public interface sptrd
SPTRD reduces a real symmetric matrix A stored in packed form to
symmetric tridiagonal form T by an orthogonal similarity
transformation: Q**T * A * Q = T.
Subroutines
Arguments
| Type |
Intent | Optional | Attributes |
|
Name |
|
|
character(len=1),
|
intent(in) |
|
|
:: |
uplo |
|
|
integer(kind=ilp),
|
intent(in) |
|
|
:: |
n |
|
|
real(kind=dp),
|
intent(inout) |
|
|
:: |
ap(*) |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
d(*) |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
e(*) |
|
|
real(kind=dp),
|
intent(out) |
|
|
:: |
tau(*) |
|
|
integer(kind=ilp),
|
intent(out) |
|
|
:: |
info |
|
Arguments
| Type |
Intent | Optional | Attributes |
|
Name |
|
|
character(len=1),
|
intent(in) |
|
|
:: |
uplo |
|
|
integer(kind=ilp),
|
intent(in) |
|
|
:: |
n |
|
|
real(kind=sp),
|
intent(inout) |
|
|
:: |
ap(*) |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
d(*) |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
e(*) |
|
|
real(kind=sp),
|
intent(out) |
|
|
:: |
tau(*) |
|
|
integer(kind=ilp),
|
intent(out) |
|
|
:: |
info |
|
Module Procedures