Visible to Intel only — GUID: GUID-CF75E14C-C618-4C59-A8B9-5E6BCF0030D9
Visible to Intel only — GUID: GUID-CF75E14C-C618-4C59-A8B9-5E6BCF0030D9
?lasorte
Sorts eigenpairs by real and complex data types.
Syntax
call slasorte(s, lds, j, out, info)
call dlasorte(s, lds, j, out, info)
Description
The ?lasorteroutine sorts eigenpairs so that real eigenpairs are together and complex eigenpairs are together. This helps to employ 2x2 shifts easily since every second subdiagonal is guaranteed to be zero. This routine does no parallel work and makes no calls.
Product and Performance Information |
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Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex. Notice revision #20201201 |
Input Parameters
- s
-
(local)
REAL for slasorte
DOUBLE PRECISION for dlasorte
Array of size lds.
On entry, a matrix already in Schur form.
- lds
-
(local) INTEGER.
On entry, the leading dimension of the array s; unchanged on exit.
- j
-
(local) INTEGER.
On entry, the order of the matrix S; unchanged on exit.
- out
-
(local)
REAL for slasorte
DOUBLE PRECISION for dlasorte
Array of size 2*j. The work buffer required by the routine.
- info
-
(local) INTEGER.
Set, if the input matrix had an odd number of real eigenvalues and things could not be paired or if the input matrix S was not originally in Schur form. 0 indicates successful completion.
Output Parameters
- s
-
On exit, the diagonal blocks of S have been rewritten to pair the eigenvalues. The resulting matrix is no longer similar to the input.
- out
-
Work buffer.