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u"r Improved

initial writing: 2000-00-00
last updated: 2004-10-26


The rank operator u"r for a general verb u is now more efficient in the use of temporary arrays, resulting in improved performance in time (slightly) and in space. In the time and space comparisons presented below, the result of 7!:3 is a 2-column table of block sizes and the number of available temps of that size.


   ts=: 6!:2 , 7!:2@]

   pi  =: 3 : 'o.y.'
   plus=: 4 : 'x.+y.'
   x=: o.?1e5$1e6
   y=: o.?1e5$1e6

J 4.05                         J 4.04

   7!:3                         7!:3 
  64 1207                        64 1097
 128 1130                       128 1109
 256  255                       256  277
 512   84                       512   84
1024   45                      1024   44

   ts 'pi"0 y'                    ts 'pi"0 y'
5.02835 1.05498e6              5.16796 1.4836e7

   7!:3                         7!:3 
  64 1207                        64 100425
 128 1130                       128   1109
 256  255                       256    277
 512   84                       512     84
1024   45                      1024    556

   ts 'x plus"0 y'                ts 'x plus"0 y'
5.45015 1.0553e6               5.5558 8.48902e6

   7!:3                         7!:3 
  64 1207                        64 100425
 128 1130                       128   1109
 256  255                       256    277
 512   84                       512     84
1024   45                      1024    556



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