Hi! On 06/27/2011 07:09 AM, J Sage wrote:
... series(sqrt(x),x,0,3) = series(sqrt(y^2),y,0,3*2) = y = x^(1/2).
Note that the member functions degree() and ldegree() currently return int, so this would have to be generalized somehow, when implementing Puiseux series directly in GiNaC.
Bye -richy. -- Richard B. Kreckel <http://www.ginac.de/~kreckel/ <http://www.ginac.de/%7Ekreckel/>>
Actually, ginac cannot do a series on x^n or on sqrt(x^2). Here's the ginsh output:
series(x^n,x,1); (0^n)+Order(x) series(x^n,x,2); power::eval(): division by zero series(sqrt(x^2),x,3); power::eval(): division by zero
Oh, you're so right! Actually, that's because the result of series(sqrt(x^2),x==0,3) is not necessarly x: it could just as well be -x. The presence of the branch point makes it more tricky. Sorry for not being able to help. Bye -richy. -- Richard B. Kreckel <http://www.ginac.de/~kreckel/>