| HomepagePublicationsTalksTeXmacsMathemagix | 
      A holonomic function is an analytic function, which satisfies a linear
      differential equation with polynomial coefficients. In particular, the
      elementary functions 
, etc.
      and many special functions like 
,
      
, Bessel functions, etc. are
      holonomic functions.
    
      Given a holonomic function 
      (determined by the linear differential equation it satisfies and initial
      conditions in a non singular point 
),
      we show how to perform arbitrary precision evaluations of 
 at a non singular point 
 on the Riemann surface of 
, while estimating the error.
    
      Moreover, if the coefficients of the polynomials in the equation for
      
 are algebraic numbers, then
      our algorithm is asymptotically very fast: if 
 is the time needed to multiply two 
 digit numbers, then we need a time 
 to compute 
 digits of 
.
    
Note: this paper also occurred as appendix C in my PhD. and as a 1996 preprint.