C QA4 10
C ..................................................................QA4 20
C QA4 30
C SUBROUTINE QA4 QA4 40
C QA4 50
C PURPOSE QA4 60
C TO COMPUTE INTEGRAL(EXP(-X)*FCT(X)/SQRT(X), SUMMED OVER X QA4 70
C FROM 0 TO INFINITY). QA4 80
C QA4 90
C USAGE QA4 100
C CALL QA4 (FCT,Y) QA4 110
C PARAMETER FCT REQUIRES AN EXTERNAL STATEMENT QA4 120
C QA4 130
C DESCRIPTION OF PARAMETERS QA4 140
C FCT - THE NAME OF AN EXTERNAL FUNCTION SUBPROGRAM USED. QA4 150
C Y - THE RESULTING INTEGRAL VALUE. QA4 160
C QA4 170
C REMARKS QA4 180
C NONE QA4 190
C QA4 200
C SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED QA4 210
C THE EXTERNAL FUNCTION SUBPROGRAM FCT(X) MUST BE FURNISHED QA4 220
C BY THE USER. QA4 230
C QA4 240
C METHOD QA4 250
C EVALUATION IS DONE BY MEANS OF 4-POINT GENERALIZED GAUSSIAN-QA4 260
C LAGUERRE QUADRATURE FORMULA, WHICH INTEGRATES EXACTLY, QA4 270
C WHENEVER FCT(X) IS A POLYNOMIAL UP TO DEGREE 7. QA4 280
C FOR REFERENCE, SEE QA4 290
C CONCUS/CASSATT/JAEHNIG/MELBY, TABLES FOR THE EVALUATION OF QA4 300
C INTEGRAL(X**BETA*EXP(-X)*F(X), SUMMED OVER X FROM 0 TO QA4 310
C INFINITY) BY GAUSS-LAGUERRE QUADRATURE, MTAC, VOL.17, QA4 320
C ISS.83 (1963), PP.245-256. QA4 330
C QA4 340
C ..................................................................QA4 350
C QA4 360
SUBROUTINE QA4(FCT,Y) QA4 370
C QA4 380
C QA4 390
X=8.588636 QA4 400
Y=.0003992081*FCT(X) QA4 410
X=3.926964 QA4 420
Y=Y+.03415597*FCT(X) QA4 430
X=1.339097 QA4 440
Y=Y+.4156047*FCT(X) QA4 450
X=.1453035 QA4 460
Y=Y+1.322294*FCT(X) QA4 470
RETURN QA4 480
END QA4 490