C QA3 10
C ..................................................................QA3 20
C QA3 30
C SUBROUTINE QA3 QA3 40
C QA3 50
C PURPOSE QA3 60
C TO COMPUTE INTEGRAL(EXP(-X)*FCT(X)/SQRT(X), SUMMED OVER X QA3 70
C FROM 0 TO INFINITY). QA3 80
C QA3 90
C USAGE QA3 100
C CALL QA3 (FCT,Y) QA3 110
C PARAMETER FCT REQUIRES AN EXTERNAL STATEMENT QA3 120
C QA3 130
C DESCRIPTION OF PARAMETERS QA3 140
C FCT - THE NAME OF AN EXTERNAL FUNCTION SUBPROGRAM USED. QA3 150
C Y - THE RESULTING INTEGRAL VALUE. QA3 160
C QA3 170
C REMARKS QA3 180
C NONE QA3 190
C QA3 200
C SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED QA3 210
C THE EXTERNAL FUNCTION SUBPROGRAM FCT(X) MUST BE FURNISHED QA3 220
C BY THE USER. QA3 230
C QA3 240
C METHOD QA3 250
C EVALUATION IS DONE BY MEANS OF 3-POINT GENERALIZED GAUSSIAN-QA3 260
C LAGUERRE QUADRATURE FORMULA, WHICH INTEGRATES EXACTLY, QA3 270
C WHENEVER FCT(X) IS A POLYNOMIAL UP TO DEGREE 5. QA3 280
C FOR REFERENCE, SEE QA3 290
C CONCUS/CASSATT/JAEHNIG/MELBY, TABLES FOR THE EVALUATION OF QA3 300
C INTEGRAL(X**BETA*EXP(-X)*F(X), SUMMED OVER X FROM 0 TO QA3 310
C INFINITY) BY GAUSS-LAGUERRE QUADRATURE, MTAC, VOL.17, QA3 320
C ISS.83 (1963), PP.245-256. QA3 330
C QA3 340
C ..................................................................QA3 350
C QA3 360
SUBROUTINE QA3(FCT,Y) QA3 370
C QA3 380
C QA3 390
X=5.525344 QA3 400
Y=.009060020*FCT(X) QA3 410
X=1.784493 QA3 420
Y=Y+.3141346*FCT(X) QA3 430
X=.1901635 QA3 440
Y=Y+1.449259*FCT(X) QA3 450
RETURN QA3 460
END QA3 470