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NAG[f07arc] NAG[nag_zgetrf] -  factorization of complex  by  matrix
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Calling Sequence
f07arc(a, ipiv, 'm'=m, 'n'=n, 'fail'=fail)
nag_zgetrf(. . .)
Parameters
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a - 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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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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'm'=m - integer; (optional)
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Default value: the first dimension of the array a.
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On entry:  , the number of rows of the matrix  .
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Constraint:  . .
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'n'=n - integer; (optional)
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Default value: the second dimension of the array a.
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On entry:  , the number of columns of the matrix  .
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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_zgetrf (f07arc) computes the  factorization of a complex  by  matrix.
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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.
"NE_SINGULAR"
 is exactly zero. The factorization has been completed but the factor  is exactly singular, and division by zero will occur if it is subsequently used to solve a system of linear equations or to invert  .
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Examples
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>
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m := 4:
n := 4:
a := Matrix([[-1.34 +2.55*I , 0.28 +3.17*I , -6.39 -2.2*I , 0.72 -0.92*I ], [-0.17 -1.41*I , 3.31 -0.15*I , -0.15 +1.34*I , 1.29 +1.38*I ], [-3.29 -2.39*I , -1.91 +4.42*I , -0.14 -1.35*I , 1.72 +1.35*I ], [2.41 +0.39*I , -0.5600000000000001 +1.47*I , -0.83 -0.6899999999999999*I , -1.96 +0.67*I ]], datatype=complex[8]):
ipiv := Vector(4, datatype=integer[kernelopts('wordsize')/8]):
NAG:-f07arc(a, ipiv, 'm' = m, 'n' = n):
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