I have been studying dyadic I. recently in
connection with Roger Hui's jwiki Essays/Histogram
http://www.jsoftware.com/jwiki/Essays/Histogram . In doing
so I became aware of the effect of *reversing* the
*ascending* x argument of dyadic I. .
To extend an example in the dictionary at
http://www.jsoftware.com/help/dictionary/dicapdot.htm
consider and compare the verb Idotr relative to I. as shown
below.
Idotr =: |[EMAIL PROTECTED] ([EMAIL PROTECTED]) ]
0 2 2 5 (I.,:Idotr) _5 1 2 3 9 0
0 1 1 3 4 0
0 1 3 3 4 1
I have found Idotr is more useful for histogram
construction than I. for my applications.
On Sun, 21 Jan 2007, Joey K Tuttle wrote:
+
+ Perhaps you were thinking of something like Interval Index, dyadic I.
+ which is new in j6 - very nice/efficient new capability...
+
+ [dat=:2*i.10
+ 0 2 4 6 8 10 12 14 16 18
+ dat I. 6
+ 3
+ dat I. 7
+ 4
+ dat I. 6 7
+ 3 4
+
(B=) <----------my "sig"
Brian Schott
Atlanta, GA, USA
schott DOT bee are eye eh en AT gee em ae eye el DOT com
http://schott.selfip.net/~brian/
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