This function is not yet fully documented. This is a transcript of the text-formatted help.

bbcount  Create a counting black-box operator.
   BB=bbcount(BB1) creates a black-box operator that counts the number of
   operations it has been used to compute. This is useful for debugging
   and benchmarking iterative algorithms.

   bbcount creates an object that keeps track of both matrix-matrix
   products and the equivalent numberof matrix-vector products. This count
   is shown by disp(BB) (just BB at the prompt), or it can be accessed
   with bbcountstat. bbcountreset can be used to reset a counters.

   bbclear must be used to remove an operator that includes a bbcount
   object. Otherwise you will be left with orphaned variables in the base

   For an example, see bbcountreset.

   Note 1: the object created by bbcount does not follow normal Matlab
   conventions. If a counter is copied, the copy refers to the same
   object. This behaviour is necessary to allow the object to be passed
   to functions (conceptually, Matlab always creates a copy), but it
   may be confusing.

   Note 2: it is difficult to implement bbcount efficiently in a clean
   manner. Ading a counter to a black-box matrix may slow down a
   computation noticably.

   See also bbcountstat, bbcountreset, bbclear.