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SUBROUTINE DQHFE

PURPOSE
   TO COMPUTE THE VECTOR OF INTEGRAL VALUES FOR A GIVEN
   EQUIDISTANT TABLE OF FUNCTION AND DERIVATIVE VALUES.

USAGE
   CALL DQHFE (H,Y,DERY,Z,NDIM)

DESCRIPTION OF PARAMETERS
   H	  - DOUBLE PRECISION INCREMENT OF ARGUMENT VALUES.
   Y	  - DOUBLE PRECISION INPUT VECTOR OF FUNCTION VALUES.
   DERY   - DOUBLE PRECISION INPUT VECTOR OF DERIVATIVE VALUES.
   Z	  - RESULTING DOUBLE PRECISION VECTOR OF INTEGRAL
	    VALUES. Z MAY BE IDENTICAL WITH Y OR DERY.
   NDIM   - THE DIMENSION OF VECTORS Y,DERY,Z.

REMARKS
   NO ACTION IN CASE NDIM LESS THAN 1.

SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED
   NONE

METHOD
   BEGINNING WITH Z(1)=0, EVALUATION OF VECTOR Z IS DONE BY
   MEANS OF HERMITEAN FOURTH ORDER INTEGRATION FORMULA.
   FOR REFERENCE, SEE
   (1) F.B.HILDEBRAND, INTRODUCTION TO NUMERICAL ANALYSIS,
       MCGRAW-HILL, NEW YORK/TORONTO/LONDON, 1956, PP.314-319.
   (2) R.ZURMUEHL, PRAKTISCHE MATHEMATIK FUER INGENIEURE UND
       PHYSIKER, SPRINGER, BERLIN/GOETTINGEN/HEIDELBERG, 1963,
       PP.227-230.