I am not sure that it is a Good Thing but it is
(to quote a recent comment by a user) probably
harmless, so I have tweaked the following cases
of rank-0 monads:
B I D X Q
<. 1 1 1
>. 1 1 1
+ 1 1 1 1 1
* 1
%: 1
| 1
The following benchmarks demonstrate the improvements:
J6.02x
x=: 1e6 [EMAIL PROTECTED] 2e9
ts=: 6!:2 , 7!:[EMAIL PROTECTED]
ts ']x'
2.05645e_6 512
ts '<.x'
2.05962e_6 576
ts '+x'
1.90164e_6 512
J6.01:
ts ']x'
1.89801e_6 512
ts '<.x'
0.00571713 4.19488e6
ts '+x'
0.00588315 4.19482e6
----- Original Message -----
From: Henry Rich <[EMAIL PROTECTED]>
Date: Wednesday, January 3, 2007 10:44 am
Subject: [Jprogramming] Special code for <. on integers?
> t =. ? 1000000 # 1000
> ts '] t'
> 4.21309e_6 640
> ts '<. t'
> 0.00720339 4.19494e6
>
> I am working on graphics display lists which need
> to end up as integers. They sometimes turn to
> floats when they are scaled, and then they have to
> be turned back into integers. To accommodate all
> the cases I have, I end up executing <. more times than
> is really necessary.
>
> Wouldn't it be a Good Thing for <. and >. to be fast NOPs
> (i. e. like ]) when applied to integer or Boolean arrays?
>
> I guess I can use <.^:(4 < 3!:0) but I still think the change
> is worthwhile.
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