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#^:_1 Improved

initial writing: 2003-03-19
last updated: 2004-10-26


The dyad #^:_1 expand has been made more efficient in time and space. For example:

   b=: ?1e6$2
   c=: (+/b)$'abcde'
   i=: ?(+/b)$1e6
   x=: ((+/b),10)$'abc'

   ts=: 6!:2 , 7!:2@]  NB. time and space
   ts 'expression'
Expression     J 5.02    J 5.01    Ratio
b #^:_1 c   0.0356981   1.04966e6  0.1568434   1.10112e7  4.39   10.49
b #^:_1 i  0.0523209   4.19539e6  0.1987772   1.57298e7  3.80     3.75
b #^:_1 x   0.1566205   1.67783e7  0.3405053   3.46042e7  2.17     2.06




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