Hello, For polynomial equations, the following should work in general.
sage: R.<x,y> = CC['x','y'] sage: f = x-y sage: g = x^2 - y^2 sage: I = R.ideal([f]).radical() sage: g in I True In general, to see if the equation g == 0 is implied by the equations f1==0, f2==0, ..., fn==0 you can do I = R.ideal([f1, f2, ..., fn]).radical() g in I and sage should appropriately return True or False. I should mention that I don't actually use this very much, so there may be some caveats that I'm not aware of. -Jason On 09/03/2010 12:30 PM, tvn wrote: > Hi, I wonder if there's any 'imply' kind of function in Sage ? For > example > > eq1 = x -y == 0 > eq2 = x^2 - y^2 == 0 > > eq1 implies eq2 (but not the other way around). > > > If no then is there any efficient way to do it ? one way I can > think of (that might not work) is get the factor_list of eq1 and > eq2 , if eq2 has a factor that is the same as eq1 then eq1 implies > eq2 -- something like that. > -- To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
