2021-12-20 20:58:10 +0200 received badge ● Notable Question (source) 2020-10-07 22:17:57 +0200 received badge ● Popular Question (source) 2019-06-12 21:23:50 +0200 received badge ● Good Question (source) 2019-04-18 19:52:12 +0200 received badge ● Popular Question (source) 2017-11-24 10:59:24 +0200 received badge ● Nice Question (source) 2017-02-13 07:20:44 +0200 received badge ● Famous Question (source) 2016-04-29 10:14:37 +0200 commented answer Coercion on continued fractions Alright, done. 2016-04-27 15:50:37 +0200 received badge ● Notable Question (source) 2016-04-27 15:48:01 +0200 commented answer Coercion on continued fractions I have already implemented an algorithm performing a Mobius transformation on an input continued fraction. My goal is to call the corresponding method upon a * continued_fraction(x) or continued_fraction(x) * a, where a is an integer, or continued_fraction(x) + continued_fraction(y). I apologize if the wording of my question was confusing. Can you provide any advice, please? 2016-04-26 17:00:45 +0200 commented question Coercion on continued fractions @triviality: But this soultion would work only for cases where the first operand is a continued fraction, wouldn't it? Or modifying all the classes whose objects a continued fraction can be added, multiplied by.... 2016-04-21 12:58:22 +0200 received badge ● Good Question (source) 2016-04-20 20:43:04 +0200 commented answer Coercion on continued fractions "It does not make much sense to mix these considerations with arithmetic." I am not sure I understand your point. Can you please explain what considerations do you mean? "There is a ticket for that purpose: #19120" Yes, I know, this is the ticket I have been working on. Do you have any idea how to make it work, please? 2016-04-20 19:20:54 +0200 received badge ● Nice Question (source) 2016-04-17 14:49:52 +0200 asked a question Coercion on continued fractions Currently, when user types sage: x = continued_fraction(pi) sage: y = 3*x  an TypeError is raised saying TypeError: unsupported operand parent(s) for '*': 'Integer Ring' and ''  I understand that Sage tries to find common parent of Integer element and ContinuedFraction_real and fails. It seems that continued fractions in Sage are not implemented as elements of any particular field, and are derived directly from SageObject. I am implementing an algorithm for arithmetical operations on continued fractions. Is it possible to make Sage call a particular method when the user tries to perform an arithmetical binary operation, where one of the operands is a continued fraction? I have found those 1, 2, 3 links, but it seems that the topic of coercion is rather extensive and I don't know what to look for, as I don't know what the correct solution to the problem is. Thank you for any response! 2016-02-29 14:50:16 +0200 commented answer Implementing new CF class advice What would be the proper way to implement Homography class? Where should I put it? 2016-02-26 14:50:40 +0200 commented answer Implementing new CF class advice This is great advice, thank you. 2016-02-26 11:43:17 +0200 received badge ● Supporter (source) 2016-02-26 10:19:29 +0200 received badge ● Popular Question (source) 2016-02-26 07:29:45 +0200 asked a question Implementing new CF class advice My goal is to implement Gosper's algorithm for algebraic operations on continued fractions into Sage. To begin with, I would like to implement a functionality to perform a homographic transformation $$x \rightarrow \frac{ax + b}{cx + d}$$ where $x$ is a CF. The easiest way to do this is probably to create a new class in sage.rings.continued_fraction that would on inicialization accept the integer constants $a, b, c, d$ and a descendant of ContinuedFraction_base class. The most important method of this class would be next() or _iter_(), which would read the input $x$ until it can output new term using Gosper's algorithm. How do I create an instance of this class with proper arguments, when for example $(3*x + 1)/2$, where $x$ is a CF, is called from Sage? (Instead of _mul_() being called, than _add_() and so on...) Simplifying using inbuilt Sage methods and then evaluating the expression as a string using regular expressions somehow (like this) might be a solution, but I am not sure if the best one. Thank you very much for any advice on this! EDIT: I have found this promising link, but haven't found anything useful in there so far... 2015-12-28 14:57:53 +0200 commented answer Add a row / column to a matrix Note that insert_row method is not implemented for rational matrices. 2015-12-27 13:30:26 +0200 received badge ● Scholar (source) 2015-12-22 17:52:28 +0200 received badge ● Student (source) 2015-12-22 17:40:11 +0200 asked a question Add a row / column to a matrix What is the most efficient way to add a row / column to an existing matrix? Are there any handy functions for this? I couldn't find any and any way I can think of seems needlessly complicated... Thanks! 2015-08-01 11:17:45 +0200 received badge ● Editor (source) 2015-08-01 10:13:44 +0200 asked a question Configuring Sage project in PyCharm What is the correct PyCharm configuration for the Sage project? I use Python 2.7.6, source path sage/src (added to PYTHONPATH) and even though Sage compiles and runs almost all doctests, I keep getting unresolved references error in PyCharm. Do you have any ideas what is wrong with this? Examples of unresolved references are: from integer import Integer from real_mpfi import RealIntervalField from sage.rings.real_mpfr import RR