Initial commit from Polytechnique Montreal

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diff --git a/Trivac/src/PNMAR2.f b/Trivac/src/PNMAR2.f
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+*DECK PNMAR2
+      FUNCTION PNMAR2(NGPT,L1,L2)
+*
+*-----------------------------------------------------------------------
+*
+*Purpose:
+* Return the dual Marshak boundary coefficients in plane geometry.
+* These coefficients are specific to the left boundary.
+*
+*Copyright:
+* Copyright (C) 2002 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
+* NGPT    number of Gauss-Legendre base points for the integration of
+*         the direction cosine. Set to 65 for exact integration.
+* L1      first Legendre order (even number in mixed dual cases).
+* L2      second Legendre order (odd number in mixed dual cases).
+
+*Parameters: output
+* PNMAR2  Marshak coefficient.
+*
+*-----------------------------------------------------------------------
+*
+*----
+*  SUBROUTINE ARGUMENTS
+*----
+      INTEGER NGPT,L1,L2
+      REAL PNMAR2
+*----
+*  LOCAL VARIABLES
+*----
+      PARAMETER(MAXGPT=64)
+      REAL ZGKSI(MAXGPT),WGKSI(MAXGPT)
+      DOUBLE PRECISION SUM,PNL1,PNL2,P1,P2
+*
+      IF(MOD(L1,2).EQ.0) THEN
+         CALL XABORT('PNMAR2: ODD FIRST INDEX EXPECTED.')
+      ENDIF
+      PNL1=0.0D0
+      PNL2=0.0D0
+      IF(NGPT.LE.64) THEN
+*        USE A GAUSS-LEGENDRE QUADRATURE.
+         CALL ALGPT(NGPT,-1.0,1.0,ZGKSI,WGKSI)
+         SUM=0.0
+         DO 30 I=NGPT/2+1,NGPT
+            P1=1.0D0
+            P2=ZGKSI(I)
+            IF(L1.EQ.0) THEN
+              PNL1=1.0D0
+            ELSE IF(L1.EQ.1) THEN
+              PNL1=P2
+            ELSE
+              DO 10 LL=2,L1
+              PNL1=(ZGKSI(I)*REAL(2*LL-1)*P2-REAL(LL-1)*P1)/REAL(LL)
+              P1=P2
+              P2=PNL1
+   10         CONTINUE
+            ENDIF
+            P1=1.0D0
+            P2=ZGKSI(I)
+            IF(L2.EQ.0) THEN
+              PNL2=1.0D0
+            ELSE IF(L2.EQ.1) THEN
+              PNL2=P2
+            ELSE
+              DO 20 LL=2,L2
+              PNL2=(ZGKSI(I)*REAL(2*LL-1)*P2-REAL(LL-1)*P1)/REAL(LL)
+              P1=P2
+              P2=PNL2
+   20         CONTINUE
+            ENDIF
+            SUM=SUM+WGKSI(I)*ZGKSI(I)*(PNL1*PNL2)
+   30    CONTINUE
+         PNMAR2=REAL(SUM*REAL(2*L1+1))
+      ELSE
+*        USE EXACT INTEGRATION.
+         NGPTE=16
+         CALL ALGPT(NGPTE,0.0,1.0,ZGKSI,WGKSI)
+         SUM=0.0D0
+         DO 60 I=1,NGPTE
+            P1=1.0D0
+            P2=ZGKSI(I)
+            IF(L1.EQ.0) THEN
+              PNL1=1.0D0
+            ELSE IF(L1.EQ.1) THEN
+              PNL1=P2
+            ELSE
+              DO 40 LL=2,L1
+              PNL1=(ZGKSI(I)*REAL(2*LL-1)*P2-REAL(LL-1)*P1)/REAL(LL)
+              P1=P2
+              P2=PNL1
+   40         CONTINUE
+            ENDIF
+            P1=1.0D0
+            P2=ZGKSI(I)
+            IF(L2.EQ.0) THEN
+              PNL2=1.0D0
+            ELSE IF(L2.EQ.1) THEN
+              PNL2=P2
+            ELSE
+              DO 50 LL=2,L2
+              PNL2=(ZGKSI(I)*REAL(2*LL-1)*P2-REAL(LL-1)*P1)/REAL(LL)
+              P1=P2
+              P2=PNL2
+   50         CONTINUE
+            ENDIF
+            SUM=SUM+WGKSI(I)*ZGKSI(I)*(PNL1*PNL2)
+   60    CONTINUE
+         PNMAR2=REAL(SUM*REAL(2*L1+1))
+      ENDIF
+      RETURN
+      END