Select[ ] Woes: ÃÂÃÂSolved
- To: mathgroup at smc.vnet.net
- Subject: [mg83127] Select[ ] Woes: ÃÂÃÂSolved
- From: Bruce Colletti <vze269bv at verizon.net>
- Date: Mon, 12 Nov 2007 05:13:34 -0500 (EST)
The code below answers my earlier posting. Although the ratio of lists A and B looks like a list of rationals, FullForm reveals otherwise. In turn, because it's not working with numbers, Select returns an empty list.
Bruce
A = {Item[3, Background -> Red], Item[4, Background -> Green]};
B = {Item[7, Background -> White], Item[10, Background -> Blue]};
x = A/B
FullForm[A/B]
Select[x, # > 0 &]
{3/7, 4/10}
List[Times[Item[3, Rule[Background, RGBColor[1, 0, 0]]],
Power[Item[7, Rule[Background, GrayLevel[1]]], -1]],
Times[Item[4, Rule[Background, RGBColor[0, 1, 0]]],
Power[Item[10, Rule[Background, RGBColor[0, 0, 1]]], -1]]]
{}