ODE System Solution Maple: Plotting Earth's Orbit with Sun at Origin

[incredibe1999]

Hey there! I was trying to plot a ODE solution, but am not getting what I should be. It is actually plotting the orbit of Earth with Sun at the origin.
My equations

The (-0.00011847) is GM.
The Initial Conditions:

The plot I get:

Should not I be getting a elliptic/circular plot as the orbital positions of the Earth? Also, here the period is t=1. The position is supposed to be same at t=0 and t=1. Help, please!

 

[scottdave]

What is the code you used to generate this plot?

 

[incredibe1999]

What is the code you used to generate this plot?

I used the ODE Analyzer.

 

[BvU]

Well, that is not very helpful for us in finding out what goes wrong.

If I use your picture (please post something one can copy as text next time -- it avoids typos) but take different values, even good old Euler in Excel gets me a plot I expect:

values:

dt 0,01
x_0 1
y_0 0
vx_0 0
vy_0 1
GM 1

so the expressions look OK (provided I reproduced them correctly)

Now: what are the units for your values (and for time) ?