Coverage for local/lib/python2.7/site-packages/sage/geometry/polyhedron/base_RDF.py : 100%

""" 

Base class for polyhedra over ``RDF``. 

""" 

from __future__ import absolute_import 

from sage.rings.all import RDF 

from .base import Polyhedron_base 

class Polyhedron_RDF(Polyhedron_base): 

""" 

Base class for polyhedra over ``RDF``. 

TESTS:: 

sage: p = Polyhedron([(0,0)], base_ring=RDF); p 

A 0-dimensional polyhedron in RDF^2 defined as the convex hull of 1 vertex 

sage: TestSuite(p).run() 

""" 

# 1e-6 is the cddf+ default fuzzy zero cutoff 

def _is_zero(self, x): 

""" 

Test whether ``x`` is zero. 

INPUT: 

- ``x`` -- a number in the base ring. 

OUTPUT: 

Boolean. 

EXAMPLES:: 

sage: p = Polyhedron([(0,0)], base_ring=RDF) 

sage: p._is_zero(0) 

True 

sage: p._is_zero(1e-3) 

False 

This is a fuzzy zero for floating-point numbers:: 

sage: p._is_zero(1e-10) 

True 

""" 

return abs(x)<=1e-6 

def _is_nonneg(self, x): 

""" 

Test whether ``x`` is nonnegative. 

INPUT: 

- ``x`` -- a number in the base ring. 

OUTPUT: 

Boolean. 

EXAMPLES:: 

sage: p = Polyhedron([(0,0)], base_ring=RDF) 

sage: p._is_nonneg(1) 

True 

sage: p._is_nonneg(-1e-3) 

False 

This is a fuzzy zero for floating-point numbers:: 

sage: p._is_nonneg(-1e-10) 

True 

""" 

return x>=-1e-6 

def _is_positive(self, x): 

""" 

Test whether ``x`` is positive. 

INPUT: 

- ``x`` -- a number in the base ring. 

OUTPUT: 

Boolean. 

EXAMPLES:: 

sage: p = Polyhedron([(0,0)], base_ring=RDF) 

sage: p._is_positive(1) 

True 

sage: p._is_positive(0) 

True 

This is a fuzzy zero for floating-point numbers:: 

sage: p._is_positive(-1e-10) 

True 

""" 

return x>=-1e-6 

_base_ring = RDF