Re: Manipulate / Space Phasor

*To*: mathgroup at smc.vnet.net*Subject*: [mg92331] Re: Manipulate / Space Phasor*From*: "David Park" <djmpark at comcast.net>*Date*: Sat, 27 Sep 2008 22:22:05 -0400 (EDT)*References*: <gbl2ve$lvl$1@smc.vnet.net>

The Presentations package at my web site ($50) has an Arrow3D routine. In the Presentations graphics paradigm it is very easy to combine various curves and objects in a graphic - you just draw one thing after another. (Also in your Manipulate plot the PlotRange should be explicitly specified so that each frame will have the same plot range.) So here is your helix with an arrow with a Red tip going from the origin to the tip of the curve. In this case I used an "Absolute" scaling so the arrowcone would always be the same size. Needs["Presentations`Master`"] Manipulate[ Draw3DItems[ {ParametricDraw3D[{Sin[u], Cos[u], u/10}, {u, 0, t}], Red, Arrow3D[{0, 0, 0}, {Sin[t], Cos[t], t/10}, {.2, .7, "Absolute"}]}, PlotRange -> {{-1, 1}, {-1, 1}, {0, 2}}, Axes -> True], Style["Helix with Arrow to Tip", 16], Delimiter, {t, 1, 20, Appearance -> "Labeled"}] -- David Park djmpark at comcast.net http://home.comcast.net/~djmpark/ "Fabian" <fabian.uriarte at gmail.com> wrote in message news:gbl2ve$lvl$1 at smc.vnet.net... > Dear Group- > > In this plot: > > Manipulate[ > ParametricPlot3D[{Sin[u], Cos[u], u/10}, {u, 0, t}], {t, 1, 20}] > > Is there a way a to show an Arrow from the origin to the tip of the > curve at all instances of time t? > > Thank you. >