f/@, Improved

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f/@, Improved | initial writing: 2000-00-00 last updated: 2004-10-21

The phrase`f/@,` is now supported by special code, for dense as well as sparse arrays. (Previously, it was supported by special code for sparse arrays only.) A time-space comparison is as follows:

       ts=: 6!:2 , 7!:2@]        NB. time-space

       x=: o. ?11 13 17 61$1000  NB. dense array
       s=: $. x * 0=?($x)$10     NB. sparse array with density of 0.1

J 4.05

       ts '+/@, x'
    0.00631756 2688
       ts '>./@, x'
    0.00842537 2688

       ts '+/@, s'
    0.000160914 1728
       ts '>./@, s'
    0.000274057 1728

J 4.04

       ts '+/@, x'
    0.0133911 2.09888e6
       ts '>./@, x'
    0.0170284 2.09888e6

       ts '+/@, s'
    0.000164267 1792
       ts '>./@, s'
    0.000271543 1792

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