Re: Something very simple.....

*To*: mathgroup at smc.vnet.net*Subject*: [mg87115] Re: [mg87103] Something very simple.....*From*: "Maarten van der Burgt" <maarten.vanderburgt at icos.be>*Date*: Tue, 1 Apr 2008 05:18:36 -0500 (EST)

Steve, Try, Sphere@@#&/@sphlst and, Complement[lsta,lsta[[lstb]]] maarten Steve Gray <stevebg@roadr To: mathgroup at smc.vnet.net unner.com> cc: Subject: [mg87103] Something very simple..... 01/04/2008 10:19 1. I have a list of sphere centers and radii like this: sphlst={{{ 5.11, 0.76, -0.32}, 100.39}, {{ 7.18, -1.86, -8.19}, 98.02}, {{26.71, -9.30, -6.85}, 111.27}, {{ 0, 0, 0}, 100.00}, {{ 8.65, 4.28, -3.81}, 103.87}}. If I do Map[Sphere,sphlst] I get too many braces, like this: {Sphere[{{ 5.11, 0.76, -0.32}, 100.39}], Sphere[{{ 7.18, -1.86, -8.19}, 98.02}], Sphere[{{26.71, -9.30, -6.85}, 111.27}], Sphere[{{ 0, 0, 0}, 100.00}], Sphere[{{ 8.65, 4.28, -3.81}, 103.87}]} and Sphere needs for example Sphere[{1.11, 2.22, 3.33},4.5]. What simple thing am I missing to remove the extra braces? (I know I can use Table but isn't there a "one-step" method?) Flatten doesn't seem to be useful here, or I'm using it wrong. 2. I have two lists, lsta={a,b,c,d,e,f} and lstb={1,3,4}. I want the elements of lsta that do NOT correspond to elements of lstb, in this case everything from lsta except elements 1,3, and 4: result={b,e,f}. (lstb won't have entries larger than Length[lsta]). Thanks for any tips. Steve Gray