Re: ParametricPlot3D - plane appears contracted in some directions

*To*: mathgroup at smc.vnet.net*Subject*: [mg108986] Re: ParametricPlot3D - plane appears contracted in some directions*From*: Narasimham <mathma18 at hotmail.com>*Date*: Fri, 9 Apr 2010 03:32:22 -0400 (EDT)*References*: <hopv0d$r6p$1@smc.vnet.net>

On Mar 29, 3:22 pm, nevjernik <hajde... at mijenjamo.planetu> wrote: > Consider following simple piece of code which should represent plane > determined by two vectors: > > ******* Code Start ********** > vector1 = {1, 2, 3} > vector2 = {2, 3, 4} > ParametricPlot3D[{u vector1 + v vector2}, {u, -10, 10}, {v, -10, 10}] > ******* Code End ************ > > Question: Why with this code I get some kind of "deformed" plane > apparently contracted in some directions, in a sense that distances of > points doesn't appear equal in all directions. > > It can be better seen with circle of radius 2 drawn in that plane: > > ******* Code Start ********** > vector1 = {1, 2, 3} > vector2 = {2, 3, 4} > Show[ParametricPlot3D[{u vector1 + v vector2}, {u, -10, 10}, {v, -10, > 10}, AxesOrigin -> {0, 0, 0}], > ParametricPlot3D[2 Cos[t] vector1 + 2 Sin[t] vector2, {t, 0, 2 Pi}, > PlotStyle -> {Thick, Green}]] > > ******* Code End ************ > > I tried to use options like PlotRange, or BoxRatios, but with no efect > on plane or circle. > > What I am doing wrong or missing? > > Thanks In ParametricPlot3D three components are needed. So better: vector1 = {1, 2, 3} ; vector2 = {2, 3, 4} ;Plot3D[{u vector1 + v vector2}, {u, -10, 10}, {v, -10, 10}] Narasimham