Re: Coefficient Question
- To: mathgroup at smc.vnet.net
- Subject: [mg104051] Re: Coefficient Question
- From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
- Date: Sat, 17 Oct 2009 07:02:13 -0400 (EDT)
- References: <200910161119.HAA01303@smc.vnet.net>
On 16 Oct 2009, at 20:19, Scott wrote: > I've got the expression > > 8(3+5k+4x1+6x2+45x3) > > and I want to extract the constant 24. > > Yes, I can define a function and then set k and x1 and x2 and x3 to 0 > but there has to be easier way, no? > > Any suggestions? > > Thanks much. > > Cheers, Scott > Well, you could always do: f = 8 (3 + 5 k + 4 x1 + 6 x2 + 45 x3) First[CoefficientArrays[f, Variables[f]]] 24 Though actually whether that is actually in any sense "easier" than f /. Thread[Variables[f] -> 0] 24 seems doubtful to me. Andrzej Kozlowski
- References:
- Coefficient Question
- From: Scott <sguthery@gmail.com>
- Coefficient Question