Re: pole/zero plot for TransferFunctionModel in the control system package?

*To*: mathgroup at smc.vnet.net*Subject*: [mg125436] Re: pole/zero plot for TransferFunctionModel in the control system package?*From*: Suba Thomas <subat at wolfram.com>*Date*: Wed, 14 Mar 2012 00:35:31 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com

That is a good candidate for a Properties and Relations example. If you just want the open-loop poles and open-loop zeros, RootLocusPlot could be made more efficient. RootLocusPlot[ k*((s^2 + 2*s + 4)/(s*(s + 4)*(s + 6)*(s^2 + 1.4*s + 1))), {k, 0, 1}, Method -> "GenericSolve", PlotStyle -> None, PoleZeroMarkers -> {Automatic, None, Automatic}, PlotPoints -> 2, MaxRecursion -> 0, PlotRange -> All] Suba Thomas Wolfram Research Bob Hanlon wrote: > Using RootLocusPlot the open - loop poles, closed - loop poles, and > open - loop zeros are marked using "\[FilledSmallCircle]", "*", and > "\[SmallCircle]", respectively > > RootLocusPlot[k*((s^2 + 2*s + 4)/ > (s*(s + 4)*(s + 6)* > (s^2 + 1.4*s + 1))), > {k, 0, 150}] > > > Bob Hanlon > > On Mon, Mar 12, 2012 at 5:07 AM, Nasser M. Abbasi <nma at 12000.org> wrote: > >> I was looking at the functions in the control systems, which >> were added in V 8, and there seems to be a missing an important >> plot function to generate automatically a map of the locations >> of the poles and zeros for a transfer function (continuous or >> discrete time). >> >> Unless I overlooked it, I hope this will be added in V 9. >> >> I know I can generate such a plot myself by some extra coding, >> but I think a build-in function to do this would be a better solution >> similar to all the other useful standard control systems plot functions >> listed here >> >> http://reference.wolfram.com/mathematica/guide/ClassicalAnalysisAndDesign.html >> >> Another software has this function as standard in their control >> systems toolbox and it is called pzmap (for googling and >> reference to what this command do). >> >> thanks, >> --Nasser >> >> >> > > > >