL?

    I'm having trouble getting the following work. Can anyone help me? I have two tables that look like the following: Table 1 Table 2 A B A B C 1 4 1 4 6 2 5 3 6 How do I join both of them such...
  13. K

    Big-O and big-omega question

    Hi, I am a bit confused here. Just say you're given code and it says to show the best-case analysis and the worst-case analysis. When you show the best-case, what should the answer be in? In big-O or big-omega? Similarly, if you show the worst-case, what should the answer be in? big-O or...
  14. K

    Dijkstra's algorithm proof?

    Does anyone here know how to prove this? I'm stuck on how to even get this started. Let G be a connected, weighted and undirected graph where all edges have a weight of 1. Prove that if Dijkstra's algorithm is run on this graph, G, then the tree returned is a breadth-first tree.
  15. K

    Finding a constant for a partial differential equation

    Can anyone help me with this question? I tried taking the derivative of u with respect to x and then summed the third derivative, but I'm getting nowhere. Any help would be great, thanks. Let u(x1, x2, … , xn) = http://img480.imageshack.us/img480/1694/image0027hm.gif [Broken],[/URL] where a...
  16. K

    Computer science proving big-O definition

    Alright, I will give that a try, thanks.
  17. K

    Computer science proving big-O definition

    Whoops, I meant that I solved for (f - g)' because we want to know when the function is >= 0 and not less than 0. Am I doing the right thing?
  18. K

    Computer science proving big-O definition

    Hmm, I couldn't really think of an algebraic way of capturing that, but what I did was find the derivative of f and g. Then I solved for g'(n) - f'(n) = 0 and got n = 133.3 and -0.12. However, I do not know how to better show that f is less than c * g(n) for n >= 210. btw, I solved the |f -...
  19. K

    Computer science proving big-O definition

    I have two questions here. I must prove that f(n) = 100n^2 + 5n + 10 is in big-O of g(n) = n^3 - 100n^2 I already found a constant c and an n that satisfies the condition such that f(n) \leq c * g(n). Let c = 1 and n = 201. However, I am stuck on showing/manipulating the algebra that this is...
  20. K

    Showing a set is bounded

    Alright, I'll ditch the compact idea. Thanks a lot HallsOfIvy
  21. K

    Showing a set is bounded

    Q: Show that every bounded set in R has a least upper bound. Using either "Every monotonic and bounded sequence is convergent" or "Every bounded sequence has an accumulation point" or "Every bounded sequence has a convergent subsequence" I'm not really sure how to start this out, but would...
  22. K

    Converting 29 and 0.7 to IEEE single precision floating point

    Yes, but how would you represent that in mantissa? I'll check out that link mathmike, thanks.
  23. K

    Converting 29 and 0.7 to IEEE single precision floating point

    Hi, I just need to convert it. Not writing a program.
  24. K

    Converting 29 and 0.7 to IEEE single precision floating point

    I am having difficulty in converting 29 and 0.7 to IEEE single precision floating point. For 29, I represent 29 as a product of a power of 2 using 58/4 * 21. However, I am having trouble getting the mantissa value because 58/4 is 14.5, and I need something in the format of 1.[numbers]. Any...
  25. K

    Summation of n^2k. k = 1 to infinity

    Thanks for the confirmation.
  26. K

    Summation of n^2k. k = 1 to infinity

    Is the summation of k = 1 to infinity for n2k equal to n2 / (1 - n2)?
  27. K

    Antiderivative of the following function

    Yup, I checked it with both the first and the second integral and no dice. The antiderivative for \int \frac{4}{(4 + x^2)} \ dx is 2tan^{-1}(x/2)
  28. K

    Antiderivative of the following function

    Yup, that's what I got after the substitution and working. Sorry for replying so late. I finally had a chance to do this question just now. \int \frac{16}{(4 + x^2)^2} \ dx = \frac{32sec^{2}\Theta}{(4 + 4tan^{2}\Theta)^2} d theta where x = 2tan\Theta \ dx = 2 sec^{2}\Theta d theta...
  29. K

    Mathematica Mathematical induction question?

    Q: When a binary number is incremented by 1, there may be a carry that may carry over several bit positions i.e. 1010111 is incremented and the carry distance is 3. Given a natural number n, find the average carry distance when incrementing a binary number b in the inverval 2n <=b <= 2n+1...
  30. K

    Antiderivative of the following function

    Alright, thanks. I'll just try it again.
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