On Tue, Jan 14, 2014 at 06:40:03PM +0000, Grace Roberts wrote: [...] > I've attached a quick print-screen of the code.
I've managed to have a look at the screenshot, there are no obvious problems, but I'm not a Scipy expert. If you do get an answer from a Scipy mailing list, I would really appreciate it if you were to write back here with an explanation. In the meantime, I have a couple of comments about your code. You initialise some constants like this: G = -6.67*10**-11 Mm = 6.4*10**23 You can write them more compactily as: G = -6.67e-11 Mm = 6.4e23 Notice that you have made G a negative value? That is unusual, normally G is quoted as a positive quantity, G = 6.67e-11 m³/(kg*s²), or the same value with units N (m/kg)². Either way, G is given a positive value. Possibly making G a negative quantity is causing the problems? Another minor comment on your code, in the f(x, t) function you have a line taking a square root: r = (x[0]**2 + x[2]**2)**0.5 You can improve the accuracy of that radius calculation by using the hypot function. First, at the top of the file, import the math module: import math Then inside the f(x,t) function change the calculation of r to this: r = math.hypot(x[0], x[2]) Hope this is helpful, -- Steven _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
