Hi, do you know why this code is not working?
Manipulate[
Module[{dt, n, t, theta, omega, thetaData},
dt = 0.01;(*Tamaño del paso de tiempo*)
n = 2000;(*Número de pasos de tiempo*)t = Table[i*dt, {i, 0, n}];
thetaData = {theta0};
theta = theta0;(*Inicializar theta*)
omega = 0;(*Inicializar omega*)(*Simulación del movimiento del \
péndulo*)Do[omega = omega - (g/l)*Sin[theta] - rozamiento*omega*dt;
theta = theta + omega*dt;
thetaData = Append[thetaData, theta], {i, 1, n}];
(*Gráfico del péndulo*)
Graphics[{Line[{{0,
0}, {l*Sin[thetaData[[r]]], -l*Cos[thetaData[[r]]]}}], {Red,
Disk[{0, 0}, 0.03]}, {Black,
Disk[{l*Sin[thetaData[[r]]], -l*Cos[thetaData[[r]]]},
0.1 Power[(30 m)/(4 \[Pi]), (3)^-1]]}},
PlotRange -> {{-3.4, 3.4}, {-3.4, 0.5}},
ImageSize -> {250, 250}]], {{theta0, \[Pi]/3.,
"Ángulo inicial \[Theta](0)"}, \[Pi]/16., \[Pi]/2.,
Appearance -> "Labeled"}, Delimiter, {{m, 4, "Masa m"}, 1, 15, 0.01,
Appearance -> "Labeled"}, {{l, 2.25, "Longitud L"}, 1, 3, 0.01,
Appearance -> "Labeled"}, {{rozamiento, 0, "Fuerza de Rozamiento"},
0, 1, 0.01, Appearance -> "Labeled"}, {{r, 1, "Controles"}, 1, 2001,
1, ControlType -> Slider},
TrackedSymbols :> {theta0, m, l, rozamiento, r}]