C DA12 10
C ..................................................................DA12 20
C DA12 30
C SUBROUTINE DQA12 DA12 40
C DA12 50
C PURPOSE DA12 60
C TO COMPUTE INTEGRAL(EXP(-X)*FCT(X)/SQRT(X), SUMMED OVER X DA12 70
C FROM 0 TO INFINITY). DA12 80
C DA12 90
C USAGE DA12 100
C CALL DQA12 (FCT,Y) DA12 110
C PARAMETER FCT REQUIRES AN EXTERNAL STATEMENT DA12 120
C DA12 130
C DESCRIPTION OF PARAMETERS DA12 140
C FCT - THE NAME OF AN EXTERNAL DOUBLE PRECISION FUNCTION DA12 150
C SUBPROGRAM USED. DA12 160
C Y - THE RESULTING DOUBLE PRECISION INTEGRAL VALUE. DA12 170
C DA12 180
C REMARKS DA12 190
C NONE DA12 200
C DA12 210
C SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED DA12 220
C THE EXTERNAL DOUBLE PRECISION FUNCTION SUBPROGRAM FCT(X) DA12 230
C MUST BE FURNISHED BY THE USER. DA12 240
C DA12 250
C METHOD DA12 260
C EVALUATION IS DONE BY MEANS OF 12-POINT GENERALIZED GAUSS- DA12 270
C LAGUERRE QUADRATURE FORMULA, WHICH INTEGRATES EXACTLY DA12 280
C WHENEVER FCT(X) IS A POLYNOMIAL UP TO DEGREE 23. DA12 290
C FOR REFERENCE, SEE DA12 300
C SHAO/CHEN/FRANK, TABLES OF ZEROS AND GAUSSIAN WEIGHTS OF DA12 310
C CERTAIN ASSOCIATED LAGUERRE POLYNOMIALS AND THE RELATED DA12 320
C GENERALIZED HERMITE POLYNOMIALS, IBM TECHNICAL REPORT DA12 330
C TR00.1100 (MARCH 1964), PP.15-16. DA12 340
C DA12 350
C ..................................................................DA12 360
C DA12 370
SUBROUTINE DQA12(FCT,Y) DA12 380
C DA12 390
C DA12 400
DOUBLE PRECISION X,Y,FCT DA12 410
C DA12 420
X=.36191360360615602D2 DA12 430
Y=.33287369929782177D-15*FCT(X) DA12 440
X=.27661108779846090D2 DA12 450
Y=Y+.13169240486156340D-11*FCT(X) DA12 460
X=.21396755936166109D2 DA12 470
Y=Y+.60925085399751278D-9*FCT(X) DA12 480
X=.16432195087675313D2 DA12 490
Y=Y+.8037942349882859D-7*FCT(X) DA12 500
X=.12390447963809471D2 DA12 510
Y=Y+.43164914098046673D-5*FCT(X) DA12 520
X=.9075434230961203D1 DA12 530
Y=Y+.11377383272808760D-3*FCT(X) DA12 540
X=.63699753880306349D1 DA12 550
Y=Y+.16473849653768349D-2*FCT(X) DA12 560
X=.41984156448784132D1 DA12 570
Y=Y+.14096711620145342D-1*FCT(X) DA12 580
X=.25098480972321280D1 DA12 590
Y=Y+.7489094100646149D-1*FCT(X) DA12 600
X=.12695899401039615D1 DA12 610
Y=Y+.25547924356911832D0*FCT(X) DA12 620
X=.45450668156378028D0 DA12 630
Y=Y+.57235907069288604D0*FCT(X) DA12 640
X=.50361889117293951D-1 DA12 650
Y=Y+.8538623277373985D0*FCT(X) DA12 660
RETURN DA12 670
END DA12 680