Merge branch '16-implement-analytic-inelastic-scattering-laws-for-draglibs-in-module-lib' into 'main'

Resolve "Implement analytic inelastic scattering laws for Draglibs in module LIB:"

See merge request dragon/5.1!29

1 files changed, 148 insertions, 0 deletions

diff --git a/Dragon/src/LIBECC.f b/Dragon/src/LIBECC.f
new file mode 100644
index 0000000..b0cea7d
--- /dev/null
+++ b/Dragon/src/LIBECC.f
@@ -0,0 +1,148 @@
+*DECK LIBECC
+      SUBROUTINE LIBECC(IPDRL,NGRO,IL,AWR,ENER,DELTA,DELECC,IGECCO,
+     > SCAT)
+*
+*-----------------------------------------------------------------------
+*
+*Purpose:
+* Construct the scattering matrix using analytical scattering kernels.
+*
+*Copyright:
+* Copyright (C) 2025 Ecole Polytechnique de Montreal
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU Lesser General Public
+* License as published by the Free Software Foundation; either
+* version 2.1 of the License, or (at your option) any later version
+*
+*Author(s): A. Hebert
+*
+*Parameters: input
+* IPDRL   pointer to the draglib (L_DRAGLIB signature).
+* NGRO    number of energy groups.
+* IL      Legendre order (=0: isotropic kernel in LAB).
+* AWR     mass ratio for current isotope.
+* ENER    energy limits of the coarse groups.
+* DELTA   lethargy widths of the coarse groups.
+* DELECC  lethargy widths of eccolib libraries.
+* IGECCO  number of equal-width lethargy groups with eccolib libraries.
+* IMPX    print flag.
+*
+*Parameters: output
+* SCAT    scattering matrix.
+*
+*-----------------------------------------------------------------------
+*
+      USE GANLIB
+*----
+*  SUBROUTINE ARGUMENTS
+*----
+      TYPE(C_PTR) IPDRL
+      INTEGER NGRO,IL,IGECCO
+      REAL AWR,ENER(NGRO+1),DELTA(NGRO),DELECC,SCAT(NGRO,NGRO)
+*----
+*  LOCAL VARIABLES
+*----
+      PARAMETER(MAXEDI=47,MAXTRA=10000)
+      CHARACTER CM*2
+      CHARACTER(LEN=8), SAVE, DIMENSION(MAXEDI) :: NAMEDI=
+     >  (/ 'NELAS   ','N2N     ','N3N     ','NNP     ','N4N     ',
+     >     'NINEL001','NINEL002','NINEL003','NINEL004','NINEL005',
+     >     'NINEL006','NINEL007','NINEL008','NINEL009','NINEL010',
+     >     'NINEL011','NINEL012','NINEL013','NINEL014','NINEL015',
+     >     'NINEL016','NINEL017','NINEL018','NINEL019','NINEL020',
+     >     'NINEL021','NINEL022','NINEL023','NINEL024','NINEL025',
+     >     'NINEL026','NINEL027','NINEL028','NINEL029','NINEL030',
+     >     'NINEL031','NINEL032','NINEL033','NINEL034','NINEL035',
+     >     'NINEL036','NINEL037','NINEL038','NINEL039','NINEL040',
+     >     'NINEL041','NINEL   '/)
+*----
+*  ALLOCATABLE ARRAYS
+*----
+      INTEGER, ALLOCATABLE, DIMENSION(:) :: NJJ,IJJ
+      REAL, ALLOCATABLE, DIMENSION(:) :: GAR,PRI,STIS,UUU,QQ
+      REAL, ALLOCATABLE, DIMENSION(:,:) :: SSS2
+      LOGICAL, ALLOCATABLE, DIMENSION(:) :: LPAR
+*----
+*  SCRATCH STORAGE ALLOCATION
+*----
+      ALLOCATE(NJJ(NGRO),IJJ(NGRO),GAR(NGRO*NGRO))
+      ALLOCATE(PRI(MAXTRA),STIS(NGRO),UUU(NGRO))
+      ALLOCATE(LPAR(MAXEDI),SSS2(NGRO,MAXEDI),QQ(MAXEDI))
+*----
+*  RECOVER CROSS SECTIONS CONTRIBUTING TO THE SCATTERING MATRIX
+*----
+      SSS2(:NGRO,:MAXEDI)=0.0
+      LPAR(:MAXEDI)=.FALSE.
+      QQ(:MAXEDI)=0.0
+      DO I=1,MAXEDI
+        CALL LCMLEN(IPDRL,NAMEDI(I),LENGT,ITYLCM)
+        IF(LENGT.GT.0) THEN
+          LPAR(I)=.TRUE.
+          CALL LCMGET(IPDRL,NAMEDI(I),SSS2(1,I))
+          DO IG1=1,NGRO
+            IF(NAMEDI(I).EQ.'N2N') THEN
+              SSS2(IG1,I)=2.0*SSS2(IG1,I)
+            ELSE IF(NAMEDI(I).EQ.'N3N') THEN
+              SSS2(IG1,I)=3.0*SSS2(IG1,I)
+            ELSE IF(NAMEDI(I).EQ.'N4N') THEN
+              SSS2(IG1,I)=4.0*SSS2(IG1,I)
+            ENDIF
+          ENDDO
+          DO IG1=NGRO,1,-1
+            IF(SSS2(IG1,I).NE.0.0) EXIT
+            QQ(I)=-ENER(IG1)
+          ENDDO
+        ENDIF
+      ENDDO
+*----
+*  CONSTRUCT THE SCATTERING MATRIX
+*----
+      WRITE (CM,'(I2.2)') IL
+      CALL LCMGET(IPDRL,'NJJS'//CM,NJJ)
+      CALL LCMGET(IPDRL,'IJJS'//CM,IJJ)
+      LENGT=0
+      DO IG1=1,NGRO
+        LENGT=LENGT+NJJ(IG1)
+      ENDDO
+      GAR(:LENGT)=0.0
+      CALL LCMGET(IPDRL,'SCAT'//CM,GAR)
+      UUU(1)=DELTA(1)
+      DO IG1=2,NGRO
+        UUU(IG1)=UUU(IG1-1)+DELTA(IG1)
+      ENDDO
+      IGAR=0
+      SCAT(:NGRO,:NGRO)=0.0
+      DO IG1=1,IGECCO
+        DO I=1,MAXEDI
+          IF(LPAR(I)) THEN
+            IF(NAMEDI(I).EQ.'NELAS') THEN
+              CALL LIBPRI(MAXTRA,DELECC,AWR,0,IL,NPRI,PRI)
+            ELSE
+              ! treshold reaction
+              IF(ENER(IG1).LE.-QQ(I)*(AWR+1.0)/AWR) CYCLE
+              CALL LIBPRQ(MAXTRA,DELECC,AWR,ENER(IG1),QQ(I),0,IL,
+     >        NPRI,PRI)
+            ENDIF
+            DO IPRI=1,NPRI
+              IG2=IG1+IPRI-1 ! IG2 <-- IG1
+              IF(IG2.GT.IGECCO) EXIT
+              SCAT(IG2,IG1)=SCAT(IG2,IG1)+PRI(IPRI)*SSS2(IG1,I)
+            ENDDO
+          ENDIF
+        ENDDO
+        IGAR=IGAR+NJJ(IG1)
+      ENDDO ! IG1
+      DO IG2=IGECCO+1,NGRO
+        DO IG1=IJJ(IG2),IJJ(IG2)-NJJ(IG2)+1,-1
+          IGAR=IGAR+1
+          SCAT(IG2,IG1)=GAR(IGAR)
+        ENDDO
+      ENDDO ! IG2
+*----
+*  SCRATCH STORAGE DEALLOCATION
+*----
+      DEALLOCATE(QQ,SSS2,LPAR)
+      DEALLOCATE(UUU,STIS,PRI)
+      DEALLOCATE(GAR,IJJ,NJJ)
+      RETURN
+      END