Example of a set with grading#
- sage.categories.examples.sets_with_grading.Example[source]#
alias of
NonNegativeIntegers
- class sage.categories.examples.sets_with_grading.NonNegativeIntegers[source]#
Bases:
UniqueRepresentation
,Parent
Non negative integers graded by themselves.
EXAMPLES:
sage: E = SetsWithGrading().example(); E Non negative integers sage: E in Sets().Infinite() True sage: E.graded_component(0) {0} sage: E.graded_component(100) {100}
>>> from sage.all import * >>> E = SetsWithGrading().example(); E Non negative integers >>> E in Sets().Infinite() True >>> E.graded_component(Integer(0)) {0} >>> E.graded_component(Integer(100)) {100}
- an_element()[source]#
Return 0.
EXAMPLES:
sage: SetsWithGrading().example().an_element() 0
>>> from sage.all import * >>> SetsWithGrading().example().an_element() 0
- generating_series(var='z')[source]#
Return \(1 / (1-z)\).
EXAMPLES:
sage: N = SetsWithGrading().example(); N Non negative integers sage: f = N.generating_series(); f 1/(-z + 1) sage: LaurentSeriesRing(ZZ,'z')(f) 1 + z + z^2 + z^3 + z^4 + z^5 + z^6 + z^7 + z^8 + z^9 + z^10 + z^11 + z^12 + z^13 + z^14 + z^15 + z^16 + z^17 + z^18 + z^19 + O(z^20)
>>> from sage.all import * >>> N = SetsWithGrading().example(); N Non negative integers >>> f = N.generating_series(); f 1/(-z + 1) >>> LaurentSeriesRing(ZZ,'z')(f) 1 + z + z^2 + z^3 + z^4 + z^5 + z^6 + z^7 + z^8 + z^9 + z^10 + z^11 + z^12 + z^13 + z^14 + z^15 + z^16 + z^17 + z^18 + z^19 + O(z^20)