C HEPS 10
C ..................................................................HEPS 20
C HEPS 30
C SUBROUTINE HEPS HEPS 40
C HEPS 50
C PURPOSE HEPS 60
C COMPUTES THE VALUE OF AN N-TERM EXPANSION IN HERMITE HEPS 70
C POLYNOMIALS WITH COEFFICIENT VECTOR C FOR ARGUMENT VALUE X. HEPS 80
C HEPS 90
C USAGE HEPS 100
C CALL HEPS(Y,X,C,N) HEPS 110
C HEPS 120
C DESCRIPTION OF PARAMETERS HEPS 130
C Y - RESULT VALUE HEPS 140
C X - ARGUMENT VALUE HEPS 150
C C - COEFFICIENT VECTOR OF GIVEN EXPANSION HEPS 160
C COEFFICIENTS ARE ORDERED FROM LOW TO HIGH HEPS 170
C N - DIMENSION OF COEFFICIENT VECTOR C HEPS 180
C HEPS 190
C REMARKS HEPS 200
C OPERATION IS BYPASSED IN CASE N LESS THAN 1 HEPS 210
C HEPS 220
C SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED HEPS 230
C NONE HEPS 240
C HEPS 250
C METHOD HEPS 260
C DEFINITION HEPS 270
C Y=SUM(C(I)*H(I-1,X), SUMMED OVER I FROM 1 TO N). HEPS 280
C EVALUATION IS DONE BY MEANS OF UPWARD RECURSION HEPS 290
C USING THE RECURRENCE EQUATION FOR HERMITE POLYNOMIALS HEPS 300
C H(N+1,X)=2*(X*H(N,X)-N*H(N-1,X)). HEPS 310
C HEPS 320
C ..................................................................HEPS 330
C HEPS 340
SUBROUTINE HEPS(Y,X,C,N) HEPS 350
C HEPS 360
DIMENSION C(1) HEPS 370
C HEPS 380
C TEST OF DIMENSION HEPS 390
IF(N)1,1,2 HEPS 400
1 RETURN HEPS 410
C HEPS 420
2 Y=C(1) HEPS 430
IF(N-2)1,3,3 HEPS 440
C HEPS 450
C INITIALIZATION HEPS 460
3 H0=1. HEPS 470
H1=X+X HEPS 480
C HEPS 490
DO 4 I=2,N HEPS 500
H2=X*H1-FLOAT(I-1)*H0 HEPS 510
H0=H1 HEPS 520
H1=H2+H2 HEPS 530
4 Y=Y+C(I)*H0 HEPS 540
RETURN HEPS 550
END HEPS 560