On Mon, Apr 21, 2025 at 4:22 AM Thierry Dumont <[email protected]> wrote:
> Mhh, interesting. > > In the REPL it works: > A=matrix([[0,0,0,0],[1/2,0,0,0],[0,1/2,0,0],[0,0,1,0]])*AA.one() > ok > and: > sage: A.parent().is_exact() > True > > But an other problem happens: > The class "RungeKutta" (the parent class of RK4) as a test: > > class RungeKutta(SageObject): > def __init__(self,A,B,Title,C=[]): > if not A.parent().is_exact(): > <raise an Exception"> > > and I get the exception, which seems to mean that, seen from the > RungeKutta class the parent af A is not exact. > > Then putting a > print(A.parent()) > just before the test in the constructor of RungeKutta, I get: > > Full MatrixSpace of 4 by 4 dense matrices over Real Double Field > > which, for me, is very surprising... why ? > > Thank you! > > thierry > > > Le 21/04/2025 à 11:05, [email protected] a écrit : > > Hi, > > I would do > > A=matrix([[0,0,0,0],[1/2,0,0,0],[0,1/2,0,0],[0,0,1,0]])*AA.one() > > B=vector([1/6,2/6,2/6,1/6])*AA.one() > > Best, Pedro > > > > El lun, 21 abr 2025 a las 10:35, Thierry Dumont (<[email protected] > > lyon1.fr <mailto:[email protected]>>) escribió: > > > > May be this problem is trivial (RTFM...) but: > > > > 1) Suppose I run this in the REPL: > > > > from sage.all import * > > from rkkit.RKRungeKutta import * #my code > > class RK4(RungeKutta): > > def __init__(self): > > title="Classical Runge-Kutta 4 explicit method" > > A=matrix(AA,[[0,0,0,0],[1/2,0,0,0],[0,1/2,0,0],[0,0,1,0]]) > > B=vector(AA,[1/6,2/6,2/6,1/6]) > > super().__init__(A,B,title) > > > > > > then I can do: > > > > R=RK4() > > everything is ok. > > > > 2) Now, in a directory "methods" I put the same piece of code as > above > > in a file called "RK4.py". > > > > I add a file __init__.py in methods/, which is: > > > > from sage.all import * > > from rkkit.RKRungeKutta import * > > __all__=["RK4"] > > > > So, I have > > methods/ > > __init__.py > > RK4.py > > > > Now, typing: > > > > from methods import * > > R=RK4.RK4() > > > > I get the error message: > > > > typeError: Illegal initializer for algebraic number > > > > How can I avoid this? > > > > (something like putting Integer() around the elements of the list in > > matrix(AA,[[0,0,0,0],[1/2,0,0,0],[0,1/2,0,0],[0,0,1,0]]) > > is something I want (need) to avoid). > > > > Yours, > > Thierry > > > > -- > > You received this message because you are subscribed to the Google > > Groups "sage-support" group. > > To unsubscribe from this group and stop receiving emails from it, > > send an email to [email protected] > > <mailto:sage-support%[email protected]>. > > To view this discussion visit https://groups.google.com/d/msgid/ > > sage-support/9fbe6b5b-1bd1-4bf2-bc66-ee0ff7343826%40math.univ- > > lyon1.fr <https://groups.google.com/d/msgid/sage- > > support/9fbe6b5b-1bd1-4bf2-bc66-ee0ff7343826%40math.univ-lyon1.fr>. > > > > -- > > You received this message because you are subscribed to the Google > > Groups "sage-support" group. > > To unsubscribe from this group and stop receiving emails from it, send > > an email to [email protected] <mailto:sage- > > [email protected]>. > > To view this discussion visit https://groups.google.com/d/msgid/sage- > > support/ > > CAOAJP6qRM47LOaFx_nQhmubGELzfj_f8ASkQfP%3D5aZkG2DOSdA%40mail.gmail.com > > <https://groups.google.com/d/msgid/sage-support/ > > CAOAJP6qRM47LOaFx_nQhmubGELzfj_f8ASkQfP%3D5aZkG2DOSdA%40mail.gmail.com? > > utm_medium=email&utm_source=footer>. > > -- > You received this message because you are subscribed to the Google Groups > "sage-support" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion visit > https://groups.google.com/d/msgid/sage-support/b5590e4a-7628-4782-9bde-0cc96f39151b%40math.univ-lyon1.fr > . > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/sage-support/CAAWYfq3AnHmLEh%3Dnt5ifY96T1EFJwD82Rs-TEOCmPmZ2MUvznQ%40mail.gmail.com.
