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15 (* This file was automatically generated: do not edit *********************)
19 (* $Id: CPoly_Degree.v,v 1.5 2004/04/23 10:00:53 lcf Exp $ *)
21 include "algebra/CPoly_NthCoeff.ma".
23 include "algebra/CFields.ma".
25 (*#* *Degrees of Polynomials
26 ** Degrees of polynomials over a ring
28 Let [R] be a ring and write [RX] for the ring of polynomials
38 cic:/CoRN/algebra/CPoly_Degree/Degree_def/R.var
44 Notation RX := (cpoly_cring R).
50 The length of a polynomial is the number of its coefficients. This is
51 a syntactical property, as the highest coefficient may be [0]. Note that
52 the `zero' polynomial [cpoly_zero] has length [0],
53 a constant polynomial has length [1] and so forth. So the length
54 is always [1] higher than the `degree' (assuming that the highest
55 coefficient is [[#]Zero])!
58 inline procedural "cic:/CoRN/algebra/CPoly_Degree/lth_of_poly.con" as definition.
61 When dealing with constructive polynomials, notably over the reals or
62 complex numbers, the degree may be unknown, as we can not decide
63 whether the highest coefficient is [[#]Zero]. Hence,
64 degree is a relation between polynomials and natural numbers; if the
65 degree is unknown for polynomial [p], degree(n,p) doesn't hold for
66 any [n]. If we don't know the degree of [p], we may still
67 know it to be below or above a certain number. E.g. for the polynomial
68 $p_0 +p_1 X +\cdots + p_{n-1} X^{n-1}$#p0 +p1 X + ... + p(n-1)
69 X^(n-1)#, if $p_i \mathrel{\#}0$#pi apart from 0#, we can say that the
70 `degree is at least [i]' and if $p_{j+1} = \ldots =p_n =0$#p(j+1)
71 = ... =pn =0# (with [n] the length of the polynomial), we can say
72 that the `degree is at most [j]'.
75 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le.con" as definition.
77 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree.con" as definition.
79 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic.con" as definition.
81 inline procedural "cic:/CoRN/algebra/CPoly_Degree/odd_cpoly.con" as definition.
83 inline procedural "cic:/CoRN/algebra/CPoly_Degree/even_cpoly.con" as definition.
85 inline procedural "cic:/CoRN/algebra/CPoly_Degree/regular.con" as definition.
92 Implicit Arguments degree_le [R].
96 Implicit Arguments degree [R].
100 Implicit Arguments monic [R].
104 Implicit Arguments lth_of_poly [R].
112 cic:/CoRN/algebra/CPoly_Degree/Degree_props/R.var
118 Notation RX := (cpoly_cring R).
123 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_wd.con" as lemma.
125 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_wd.con" as lemma.
127 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_wd.con" as lemma.
129 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_imp_degree_le.con" as lemma.
131 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_c_.con" as lemma.
133 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_c_.con" as lemma.
135 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_c_one.con" as lemma.
137 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_x_.con" as lemma.
139 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_x_.con" as lemma.
141 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_x_.con" as lemma.
143 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_mon.con" as lemma.
145 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_inv.con" as lemma.
147 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_plus.con" as lemma.
149 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_minus.con" as lemma.
151 inline procedural "cic:/CoRN/algebra/CPoly_Degree/Sum_degree_le.con" as lemma.
153 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_inv.con" as lemma.
155 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_plus_rht.con" as lemma.
157 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_minus_lft.con" as lemma.
159 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_plus.con" as lemma.
161 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_minus.con" as lemma.
163 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_mult.con" as lemma.
165 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_mult_aux.con" as lemma.
168 Hint Resolve degree_mult_aux: algebra.
171 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_mult.con" as lemma.
173 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_nexp.con" as lemma.
175 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_nexp.con" as lemma.
177 inline procedural "cic:/CoRN/algebra/CPoly_Degree/lt_i_lth_of_poly.con" as lemma.
179 inline procedural "cic:/CoRN/algebra/CPoly_Degree/poly_degree_lth.con" as lemma.
181 inline procedural "cic:/CoRN/algebra/CPoly_Degree/Cpoly_ex_degree.con" as lemma.
183 inline procedural "cic:/CoRN/algebra/CPoly_Degree/poly_as_sum''.con" as lemma.
186 Hint Resolve poly_as_sum'': algebra.
189 inline procedural "cic:/CoRN/algebra/CPoly_Degree/poly_as_sum'.con" as lemma.
191 inline procedural "cic:/CoRN/algebra/CPoly_Degree/poly_as_sum.con" as lemma.
193 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_zero.con" as lemma.
195 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_1_imp.con" as lemma.
197 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_cpoly_linear.con" as lemma.
199 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_cpoly_linear.con" as lemma.
201 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_one.con" as lemma.
203 inline procedural "cic:/CoRN/algebra/CPoly_Degree/monic_apzero.con" as lemma.
210 Hint Resolve poly_as_sum'' poly_as_sum' poly_as_sum: algebra.
214 Hint Resolve degree_mult_aux: algebra.
218 Section degree_props_Field
221 (*#* ** Degrees of polynomials over a field
222 %\begin{convention}% Let [F] be a field and write [FX] for the ring of
223 polynomials over [F].
228 cic:/CoRN/algebra/CPoly_Degree/degree_props_Field/F.var
234 Notation FX := (cpoly_cring F).
239 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_mult.con" as lemma.
241 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_nexp.con" as lemma.
243 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_le_mult_imp.con" as lemma.
245 inline procedural "cic:/CoRN/algebra/CPoly_Degree/degree_mult_imp.con" as lemma.
248 End degree_props_Field