ASKSAGE: Sage Q&A Forum - Latest question feedhttp://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Mon, 26 Aug 2019 20:53:01 -0500How can I solve line equation in SageMath?http://ask.sagemath.org/question/47606/how-can-i-solve-line-equation-in-sagemath/So we know we got standard 2D line equation that looks like `y=a*x+b`. And now I want to solve the `a,b` by given a few points. How can I achieve it?
I remember I've seen the solution somewhere, but I just can't find it out now. andrewygMon, 26 Aug 2019 20:53:01 -0500http://ask.sagemath.org/question/47606/finding the derivative of a functional w.r.t a functionhttp://ask.sagemath.org/question/32876/finding-the-derivative-of-a-functional-wrt-a-function/ I've defined a system as:
var('a, t');
function('x, y');
de1 = diff(x(t),t) == y(t);
de2 = diff(y(t),t) == -a*x(t) - (a-4)/a*y(t) - y(t)^3;
I'd like to compute the derivatives of the rhs of de1 and de2 w.r.t to x(t) and y(t) (to eventually form a Jacobian matrix), i.e. the derivative of the rhs of de1 w.r.t to x(t) is Zero and w.r.t y(t) is 1. I've tried the following:
diff(de1.rhs(),y);
diff(de1.rhs(),y(t));
derivative(de1.rhs(),y(t));
I get errors on all three. I'd appreciate any help. thank you.
sophiaThu, 24 Mar 2016 01:50:20 -0500http://ask.sagemath.org/question/32876/Manipulations with symbolic functionshttp://ask.sagemath.org/question/24114/manipulations-with-symbolic-functions/Hello! I'm trying to migrate to Sage from Maple and facing some difficulties with symbolic manipulations, which is the most important part of my work. For example, I want to define the following equality:
N(t + delta * t, A) = ( N(t, A + sigma * sqrt(delta * t)) * (1 - p(t, A))
+ N(t, A - sigma * sqrt(delta * t)) * p(t, A) )
where the function N(t,A) is yet unknown, and I can't find a way to to do correctly. After that I want to manipulate this equality, for example by substituting Taylor series of N instead of it. In Maple this whole thing is very straightforward, but I really can't find a way to do the same in Sage. Any help will be much appreciated.
StanislavSun, 14 Sep 2014 09:03:39 -0500http://ask.sagemath.org/question/24114/