Extract equalities from a list of assumptions
Hi, how can I recognize an equality from an inequality, in a list of assumptions?
sage: var('a,b') sage: eq1 = a == b sage: eq2 = a < b
sage: eq1.operator() == operator.eq True
sage: eq2.operator() == operator.lt True
operator is a python module and the comparison operators are lt (less than), le (lesser or equal), eq (equal), ne (different), gt (greater than) and ge (greater or equal).
To complement @vdelecroix answer, the assumptions is a list of symbolic expressions which you can filter as follows:
sage: var('x,y') (x, y) sage: assume(x>0) sage: assume(x<=1) sage: assume(y==2) sage: equalities = [ass for ass in assumptions() if ass.operator() == operator.eq] sage: inequalities = [ass for ass in assumptions() if ass.operator() in [operator.lt, operator.le, operator.gt, operator.ge]] sage: equalities [y == 2] sage: inequalities [x > 0, x <= 1]
You might want to put
Asked: 2016-01-03 07:49:04 -0500
Seen: 46 times
Last updated: Jan 03 '16