SLATEC Routines --- DQELG ---

```*DECK DQELG
SUBROUTINE DQELG (N, EPSTAB, RESULT, ABSERR, RES3LA, NRES)
C***BEGIN PROLOGUE  DQELG
C***SUBSIDIARY
C***PURPOSE  The routine determines the limit of a given sequence of
C            approximations, by means of the Epsilon algorithm of
C            P.Wynn. An estimate of the absolute error is also given.
C            The condensed Epsilon table is computed. Only those
C            elements needed for the computation of the next diagonal
C            are preserved.
C***LIBRARY   SLATEC
C***TYPE      DOUBLE PRECISION (QELG-S, DQELG-D)
C***KEYWORDS  CONVERGENCE ACCELERATION, EPSILON ALGORITHM, EXTRAPOLATION
C***AUTHOR  Piessens, Robert
C             Applied Mathematics and Programming Division
C             K. U. Leuven
C           de Doncker, Elise
C             Applied Mathematics and Programming Division
C             K. U. Leuven
C***DESCRIPTION
C
C           Epsilon algorithm
C           Standard fortran subroutine
C           Double precision version
C
C           PARAMETERS
C              N      - Integer
C                       EPSTAB(N) contains the new element in the
C                       first column of the epsilon table.
C
C              EPSTAB - Double precision
C                       Vector of dimension 52 containing the elements
C                       of the two lower diagonals of the triangular
C                       epsilon table. The elements are numbered
C                       starting at the right-hand corner of the
C                       triangle.
C
C              RESULT - Double precision
C                       Resulting approximation to the integral
C
C              ABSERR - Double precision
C                       Estimate of the absolute error computed from
C                       RESULT and the 3 previous results
C
C              RES3LA - Double precision
C                       Vector of dimension 3 containing the last 3
C                       results
C
C              NRES   - Integer
C                       Number of calls to the routine
C                       (should be zero at first call)
C