Re: An Elegant way of plotting the Pole-Zero diagram

*To*: mathgroup at smc.vnet.net*Subject*: [mg88856] Re: An Elegant way of plotting the Pole-Zero diagram*From*: Szabolcs Horvát <szhorvat at gmail.com>*Date*: Mon, 19 May 2008 05:18:08 -0400 (EDT)*Organization*: University of Bergen*References*: <g0p49o$nc2$1@smc.vnet.net>

bk2005usa at gmail.com wrote: > Hi to All: > > Would anyone care to provide an elegant way of plotting the pole-zero > diagram of a transfer function H[s], using the conventional symbols, > namely, "x" for poles and "0" for zeros. Mathematica does not have a > built-in function to draw those symbols---like "Point[] and > PointSize[]. Here are two functions for those symbols: zero[pt_, size_: 10] := Circle[pt, Offset[size/2 {1, 1}]] pole[pt_, size_: 10] := Line[Map[Offset[size/2 #, pt] &, {{{1, 1}, {-1, -1}}, {{-1, 1}, {1, -1}}}, {2}]] The size is specified in printer's points, i.e. it stays constant while resizing the plot.