OK> (/:@({~ i.~) -: tgu3) x
1
I am in a state of shock !
Roger ! I can't believe my eyes on the difference in speed of the i.
implementation versus dyadic iota in APL why is it so ?
I would qualify Oleg's solution as the "pure J" solution and it should be
the "pure APL" solution too but...
Oleg's solution can't be implemented in APL because it is about 323
seconds with an x which is ten times smaller. No APL'er I know would have
taken this simple approach because they are brain damaged by their APL
implementation.
History: Us APL'ers have been influenced by the quality of implementations
of APL interpreters. It would have never crossed my mind to use dyadic
iota (i. for J'ers) in such a straight forward manner. Why ? Because it is
slow as a dog in all APL interpreters I currently know.
I remember several conversations with various APL'ers about how some
"motivated newbies" wanted to implement a "faster dyadic iota" rather than
doing the "right thing" and move forward... Or was it really backward ?
Conclusion: Even older APL'ers have to understand the influences of the
implementations they worked on and they should throw all that knowledge
away because J's implementation makes it really clear that the particulars
of any/all APL interpreters have short-circuit their brain away from the
simplicity of the language.
NB. I am so shocked that I am preparing a white paper on this very issue
for our APL team. The title could be:
"How APL implementations have ruined your pure APL thinking and why J can
restore it..."
Paul Gauthier
APL Software Developer - Senior
[EMAIL PROTECTED]
Phone: 312-739-3467
Fax: 312-739-3496
CheckFree. The Company that Powers Payment on the WebSM.
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