On Aug 15, 10:00 am, David Joyner <wdjoy...@gmail.com> wrote: > On Mon, Aug 15, 2011 at 9:56 AM, linouc <linzhenhua...@gmail.com> wrote: > > Hello, Sage groups, I have a problem, please see the example below, I > > wonder anyone can help me solve this problem: > > > f = Piecewise([[(0,pi/2),-1],[(pi/2,pi),2]]) > > a=pi*integrate(f,x,0,pi) > > a.show() > > b=pi*integrate(sin(x),x,0,pi) > > b.show() > > integrate(f*sin(x),x,0,pi) > > I'm guessing that your error means that > multiplication of a piecewise times a symbolic function > has not been implemented: > > sage: f = Piecewise([[(0,pi/2),-1],[(pi/2,pi),2]]) > sage: f*sin(x)
> > AttributeError: 'sage.symbolic.expression.Expression' object has no > > attribute 'domain' David is correct. This is only a symptom of the real problem, which is an outdated (though still quite functional and useful for its purposes) piecewise class. Using piecewise functions by themselves is pretty coherent, but the rest of Sage has made a lot of progress since then. Unfortunately, we haven't had any developer with all three of the time, motivation, and expertise to do this. We would welcome any contributions to improve this! - kcrisman -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
