Re: boolean variable with contours

*To*: mathgroup at smc.vnet.net*Subject*: [mg110714] Re: boolean variable with contours*From*: Peter Pein <petsie at dordos.net>*Date*: Sat, 3 Jul 2010 08:17:21 -0400 (EDT)*References*: <201007011234.IAA18567@smc.vnet.net>

Am Fri, 2 Jul 2010 06:54:31 +0000 (UTC) schrieb maria giovanna dainotti <mariagiovannadainotti at yahoo.it>: > Dear Math Group, > I have the following problem when I do a contourplot I can't use > the boolean variabile. This is the function for which I would like > to have the contours > > R1=1.029 > R2=2.92 > R3 > e1=300 > e2=1 > e3=100 > i=pi/12 > > =C2 ContourPlot[]==0==Im[y,{x,-2,2 },{y,-20,20}] > > > Thanks a lot for your help > Maria Hi Maria, 1.) pi is just any variable; I guess you want Pi (with capital P) and the Re[] around x/"real valued constant" is superfluous. 2.) what exactly do you expect from a call to Contourplot with three expressions (not wrapped by a list). Did you want ParametricPlot3D (which looks quite boring). Are the three expressions part of a vector and you want the norm? That would lead to a few vertical stripes. 3.) It could speed thing up to throw FullSimplify once onto the expression(s) to be plotted: In[1]:= R1=1029/1000; R2=292/100; R3; e1=300; e2=1; e3=100; i=Pi/12; vec=FullSimplify[{ 2*R3*Sin[ArcCos[Re[x/R3]]]*e3+2*R2/Cos[i]*Sin[ArcCos[Re[x/R2]]]*(e2-e3)+2*R= 1/Cos[i]*Sin[ArcCos[Re[x/R1]]]*(e1-e2),(2*R3*Sin[ArcCos[Re[x/R3]]]*e3+2*R2/= Cos[i]*Sin[ArcCos[Re[x/R2]]]*(e2-e3))*(Boole[-R2<x<-R1]+Boole[R2>x>R1]),2*R= 3*Sin[ArcCos[Re[x/R3]]]*e3*(Boole[x<-R2]+Boole[x>R2])+R3*Cos[ArcSin[y/R3]]}= ,{x,y}\[Element]Reals] Out[8]= {200 Sqrt[400-x^2]+(299 Sqrt[1058841-1000000 x^2]-3960 Sqrt[5329-625 x^2])/(125 (Sqrt[2]+Sqrt[6])),4/25 (1250 Sqrt[400-x^2]-99 Sqrt[(-2+Sqrt[3]) (-5329+625 x^2)]) (Boole[73/25>x>1029/1000]+Boole[-(73/25)<x<-(1029/1000)]),Sqrt[400-y^2]+200 Sqrt[400-x^2] (Boole[25 x>73]+Boole[x<-(73/25)])} Peter P.S.: Claws-Mail opened this again; maybe I forgot to send it maybe this posting comes twice. In the latter case: my apologies to the brave moderator.