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authorjulie <julielangou@users.noreply.github.com>2011-11-01 22:02:31 +0000
committerjulie <julielangou@users.noreply.github.com>2011-11-01 22:02:31 +0000
commitd5c30c90bdecf38da1064e2ed52583634573e741 (patch)
tree480fc5ff31ee14b83116b6428aad79ea6e89362d /SRC/dsysvxx.f
parent04670a68760fa27333f8bcef8172f71adc6880ef (diff)
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Never say never...
Diffstat (limited to 'SRC/dsysvxx.f')
-rw-r--r--SRC/dsysvxx.f60
1 files changed, 20 insertions, 40 deletions
diff --git a/SRC/dsysvxx.f b/SRC/dsysvxx.f
index de61c010..84953d35 100644
--- a/SRC/dsysvxx.f
+++ b/SRC/dsysvxx.f
@@ -167,8 +167,7 @@
*> N-by-N lower triangular part of A contains the lower
*> triangular part of the matrix A, and the strictly upper
*> triangular part of A is not referenced.
-*> \endverbatim
-*> \verbatim
+*>
*> On exit, if FACT = 'E' and EQUED = 'Y', A is overwritten by
*> diag(S)*A*diag(S).
*> \endverbatim
@@ -186,8 +185,7 @@
*> contains the block diagonal matrix D and the multipliers
*> used to obtain the factor U or L from the factorization A =
*> U*D*U**T or A = L*D*L**T as computed by DSYTRF.
-*> \endverbatim
-*> \verbatim
+*>
*> If FACT = 'N', then AF is an output argument and on exit
*> returns the block diagonal matrix D and the multipliers
*> used to obtain the factor U or L from the factorization A =
@@ -213,8 +211,7 @@
*> diagonal block. If UPLO = 'L' and IPIV(k) = IPIV(k+1) < 0,
*> then rows and columns k+1 and -IPIV(k) were interchanged
*> and D(k:k+1,k:k+1) is a 2-by-2 diagonal block.
-*> \endverbatim
-*> \verbatim
+*>
*> If FACT = 'N', then IPIV is an output argument and on exit
*> contains details of the interchanges and the block
*> structure of D, as determined by DSYTRF.
@@ -325,37 +322,31 @@
*> For each right-hand side, this array contains information about
*> various error bounds and condition numbers corresponding to the
*> normwise relative error, which is defined as follows:
-*> \endverbatim
-*> \verbatim
+*>
*> Normwise relative error in the ith solution vector:
*> max_j (abs(XTRUE(j,i) - X(j,i)))
*> ------------------------------
*> max_j abs(X(j,i))
-*> \endverbatim
-*> \verbatim
+*>
*> The array is indexed by the type of error information as described
*> below. There currently are up to three pieces of information
*> returned.
-*> \endverbatim
-*> \verbatim
+*>
*> The first index in ERR_BNDS_NORM(i,:) corresponds to the ith
*> right-hand side.
-*> \endverbatim
-*> \verbatim
+*>
*> The second index in ERR_BNDS_NORM(:,err) contains the following
*> three fields:
*> err = 1 "Trust/don't trust" boolean. Trust the answer if the
*> reciprocal condition number is less than the threshold
*> sqrt(n) * dlamch('Epsilon').
-*> \endverbatim
-*> \verbatim
+*>
*> err = 2 "Guaranteed" error bound: The estimated forward error,
*> almost certainly within a factor of 10 of the true error
*> so long as the next entry is greater than the threshold
*> sqrt(n) * dlamch('Epsilon'). This error bound should only
*> be trusted if the previous boolean is true.
-*> \endverbatim
-*> \verbatim
+*>
*> err = 3 Reciprocal condition number: Estimated normwise
*> reciprocal condition number. Compared with the threshold
*> sqrt(n) * dlamch('Epsilon') to determine if the error
@@ -364,8 +355,7 @@
*> appropriately scaled matrix Z.
*> Let Z = S*A, where S scales each row by a power of the
*> radix so all absolute row sums of Z are approximately 1.
-*> \endverbatim
-*> \verbatim
+*>
*> See Lapack Working Note 165 for further details and extra
*> cautions.
*> \endverbatim
@@ -376,14 +366,12 @@
*> For each right-hand side, this array contains information about
*> various error bounds and condition numbers corresponding to the
*> componentwise relative error, which is defined as follows:
-*> \endverbatim
-*> \verbatim
+*>
*> Componentwise relative error in the ith solution vector:
*> abs(XTRUE(j,i) - X(j,i))
*> max_j ----------------------
*> abs(X(j,i))
-*> \endverbatim
-*> \verbatim
+*>
*> The array is indexed by the right-hand side i (on which the
*> componentwise relative error depends), and the type of error
*> information as described below. There currently are up to three
@@ -391,26 +379,22 @@
*> componentwise accuracy is not requested (PARAMS(3) = 0.0), then
*> ERR_BNDS_COMP is not accessed. If N_ERR_BNDS .LT. 3, then at most
*> the first (:,N_ERR_BNDS) entries are returned.
-*> \endverbatim
-*> \verbatim
+*>
*> The first index in ERR_BNDS_COMP(i,:) corresponds to the ith
*> right-hand side.
-*> \endverbatim
-*> \verbatim
+*>
*> The second index in ERR_BNDS_COMP(:,err) contains the following
*> three fields:
*> err = 1 "Trust/don't trust" boolean. Trust the answer if the
*> reciprocal condition number is less than the threshold
*> sqrt(n) * dlamch('Epsilon').
-*> \endverbatim
-*> \verbatim
+*>
*> err = 2 "Guaranteed" error bound: The estimated forward error,
*> almost certainly within a factor of 10 of the true error
*> so long as the next entry is greater than the threshold
*> sqrt(n) * dlamch('Epsilon'). This error bound should only
*> be trusted if the previous boolean is true.
-*> \endverbatim
-*> \verbatim
+*>
*> err = 3 Reciprocal condition number: Estimated componentwise
*> reciprocal condition number. Compared with the threshold
*> sqrt(n) * dlamch('Epsilon') to determine if the error
@@ -421,8 +405,7 @@
*> current right-hand side and S scales each row of
*> A*diag(x) by a power of the radix so all absolute row
*> sums of Z are approximately 1.
-*> \endverbatim
-*> \verbatim
+*>
*> See Lapack Working Note 165 for further details and extra
*> cautions.
*> \endverbatim
@@ -441,8 +424,7 @@
*> that entry will be filled with default value used for that
*> parameter. Only positions up to NPARAMS are accessed; defaults
*> are used for higher-numbered parameters.
-*> \endverbatim
-*> \verbatim
+*>
*> PARAMS(LA_LINRX_ITREF_I = 1) : Whether to perform iterative
*> refinement or not.
*> Default: 1.0D+0
@@ -450,8 +432,7 @@
*> computed.
*> = 1.0 : Use the extra-precise refinement algorithm.
*> (other values are reserved for future use)
-*> \endverbatim
-*> \verbatim
+*>
*> PARAMS(LA_LINRX_ITHRESH_I = 2) : Maximum number of residual
*> computations allowed for refinement.
*> Default: 10
@@ -461,8 +442,7 @@
*> Gaussian elimination, the guarantees in
*> err_bnds_norm and err_bnds_comp may no longer be
*> trustworthy.
-*> \endverbatim
-*> \verbatim
+*>
*> PARAMS(LA_LINRX_CWISE_I = 3) : Flag determining if the code
*> will attempt to find a solution with small componentwise
*> relative error in the double-precision algorithm. Positive