belisarius
Reputation
69,766
183/100 score
 8h comment Finding a formula for a 3D shape and colouring it @Marco There you've it 2d comment Unnecessary free space under the figure In v9 everything looks OK. Is this a v10 thing? 2d comment Issue in NDSolve and unknown error This does not provide an answer to the question. To critique or request clarification from an author, leave a comment below their post - you can always comment on your own posts, and once you have sufficient reputation you will be able to comment on any post. 2d comment SetOptions for CoordinatesToolOptions for DateListPlot? Apr15 comment How do I input an integral that needs to use Cauchy's formula? You usually specify it by sending a letter Apr15 comment Enigmatic message about MaxBend It's probably not a bug, but a bug Apr15 comment Does the two function for the same input leads to same output? So edit your question accordingly Apr15 comment Does the two function for the same input leads to same output? Of course, just set x[_] := 0 Apr14 comment Solving equations bounded by a region Have you tried starting a fresh Mma session? Apr14 comment Solving equations bounded by a region cc = {c1, c2, c3} = 1 - 3 Sin[theta]^2 Cos[phi - 2 Pi (# - 1)/3]^2 & /@ {1, 2, 3}; v = {E^(-I y), E^(-Sqrt@3/2 I x), E^(-Sqrt@3/2 I x)}; f = cc.v; llr = Re[TrigExpand@f // ExpToTrig] /. __ + Re[x_] :> x; lli = Im[TrigExpand@f // ExpToTrig] /. Im[__] + x_ :> x /. Re -> Identity; Reduce[{lli == 0 && llr == 0}, {x, y}] Apr14 comment Problem evaluating function f[y_] := Sum[D[LegendreP[n, Cos[x]], x] /. x -> y, {n, 10}] Apr14 comment Why NDSolve cannot solve such a simple set of differential equations? @Fred Vector ODEs were introduced in v9 and the syntax isn't very intuitive. As a matter of fact, you should try until it works :( Apr14 comment Iterator variable not blocked in ParametricPlot It's not a bug. It's a feature called "A New Kind of r" Apr13 comment Series Expansion true or false You're posting at the wrong site. True or False? Apr13 comment Strange Integrate messages / $RecursionLimit being ignored For Even n is very similar Apr13 comment Strange Integrate messages /$RecursionLimit being ignored For odd n -> 1/2^n Pi Tr@ Table[Binomial[n, Floor[n/2] - j ] BesselJ[0, 2 j + 1], {j, 0, Ceiling[n/2]}] Apr13 comment Fixed colors for fixed values in contourplot legend Use ColorFunction -> ColorData[{"Rainbow", {0, 3}}], ColorFunctionScaling -> False on both plots Apr13 comment Plotting six chosen rows of a matrix @johnhenry Please try the code with Wab = RandomReal[{0, 1}, {n, n}]; . If it works .... it's your matrix :) Apr13 comment Plotting six chosen rows of a matrix @johnhenry Then your W isn't a 4x4 (or larger) matrix ... Apr13 comment How to draw a tropical surface? Perhaps fns[u_, v_, w_] := {u, v, w, 0}; k = 20; RegionPlot3D[ First@Differences[Sort[fns[u, v, w]][[1 ;; 2]]] == 0, {u, -k, k}, {v, -k, k}, {w, -k, k}, PlotPoints -> 50]