Dense univariate polynomials over \(\RR\), implemented using MPFR

TESTS:

Check that operations with numpy elements work well (see trac ticket #18076 and trac ticket #8426):

sage: import numpy
sage: x = polygen(RR)
sage: x * numpy.int32('1')
x
sage: numpy.int32('1') * x
x
sage: x * numpy.int64('1')
x
sage: numpy.int64('1') * x
x
sage: x * numpy.float32('1.5')
1.50000000000000*x
sage: numpy.float32('1.5') * x
1.50000000000000*x
class sage.rings.polynomial.polynomial_real_mpfr_dense.PolynomialRealDense

Bases: sage.rings.polynomial.polynomial_element.Polynomial

TESTS:

sage: f = RR['x'].random_element()
sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: isinstance(f, PolynomialRealDense)
True
change_ring(R)

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RR['x'], [-2, 0, 1.5])
sage: f.change_ring(QQ)
3/2*x^2 - 2
sage: f.change_ring(RealField(10))
1.5*x^2 - 2.0
sage: f.change_ring(RealField(100))
1.5000000000000000000000000000*x^2 - 2.0000000000000000000000000000
degree()

Return the degree of the polynomial.

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RR['x'], [1, 2, 3]); f
3.00000000000000*x^2 + 2.00000000000000*x + 1.00000000000000
sage: f.degree()
2

TESTS:

sage: type(f.degree())
<type 'sage.rings.integer.Integer'>
integral()

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RR['x'], [3, pi, 1])
sage: f.integral()
0.333333333333333*x^3 + 1.57079632679490*x^2 + 3.00000000000000*x
list()

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RR['x'], [1, 0, -2]); f
-2.00000000000000*x^2 + 1.00000000000000
sage: f.list()
[1.00000000000000, 0.000000000000000, -2.00000000000000]
quo_rem(other)

Return the quotient with remainder of self by other.

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RR['x'], [-2, 0, 1])
sage: g = PolynomialRealDense(RR['x'], [5, 1])
sage: q, r = f.quo_rem(g)
sage: q
x - 5.00000000000000
sage: r
23.0000000000000
sage: q*g + r == f
True
sage: fg = f*g
sage: fg.quo_rem(f)
(x + 5.00000000000000, 0)
sage: fg.quo_rem(g)
(x^2 - 2.00000000000000, 0)

sage: f = PolynomialRealDense(RR['x'], range(5))
sage: g = PolynomialRealDense(RR['x'], [pi,3000,4])
sage: q, r = f.quo_rem(g)
sage: g*q + r == f
True

TESTS:

Check that trac ticket #18467 is fixed:

sage: S.<x> = RR[]
sage: z = S.zero()
sage: z.degree()
-1
sage: q, r = z.quo_rem(x)
sage: q.degree()
-1
reverse()

Returns \(x^d f(1/x)\) where \(d\) is the degree of \(f\).

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RR['x'], [-3, pi, 0, 1])
sage: f.reverse()
-3.00000000000000*x^3 + 3.14159265358979*x^2 + 1.00000000000000
shift(n)

Returns this polynomial multiplied by the power \(x^n\). If \(n\) is negative, terms below \(x^n\) will be discarded. Does not change this polynomial.

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RR['x'], [1, 2, 3]); f
3.00000000000000*x^2 + 2.00000000000000*x + 1.00000000000000
sage: f.shift(10)
3.00000000000000*x^12 + 2.00000000000000*x^11 + x^10
sage: f.shift(-1)
3.00000000000000*x + 2.00000000000000
sage: f.shift(-10)
0

TESTS:

sage: f = RR['x'](0)
sage: f.shift(3).is_zero()
True
sage: f.shift(-3).is_zero()
True
truncate(n)

Returns the polynomial of degree \(< n\) which is equivalent to self modulo \(x^n\).

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RealField(10)['x'], [1, 2, 4, 8])
sage: f.truncate(3)
4.0*x^2 + 2.0*x + 1.0
sage: f.truncate(100)
8.0*x^3 + 4.0*x^2 + 2.0*x + 1.0
sage: f.truncate(1)
1.0
sage: f.truncate(0)
0
truncate_abs(bound)

Truncate all high order coefficients below bound.

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import PolynomialRealDense
sage: f = PolynomialRealDense(RealField(10)['x'], [10^-k for k in range(10)])
sage: f
1.0e-9*x^9 + 1.0e-8*x^8 + 1.0e-7*x^7 + 1.0e-6*x^6 + 0.000010*x^5 + 0.00010*x^4 + 0.0010*x^3 + 0.010*x^2 + 0.10*x + 1.0
sage: f.truncate_abs(0.5e-6)
1.0e-6*x^6 + 0.000010*x^5 + 0.00010*x^4 + 0.0010*x^3 + 0.010*x^2 + 0.10*x + 1.0
sage: f.truncate_abs(10.0)
0
sage: f.truncate_abs(1e-100) == f
True
sage.rings.polynomial.polynomial_real_mpfr_dense.make_PolynomialRealDense(parent, data)

EXAMPLES:

sage: from sage.rings.polynomial.polynomial_real_mpfr_dense import make_PolynomialRealDense
sage: make_PolynomialRealDense(RR['x'], [1,2,3])
3.00000000000000*x^2 + 2.00000000000000*x + 1.00000000000000