Roger,
Because my C is so weak I could use some explanation in words of what the C
is doing, not in general, but to discuss the questions below.
Would you say that the basic approach that is being taken in DO's is more
like the APL\360 definition or more like the Extended definition. I guess I
am a little surprised that a Loop is required through both the x and the y
values. In the Dictionary entry for Index of is the following example,
where the y component is not an atom, but a string. Is that a typical case
for which y must be looped through as well as x? I thought maybe the answer
was yes, and tried.
A=: 'abcdefghijklmnopqrstuvwxyz'
m=: 5 4 $ 12{. A
m;(m i. 'efgh');(1{m);(4{m)
I then found a slight "anomaly" though, trying the APL\360 definition with
that example.
+/*./\m~:/'efgh'
1 5 5 5
5 1 5 5
5 5 1 5
5 5 5 1
However that "anomaly" was fixed by the Extended definition, so maybe
therein is an example of why the y value must be looped through, too.
+/*./\m~:/&:<"(_1+#$m)'efgh'
1
Can you comment, please?
Also, in the second DO there is a phrase like this: *z++=*h<0?xn:*h;
I am familiar with the B?T:F part of the phrase, but I have never seen a ++
followed by an assignment. Does that just add one to the result from the
assigned amount?
Oh, and thanks for posting your paper.
--
(B=)
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