Can someone please explain this to me? I made these function animations with my professor and they were working in his office but when he emailed them to me the animation windows showed up blank and there was an error in the second animation. Can someone explain why this may be happening?
f[x_, t_, m_, n_, r_, A_] := 1 - m/(1 + Exp[-n (x + r*t)]) + A
Plot[f[x, 0, 4, 2, 1, 4], {x, -5, 5}, PlotRange -> {0, 6}]
Animate[Plot[f[x, t, 4, 2, 1, 4], {x, -5, 5}, PlotRange -> {0, 6}], {t, 0, 2}]
data = NDSolve[{D[u[t, x], t] == 0.2*u[t, x]*(f[x, t, 4, 2, 1, 4] - u[t, x]),
u[0, x] == 1 - 1/(1 + Exp[-x])}, u, {x, -10, 10}, {t, 0, 2}]
Animate[Show[
Plot[f[x, t, 4, 2, 1, 4], {x, -4, 4}, PlotRange -> {0, 6},
PlotStyle -> {Thickness[0.01]}],
Plot[u[t, x] /. data, {x, -4, 4}, PlotRange -> {0, 6}]
], {t, 0, 2}]

fis a pretty common symbol to use as a custom/temporary function. You probably had a previous definition forf(ordata, which is equally common) which interfered with the animation.Quitthe kernel and try again. – rm -rf♦ Dec 11 '12 at 2:55