Yes, I should have explained the output, and stress that
it's really for large scalars >= 2^31, but you can force it to
use its procedure for smallish numbers, eg
0 primepi 100 NB. might not align...
100 50 33 25 20 16 14 12 11 10 9 8 7 6 5 4 3 2 1
25 15 11 9 8 6 6 5 5 4 4 4 4 3 3 2 2 1 0
So you get primepi for n and for a number of
sieve values < n, eg pi(33) = 11 etc.
I've left the table output as being of potential
use, although one's principal interest is in
{.{:primepi n
0 primepi each 2 3 4
+---+-----+-----+
|2 1|3 2 1|4 2 1|
|1 0|2 1 0|2 1 0|
+---+-----+-----+
shows the results a bit better than the zero rank version.
Pascal Jasmin (is it?) points out that a <.@%: b is
preferable to <. a % b. Oversight, sorry!
Thanks, both,
Mike
On 25/02/2015 17:03, Raul Miller wrote:
I tried your primepi, and I'm not certain I understand it. It seems to
me that its behavior above the threshold is very different from that
of pi:
pi i. 10
0 0 1 2 2 3 3 4 4 4
pi 2 3 4
1 2 2
primepi 2 3 4
1 2 2
1 primepi 2 3 4
|length error: primepi
| V=.<.n %i=.>:i.r
1 primepi("0) 2 3 4
2 1 0
1 0 0
3 2 1
2 1 0
4 2 1
2 1 0
Was this the code that you meant to post?
Thanks,
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