norm {Matrix} | R Documentation |
Computes a matrix norm of x
using Lapack. The norm can be
the one norm, the infinity norm, the Frobenius norm, or the maximum
modulus among elements of a matrix, as determined by the value of
type
.
norm(x, type, ...)
x |
a real or complex matrix. |
type |
A character indicating the type of norm desired.
"O" or "o" or "1" specifies the one norm,
(maximum absolute column sum);
"I" or "i" specifies the infinity norm (maximum
absolute row sum);
"F" or "f" specifies the Frobenius norm (the
Euclidean norm of x treated as if it were a vector);
and "M" or "m" specifies the maximum modulus of
all the elements in x . The default is "O" .
Only the first character of type[1] is used.
|
... |
further arguments passed to or from other methods. |
Based on the Lapack functions dlange
, dlansy
, dlantr
,
zlange
, zlansy
, and zlantr
.
A numeric value of class "norm"
, representing the quantity
chosen according to type
.
Anderson, E., et al. (1994). LAPACK User's Guide, 2nd edition, SIAM, Philadelphia.
x <- Hilbert(9) norm(x, "1") norm(x, "I") norm(x, "F") norm(x, "M")