Problems with Module
- To: mathgroup at smc.vnet.net
- Subject: [mg112052] Problems with Module
- From: Docente Sergio Miguel Terrazas Porras <sterraza at uacj.mx>
- Date: Fri, 27 Aug 2010 04:07:29 -0400 (EDT)
Hi!
The following is a slight modification of a code that works fine. But this
one does not work.
However, if I empty the list of local variables in Module, Then it works!
Could some of you enlighten me?
f[t_]:=4 Sin[t];g[t_]:=2 Cos[t];a=0;b=2\[Pi];
DerVectConst[f,g,a,b]
DerVectConst[f_,g_,a_,b_]:=Module[{r,vel,acel,unitario,derivadadeu,du},
$Assumptions=t\[Element]Reals;
r[t_]={f[t],g[t]};
vel[t_]=(r^\[Prime])[t];
acel[t_]=(r^\[DoublePrime])[t];
unitario[t_]=acel[t]/Norm[acel[t]];
derivadadeu[t_]=(unitario^\[Prime])[t];
du[t_]=derivadadeu[t]//FullSimplify;
Manipulate[
f1=Graphics[{Thick,Blue,Arrow[{r[t],r[t]+du[t]}]}];
f2=Graphics[{Thick,Green,Arrow[{r[t],r[t]+unitario[t]}]}];
g1=ParametricPlot[r[t],{t,a,b},AspectRatio->Automatic,PlotStyle->{Thick, Red}];
txt=Graphics[{Text[Style["\!\(\*OverscriptBox[\"u\",
\"^\"]\)",18,Bold],(r[t]+1.1unitario[t])],Text[Style["\!\(\*OverscriptBox[\"u\",
\"^\"]\)^\[Prime]",18,Bold],(r[t]+1.1du[t])]}];
punto=Graphics[{PointSize[.02],Point[r[t]]}];
Show[g1,f1,f2,txt,punto,PlotRange->All]
,{t,a,b}]
]