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patdistheman

B is generated from the formula below. B = roundeddown((H + 1) / 10)) The following table shows that when H = 150 that B = 15. Without knowing the formula in advance how do you use just the information in the table to determine the formula? 150 15 165 16 181 18 199 20 219 22 241 24 265 26 291 29 320 32 352 35 387 38 425 42 467 46 513 51 564 56 620 62 682 68 750 75 825 82 907 90

  • one year ago
  • one year ago

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  1. wio
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    What do we get to assume? That the function uses rounding and is linear?

    • one year ago
  2. patdistheman
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    Well what would be ideal is to not be able to assume anything look at the table and generate the formula listed above which predicts future outcomes.

    • one year ago
  3. campbell_st
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    this is called a floor function that rounds down to an integer value. The graph is a step function or piece wise function. Someone asked the other day about ceiling functions that I'd not heard of... I looked it up and its and found out about floor and ceiling functions. the notation is something like |dw:1356938017922:dw| so if you put in a value of H say 155 you get (155 +1)/10 = 15 when rounded down. thats about all I know on these things

    • one year ago
  4. patdistheman
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    I am trying to determine how to go from the table of numbers to the formula but any information that you could provide is appreciated. Thank You.

    • one year ago
  5. campbell_st
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    look up floor function it may help

    • one year ago
  6. patdistheman
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    The floor function rounds the number down. I do not see the connection to determining the formula from the table of data.

    • one year ago
  7. sauravshakya
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    B= roundeddown((H+2)/10) will also generate the same table

    • one year ago
  8. sauravshakya
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    So, from the given table u cannot find a uniqe formula

    • one year ago
  9. patdistheman
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    It stands to reason that if the formula generates the table that if you have a sufficient amount of the table results there must be way of determining the formula. However based on the fact that no on here has been able to answer this question in quite some time it may not be a universal math formula that can used to get the solution.

    • one year ago
  10. LogicalApple
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    I can only think of recursive approaches to this, but no useful formula. This is an interesting problem.

    • one year ago
  11. patdistheman
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    It appears it would have to be recursive due to the way that b relies on the value of h...

    • one year ago
  12. LogicalApple
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    I wrote a java application for it the other day but the recursion was too much to calculate. I couldn't get to the 100th cycle.

    • one year ago
  13. patdistheman
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    Interesting...

    • one year ago
  14. LogicalApple
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    If anyone can generate a straightforward formula for this I would love to see it!

    • one year ago
  15. patdistheman
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    I would be willing to put some prize money... lol

    • one year ago
  16. wio
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    The thing is, there are multiple solutions to the problem. In fact you could make a continuous polynomial to perfectly match the data.

    • one year ago
  17. wio
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    That is why any program that makes up a best fit curve will ask you to at least narrow it down to a distribution (linear, quadratic, power, exponential, etc).

    • one year ago
  18. wio
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    @LogicalApple Did you use any memoization/caching, or did it have to do redundant recursive calls?

    • one year ago
  19. LogicalApple
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    If you could determine THAT equation based on the output, then you must be privy to some mathematical enigma that eludes the rest of it. @wio said there are so many solutions to this...but the original equation here uses a floor function... that makes determining an equation even harder.

    • one year ago
  20. LogicalApple
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    No caching just plain recursion. I once tried to program an Ackermann function ...

    • one year ago
  21. patdistheman
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    If you type in the pattern into wolfram alpha with fit in front of it... For example... fit (0,0) (1,5) (2,10) (3,15) it will generate the formula for you but I do not think this formula matches any of those criteria. (linear, quadratic, power or exponential)

    • one year ago
  22. wio
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    @patdistheman Send me a link.

    • one year ago
  23. patdistheman
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    Of what wolfram alpha?

    • one year ago
  24. patdistheman
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    http://www.wolframalpha.com/input/?i=fit+%280%2C0%29+%281%2C5%29+%282%2C10%29+%283%2C15%29

    • one year ago
  25. wio
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    yeah, wolfram alpha coming up with a formula that has a floor function.

    • one year ago
  26. patdistheman
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    I did not reference wolframalpha and a floor function. Just the results of punching fit (0,0) (1,5) (2,10) (3,15) into wolframalpha.

    • one year ago
  27. wio
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    ah, I see.

    • one year ago
  28. patdistheman
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    Although yuo can use the floor function on wolframalpha... http://www.wolframalpha.com/input/?i=floor+9.11

    • one year ago
  29. wio
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    Right, what wolfram does is just tries out multiple distributions and gives you the most reasonable ones.

    • one year ago
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