line in 3d in direction of eigen vector

*To*: mathgroup at smc.vnet.net*Subject*: [mg84062] line in 3d in direction of eigen vector*From*: vicky Al Aisa <vickyisai at gmail.com>*Date*: Sat, 8 Dec 2007 05:44:56 -0500 (EST)

Hello everyone This is actually follow on. I was able to a 3d plot of an image using this (suggested by someone of u) pic=Graphics3D[ Map[{RGBColor @@ (#/255), Point[#]} &, img[[1, 1]], {2}] ] Show[pic] Now I was able to get a line in the direction of eigen vctor by doing the following ------------------------------------------------------- ColorDot=Table[0,{ImgSize},{3}]; For[i=1,i<=ImgSize,i++, ColorDot[[i]]=MeanVector+EigenVectorsColoumn[[1]]*stept[[i]] ] Graphics3D[Line[ColorDot]] --------------------------------------------------------- I was able to get a line with this , but that was black, I wanted a colored line...color depending on the coordinate( taken as RGB) So I did the following --------------------------------------------- pic=Graphics3D[ Map[{RGBColor @@ (#/255), Point[#]} &, ColorDot] ] Show[pic] ------------------------------------------------ But problem with this is that, to compute ColorDot vector .,,I started from mean, and took a positive and negative step( taken as stept above) to go forward and backward from mean,,,,,,,so ColorDot table has coordinates but some of those are negative..and So the above gives me half line and tat too just blue colored.... i get error Graphics::realu: Argument in expr is not a real number between 0 and 1. Thank You vicky Al Aisa