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#909 Method 'infinity_norm' does not actually compute the infinity norm

Metadata

Property Value
Reported by Oliver Sander (oliver.sander@tu-dresden.de)
Reported at Apr 26, 2011 21:01
Type Bug Report
Version Git (pre2.4) [autotools]
Operating System Unspecified / All

Description

I would expect a method called 'infinity_norm' of a matrix to compute the infinity norm: the maximum of the absolute values of all entries. However at least the implementations in DenseMatrix, BCRSMatrix, and Matrix compute something else, namely the maximum over the 1-norms of the matrix rows. This is a flagrant violation of the principle of least surprise.

The fix is easy, however apparently the behavior is intentional. At least it is mentioned in the documentation. Why would I need such a strange norm? And isn't there a better name for it?