C C .................................................................. C C SUBROUTINE DQHSG C C PURPOSE C TO COMPUTE THE VECTOR OF INTEGRAL VALUES FOR A GIVEN C GENERAL TABLE OF ARGUMENT, FUNCTION, FIRST DERIVATIVE, C AND SECOND DERIVATIVE VALUES. C C USAGE C CALL DQHSG (X,Y,FDY,SDY,Z,NDIM) C C DESCRIPTION OF PARAMETERS C X - DOUBLE PRECISION INPUT VECTOR OF ARGUMENT VALUES. C Y - DOUBLE PRECISION INPUT VECTOR OF FUNCTION VALUES. C FDY - DOUBLE PRECISION INPUT VECTOR OF FIRST DERIVATIVE. C SDY - DOUBLE PRECISION INPUT VECTOR OF SECOND DERIVATIVE. C Z - RESULTING DOUBLE PRECISION VECTOR OF INTEGRAL C VALUES. Z MAY BE IDENTICAL WITH X, Y, FDY OR SDY. C NDIM - THE DIMENSION OF VECTORS X,Y,FDY,SDY,Z. C C REMARKS C NO ACTION IN CASE NDIM LESS THAN 1. C C SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED C NONE C C METHOD C BEGINNING WITH Z(1)=0, EVALUATION OF VECTOR Z IS DONE BY C MEANS OF HERMITEAN SIXTH ORDER INTEGRATION FORMULA. C FOR REFERENCE, SEE C R.ZURMUEHL, PRAKTISCHE MATHEMATIK FUER INGENIEURE UND C PHYSIKER, SPRINGER, BERLIN/GOETTINGEN/HEIDELBERG, 1963, C PP.227-230. C C .................................................................. C SUBROUTINE DQHSG(X,Y,FDY,SDY,Z,NDIM) C C DIMENSION X(1),Y(1),FDY(1),SDY(1),Z(1) DOUBLE PRECISION X,Y,FDY,SDY,Z,SUM1,SUM2 C SUM2=0.D0 IF(NDIM-1)4,3,1 C C INTEGRATION LOOP 1 DO 2 I=2,NDIM SUM1=SUM2 SUM2=.5D0*(X(I)-X(I-1)) SUM2=SUM1+SUM2*((Y(I-1)+Y(I))+.4D0*SUM2*((FDY(I-1)-FDY(I))+ 1 .16666666666666667D0*SUM2*(SDY(I-1)+SDY(I)))) 2 Z(I-1)=SUM1 3 Z(NDIM)=SUM2 4 RETURN END