--- ais/ai-00418.txt 2005/03/11 21:41:33 1.2 +++ ais/ai-00418.txt 2005/04/13 05:37:24 1.3 @@ -42,6 +42,13 @@ while the final norm does not. An implementation cannot merely return Sqrt (X * X), it has to cope with a possible overflow of the inner product. +AARM Implementation Note: While the definition is given in terms of +an inner product, the norm doesn't "involve an inner product" in the +technical sense. The reason is that is has accuracy requirements +substantially different from those applicable to inner products; and that +cancellations cannot occur, because all the terms are positive, so there +is no possibility of intermediate overflow. + Add after G.3.1(81): For the L2-norm, no accuracy requirements are specified in the relaxed mode. In @@ -64,6 +71,13 @@ This operation returns the Hermitian L2-norm of Right (the square root of the inner product of the vector with its conjugate). + +AARM Implementation Note: While the definition is given in terms of +an inner product, the norm doesn't "involve an inner product" in the +technical sense. The reason is that is has accuracy requirements +substantially different from those applicable to inner products; and that +cancellations cannot occur, because all the terms are positive, so there +is no possibility of intermediate overflow. Add after G.3.2(150):

Questions? Ask the ACAA Technical Agent