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2012-10-31 21:38:33 +0100 commented question Do I have to restart the notebook everytime I build Sage?

No question is self-explanatory. If you cannot state your question in a self-contained body post and put your situation in context, then it is probably not a very useful question. Remember that the main purpose of the question title is for browsing the question index and letting readers decide *whether* to open the page or not. Once they've committed to opening it, they should get a proper body text.

2012-10-30 10:01:15 +0100 commented answer Restrict taylor() to only find genuine Taylor series

Oh, you mean just evaluate at zero? Yeah, that would probably have been much simpler from the start. D'oh :-)

2012-10-28 22:29:29 +0100 asked a question Solve equations integrally

Is it possible to solve polynomial equations over the integers in Sage?

For example, I want to find the integral solutions of x*y + y*z + z*x = 7 and x + y + z = 5. One possible solution is [x = 1, y = 1, z = 3], and there are only finitely many. Geometrically, I want to obtain the rational points on the intersection of a quadratic hypersurface and a couple of hyperplanes.

After some testing I have come to the conclusion that Maple cannot do this, but Mathematica does seem to be able to produce those solutions. However, I'm new to Sage and don't know if this is within its reach.

I would be very grateful for your help

2012-10-28 21:28:22 +0100 commented answer Restrict taylor() to only find genuine Taylor series

Oh, how about a multivariate series?

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2012-10-28 21:25:27 +0100 commented answer Restrict taylor() to only find genuine Taylor series

I guess that's a functional solution. Thanks.

2012-10-28 17:22:29 +0100 asked a question Restrict taylor() to only find genuine Taylor series

In Maple, the Taylor series command produces an error if the expression does not have a Taylor series, such as 1/x around x = 0. Is it possible to achieve the same effect in Sage? I have some rather long expressions, and it's not always immediately obvious whether there are some singular terms hidden in the result of .taylor().