Add arrow to parametric plot

Question

I'm trying to add arrow to a simple parametric plot I'm doing:

F=1.85;
c=1.85;
G=0.01;
sol = NDSolve[{x'[t]==v[t], v'[t]==-v[t]+c Tanh[v[t]/F]-G Sign[x[t]],x[0]==0,v[0]==0.01},{x,v},{t,0,10}];
ParametricPlot[Evaluate[{x[t], v[t]} /. sol], {t, 0, 10}]

I've added the arrows. There is some similar question here in the forum, Adding arrows in curves however it is not with parametric plot, and works with ListPlot, I'm new in mathematica and don't find my way with this yet, any help or guidance would be much appreciated.

Your list of differential equations is bad-constructed, second item is not an equation. — rhermans, Nov 11 '15 at 08:10
@SjoerdC.deVries, can u post an example? maybe also address my question... — jarhead, Nov 11 '15 at 08:26
I corrected the post, now with the parametric plot ( typed a different plot before) — jarhead, Nov 11 '15 at 08:27
All I (and rhermans too) was saying is that the second term in the NDSolve, v'[t]+c Tanh[v[t]/F]-G Sign[x[t]] is not an equation because it doesn't have a ==. — Sjoerd C. de Vries, Nov 11 '15 at 08:32
Just add /. Line[x_] :> {Arrowheads[Table[.05, {5}]], Arrow[x]} after the ParametricPlot (as in the accepted answer in the question you linked to). I've checked it, and it works here too. — Sjoerd C. de Vries, Nov 11 '15 at 08:44

Alexei Boulbitch · Accepted Answer · 2018-05-05T21:23:02.997

Try this:

    F = 1.85;
c = 1.85;
G = 0.01;
sol = NDSolve[{x'[t] == v[t], 
    v'[t] == -v[t] + c Tanh[v[t]/F] - G Sign[x[t]], x[0] == 0, 
    v[0] == 0.01}, {x, v}, {t, 0, 10}];

ParametricPlot[Evaluate[{x[t], v[t]} /. sol], {t, 0, 10}] /. 
 Line[x_] :> {Arrowheads[{0., 0.07, 0.07, 0.07, 0.}], Arrow[x]}

and play with the list under the Arrowheads to adjust the number and position of the arrows:

or alternatively you may use the following strategy:

    Show[{
  ParametricPlot[Evaluate[{x[t], v[t]} /. sol], {t, 0, 1}, 
    PlotRange -> {-0.01, 0.01}] /. 
   Line[x_] :> {Arrowheads[{0.07}], Arrow[x]},
  ParametricPlot[Evaluate[{x[t], v[t]} /. sol], {t, 1, 2}],
  ParametricPlot[Evaluate[{x[t], v[t]} /. sol], {t, 2, 3}] /. 
   Line[x_] :> {Arrowheads[{0.07}], Arrow[x]},
  ParametricPlot[Evaluate[{x[t], v[t]} /. sol], {t, 3, 4}]
  }]

giving this:

Have fun!

Add arrow to parametric plot

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