2018-05-19 11:29:56 -0600 commented question Solving ODE using desolve_rk4 but th I'm not new to Sage but since I don't use it a lot I'm kinda an inexperienced user. But what I would do (whether on Sage or any other numerical package) is to find Temp(t), that is, find Temp as a function of 't' given the 't' and 'Temp' points you supplied as lists. I plotted your points and they represent a broken sinusoidal line, but there may be ways to find a reasonable expression for Temp(t). Then you would substitute Temp(t) in your code by the expression you found. 2018-05-19 10:45:50 -0600 commented answer Unexpected behaviour of arbitrary precision real numbers That worked, thanks! I was suspecting that the formatted print command should be blamed for that. Yet, the following two lines work nicely on Sage's notebook, too: W = RealField(200) print W.pi()  and repr() seems not to be necessary in this case. Too much to learn. :-) 2018-05-19 10:37:30 -0600 received badge ● Supporter (source) 2018-05-18 22:06:46 -0600 received badge ● Notable Question (source) 2018-05-18 19:29:08 -0600 received badge ● Editor (source) 2018-05-18 19:26:56 -0600 asked a question Unexpected behaviour of arbitrary precision real numbers I've been trying to use arbitrary precision real numbers and I'm a bit confused. The simple snippet below illustrates my point: R = RealField(200) z = R(2.0) print '%.20f' % (z.sqrt())  I should get (or that's what I was expecting) 1.41421356237309504880, but instead I got 1.41421356237309514547 (a disagreement in the last five decimal places). Where am I goofing up? You see, it's a quite simple code. How could I fix it in order to obtain the desired/expected result? Thanks in advance for any light shed on this matter. Fausto 2015-02-05 02:10:35 -0600 received badge ● Student (source) 2015-02-05 02:10:33 -0600 received badge ● Teacher (source) 2015-02-05 02:10:33 -0600 received badge ● Self-Learner (source) 2015-02-05 01:42:31 -0600 received badge ● Popular Question (source) 2015-02-02 19:42:15 -0600 answered a question list_plot() not working in a terminal session I found the solution for this problem. All I had to do was to replace the following line: list_plot(...) by the following two lines: p = list_plot(...) p.show() And then a plot was plotted. 2015-02-02 16:52:28 -0600 commented question Solving PDEs Hello, I assume you want to have your PDE(s) solved numerically. And I don't think SAGE is the best tool to accomplish that. You can certainly solve your PDE with SAGE, but you will have to put a lot of your own code together. If you want to solve equations like the above with less effort, may I suggest you to use FiPy, a PDE solver that uses the finite volume method (FVM). It has extensive documentation, several examples and a support list where developers and users will help you with your questions. Good luck! Fausto 2015-02-02 08:09:27 -0600 asked a question list_plot() not working in a terminal session Hello, list_plot() does not produce any plot when I run a script in a terminal (pure text) session. But it does when I run the same script in SAGE's graphical ("notebook()") environment. However, in both ways the execution ends normally (no error messages). Curiously, if I type list_plot(...array name goes here...) in the terminal after the execution of the aforementioned script, a plot is produced. Any explanation for that? The script is quite simple and short as shown below. Thanks for any help. import time from sage.all import * import math n = [19, 31, 61, 127] l=len(n) c = [] for i in range(l-1): for k in range(i+1,l): ai = 2**n[i]-1 ak = 2**n[k]-1 temp = ai*ak print ai, ak, ai*ak start_cpu = time.clock() divs = prime_divisors(temp) cpu_t = time.clock() - start_cpu c.append((math.log10(1.0*ai*ak),cpu_t)) print divs print 'CPU time = %.3e \n' % (cpu_t) list_plot(c)