User rlbond - MathOverflow most recent 30 from http://mathoverflow.net 2013-05-26T03:10:42Z http://mathoverflow.net/feeds/user/2317 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/9754/magic-trick-based-on-deep-mathematics/9766#9766 Answer by rlbond for Magic trick based on deep mathematics rlbond 2009-12-26T01:55:44Z 2009-12-26T01:55:44Z <p>You can use hamming codes to guess a number with lying allowed. For example, <a href="http://www.ms.uky.edu/~jrge/Papers/Hamming.pdf" rel="nofollow">here</a> is a way to guess a number 0-15 with 7 yes-or-no questions, and the person being questioned is allowed to lie once. (The full cards are <a href="http://www.ms.uky.edu/~jrge/Papers/Seven%5Fcards.pdf" rel="nofollow">here</a>).</p> http://mathoverflow.net/questions/9311/cubic-spline-of-a-two-variable-function Cubic spline of a two-variable function rlbond 2009-12-18T20:51:36Z 2009-12-26T01:25:28Z <p>So, I am aware of how to (both iteratively and using a linear equation) compute the cubic spline of a one-variable function with \$m\$ control points. However, I am not sure how to do any type of spline on a two-variable function with \$mn\$ control points in a square grid. Is this even possible? Is there a simple algorithm? I've tried to see if the process is separable, but so far I can't seem to prove it one way or the other.</p> http://mathoverflow.net/questions/9311/cubic-spline-of-a-two-variable-function/9763#9763 Comment by rlbond rlbond 2009-12-26T01:49:34Z 2009-12-26T01:49:34Z Thanks, will see if I can get my hands on it.