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NAG[f07hsc] NAG[nag_zpbtrs] - Solution of complex Hermitian positive-definite band system of linear equations, multiple right-hand sides, matrix already factorized by f07hrc (nag_zpbtrf)
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Calling Sequence
f07hsc(uplo, kd, ab, b, 'n'=n, 'nrhs'=nrhs, 'fail'=fail)
nag_zpbtrs(. . .)
Parameters
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uplo - String;
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Constraint:   "Nag_Upper" or "Nag_Lower". .
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kd - integer;
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On entry:  , the number of superdiagonals or subdiagonals of the matrix  .
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Constraint:  . .
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ab - 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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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 second dimension of the array ab.
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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_zpbtrs (f07hsc) solves a complex Hermitian positive-definite band system of linear equations with multiple right-hand sides,
where  has been factorized by f07hrc (nag_zpbtrf).
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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:  .
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  , assuming  .
This function may be followed by a call to f07hvc (nag_zpbrfs) to refine the solution and return an error estimate.
The real analogue of this function is f07hec (nag_dpbtrs).
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Examples
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uplo := "Nag_Lower":
n := 4:
kd := 1:
nrhs := 2:
ab := Matrix([[0 +0*I , 3.064310689208912 +0*I , 0.3524446799090123 +0.5645641631875845*I , 1.116713953189507 +0*I ], [-0.03581937870996762 -0.2596904956472652*I , 1.606635558731136 +0*I , -0.2053981677466558 -1.394217865916694*I , 0.428915067402645 +0*I ]], datatype=complex[8], order='C_order'):
b := Matrix([[-12.42 +68.42*I , 54.3 -56.56*I ], [-9.93 +0.88*I , 18.32 +4.76*I ], [-27.3 -0.01*I , -4.4 +9.970000000000001*I ], [5.31 +23.63*I , 9.43 +1.41*I ]], datatype=complex[8], order='C_order'):
NAG:-f07hsc(uplo, kd, ab, b, 'n' = n, 'nrhs' = nrhs):
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