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### How do you overlay trajectory graphs on vector fields?

Hi, I'm doing a programming problem where I have to graph a vector field, then overlay trajectory graphs with different initial values on it.

So far this is what I have:

var('R, S')

plot_vector_field([3R - R^2 - 2RS, 2S - S^2 - R*S], (R,-50, 50), (S, -50, 50))

R = sol[:,0]

S = sol[:,1]

list_plot(zip(R,S), plotjoined=True)**

The last line always produces a separate graph. I've tried using the "+" operator to "add" it to the vector field graph, but that gives me an error instead. I also don't know how to repeat the process (i.e. overlay additional trajectories) without having to make a new graph for each. Truth be told I'm only a beginning coder and have some trouble synthesizing different coding aspects together.

Any help would be greatly appreciated!

 2 No.2 Revision tmonteil 21128 ●25 ●153 ●391 http://wiki.sagemath.o...

### How do you overlay trajectory graphs on vector fields?

Hi, I'm doing a programming problem where I have to graph a vector field, then overlay trajectory graphs with different initial values on it.

So far this is what I have:

var('R, S')  plot_vector_field([3R S')
plot_vector_field([3*R - R^2 - 2RS, 2S 2*R*S, 2*S - S^2 - R*S], (R,-50, 50), (S, -50, 50))  50))
R = sol[:,0] sol[:,0]
S = sol[:,1] sol[:,1]
list_plot(zip(R,S), plotjoined=True)**plotjoined=True)


The last line always produces a separate graph. I've tried using the "+" operator to "add" it to the vector field graph, but that gives me an error instead. I also don't know how to repeat the process (i.e. overlay additional trajectories) without having to make a new graph for each. Truth be told I'm only a beginning coder and have some trouble synthesizing different coding aspects together.

Any help would be greatly appreciated!