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s8gefs.F90
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!
! --- rename routines to prevent clashes with math libraries
!
SUBROUTINE S8GEFS(A,LDA,N,V,ITASK,IND,WORK,IWORK)
!***BEGIN PROLOGUE SGEFS
!***DATE WRITTEN 800317 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***CATEGORY NO. D2A1
!***KEYWORDS GENERAL SYSTEM OF LINEAR EQUATIONS,LINEAR EQUATIONS
!***AUTHOR VOORHEES, E., (LANL)
!***PURPOSE SGEFS solves a GENERAL single precision real
! NXN system of linear equations.
!***DESCRIPTION
!
! Subroutine SGEFS solves a general NxN system of single
! precision linear equations using LINPACK subroutines SGECO
! and SGESL. That is, if A is an NxN real matrix and if X
! and B are real N-vectors, then SGEFS solves the equation
!
! A*X=B.
!
! The matrix A is first factored into upper and lower tri-
! angular matrices U and L using partial pivoting. These
! factors and the pivoting information are used to find the
! solution vector X. An approximate condition number is
! calculated to provide a rough estimate of the number of
! digits of accuracy in the computed solution.
!
! If the equation A*X=B is to be solved for more than one vector
! B, the factoring of A does not need to be performed again and
! the option to only solve (ITASK .GT. 1) will be faster for
! the succeeding solutions. In this case, the contents of A,
! LDA, N and IWORK must not have been altered by the user follow-
! ing factorization (ITASK=1). IND will not be changed by SGEFS
! in this case.
!
! Argument Description ***
!
! A REAL(LDA,N)
! on entry, the doubly subscripted array with dimension
! (LDA,N) which contains the coefficient matrix.
! on return, an upper triangular matrix U and the
! multipliers necessary to construct a matrix L
! so that A=L*U.
! LDA INTEGER
! the leading dimension of the array A. LDA must be great-
! er than or equal to N. (terminal error message IND=-1)
! N INTEGER
! the order of the matrix A. The first N elements of
! the array A are the elements of the first column of
! the matrix A. N must be greater than or equal to 1.
! (terminal error message IND=-2)
! V REAL(N)
! on entry, the singly subscripted array(vector) of di-
! mension N which contains the right hand side B of a
! system of simultaneous linear equations A*X=B.
! on return, V contains the solution vector, X .
! ITASK INTEGER
! If ITASK=1, the matrix A is factored and then the
! linear equation is solved.
! If ITASK .GT. 1, the equation is solved using the existing
! factored matrix A and IWORK.
! If ITASK .LT. 1, then terminal error message IND=-3 is
! printed.
! IND INTEGER
! GT. 0 IND is a rough estimate of the number of digits
! of accuracy in the solution, X.
! NOT DONE IN THIS VERSION.
! LT. 0 see error message corresponding to IND below.
! WORK REAL(N)
! a singly subscripted array of dimension at least N.
! IWORK INTEGER(N)
! a singly subscripted array of dimension at least N.
!
! Error Messages Printed ***
!
! IND=-1 terminal N is greater than LDA.
! IND=-2 terminal N is less than 1.
! IND=-3 terminal ITASK is less than 1.
! IND=-4 terminal The matrix A is computationally singular.
! A solution has not been computed.
! IND=-10 warning The solution has no apparent significance.
! The solution may be inaccurate or the matrix
! A may be poorly scaled.
!
! Note- The above terminal(*fatal*) error messages are
! designed to be handled by XERRWV in which
! LEVEL=1 (recoverable) and IFLAG=2 . LEVEL=0
! for warning error messages from XERROR. Unless
! the user provides otherwise, an error message
! will be printed followed by an abort.
!***REFERENCES SUBROUTINE SGEFS WAS DEVELOPED BY GROUP C-3, LOS ALAMOS
! SCIENTIFIC LABORATORY, LOS ALAMOS, NM 87545.
! THE LINPACK SUBROUTINES USED BY SGEFS ARE DESCRIBED IN
! DETAIL IN THE *LINPACK USERS GUIDE* PUBLISHED BY
! THE SOCIETY FOR INDUSTRIAL AND APPLIED MATHEMATICS
! (SIAM) DATED 1979.
!***ROUTINES CALLED SGECO,SGESL,XERROR,XERRWV
!***END PROLOGUE SGEFS
!
INTEGER LDA,N,ITASK,IND,IWORK(N)
REAL A(LDA,N),V(N),WORK(N)
REAL RCOND
!***FIRST EXECUTABLE STATEMENT SGEFS
IF (LDA.LT.N) GO TO 101
IF (N.LE.0) GO TO 102
IF (ITASK.LT.1) GO TO 103
IF (ITASK.GT.1) GO TO 20
!
! FACTOR MATRIX A INTO LU
CALL S8GECO(A,LDA,N,IWORK,RCOND,WORK)
!
! CHECK FOR COMPUTATIONALLY SINGULAR MATRIX
IF (RCOND.EQ.0.0) GO TO 104
!
! COMPUTE IND (ESTIMATE OF NO. OF SIGNIFICANT DIGITS)
! NOT DONE IN THIS VERSION, RETURN 0 INSTEAD
IND=0
!
! SOLVE AFTER FACTORING
20 CALL S8GESL(A,LDA,N,IWORK,V,0)
RETURN
!
! IF LDA.LT.N, IND=-1, TERMINAL XERRWV MESSAGE
101 IND=-1
CALL X8ERRWV( 'SGEFS ERROR (IND=-1) -- LDA=I1 IS LESS THAN N=I2', &
48,-1,1,2,LDA,N,0,0.0,0.0)
RETURN
!
! IF N.LT.1, IND=-2, TERMINAL XERRWV MESSAGE
102 IND=-2
CALL X8ERRWV( 'SGEFS ERROR (IND=-2) -- N=I1 IS LESS THAN 1', &
43,-2,1,1,N,0,0,0.0,0.0)
RETURN
!
! IF ITASK.LT.1, IND=-3, TERMINAL XERRWV MESSAGE
103 IND=-3
CALL X8ERRWV( 'SGEFS ERROR (IND=-3) -- ITASK=I1 IS LESS THAN 1', &
47,-3,1,1,ITASK,0,0,0.0,0.0)
RETURN
!
! IF SINGULAR MATRIX, IND=-4, TERMINAL XERRWV MESSAGE
104 IND=-4
CALL X8ERRWV( 'SGEFS ERROR (IND=-4) -- SINGULAR MATRIX A - NO SOLUT &
&ION',55,-4,1,0,0,0,0,0.0,0.0)
RETURN
!
END
SUBROUTINE S8GECO(A,LDA,N,IPVT,RCOND,Z)
!***BEGIN PROLOGUE SGECO
!***DATE WRITTEN 780814 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***REVISION HISTORY (YYMMDD)
! 000330 Modified array declarations. (JEC)
!***CATEGORY NO. D2A1
!***KEYWORDS CONDITION,FACTOR,LINEAR ALGEBRA,LINPACK,MATRIX
!***AUTHOR MOLER, C. B., (U. OF NEW MEXICO)
!***PURPOSE Factors a real matrix by Gaussian elimination and estimates
! the condition number of the matrix.
!***DESCRIPTION
!
! SGECO factors a real matrix by Gaussian elimination
! and estimates the condition of the matrix.
!
! If RCOND is not needed, SGEFA is slightly faster.
! To solve A*X = B , follow SGECO by SGESL.
! To compute INVERSE(A)*C , follow SGECO by SGESL.
! To compute DETERMINANT(A) , follow SGECO by SGEDI.
! To compute INVERSE(A) , follow SGECO by SGEDI.
!
! On Entry
!
! A REAL(LDA, N)
! the matrix to be factored.
!
! LDA INTEGER
! the leading dimension of the array A .
!
! N INTEGER
! the order of the matrix A .
!
! On Return
!
! A an upper triangular matrix and the multipliers
! which were used to obtain it.
! The factorization can be written A = L*U , where
! L is a product of permutation and unit lower
! triangular matrices and U is upper triangular.
!
! IPVT INTEGER(N)
! an integer vector of pivot indices.
!
! RCOND REAL
! an estimate of the reciprocal condition of A .
! For the system A*X = B , relative perturbations
! in A and B of size EPSILON may cause
! relative perturbations in X of size EPSILON/RCOND .
! If RCOND is so small that the logical expression
! 1.0 + RCOND .EQ. 1.0
! is true, then A may be singular to working
! precision. In particular, RCOND is zero if
! exact singularity is detected or the estimate
! underflows.
!
! Z REAL(N)
! a work vector whose contents are usually unimportant.
! If A is close to a singular matrix, then Z is
! an approximate null vector in the sense that
! NORM(A*Z) = RCOND*NORM(A)*NORM(Z) .
!
! LINPACK. This version dated 08/14/78 .
! Cleve Moler, University of New Mexico, Argonne National Lab.
!
! Subroutines and Functions
!
! LINPACK SGEFA
! BLAS S8AXPY,S8DOT,S8SCAL,S8ASUM
! Fortran ABS,AMAX1,SIGN
!***REFERENCES DONGARRA J.J., BUNCH J.R., MOLER C.B., STEWART G.W.,
! *LINPACK USERS GUIDE*, SIAM, 1979.
!***ROUTINES CALLED S8ASUM,S8AXPY,S8DOT,SGEFA,S8SCAL
!***END PROLOGUE SGECO
INTEGER LDA,N,IPVT(*)
REAL A(LDA,*),Z(*)
REAL RCOND
!
REAL S8DOT,EK,T,WK,WKM
REAL ANORM,S,S8ASUM,SM,YNORM
INTEGER INFO,J,K,KB,KP1,L
!
! COMPUTE 1-NORM OF A
!
!***FIRST EXECUTABLE STATEMENT SGECO
ANORM = 0.0E0
DO 10 J = 1, N
ANORM = AMAX1(ANORM,S8ASUM(N,A(1,J),1))
10 CONTINUE
!
! FACTOR
!
CALL S8GEFA(A,LDA,N,IPVT,INFO)
!
! RCOND = 1/(NORM(A)*(ESTIMATE OF NORM(INVERSE(A)))) .
! ESTIMATE = NORM(Z)/NORM(Y) WHERE A*Z = Y AND TRANS(A)*Y = E .
! TRANS(A) IS THE TRANSPOSE OF A . THE COMPONENTS OF E ARE
! CHOSEN TO CAUSE MAXIMUM LOCAL GROWTH IN THE ELEMENTS OF W WHERE
! TRANS(U)*W = E . THE VECTORS ARE FREQUENTLY RESCALED TO AVOID
! OVERFLOW.
!
! SOLVE TRANS(U)*W = E
!
EK = 1.0E0
DO 20 J = 1, N
Z(J) = 0.0E0
20 CONTINUE
DO 100 K = 1, N
IF (Z(K) .NE. 0.0E0) EK = SIGN(EK,-Z(K))
IF (ABS(EK-Z(K)) .LE. ABS(A(K,K))) GO TO 30
S = ABS(A(K,K))/ABS(EK-Z(K))
CALL S8SCAL(N,S,Z,1)
EK = S*EK
30 CONTINUE
WK = EK - Z(K)
WKM = -EK - Z(K)
S = ABS(WK)
SM = ABS(WKM)
IF (A(K,K) .EQ. 0.0E0) GO TO 40
WK = WK/A(K,K)
WKM = WKM/A(K,K)
GO TO 50
40 CONTINUE
WK = 1.0E0
WKM = 1.0E0
50 CONTINUE
KP1 = K + 1
IF (KP1 .GT. N) GO TO 90
DO 60 J = KP1, N
SM = SM + ABS(Z(J)+WKM*A(K,J))
Z(J) = Z(J) + WK*A(K,J)
S = S + ABS(Z(J))
60 CONTINUE
IF (S .GE. SM) GO TO 80
T = WKM - WK
WK = WKM
DO 70 J = KP1, N
Z(J) = Z(J) + T*A(K,J)
70 CONTINUE
80 CONTINUE
90 CONTINUE
Z(K) = WK
100 CONTINUE
S = 1.0E0/S8ASUM(N,Z,1)
CALL S8SCAL(N,S,Z,1)
!
! SOLVE TRANS(L)*Y = W
!
DO 120 KB = 1, N
K = N + 1 - KB
IF (K .LT. N) Z(K) = Z(K) + S8DOT(N-K,A(K+1,K),1,Z(K+1),1)
IF (ABS(Z(K)) .LE. 1.0E0) GO TO 110
S = 1.0E0/ABS(Z(K))
CALL S8SCAL(N,S,Z,1)
110 CONTINUE
L = IPVT(K)
T = Z(L)
Z(L) = Z(K)
Z(K) = T
120 CONTINUE
S = 1.0E0/S8ASUM(N,Z,1)
CALL S8SCAL(N,S,Z,1)
!
YNORM = 1.0E0
!
! SOLVE L*V = Y
!
DO 140 K = 1, N
L = IPVT(K)
T = Z(L)
Z(L) = Z(K)
Z(K) = T
IF (K .LT. N) CALL S8AXPY(N-K,T,A(K+1,K),1,Z(K+1),1)
IF (ABS(Z(K)) .LE. 1.0E0) GO TO 130
S = 1.0E0/ABS(Z(K))
CALL S8SCAL(N,S,Z,1)
YNORM = S*YNORM
130 CONTINUE
140 CONTINUE
S = 1.0E0/S8ASUM(N,Z,1)
CALL S8SCAL(N,S,Z,1)
YNORM = S*YNORM
!
! SOLVE U*Z = V
!
DO 160 KB = 1, N
K = N + 1 - KB
IF (ABS(Z(K)) .LE. ABS(A(K,K))) GO TO 150
S = ABS(A(K,K))/ABS(Z(K))
CALL S8SCAL(N,S,Z,1)
YNORM = S*YNORM
150 CONTINUE
IF (A(K,K) .NE. 0.0E0) Z(K) = Z(K)/A(K,K)
IF (A(K,K) .EQ. 0.0E0) Z(K) = 1.0E0
T = -Z(K)
CALL S8AXPY(K-1,T,A(1,K),1,Z(1),1)
160 CONTINUE
! MAKE ZNORM = 1.0
S = 1.0E0/S8ASUM(N,Z,1)
CALL S8SCAL(N,S,Z,1)
YNORM = S*YNORM
!
IF (ANORM .NE. 0.0E0) RCOND = YNORM/ANORM
IF (ANORM .EQ. 0.0E0) RCOND = 0.0E0
RETURN
END
SUBROUTINE S8GEFA(A,LDA,N,IPVT,INFO)
!***BEGIN PROLOGUE SGEFA
!***DATE WRITTEN 780814 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***REVISION HISTORY (YYMMDD)
! 000330 Modified array declarations. (JEC)
!***CATEGORY NO. D2A1
!***KEYWORDS FACTOR,LINEAR ALGEBRA,LINPACK,MATRIX
!***AUTHOR MOLER, C. B., (U. OF NEW MEXICO)
!***PURPOSE Factors a real matrix by Gaussian elimination.
!***DESCRIPTION
!
! SGEFA factors a real matrix by Gaussian elimination.
!
! SGEFA is usually called by SGECO, but it can be called
! directly with a saving in time if RCOND is not needed.
! (Time for SGECO) = (1 + 9/N)*(Time for SGEFA) .
!
! On Entry
!
! A REAL(LDA, N)
! the matrix to be factored.
!
! LDA INTEGER
! the leading dimension of the array A .
!
! N INTEGER
! the order of the matrix A .
!
! On Return
!
! A an upper triangular matrix and the multipliers
! which were used to obtain it.
! The factorization can be written A = L*U , where
! L is a product of permutation and unit lower
! triangular matrices and U is upper triangular.
!
! IPVT INTEGER(N)
! an integer vector of pivot indices.
!
! INFO INTEGER
! = 0 normal value.
! = K if U(K,K) .EQ. 0.0 . This is not an error
! condition for this subroutine, but it does
! indicate that SGESL or SGEDI will divide by zero
! if called. Use RCOND in SGECO for a reliable
! indication of singularity.
!
! LINPACK. This version dated 08/14/78 .
! Cleve Moler, University of New Mexico, Argonne National Lab.
!
! Subroutines and Functions
!
! BLAS S8AXPY,S8SCAL,IS8AMAX
!***REFERENCES DONGARRA J.J., BUNCH J.R., MOLER C.B., STEWART G.W.,
! *LINPACK USERS GUIDE*, SIAM, 1979.
!***ROUTINES CALLED IS8AMAX,S8AXPY,S8SCAL
!***END PROLOGUE SGEFA
INTEGER LDA,N,IPVT(*),INFO
REAL A(LDA,*)
!
REAL T
INTEGER IS8AMAX,J,K,KP1,L,NM1
!
! GAUSSIAN ELIMINATION WITH PARTIAL PIVOTING
!
!***FIRST EXECUTABLE STATEMENT SGEFA
INFO = 0
NM1 = N - 1
IF (NM1 .LT. 1) GO TO 70
DO 60 K = 1, NM1
KP1 = K + 1
!
! FIND L = PIVOT INDEX
!
L = IS8AMAX(N-K+1,A(K,K),1) + K - 1
IPVT(K) = L
!
! ZERO PIVOT IMPLIES THIS COLUMN ALREADY TRIANGULARIZED
!
IF (A(L,K) .EQ. 0.0E0) GO TO 40
!
! INTERCHANGE IF NECESSARY
!
IF (L .EQ. K) GO TO 10
T = A(L,K)
A(L,K) = A(K,K)
A(K,K) = T
10 CONTINUE
!
! COMPUTE MULTIPLIERS
!
T = -1.0E0/A(K,K)
CALL S8SCAL(N-K,T,A(K+1,K),1)
!
! ROW ELIMINATION WITH COLUMN INDEXING
!
DO 30 J = KP1, N
T = A(L,J)
IF (L .EQ. K) GO TO 20
A(L,J) = A(K,J)
A(K,J) = T
20 CONTINUE
CALL S8AXPY(N-K,T,A(K+1,K),1,A(K+1,J),1)
30 CONTINUE
GO TO 50
40 CONTINUE
INFO = K
50 CONTINUE
60 CONTINUE
70 CONTINUE
IPVT(N) = N
IF (A(N,N) .EQ. 0.0E0) INFO = N
RETURN
END
SUBROUTINE S8GESL(A,LDA,N,IPVT,B,JOB)
!***BEGIN PROLOGUE SGESL
!***DATE WRITTEN 780814 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***REVISION HISTORY (YYMMDD)
! 000330 Modified array declarations. (JEC)
!***CATEGORY NO. D2A1
!***KEYWORDS LINEAR ALGEBRA,LINPACK,MATRIX,SOLVE
!***AUTHOR MOLER, C. B., (U. OF NEW MEXICO)
!***PURPOSE Solves the real system A*X=B or TRANS(A)*X=B
! using the factors of SGECO or SGEFA
!***DESCRIPTION
!
! SGESL solves the real system
! A * X = B or TRANS(A) * X = B
! using the factors computed by SGECO or SGEFA.
!
! On Entry
!
! A REAL(LDA, N)
! the output from SGECO or SGEFA.
!
! LDA INTEGER
! the leading dimension of the array A .
!
! N INTEGER
! the order of the matrix A .
!
! IPVT INTEGER(N)
! the pivot vector from SGECO or SGEFA.
!
! B REAL(N)
! the right hand side vector.
!
! JOB INTEGER
! = 0 to solve A*X = B ,
! = nonzero to solve TRANS(A)*X = B where
! TRANS(A) is the transpose.
!
! On Return
!
! B the solution vector X .
!
! Error Condition
!
! A division by zero will occur if the input factor contains a
! zero on the diagonal. Technically, this indicates singularity,
! but it is often caused by improper arguments or improper
! setting of LDA . It will not occur if the subroutines are
! called correctly and if SGECO has set RCOND .GT. 0.0
! or SGEFA has set INFO .EQ. 0 .
!
! To compute INVERSE(A) * C where C is a matrix
! with P columns
! CALL SGECO(A,LDA,N,IPVT,RCOND,Z)
! IF (RCOND is too small) GO TO ...
! DO 10 J = 1, P
! CALL SGESL(A,LDA,N,IPVT,C(1,J),0)
! 10 CONTINUE
!
! LINPACK. This version dated 08/14/78 .
! Cleve Moler, University of New Mexico, Argonne National Lab.
!
! Subroutines and Functions
!
! BLAS S8AXPY,S8DOT
!***REFERENCES DONGARRA J.J., BUNCH J.R., MOLER C.B., STEWART G.W.,
! *LINPACK USERS GUIDE*, SIAM, 1979.
!***ROUTINES CALLED S8AXPY,S8DOT
!***END PROLOGUE SGESL
INTEGER LDA,N,IPVT(*),JOB
REAL A(LDA,*),B(*)
!
REAL S8DOT,T
INTEGER K,KB,L,NM1
!***FIRST EXECUTABLE STATEMENT SGESL
NM1 = N - 1
IF (JOB .NE. 0) GO TO 50
!
! JOB = 0 , SOLVE A * X = B
! FIRST SOLVE L*Y = B
!
IF (NM1 .LT. 1) GO TO 30
DO 20 K = 1, NM1
L = IPVT(K)
T = B(L)
IF (L .EQ. K) GO TO 10
B(L) = B(K)
B(K) = T
10 CONTINUE
CALL S8AXPY(N-K,T,A(K+1,K),1,B(K+1),1)
20 CONTINUE
30 CONTINUE
!
! NOW SOLVE U*X = Y
!
DO 40 KB = 1, N
K = N + 1 - KB
B(K) = B(K)/A(K,K)
T = -B(K)
CALL S8AXPY(K-1,T,A(1,K),1,B(1),1)
40 CONTINUE
GO TO 100
50 CONTINUE
!
! JOB = NONZERO, SOLVE TRANS(A) * X = B
! FIRST SOLVE TRANS(U)*Y = B
!
DO 60 K = 1, N
T = S8DOT(K-1,A(1,K),1,B(1),1)
B(K) = (B(K) - T)/A(K,K)
60 CONTINUE
!
! NOW SOLVE TRANS(L)*X = Y
!
IF (NM1 .LT. 1) GO TO 90
DO 80 KB = 1, NM1
K = N - KB
B(K) = B(K) + S8DOT(N-K,A(K+1,K),1,B(K+1),1)
L = IPVT(K)
IF (L .EQ. K) GO TO 70
T = B(L)
B(L) = B(K)
B(K) = T
70 CONTINUE
80 CONTINUE
90 CONTINUE
100 CONTINUE
RETURN
END
SUBROUTINE X8ERROR(MESSG,NMESSG,NERR,LEVEL)
!***BEGIN PROLOGUE XERROR
!***DATE WRITTEN 790801 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***CATEGORY NO. R3C
!***KEYWORDS ERROR,XERROR PACKAGE
!***AUTHOR JONES, R. E., (SNLA)
!***PURPOSE Processes an error (diagnostic) message.
!***DESCRIPTION
! Abstract
! XERROR processes a diagnostic message, in a manner
! determined by the value of LEVEL and the current value
! of the library error control flag, KONTRL.
! (See subroutine XSETF for details.)
!
! Description of Parameters
! --Input--
! MESSG - the Hollerith message to be processed, containing
! no more than 72 characters.
! NMESSG- the actual number of characters in MESSG.
! NERR - the error number associated with this message.
! NERR must not be zero.
! LEVEL - error category.
! =2 means this is an unconditionally fatal error.
! =1 means this is a recoverable error. (I.e., it is
! non-fatal if XSETF has been appropriately called.)
! =0 means this is a warning message only.
! =-1 means this is a warning message which is to be
! printed at most once, regardless of how many
! times this call is executed.
!
! Examples
! CALL XERROR('SMOOTH -- NUM WAS ZERO.',23,1,2)
! CALL XERROR('INTEG -- LESS THAN FULL ACCURACY ACHIEVED.',
! 43,2,1)
! CALL XERROR('ROOTER -- ACTUAL ZERO OF F FOUND BEFORE INTERVAL F
! 1ULLY COLLAPSED.',65,3,0)
! CALL XERROR('EXP -- UNDERFLOWS BEING SET TO ZERO.',39,1,-1)
!
! Latest revision --- 19 MAR 1980
! Written by Ron Jones, with SLATEC Common Math Library Subcommittee
!***REFERENCES JONES R.E., KAHANER D.K., "XERROR, THE SLATEC ERROR-
! HANDLING PACKAGE", SAND82-0800, SANDIA LABORATORIES,
! 1982.
!***ROUTINES CALLED XERRWV
!***END PROLOGUE XERROR
CHARACTER*(*) MESSG
!***FIRST EXECUTABLE STATEMENT XERROR
CALL X8ERRWV(MESSG,NMESSG,NERR,LEVEL,0,0,0,0,0.,0.)
RETURN
END
SUBROUTINE X8ERRWV(MESSG,NMESSG,NERR,LEVEL,NI,I1,I2,NR,R1,R2)
!***BEGIN PROLOGUE XERRWV
!***DATE WRITTEN 800319 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***CATEGORY NO. R3C
!***KEYWORDS ERROR,XERROR PACKAGE
!***AUTHOR JONES, R. E., (SNLA)
!***PURPOSE Processes error message allowing 2 integer and two real
! values to be included in the message.
!***DESCRIPTION
! Abstract
! XERRWV processes a diagnostic message, in a manner
! determined by the value of LEVEL and the current value
! of the library error control flag, KONTRL.
! (See subroutine XSETF for details.)
! In addition, up to two integer values and two real
! values may be printed along with the message.
!
! Description of Parameters
! --Input--
! MESSG - the Hollerith message to be processed.
! NMESSG- the actual number of characters in MESSG.
! NERR - the error number associated with this message.
! NERR must not be zero.
! LEVEL - error category.
! =2 means this is an unconditionally fatal error.
! =1 means this is a recoverable error. (I.e., it is
! non-fatal if XSETF has been appropriately called.)
! =0 means this is a warning message only.
! =-1 means this is a warning message which is to be
! printed at most once, regardless of how many
! times this call is executed.
! NI - number of integer values to be printed. (0 to 2)
! I1 - first integer value.
! I2 - second integer value.
! NR - number of real values to be printed. (0 to 2)
! R1 - first real value.
! R2 - second real value.
!
! Examples
! CALL X8ERRWV('SMOOTH -- NUM (=I1) WAS ZERO.',29,1,2,
! 1 1,NUM,0,0,0.,0.)
! CALL XERRWV('QUADXY -- REQUESTED ERROR (R1) LESS THAN MINIMUM (
! 1R2).,54,77,1,0,0,0,2,ERRREQ,ERRMIN)
!
! Latest revision --- 19 MAR 1980
! Written by Ron Jones, with SLATEC Common Math Library Subcommittee
!***REFERENCES JONES R.E., KAHANER D.K., "XERROR, THE SLATEC ERROR-
! HANDLING PACKAGE", SAND82-0800, SANDIA LABORATORIES,
! 1982.
!***ROUTINES CALLED F8DUMP,I8MACH,J84SAVE,XERABT,XERCTL,XERPRT,XERSAV,
! XGETUA
!***END PROLOGUE XERRWV
CHARACTER*(*) MESSG
CHARACTER*20 LFIRST
CHARACTER*37 FORM
DIMENSION LUN(5)
! GET FLAGS
!***FIRST EXECUTABLE STATEMENT XERRWV
LKNTRL = J84SAVE(2,0,.FALSE.)
MAXMES = J84SAVE(4,0,.FALSE.)
! CHECK FOR VALID INPUT
IF ((NMESSG.GT.0).AND.(NERR.NE.0).AND. &
(LEVEL.GE.(-1)).AND.(LEVEL.LE.2)) GO TO 10
IF (LKNTRL.GT.0) CALL X8ERPRT('FATAL ERROR IN...',17)
CALL X8ERPRT('XERROR -- INVALID INPUT',23)
IF (LKNTRL.GT.0) CALL F8DUMP
IF (LKNTRL.GT.0) CALL X8ERPRT('JOB ABORT DUE TO FATAL ERROR.', &
29)
IF (LKNTRL.GT.0) CALL X8ERSAV(' ',0,0,0,KDUMMY)
CALL X8ERABT('XERROR -- INVALID INPUT',23)
RETURN
10 CONTINUE
! RECORD MESSAGE
JUNK = J84SAVE(1,NERR,.TRUE.)
CALL X8ERSAV(MESSG,NMESSG,NERR,LEVEL,KOUNT)
! LET USER OVERRIDE
LFIRST = MESSG
LMESSG = NMESSG
LERR = NERR
LLEVEL = LEVEL
CALL X8ERCTL(LFIRST,LMESSG,LERR,LLEVEL,LKNTRL)
! RESET TO ORIGINAL VALUES
LMESSG = NMESSG
LERR = NERR
LLEVEL = LEVEL
LKNTRL = MAX0(-2,MIN0(2,LKNTRL))
MKNTRL = IABS(LKNTRL)
! DECIDE WHETHER TO PRINT MESSAGE
IF ((LLEVEL.LT.2).AND.(LKNTRL.EQ.0)) GO TO 100
IF (((LLEVEL.EQ.(-1)).AND.(KOUNT.GT.MIN0(1,MAXMES))) &
.OR.((LLEVEL.EQ.0) .AND.(KOUNT.GT.MAXMES)) &
.OR.((LLEVEL.EQ.1) .AND.(KOUNT.GT.MAXMES).AND.(MKNTRL.EQ.1)) &
.OR.((LLEVEL.EQ.2) .AND.(KOUNT.GT.MAX0(1,MAXMES)))) GO TO 100
IF (LKNTRL.LE.0) GO TO 20
CALL X8ERPRT(' ',1)
! INTRODUCTION
IF (LLEVEL.EQ.(-1)) CALL X8ERPRT &
('WARNING MESSAGE...THIS MESSAGE WILL ONLY BE PRINTED ONCE.',57)
IF (LLEVEL.EQ.0) CALL X8ERPRT('WARNING IN...',13)
IF (LLEVEL.EQ.1) CALL X8ERPRT &
('RECOVERABLE ERROR IN...',23)
IF (LLEVEL.EQ.2) CALL X8ERPRT('FATAL ERROR IN...',17)
20 CONTINUE
! MESSAGE
CALL X8ERPRT(MESSG,LMESSG)
CALL X8GETUA(LUN,NUNIT)
ISIZEI = LOG10(REAL(I8MACH(9))) + 1.0
ISIZEF = LOG10(REAL(I8MACH(10))**I8MACH(11)) + 1.0
DO 50 KUNIT=1,NUNIT
IUNIT = LUN(KUNIT)
IF (IUNIT.EQ.0) IUNIT = I8MACH(4)
DO 22 I=1,MIN(NI,2)
WRITE (FORM,21) I,ISIZEI
21 FORMAT ('(11X,21HIN ABOVE MESSAGE, I',I1,'=,I',I2,') ')
IF (I.EQ.1) WRITE (IUNIT,FORM) I1
IF (I.EQ.2) WRITE (IUNIT,FORM) I2
22 CONTINUE
DO 24 I=1,MIN(NR,2)
WRITE (FORM,23) I,ISIZEF+10,ISIZEF
23 FORMAT ('(11X,21HIN ABOVE MESSAGE, R',I1,'=,E', &
I2,'.',I2,')')
IF (I.EQ.1) WRITE (IUNIT,FORM) R1
IF (I.EQ.2) WRITE (IUNIT,FORM) R2
24 CONTINUE
IF (LKNTRL.LE.0) GO TO 40
! ERROR NUMBER
WRITE (IUNIT,30) LERR
30 FORMAT (15H ERROR NUMBER =,I10)
40 CONTINUE
50 CONTINUE
! TRACE-BACK
IF (LKNTRL.GT.0) CALL F8DUMP
100 CONTINUE
IFATAL = 0
IF ((LLEVEL.EQ.2).OR.((LLEVEL.EQ.1).AND.(MKNTRL.EQ.2))) &
IFATAL = 1
! QUIT HERE IF MESSAGE IS NOT FATAL
IF (IFATAL.LE.0) RETURN
IF ((LKNTRL.LE.0).OR.(KOUNT.GT.MAX0(1,MAXMES))) GO TO 120
! PRINT REASON FOR ABORT
IF (LLEVEL.EQ.1) CALL X8ERPRT &
('JOB ABORT DUE TO UNRECOVERED ERROR.',35)
IF (LLEVEL.EQ.2) CALL X8ERPRT &
('JOB ABORT DUE TO FATAL ERROR.',29)
! PRINT ERROR SUMMARY
CALL X8ERSAV(' ',-1,0,0,KDUMMY)
120 CONTINUE
! ABORT
IF ((LLEVEL.EQ.2).AND.(KOUNT.GT.MAX0(1,MAXMES))) LMESSG = 0
CALL X8ERABT(MESSG,LMESSG)
RETURN
END
SUBROUTINE X8ERSAV(MESSG,NMESSG,NERR,LEVEL,ICOUNT)
!***BEGIN PROLOGUE XERSAV
!***DATE WRITTEN 800319 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***CATEGORY NO. Z
!***KEYWORDS ERROR,XERROR PACKAGE
!***AUTHOR JONES, R. E., (SNLA)
!***PURPOSE Records that an error occurred.
!***DESCRIPTION
! Abstract
! Record that this error occurred.
!
! Description of Parameters
! --Input--
! MESSG, NMESSG, NERR, LEVEL are as in XERROR,
! except that when NMESSG=0 the tables will be
! dumped and cleared, and when NMESSG is less than zero the
! tables will be dumped and not cleared.
! --Output--
! ICOUNT will be the number of times this message has
! been seen, or zero if the table has overflowed and
! does not contain this message specifically.
! When NMESSG=0, ICOUNT will not be altered.
!
! Written by Ron Jones, with SLATEC Common Math Library Subcommittee
! Latest revision --- 19 Mar 1980
!***REFERENCES JONES R.E., KAHANER D.K., "XERROR, THE SLATEC ERROR-
! HANDLING PACKAGE", SAND82-0800, SANDIA LABORATORIES,
! 1982.
!***ROUTINES CALLED I8MACH,S88FMT,XGETUA
!***END PROLOGUE XERSAV
INTEGER LUN(5)
CHARACTER*(*) MESSG
CHARACTER*20 MESTAB(10),MES
DIMENSION NERTAB(10),LEVTAB(10),KOUNT(10)
SAVE MESTAB,NERTAB,LEVTAB,KOUNT,KOUNTX
! NEXT TWO DATA STATEMENTS ARE NECESSARY TO PROVIDE A BLANK
! ERROR TABLE INITIALLY
DATA KOUNT(1),KOUNT(2),KOUNT(3),KOUNT(4),KOUNT(5), &
KOUNT(6),KOUNT(7),KOUNT(8),KOUNT(9),KOUNT(10) &
/0,0,0,0,0,0,0,0,0,0/
DATA KOUNTX/0/
!***FIRST EXECUTABLE STATEMENT XERSAV
IF (NMESSG.GT.0) GO TO 80
! DUMP THE TABLE
IF (KOUNT(1).EQ.0) RETURN
! PRINT TO EACH UNIT
CALL X8GETUA(LUN,NUNIT)
DO 60 KUNIT=1,NUNIT
IUNIT = LUN(KUNIT)
IF (IUNIT.EQ.0) IUNIT = I8MACH(4)
! PRINT TABLE HEADER
WRITE (IUNIT,10)
10 FORMAT (32H0 ERROR MESSAGE SUMMARY/ &
51H MESSAGE START NERR LEVEL COUNT)
! PRINT BODY OF TABLE
DO 20 I=1,10
IF (KOUNT(I).EQ.0) GO TO 30
WRITE (IUNIT,15) MESTAB(I),NERTAB(I),LEVTAB(I),KOUNT(I)
15 FORMAT (1X,A20,3I10)
20 CONTINUE
30 CONTINUE
! PRINT NUMBER OF OTHER ERRORS
IF (KOUNTX.NE.0) WRITE (IUNIT,40) KOUNTX
40 FORMAT (41H0OTHER ERRORS NOT INDIVIDUALLY TABULATED=,I10)
WRITE (IUNIT,50)
50 FORMAT (1X)
60 CONTINUE
IF (NMESSG.LT.0) RETURN
! CLEAR THE ERROR TABLES
DO I=1,10
KOUNT(I) = 0
enddo
KOUNTX = 0
RETURN
80 CONTINUE
! PROCESS A MESSAGE...
! SEARCH FOR THIS MESSG, OR ELSE AN EMPTY SLOT FOR THIS MESSG,
! OR ELSE DETERMINE THAT THE ERROR TABLE IS FULL.
MES = MESSG
DO 90 I=1,10
II = I
IF (KOUNT(I).EQ.0) GO TO 110
IF (MES.NE.MESTAB(I)) GO TO 90
IF (NERR.NE.NERTAB(I)) GO TO 90
IF (LEVEL.NE.LEVTAB(I)) GO TO 90
GO TO 100
90 CONTINUE
! THREE POSSIBLE CASES...
! TABLE IS FULL
KOUNTX = KOUNTX+1
ICOUNT = 1
RETURN
! MESSAGE FOUND IN TABLE
100 KOUNT(II) = KOUNT(II) + 1
ICOUNT = KOUNT(II)
RETURN
! EMPTY SLOT FOUND FOR NEW MESSAGE
110 MESTAB(II) = MES
NERTAB(II) = NERR
LEVTAB(II) = LEVEL
KOUNT(II) = 1
ICOUNT = 1
RETURN
END
SUBROUTINE X8GETUA(IUNITA,N)
!***BEGIN PROLOGUE XGETUA
!***DATE WRITTEN 790801 (YYMMDD)
!***REVISION DATE 820801 (YYMMDD)
!***CATEGORY NO. R3C
!***KEYWORDS ERROR,XERROR PACKAGE
!***AUTHOR JONES, R. E., (SNLA)
!***PURPOSE Returns unit number(s) to which error messages are being
! sent.
!***DESCRIPTION
! Abstract
! XGETUA may be called to determine the unit number or numbers
! to which error messages are being sent.
! These unit numbers may have been set by a call to XSETUN,
! or a call to XSETUA, or may be a default value.
!
! Description of Parameters
! --Output--
! IUNIT - an array of one to five unit numbers, depending
! on the value of N. A value of zero refers to the
! default unit, as defined by the I8MACH machine
! constant routine. Only IUNIT(1),...,IUNIT(N) are
! defined by XGETUA. The values of IUNIT(N+1),...,
! IUNIT(5) are not defined (for N .LT. 5) or altered
! in any way by XGETUA.
! N - the number of units to which copies of the
! error messages are being sent. N will be in the
! range from 1 to 5.
!
! Latest revision --- 19 MAR 1980
! Written by Ron Jones, with SLATEC Common Math Library Subcommittee
!***REFERENCES JONES R.E., KAHANER D.K., "XERROR, THE SLATEC ERROR-
! HANDLING PACKAGE", SAND82-0800, SANDIA LABORATORIES,
! 1982.
!***ROUTINES CALLED J84SAVE
!***END PROLOGUE XGETUA
DIMENSION IUNITA(5)
!***FIRST EXECUTABLE STATEMENT XGETUA
N = J84SAVE(5,0,.FALSE.)
DO 30 I=1,N
INDEX = I+4
IF (I.EQ.1) INDEX = 3
IUNITA(I) = J84SAVE(INDEX,0,.FALSE.)
30 CONTINUE
RETURN
END
INTEGER FUNCTION I8MACH(I)
!***BEGIN PROLOGUE I8MACH
!***DATE WRITTEN 750101 (YYMMDD)
!***REVISION DATE 840405 (YYMMDD)
!***CATEGORY NO. R1
!***KEYWORDS MACHINE CONSTANTS
!***AUTHOR FOX, P. A., (BELL LABS)
! HALL, A. D., (BELL LABS)
! SCHRYER, N. L., (BELL LABS)
!***PURPOSE Returns integer machine dependent constants
!***DESCRIPTION
!
! This is the CMLIB version of I8MACH, the integer machine
! constants subroutine originally developed for the PORT library.
!
! I8MACH can be used to obtain machine-dependent parameters
! for the local machine environment. It is a function
! subroutine with one (input) argument, and can be called
! as follows, for example
!
! K = I8MACH(I)
!
! where I=1,...,16. The (output) value of K above is
! determined by the (input) value of I. The results for
! various values of I are discussed below.
!
! I/O unit numbers.
! I8MACH( 1) = the standard input unit.
! I8MACH( 2) = the standard output unit.
! I8MACH( 3) = the standard punch unit.
! I8MACH( 4) = the standard error message unit.
!
! Words.
! I8MACH( 5) = the number of bits per integer storage unit.
! I8MACH( 6) = the number of characters per integer storage unit.
!
! Integers.
! assume integers are represented in the S-digit, base-A form
!
! sign ( X(S-1)*A**(S-1) + ... + X(1)*A + X(0) )
!
! where 0 .LE. X(I) .LT. A for I=0,...,S-1.
! I8MACH( 7) = A, the base.
! I8MACH( 8) = S, the number of base-A digits.
! I8MACH( 9) = A**S - 1, the largest magnitude.
!