network profile
| bio | website | |
|---|---|---|
| location | ||
| age | 49 | |
| visits | member for | 1 year, 9 months |
| seen | Jan 18 at 12:53 | |
| stats | profile views | 15 |
I'm a professional programmer with a mathematical disposition.
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Nov 1 |
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Name this concept: Comparing equal sized vectors vs. comparing features You might want to ask this on astronomy.stackexchange.com. I think they do something similar to align sequences of images in order to get an enhanced composite image. |
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Sep 29 |
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circle that touch quadrantal internally @J.M.: I'm assuming kim want's the inscribed circle |
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Sep 26 |
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Why is this curve convex? Are you sure they want you to use polar coordinates? You could put $\theta$ on the x axis and r on the y axis. |
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Sep 21 |
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4 items add up to and multiply to 7.11 what are the value of the items? @anon: Right you are! (duh!) |
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Sep 21 |
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4 items add up to and multiply to 7.11 what are the value of the items? @anon: if $\pi$ is too expensive, maybe I can just buy a piece? |
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Sep 21 |
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4 items add up to and multiply to 7.11 what are the value of the items? Hmmm, the prime factors of 711 are 3*3*79. There aren't many choices for the prices here, and none of them add up to 711. For example, 1*1*9*79 = 711, but the sum isn't even close. |
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Sep 21 |
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4 items add up to and multiply to 7.11 what are the value of the items? Hint: This is a Diophantine problem. Besides the sum and product, you also have that the answers (expressed in cents) are integers. |
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Sep 21 |
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Curvature of the image of a curve projected onto a surface I haven't tried yet, but will sometime in the next week (or two). I don't see why it wouldn't though. I'll post the Mathematica results here when I do. |
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Sep 20 |
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Curvature of the image of a curve projected onto a surface Thanks, I appreciate the effort you put into this. I really like the idea of creating an orthogonal basis in the tangent space. I can make this work. |
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Sep 20 |
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Curvature of the image of a curve projected onto a surface Thanks for this. I'm not clear why you say that I forgot to mention p, k, and d, (as k and d are of your own construction) and I don't know what you mean "it's a pullback". I'm not I can I turn this into a finished solution for d given that S is unknown in advance (we are only guaranteed that we can inquire it's derivatives). |
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Sep 20 |
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Curvature of the image of a curve projected onto a surface It's not clear to me that the construction as you describe it gives the correct curve. Can you justify the idea that there is a locally aligned parametrization that has the second derivative projection properties? Unfortunately I have to award the bounty soon, so please answer quickly. I'll give it some further thought myself. |
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Sep 18 |
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Curvature of the image of a curve projected onto a surface @alex: the surface will generally be a NURBS surface, so there is no hope of an implicit form. Thanks for the suggestion. |
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Aug 31 |
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“Mathematical Induction” ODEs do it for me every time! |
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Aug 25 |
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Curvature of the image of a curve projected onto a surface @anon: Thanks for this. I intend to see if I can get it to work in Mathematica, but I haven't gotten to it yet. |
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Aug 18 |
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Curvature of the image of a curve projected onto a surface I modified the question to avoid references to derivatives in $C_S$. |
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Aug 18 |
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Curvature of the image of a curve projected onto a surface @Jesse: Hmmm, that didn't come out very nice, did it. I guess you can't use html in comments? How did you get your subscripts? |
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Aug 18 |
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Curvature of the image of a curve projected onto a surface @Jesse: Actually I was a bit sloppy on my wording. <em>C<sub>S</sub></em>'(<em>t<sub>0</sub></em>) is proportional to <em>C<sub>S</sub></em>'(<em>t<sub>0</sub></em>), which is all I need in my case. This problem comes from my desire to walk along the surface tracing out the projection from an initial point. I intend to do this by estimating a step with derivative information, and then correcting by iteration. The approach of walking along the curve projecting points is flawed because the projection is one-to-many. |
