diff --git a/src/sage/rings/complex_double.pyx b/src/sage/rings/complex_double.pyx index bc9018790e4..9deff3dd145 100644 --- a/src/sage/rings/complex_double.pyx +++ b/src/sage/rings/complex_double.pyx @@ -97,6 +97,7 @@ import real_mpfr RR = real_mpfr.RealField() from real_double import RealDoubleElement, RDF +from sage.rings.integer_ring import ZZ from sage.structure.parent_gens import ParentWithGens @@ -1432,6 +1433,22 @@ cdef class ComplexDoubleElement(FieldElement): """ return True + def is_integer(self): + """ + Returns True if this number is a integer + + EXAMPLES:: + + sage: CDF(0.5).is_integer() + False + sage: CDF(I).is_integer() + False + sage: CDF(2).is_integer() + True + """ + return (self.real() in ZZ) and (self.imag()==0) + + def _pow_(self, ComplexDoubleElement a): """ The function returns the complex number `z` raised to the