Yes, I should have added that the fast path applies only when y is a
list of boxes.
10000 ts '0 {:: a' [ a =. ;:'words and words'
3.14994e_7 832
10000 ts '0 >@{ a' [ a =. ;:'words and words'
4.43897e_7 1024
You need much more than 10 repetitions to measure time on such short
executions.
This is not very accurate because you are including the cost of
tokenizing and parsing, which is comparable to the time spent in the verb.
Henry Rich
On 9/19/2018 1:51 PM, 'Pascal Jasmin' via Programming wrote:
on beta g
10 timespacex '(0 {:: ]) ,1'
1.53889e_6 1728
10 timespacex '(0 >@{ ]) 1'
7.12448e_7 1088
10 timespacex '(0 >@{ ]) ,1'
7.97941e_7 1536
similar results with adverb form.
50 timespacex '(0 (&({::))(@:])) 1 2'
1.50469e_6 224050 timespacex '0(&(>@{))(@:]) 1 2'
1.3394e_6 1920
________________________________
From: Henry Rich <[email protected]>
To: [email protected]
Sent: Wednesday, September 19, 2018 1:38 PM
Subject: Re: [Jprogramming] should 0 {:: scalar return that scalar instead of
being a length error?
I modified {:: some time back to handle the case where x is a scalar or
has boxes that contain scalars, and I'm pretty sure that's the fastest
way to extract a single box's contents.
Henry Rich
On 9/19/2018 1:32 PM, 'Pascal Jasmin' via Programming wrote:
My main motivation for the proposal is related to a favorite adverb:
Y =: (&({::))(@:])
but it turns out that
X =: (&(>@{))(@[)
is faster and has the convenience of easily selecting multiple items from what
is usually a record format for either argument, as well as not failing on a
scalar argument.
so >@{ is a better {:: for many common applications.
________________________________
From: Raul Miller <[email protected]>
To: Programming forum <[email protected]>
Sent: Wednesday, September 19, 2018 11:31 AM
Subject: Re: [Jprogramming] should 0 {:: scalar return that scalar instead of
being a length error?
If we're going to talk about composites, and unboxing the first item,
I would imagine that things like >@{. should be considered.
Note that this approach has another advantage - we don't have to worry
about whether the word to its left is numeric (which can happen if
this verb gets used in an adverbial or conjunctive context).
Thanks,
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