HELPPPPPPPPP!!!!!, 4th Degree polynomial equation |
HELPPPPPPPPP!!!!!, 4th Degree polynomial equation |
Chitralekha |
Aug 28 2004, 07:24 AM
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#1
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Dedicated Member Group: Members Posts: 4431 Joined: 22-October 03 Member No.: 13 |
How do I find a 4th degree polynomial passing through 1000 points (x,y) format??
Any methods to use? Vandermonde matrix doesn't work Mathematics experts please help!!!! |
myawan |
Aug 28 2004, 07:42 AM
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#2
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Dedicated Member Group: Members Posts: 4917 Joined: 28-October 03 From: Lahore Member No.: 57 |
needs elaboration.
============================== For me, listening to Mohammad Rafi is an addiction! |
Chitralekha |
Aug 28 2004, 08:08 AM
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#3
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Dedicated Member Group: Members Posts: 4431 Joined: 22-October 03 Member No.: 13 |
See in this example, the red line passes through the points, I want to make a 4th degree polynomial like that.
function of a form y = ax^4 + bx^3 + cx^2 + dx + e Attached image(s) |
Chitralekha |
Aug 28 2004, 08:10 AM
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#4
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Dedicated Member Group: Members Posts: 4431 Joined: 22-October 03 Member No.: 13 |
Something very much like this.
How do I do that? Attached image(s) |
myawan |
Aug 28 2004, 08:18 AM
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#5
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Dedicated Member Group: Members Posts: 4917 Joined: 28-October 03 From: Lahore Member No.: 57 |
still unable to understand, first image is of a first degree polynomial i.e. equation of a straight line but the second image is not of a fourth degree. What do you mean by passing through 1000 points, ofcourse a line passes through unlimited number of points.
============================== For me, listening to Mohammad Rafi is an addiction! |
Chitralekha |
Aug 28 2004, 08:31 AM
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#6
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Dedicated Member Group: Members Posts: 4431 Joined: 22-October 03 Member No.: 13 |
The points are scattered in 2D plane. You there is only one possible fourth degree polynomial that would pass through the scatter.
Am I not explaining it right? |
myawan |
Aug 28 2004, 08:37 AM
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#7
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Dedicated Member Group: Members Posts: 4917 Joined: 28-October 03 From: Lahore Member No.: 57 |
You mean that you have been given the points and you have to find the equation of that curve, isn't it?
============================== For me, listening to Mohammad Rafi is an addiction! |
Chitralekha |
Aug 28 2004, 08:52 AM
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#8
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Dedicated Member Group: Members Posts: 4431 Joined: 22-October 03 Member No.: 13 |
Precisely! |
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anurag |
Aug 28 2004, 03:42 PM
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#9
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Dedicated Member Group: Members Posts: 1618 Joined: 18-June 04 From: Xanadu, K-Pax Planet Member No.: 550 |
use a 4th degree B-Spline function to interpolate -- will also ensure at least C^2 continuity at all intermediate points. There is recursice deboor-cox formula that you can use to evaluate interpolating functions. Socrates said, "The unexamined life is not worth living". I fear if I examined it, then according to Heisenberg uncertainty principle it would somehow change. After all, we are just particles.
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Chitralekha |
Sep 5 2004, 02:48 AM
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#10
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Dedicated Member Group: Members Posts: 4431 Joined: 22-October 03 Member No.: 13 |
QUOTE(anurag @ Aug 28 2004, 03:12 AM) QUOTE(Chitralekha @ Aug 28 2004, 07:24 AM) How do I find a 4th degree polynomial passing through 1000 points (x,y) format?? Any methods to use? Vandermonde matrix doesn't work Mathematics experts please help!!!! use a 4th degree B-Spline function to interpolate -- will also ensure at least C^2 continuity at all intermediate points. There is recursice deboor-cox formula that you can use to evaluate interpolating functions. Anurag, the data is equidistant. No interpolation needed. I couldnt understand the B-spilne functions. I need to find an example of it to understand and no sites have it. Thanks for your efforts. |
unni |
Sep 5 2004, 04:20 AM
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#11
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Dedicated Member Group: Away Posts: 8769 Joined: 20-March 04 From: Vaanar Nivas, Tribandar Marg, Bandarabad, MONKEYSTAN. Member No.: 356 |
C'lekha:
[/quote] Anurag, the data is equidistant. No interpolation needed. I couldnt understand the B-spilne functions. I need to find an example of it to understand and no sites have it. Thanks for your efforts. [/quote] Neither does the "Beastiality" site have thine picture. Hurry up, no? If you stop trying to make sense of it all, you'll be less confused. Reality is an illusion.
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anurag |
Sep 5 2004, 07:15 AM
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#12
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Dedicated Member Group: Members Posts: 1618 Joined: 18-June 04 From: Xanadu, K-Pax Planet Member No.: 550 |
QUOTE(Chitralekha @ Sep 4 2004, 05:18 PM) Anurag, the data is equidistant. No interpolation needed. I couldnt understand the B-spilne functions. I need to find an example of it to understand and no sites have it. Chitra, check your PM. anurag Socrates said, "The unexamined life is not worth living". I fear if I examined it, then according to Heisenberg uncertainty principle it would somehow change. After all, we are just particles.
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Wehshee |
Sep 14 2004, 11:59 PM
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#13
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Unregistered |
good shot uni !
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vivekpm |
Sep 15 2004, 09:07 PM
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#14
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Dedicated Member Group: Members Posts: 1404 Joined: 22-November 03 Member No.: 120 |
Do share the solution if you have got it by now... If not can you give any 5 points out of 1000 available points? I am assuming you have set of points with you...
Cheers, V i V e K ...
-------------------------------------------- Education is a progressive discovery of our own ignorance. -- Will Durant |
Chitralekha |
Sep 17 2004, 08:28 AM
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#15
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Dedicated Member Group: Members Posts: 4431 Joined: 22-October 03 Member No.: 13 |
QUOTE(vivekpm @ Sep 15 2004, 08:37 AM) Do share the solution if you have got it by now... If not can you give any 5 points out of 1000 available points? I am assuming you have set of points with you... Cheers, No solution found yet. I dont know how to find the first derivative (for the B-spline). Attaching a file with those 1000 points. Let me know if you can find a solution. Thanks. |
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