sumsq_i(3PI) Sun Interval Performance Library sumsq_i(3PI)NAMEsumsq_i - Sum of squares.
DESCRIPTION
The routine SUMSQ_I returns the intervals SCL and SSQ such that SCL**2
* SSQ = SCALE**2 * SUMSQ + SUM_OF_Xi
If N is equal to zero, the routine returns immediately with SCL and SSQ
unchanged.
SYNOPSIS
SUBROUTINE SUMSQ_I( X, SSQ, SCL )
INTERVAL, INTENT(IN) :: X(:)
INTERVAL, INTENT(INOUT) :: SSQ, SCL
where
X has shape (N).
ARGUMENTS
X (input)
Array of DIMENSION N.
Unchanged on exit.
SCL(input/output)
Scalar element.
On entry, has value SCALE - any valid positive
interval, i.e. INF(SCALE) > 0.
On exit, SCL is overwritten by result of subroutine,
the degenerate interval
SCL = MAX for all X entries of SCALE and ABS(Xi).
SSQ (input/output)
Scalar element.
On entry, has value SUMSQ such that
ABS(SSQ) >= 1.0
On exit, SSQ has the value:
1.0 <= SSQ <= (SUMSQ + N) such that
SSQ = (SCALE**2 * SUMSQ + SUM_OF_Xi)/SCL**2
ERRORS
blas_error_alloc
X is unallocated array
blas_error_scl
INF(SCALE) < 0
6 Mar 2009 sumsq_i(3PI)