Description

Multiple-Instance 2-norm - The multiple-instance 2-norm routine, S3L_2_norm, computes one or more instances of the 2-norm of a vector. The single-instance 2-norm routine, S3L_gbl_2_norm, computes the global 2-norm of a parallel array.

For each instance z of z, the multiple-instance routine S3L_2_norm performs the operation shown in Table 8-1.

Table 8-1 S3L Multiple-Instance 2-norm Operations

Operation	Data Type
z = (xTx)1/2 = ||x||(2)	real
z = (xHx)1/2 = ||x||(2)	complex

Upon successful completion, S3L_2_norm overwrites each element of z with the 2-norm of the corresponding vector in x.

Single-Instance 2-norm - The single-instance routine S3L_gbl_2_norm routine performs the operations shown in Table 8-2.

Table 8-2 S3L Single-Instance 2-norm Operations

Operation	Data Type
a = (xTx)1/2 = ||x||(2)	real
a = (xHx)1/2 = ||x||(2)	complex

Upon successful completion, S3L_gbl_2_norm overwrites a with the global 2-norm of x.