C SELFT3    SOURCE    CHAT      05/01/13    03:13:30     5004
      SUBROUTINE SELFT3(XGAUSS,NBNN,XE,QQ)
CCCCC
C     CALCUL DE LA SELF INDUCTANCE D'UN TRIANGLE
C     COPIE DE KALI1 DE CORFOU
CCCCC
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8(A-H,O-Z)

-INC PPARAM
-INC CCOPTIO
      REAL*8 XGAUSS(3)
      REAL*8 XE(3,NBNN)
      REAL*8 U(5),V(5),W(5)
*
      NDIM=IDIM
      NDIM2=IDIM-1
*
      U1=XGAUSS(1)
      V1=XGAUSS(2)
      W1=XGAUSS(3)
      DO 10 I=1,NBNN
        U(I)=XE(1,I)
        V(I)=XE(2,I)
        W(I)=XE(3,I)
   10 CONTINUE
      DO 11 I=1,2
        U(NBNN+I)=U(I)
        V(NBNN+I)=V(I)
        W(NBNN+I)=W(I)
   11 CONTINUE
*
      QQ=0.
      DO 20 J=1,3
        K1=J
        K2=J+1
        K3=J+2
        ALA=(U(K2)-U1)*(U(K3)-U(K2))+(V(K2)-V1)*(V(K3)-V(K2))
     &                              +(W(K2)-W1)*(W(K3)-W(K2))
        ALA=ALA/((U(K3)-U(K2))**2+(V(K3)-V(K2))**2+(W(K3)-W(K2))**2)
        XH=U(K2)-ALA*(U(K3)-U(K2))
        YH=V(K2)-ALA*(V(K3)-V(K2))
        ZH=W(K2)-ALA*(W(K3)-W(K2))
        T1=(V(K2)-V1)*(W(K3)-W1)-(V(K3)-V1)*(W(K2)-W1)
        T2=(W(K2)-W1)*(U(K3)-U1)-(W(K3)-W1)*(U(K2)-U1)
        T3=(U(K2)-U1)*(V(K3)-V1)-(U(K3)-U1)*(V(K2)-V1)
        R1=(YH-V1)*(W(K2)-W1)-(ZH-W1)*(V(K2)-V1)
        R2=(ZH-W1)*(U(K2)-U1)-(XH-U1)*(W(K2)-W1)
        R3=(XH-U1)*(V(K2)-V1)-(YH-V1)*(U(K2)-U1)
        PSCA=T1*R1+T2*R2+T3*R3
        THETA1=1.
        IF(PSCA.LT.0.) THETA1=-1.
        R1=(YH-V1)*(W(K3)-W1)-(ZH-W1)*(V(K3)-V1)
        R2=(ZH-W1)*(U(K3)-U1)-(XH-U1)*(W(K3)-W1)
        R3=(XH-U1)*(V(K3)-V1)-(YH-V1)*(U(K3)-U1)
        PSCA=T1*R1+T2*R2+T3*R3
        THETA2=1.
        IF(PSCA.LT.0.)THETA2=-1.
        PSCA=(XH-U1)*(U(K2)-U1)+(YH-V1)*(V(K2)-V1)+(ZH-W1)*(W(K2)-W1)
        D0=SQRT((XH-U1)**2+(YH-V1)**2+(ZH-W1)**2)
        D1=SQRT((U(K2)-U1)**2+(V(K2)-V1)**2+(W(K2)-W1)**2)
        COSTH1=PSCA/(D0*D1)
        THETA1=THETA1*ACOS(COSTH1)
        PSCA=(XH-U1)*(U(K3)-U1)+(YH-V1)*(V(K3)-V1)+(ZH-W1)*(W(K3)-W1)
        D2=SQRT((U(K3)-U1)**2+(V(K3)-V1)**2+(W(K3)-W1)**2)
        COSTH2=PSCA/(D0*D2)
        THETA2=THETA2*ACOS(COSTH2)
        ATA1=TAN(THETA1/2.)
        ATA2=TAN(THETA2/2.)
        ATA=((ATA2+1.)*(1.-ATA1))/((1.-ATA2)*(ATA1+1.))
        RATA=LOG(ATA)
        QQ=QQ+D0*RATA
  20  CONTINUE
      RETURN
      END