[u/mrichter/AliRoot.git] / MINICERN / packlib / kernlib / kerngen / tcgen / trinv.F

*
* $Id$
*
* $Log$
* Revision 1.1.1.1  1996/02/15 17:49:54  mclareni
* Kernlib
*
*
#include "kerngen/pilot.h"
      SUBROUTINE TRINV (T,S,N)
C
C CERN PROGLIB# F112    TRINV           .VERSION KERNFOR  4.15  861204
C ORIG. 18/12/74 WH
C
#if defined(CERNLIB_INTDOUBL)
      DOUBLE PRECISION SUM, R
#endif
      DIMENSION T(*),S(*)
C
      MX = (N*N+N)/2
      IPIV = MX
C
      I = N
   10 R = 0.
      IF (T(IPIV).GT.0.)  R=1./T(IPIV)
      S(IPIV) = R
      NDSTEP = N
      IND = MX - N + I
C
   20 IF (IND.EQ.IPIV)        GO TO 50
      SUM = 0.
      IF (R.EQ.0.)            GO TO 40
      LHOR = IPIV
      LVER = IND
      J = I
C
   30 LHOR = LHOR + J
      LVER = LVER + 1
      SUM = SUM + T(LHOR)*S(LVER)
      J = J + 1
      IF (LHOR.LT.IND)        GO TO 30
C
   40 S(IND) = - SUM*R
      NDSTEP = NDSTEP - 1
      IND = IND - NDSTEP
        GO  TO                20
C
   50 IPIV = IPIV - I
      I = I - 1
      IF (I.GT.0)             GO TO 10
C
      RETURN
      END
Commit	Line	Data
fe4da5cc	1	*
	2	* $Id$
	3	*
	4	* $Log$
	5	* Revision 1.1.1.1 1996/02/15 17:49:54 mclareni
	6	* Kernlib
	7	*
	8	*
	9	#include "kerngen/pilot.h"
	10	SUBROUTINE TRINV (T,S,N)
	11	C
	12	C CERN PROGLIB# F112 TRINV .VERSION KERNFOR 4.15 861204
	13	C ORIG. 18/12/74 WH
	14	C
	15	#if defined(CERNLIB_INTDOUBL)
	16	DOUBLE PRECISION SUM, R
	17	#endif
	18	DIMENSION T(),S()
	19	C
	20	MX = (N*N+N)/2
	21	IPIV = MX
	22	C
	23	I = N
	24	10 R = 0.
	25	IF (T(IPIV).GT.0.) R=1./T(IPIV)
	26	S(IPIV) = R
	27	NDSTEP = N
	28	IND = MX - N + I
	29	C
	30	20 IF (IND.EQ.IPIV) GO TO 50
	31	SUM = 0.
	32	IF (R.EQ.0.) GO TO 40
	33	LHOR = IPIV
	34	LVER = IND
	35	J = I
	36	C
	37	30 LHOR = LHOR + J
	38	LVER = LVER + 1
	39	SUM = SUM + T(LHOR)*S(LVER)
	40	J = J + 1
	41	IF (LHOR.LT.IND) GO TO 30
	42	C
	43	40 S(IND) = - SUM*R
	44	NDSTEP = NDSTEP - 1
	45	IND = IND - NDSTEP
	46	GO TO 20
	47	C
	48	50 IPIV = IPIV - I
	49	I = I - 1
	50	IF (I.GT.0) GO TO 10
	51	C
	52	RETURN
	53	END