80
Part B Complex Asymptotics * Chapter 4: Complex Analysis * Chapter 5: Rational and Meromorphic Asymptotics * Chapter 6: Singularity Analysis of GFs *Chapter 7: Applications of Singularity Analysis *Chapter 8: Saddle-point Methods 1 Wednesday, June 2, 2010

Part B Complex Asymptotics - algo.inria.fralgo.inria.fr/flajolet/Publications/Slides/Bologna2.pdf · Trees with a finite set of node degrees Excursions with finite set of steps

Embed Size (px)

Citation preview

Part BComplex Asymptotics

* Chapter 4: Complex Analysis* Chapter 5: Rational and Meromorphic Asymptotics* Chapter 6: Singularity Analysis of GFs*Chapter 7: Applications of Singularity Analysis*Chapter 8: Saddle-point Methods

1Wednesday, June 2, 2010

N! for N=2,...,50

2Wednesday, June 2, 2010

Real analysis?

3Wednesday, June 2, 2010

4Wednesday, June 2, 2010

(Catalan GF)

5Wednesday, June 2, 2010

CHAPTER

6Wednesday, June 2, 2010

7Wednesday, June 2, 2010

8Wednesday, June 2, 2010

9Wednesday, June 2, 2010

10Wednesday, June 2, 2010

Complex analysis: LOCAL vs GLOBAL

11Wednesday, June 2, 2010

Complex analysis: coeffs at 0 ~> elsewhere

12Wednesday, June 2, 2010

singularity

13Wednesday, June 2, 2010

14Wednesday, June 2, 2010

Exponential growth of coefficients

15Wednesday, June 2, 2010

Exponential order of coeffs is computable:

16Wednesday, June 2, 2010

TRAINS

17Wednesday, June 2, 2010

Chapter 5Rational and Meromorphic Asymptotics

18Wednesday, June 2, 2010

19Wednesday, June 2, 2010

20Wednesday, June 2, 2010

Schur:21Wednesday, June 2, 2010

22Wednesday, June 2, 2010

23Wednesday, June 2, 2010

24Wednesday, June 2, 2010

Worked out Example: derangements

25Wednesday, June 2, 2010

26Wednesday, June 2, 2010

27Wednesday, June 2, 2010

28Wednesday, June 2, 2010

SCHEMA

29Wednesday, June 2, 2010

Chapter 6Singularity Analysis

30Wednesday, June 2, 2010

31Wednesday, June 2, 2010

32Wednesday, June 2, 2010

(earlier: Darboux-Pólya; Tauberian thms)

33Wednesday, June 2, 2010

34Wednesday, June 2, 2010

35Wednesday, June 2, 2010

36Wednesday, June 2, 2010

37Wednesday, June 2, 2010

38Wednesday, June 2, 2010

39Wednesday, June 2, 2010

THEOREMS 1+2

40Wednesday, June 2, 2010

EGF

41Wednesday, June 2, 2010

42Wednesday, June 2, 2010

43Wednesday, June 2, 2010

44Wednesday, June 2, 2010

45Wednesday, June 2, 2010

46Wednesday, June 2, 2010

Chapter 7Applications of Singularity

Analysis

47Wednesday, June 2, 2010

48Wednesday, June 2, 2010

49Wednesday, June 2, 2010

50Wednesday, June 2, 2010

51Wednesday, June 2, 2010

functional equation

52Wednesday, June 2, 2010

53Wednesday, June 2, 2010

54Wednesday, June 2, 2010

55Wednesday, June 2, 2010

56Wednesday, June 2, 2010

selves

57Wednesday, June 2, 2010

58Wednesday, June 2, 2010

Exponential * nrational

59Wednesday, June 2, 2010

Trees with a finite set of node degrees

Excursions with finite set of steps [Lalley, BaFl]

Maps embedded into the plane [Tutte,...] Gimenez-Noy: Planar graphs

Context-free structures = Drmota-Lalley-Woods Thm.

APPLICATIONS of ALGEBRAIC FUNCTIONS

60Wednesday, June 2, 2010

61Wednesday, June 2, 2010

62Wednesday, June 2, 2010

63Wednesday, June 2, 2010

64Wednesday, June 2, 2010

Singularity Analysis applies to

non-linear ODEs = models of “logarithmic trees”

the holonomic framework = solutions of linear ODEs with rational coefficients.

65Wednesday, June 2, 2010

66Wednesday, June 2, 2010

67Wednesday, June 2, 2010

Conclusion:SCHEMAS

68Wednesday, June 2, 2010

Chapter 8Saddle-point Asymptotics

69Wednesday, June 2, 2010

Modulus of an analytic function70Wednesday, June 2, 2010

71Wednesday, June 2, 2010

Cauchy coefficient integrals

72Wednesday, June 2, 2010

Saddle-point method:

= concentration + local quadratic approximation.

73Wednesday, June 2, 2010

74Wednesday, June 2, 2010

75Wednesday, June 2, 2010

The saddle-point theorem:

under conditions: concentration + local quadratic approximation

+ Hayman: admissible functions= closure properties

76Wednesday, June 2, 2010

77Wednesday, June 2, 2010

Hardy & Ramanujan

78Wednesday, June 2, 2010

(double saddle-point)

Coalescence; e.g., maps

Gauss => Airy

79Wednesday, June 2, 2010

Applies to many entire functions: involutions, set partitions, etc.

Applies to function with violent growth at singularity(-ies): integer partitions

Applies to coefficients of large order in large powers

Conclusions: Saddle-point method

80Wednesday, June 2, 2010