*DECK QELG SUBROUTINE QELG (N, EPSTAB, RESULT, ABSERR, RES3LA, NRES) C***BEGIN PROLOGUE QELG 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 SINGLE 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 Real 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 - Real 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 - Real C Resulting approximation to the integral C C ABSERR - Real C Estimate of the absolute error computed from C RESULT and the 3 previous results C C RES3LA - Real 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 C***SEE ALSO QAGIE, QAGOE, QAGPE, QAGSE C***ROUTINES CALLED R1MACH C***REVISION HISTORY (YYMMDD) C 800101 DATE WRITTEN C 890531 Changed all specific intrinsics to generic. (WRB) C 890531 REVISION DATE from Version 3.2 C 891214 Prologue converted to Version 4.0 format. (BAB) C 900328 Added TYPE section. (WRB) C***END PROLOGUE QELG