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NAG[f07psc] NAG[nag_zhptrs] - Solution of complex Hermitian indefinite system of linear equations, multiple right-hand sides, matrix already factorized by f07prc (nag_zhptrf), packed storage
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Calling Sequence
f07psc(uplo, ap, ipiv, b, 'n'=n, 'nrhs'=nrhs, 'fail'=fail)
nag_zhptrs(. . .)
Parameters
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uplo - String;
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On entry: indicates how  has been factorized.
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Constraint:   "Nag_Upper" or "Nag_Lower". .
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ap - Vector(1..dim, datatype=complex[8]);
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Note: the dimension, dim, of the array ap must be at least  .
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On entry: details of the factorization of  stored in packed form, as returned by f07prc (nag_zhptrf).
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ipiv - Vector(1..dim, datatype=integer[kernelopts('wordsize')/8]);
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Note: the dimension, dim, of the array ipiv must be at least  .
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On entry: details of the interchanges and the block structure of  , as returned by f07prc (nag_zhptrf).
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b - Matrix(1..dim1, 1..dim2, datatype=complex[8], order=order);
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Note: this array may be supplied in Fortran_order or C_order , as specified by order. All array parameters must use a consistent order.
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'n'=n - integer; (optional)
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Default value: the dimension of the array ap.
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On entry:  , the order of the matrix  .
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Constraint:  . .
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'nrhs'=nrhs - integer; (optional)
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Default value: the second dimension of the array b.
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On entry:  , the number of right-hand sides.
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Constraint:  . .
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'fail'=fail - table; (optional)
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The NAG error argument, see the documentation for NagError.
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Description
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Purpose
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nag_zhptrs (f07psc) solves a complex Hermitian indefinite system of linear equations with multiple right-hand sides,
where  has been factorized by f07prc (nag_zhptrf), using packed storage.
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Error Indicators and Warnings
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"NE_ALLOC_FAIL"
Dynamic memory allocation failed.
"NE_BAD_PARAM"
On entry, argument  had an illegal value.
"NE_INT"
On entry,  . Constraint:  .
On entry,  . Constraint:  .
"NE_INTERNAL_ERROR"
An internal error has occurred in this function. Check the function call and any array sizes. If the call is correct then please consult NAG for assistance.
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Further Comments
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The total number of real floating-point operations is approximately  .
This function may be followed by a call to f07pvc (nag_zhprfs) to refine the solution and return an error estimate.
The real analogue of this function is f07pec (nag_dsptrs).
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Examples
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uplo := "Nag_Lower":
n := 4:
nrhs := 2:
ap := Vector([-4.981630459440283 +0*I, 0.210214907090655 +0.1106935130516159*I, -7.724450141995383 +0*I, 0.3100287981271241 -0.04333020743962702*I, -0.1518120207240102 -0.3742958425613706*I, -1.36 +0*I, 0.5637050486508776 -0.2850349501519716*I, 0.339658279960361 -0.03031451811355639*I, 3.91 -1.5*I, -1.84 +0*I], datatype=complex[8], order='C_order'):
ipiv := Vector([1, 2, -1, -1], datatype=integer[kernelopts('wordsize')/8]):
b := Matrix([[7.79 +5.48*I , -35.39 +18.01*I ], [-0.77 -16.05*I , 4.23 -70.02*I ], [-9.58 +3.88*I , -24.79 -8.4*I ], [2.98 -10.18*I , 28.68 -39.89*I ]], datatype=complex[8], order='C_order'):
NAG:-f07psc(uplo, ap, ipiv, b, 'n' = n, 'nrhs' = nrhs):
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