Re: a' vs a and a vs a' looks different in streamplot

• To: mathgroup at smc.vnet.net
• Subject: [mg99658] Re: [mg99627] a' vs a and a vs a' looks different in streamplot
• From: sean k <sean_incali at yahoo.com>
• Date: Sun, 10 May 2009 05:17:56 -0400 (EDT)

```I recognize I only gave one equation with 2 unknowns. That's not the issue though.  Let's say the system was...

a'[t]== -a[t] -kr -b[t]
b'[t]== -a[t]

And we want to look at the vectorfields. When I plot the a' vs a or a vs a' I get two entirely different plots. (not just 90 rotation of each other)

--- On Sat, 5/9/09, sean_incali at yahoo.com <sean_incali at yahoo.com> wrote:

> From: sean_incali at yahoo.com <sean_incali at yahoo.com>
> Subject: [mg99627] a' vs a and a vs a' looks different in streamplot
> To: mathgroup at smc.vnet.net
> Date: Saturday, May 9, 2009, 12:31 AM
> Consider the following.
>
> a'[t]= -a[t] -kr -b[t]
>
> Let us plot the vectorfields of a' vs a. (or a vs
> a' for that matter)
> as follows.
>
> Manipulate[{StreamPlot[{a, -a - kr b}, {a, -10, 10}, {b,
> -10, 10},
>    FrameLabel -> {a, a'}],
>   StreamPlot[{-a - kr b, a}, {a, -10, 10}, {b, -10, 10},
>    FrameLabel -> {a', a}]}, {kr, 0, 10}]
>
> Why do the plots of " a vs. a' " and "
> a' vs. a " look so different?
> They aren't just 90' rotation of each other.
>
> Shouldn't they be?
>
> Thanks for any insight.
>
> Sean

```

• Prev by Date: Re: Manipulate Issue - resend with code
• Next by Date: Re: Manipulate Issue - resend with code
• Previous by thread: Re: a' vs a and a vs a' looks different in streamplot
• Next by thread: Getting Workbench to Work