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SUBROUTINE RSLMC

PURPOSE
   SOLUTION OF A SYSTEM OF LINEAR EQUATIONS AX=B

USAGE
   CALL RSLMC(A,AF,B,X,N,EPSI,IER,IA,V,PER)

DESCRIPTION OF PARAMETERS
   A	  INPUT MATRIX
   AF	  ARRAY OF THE FACTORIZATION OF THE ORIGINAL MATRIX
   B	  RIGHT HAND SIDE VECTOR
   X	  VECTOR CONTAINING THE SOLUTION ON RETURN
   N	  ORDER OF THE SYSTEM
   EPSI   RELATIVE PRECISION INDICATOR(REQUIRED INPUT)
   IER	  ERROR INDICATOR
	     =0 IF EACH COMPONENT OF X MEETS THE PRECISION EPSI
	     =1 IF ONLY THE NORM OF X MEETS THIS PRECISION
	     =2 IF THE PRECISION IN THE NORM OF THE COMPUTED
		SOLUTION IS LOWER THAN EPSI
	     =3 IF THE SOLUTION OBTAINED HAS NO MEANING AT ALL
	     =4 IF A DIAGONAL TERM OF THE UPPER TRIANGULAR
		FACTOR IS ZERO
   IA	  SIZE OF THE FIRST DIMENSION ASSIGNED TO THE ARRAY A
	  IN THE CALLING PROGRAM WHEN THE MATRIX IS IN DOUBLE
	  SUBSCRIPTED DATA STORAGE MODE.  IA=N WHEN THE MATRIX
	  IS IN SSP VECTOR STORAGE MODE.
   V	  WORKING STORAGE VECTOR
	  DIMENSION OF V MUST BE GREATER THAN OR EQUAL TO N
   PER	  VECTOR WHERE PERMUTATIONS OF ROWS OF THE MATRIX ARE
	  STORED
	  DIMENSION OF PER MUST BE GREATER THAN OR EQUAL TO N

REMARKS
   THE MATRIX OF THE SYSTEM MAY BE FACTORIZED BY THE SUBROUTINE
   FACTR IN THE ARRAY AF PRIOR TO ENTRY TO THIS SUBROUTINE.
   THE LOWER TRIANGULAR FACTOR MUST HAVE AN UNIT DIAGONAL.
   EPSI IS MODIFIED WHEN IER=2

SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED
   NONE

METHOD
   A TRIAL SOLUTION IS FIRST COMPUTED.	THEN CORRECTIONS ARE
   CALCULATED FROM RESIDUAL VECTORS.

REFERENCES
   J. H. WILKINSON - THE ALGEBRAIC EIGENVALUE PROBLEM -
   CLARENDON PRESS OXFORD, 1965.  H. J. BOWDLER, R. S. MARTIN,
   G. PETERS, AND J. H. WILKINSON.  'SOLUTION OF REAL AND
   COMPLEX SYSTEMS OF LINEAR EQUATIONS', NUMERISCHE MATHEMATIK,
   VOL. 8, NO. 3, 1966, 217-234.