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4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
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15 (* This file was automatically generated: do not edit *********************)
19 (* $Id: PowerSeries.v,v 1.8 2004/04/23 10:01:08 lcf Exp $ *)
21 (*#* printing Exp %\ensuremath{\exp}% *)
23 (*#* printing Sin %\ensuremath{\sin}% *)
25 (*#* printing Cos %\ensuremath{\cos}% *)
27 (*#* printing Log %\ensuremath{\log}% *)
29 (*#* printing Tan %\ensuremath{\tan}% *)
33 (*#* *More on Power Series
35 We will now formally define an operator that defines a function as the
36 sum of some series given a number sequence. Along with it, we will
37 prove some important properties of these entities.
44 (*#* **General results
46 %\begin{convention}% Let [J : interval] and [x0 : IR] be a point of [J].
52 cic:/CoRN/transc/PowerSeries/Power_Series/J.var
56 cic:/CoRN/transc/PowerSeries/Power_Series/x0.var
60 cic:/CoRN/transc/PowerSeries/Power_Series/Hx0.var
64 cic:/CoRN/transc/PowerSeries/Power_Series/a.var
67 inline procedural "cic:/CoRN/transc/PowerSeries/FPowerSeries.con" as definition.
70 The most important convergence criterium specifically for power series
71 is the Dirichlet criterium.
77 cic:/CoRN/transc/PowerSeries/Power_Series/Ha.var
80 inline procedural "cic:/CoRN/transc/PowerSeries/Power_Series/r.con" "Power_Series__" as definition.
82 inline procedural "cic:/CoRN/transc/PowerSeries/Power_Series/Hr.con" "Power_Series__" as definition.
86 inline procedural "cic:/CoRN/transc/PowerSeries/Dirichlet_crit.con" as lemma.
89 When defining a function using its Taylor series as a motivation, the following operator can be of use.
92 inline procedural "cic:/CoRN/transc/PowerSeries/FPowerSeries'.con" as definition.
95 This function is also continuous and has a good convergence ratio.
98 inline procedural "cic:/CoRN/transc/PowerSeries/FPowerSeries'_cont.con" as lemma.
100 inline procedural "cic:/CoRN/transc/PowerSeries/included_FPowerSeries'.con" as lemma.
105 cic:/CoRN/transc/PowerSeries/Power_Series/Ha'.var
110 inline procedural "cic:/CoRN/transc/PowerSeries/FPowerSeries'_conv'.con" as lemma.
112 inline procedural "cic:/CoRN/transc/PowerSeries/FPowerSeries'_conv.con" as lemma.
119 Hint Resolve FPowerSeries'_cont: continuous.
123 Section More_on_PowerSeries
127 %\begin{convention}% Let [F] and [G] be the power series defined
128 respectively by [a] and by [fun n => (a (S n))].
133 cic:/CoRN/transc/PowerSeries/More_on_PowerSeries/x0.var
137 cic:/CoRN/transc/PowerSeries/More_on_PowerSeries/a.var
142 inline procedural "cic:/CoRN/transc/PowerSeries/More_on_PowerSeries/F.con" "More_on_PowerSeries__" as definition.
144 inline procedural "cic:/CoRN/transc/PowerSeries/More_on_PowerSeries/G.con" "More_on_PowerSeries__" as definition.
151 cic:/CoRN/transc/PowerSeries/More_on_PowerSeries/Hf.var
155 cic:/CoRN/transc/PowerSeries/More_on_PowerSeries/Hf'.var
159 cic:/CoRN/transc/PowerSeries/More_on_PowerSeries/Hg.var
164 (*#* We get a comparison test for power series. *)
166 inline procedural "cic:/CoRN/transc/PowerSeries/FPowerSeries'_comp.con" as lemma.
168 (*#* And a rule for differentiation. *)
174 inline procedural "cic:/CoRN/transc/PowerSeries/Derivative_FPowerSeries1'.con" as lemma.
177 End More_on_PowerSeries
184 (*#* **Function definitions through power series
186 We now define the exponential, sine and cosine functions as power
187 series, and prove their convergence. Tangent is defined as the
188 quotient of sine over cosine.
191 inline procedural "cic:/CoRN/transc/PowerSeries/Exp_ps.con" as definition.
193 inline procedural "cic:/CoRN/transc/PowerSeries/sin_seq.con" as definition.
195 inline procedural "cic:/CoRN/transc/PowerSeries/sin_ps.con" as definition.
197 inline procedural "cic:/CoRN/transc/PowerSeries/cos_seq.con" as definition.
199 inline procedural "cic:/CoRN/transc/PowerSeries/cos_ps.con" as definition.
201 inline procedural "cic:/CoRN/transc/PowerSeries/Exp_conv'.con" as lemma.
203 inline procedural "cic:/CoRN/transc/PowerSeries/Exp_conv.con" as lemma.
205 inline procedural "cic:/CoRN/transc/PowerSeries/sin_conv.con" as lemma.
207 inline procedural "cic:/CoRN/transc/PowerSeries/cos_conv.con" as lemma.
209 inline procedural "cic:/CoRN/transc/PowerSeries/Expon.con" as definition.
211 inline procedural "cic:/CoRN/transc/PowerSeries/Sine.con" as definition.
213 inline procedural "cic:/CoRN/transc/PowerSeries/Cosine.con" as definition.
215 inline procedural "cic:/CoRN/transc/PowerSeries/Tang.con" as definition.
218 Some auxiliary domain results.
221 inline procedural "cic:/CoRN/transc/PowerSeries/Exp_domain.con" as lemma.
223 inline procedural "cic:/CoRN/transc/PowerSeries/sin_domain.con" as lemma.
225 inline procedural "cic:/CoRN/transc/PowerSeries/cos_domain.con" as lemma.
227 inline procedural "cic:/CoRN/transc/PowerSeries/included_Exp.con" as lemma.
229 inline procedural "cic:/CoRN/transc/PowerSeries/included_Sin.con" as lemma.
231 inline procedural "cic:/CoRN/transc/PowerSeries/included_Cos.con" as lemma.
234 Definition of the logarithm.
237 inline procedural "cic:/CoRN/transc/PowerSeries/log_defn_lemma.con" as lemma.
239 inline procedural "cic:/CoRN/transc/PowerSeries/Logarithm.con" as definition.
246 Hint Resolve included_Exp included_Sin included_Cos: included.
250 As most of these functions are total, it makes sense to treat them as setoid functions on the reals. In the case of logarithm and tangent, this is not possible; however, we still define some abbreviations for aesthetical reasons.
253 inline procedural "cic:/CoRN/transc/PowerSeries/Exp.con" as definition.
255 inline procedural "cic:/CoRN/transc/PowerSeries/Sin.con" as definition.
257 inline procedural "cic:/CoRN/transc/PowerSeries/Cos.con" as definition.
259 inline procedural "cic:/CoRN/transc/PowerSeries/Log.con" as definition.
261 inline procedural "cic:/CoRN/transc/PowerSeries/Tan.con" as definition.