Re: Number of zeros finite or infinite?
- To: mathgroup at smc.vnet.net
- Subject: [mg115436] Re: Number of zeros finite or infinite?
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Tue, 11 Jan 2011 00:33:57 -0500 (EST)
finiteQ[expr_] := FreeQ[expr, Element[_, Integers]] Bob Hanlon ---- James <icorone at hotmail.com> wrote: ============= Hello everyone, I'm working on a program that deals with zeros of functions and would like to know if the zeros are finite or not. For example, in the finite case : testcase1 = Reduce[2*x^2 + 3*x - 1 == 0, x] x == (1/4)*(-3 - Sqrt[17]) || x == (1/4)*(-3 + Sqrt[17]) and in the infinite case for example, I would obtain something like: thezeros = Reduce[1 - 4*Sin[z]^2 == 0, z] Element[C[1], Integers] && (z == -(Pi/6) + 2*Pi*C[1] || z == (7*Pi)/6 + 2*Pi*C[1] || z == Pi/6 + 2*Pi*C[1] || z == (5*Pi)/6 + 2*Pi*C[1]) Can someone please help me distinguish the two cases so that I can then process them differently? For example, in pseudo code: If(finite) do onething, else doanotherthing Thanks guys,