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