Hi all !

Hopefully better examples this time.

   v=.v?v=.10000000
   #v
10000000
   10 {. v
9257364 5642952 2724566 7608992 7025081 5624810 5911207 1606397 5366536 5408278

As we can see here, there is a space penalty for using @: compared to [: f ]. This space penalty is removed with proper use of brackets. There is a space advantage and a serious time penalty for using @ instead.
   ts'([:-[:-[:-[:-]) v'
0.236697 2.68438e8
   ts'(-@:-@:-@:-@:]) v'
0.236098 5.36874e8
   ts'(-@:(-@:(-@:(-@:])))) v'
0.245187 2.68439e8
   ts' (-@-@-@-@]) v'
6.38008 1.34222e8

Cheers,
Erling Hellenäs



On 2017-09-29 16:01, Erling Hellenäs wrote:
Sorry, these were stupid examples. I'll come back. /Erling

On 2017-09-29 15:53, Erling Hellenäs wrote:
Hi all!

From these simple examples it does not seem to be any difference in time and space requirements between the [:+] syntax and the +@:] syntax. Not even if we insert more brackets.

     ts'(i.v) ([:+[:+[:+[:+]) i.v=.1000000'

0.00936323 1.67808e7

ts'(i.v) (+@:+@:+@:+@:]) i.v=.1000000'

0.00935086 1.67808e7

ts'(i.v) (+@:(+@:(+@:(+@:])))) i.v=.1000000'

0.00925313 1.67811e7


As we can see using @ instead of @: has a heavy penalty in both time and space  requirements.


ts'(i.v) (+@+@+@+@]) i.v=.1000000'

0.341589 1.69553e8


Cheers,

Erling


On 2017-09-29 05:31, Henry Rich wrote:
It seems a bit much to ask Raul to track down a recent email thread.

No, @: does not create a namespace.  Only explicit entities have a namespace.

Henry Rich

On 9/28/2017 11:19 PM, Erling Hellenäs wrote:
On 2017-09-29 04:59, Raul Miller wrote:
I do not know of any definition of "namespace" such that @: creates a namespace.

Why do you think that @: creates a namespace?

Thanks,

As I said there was a discussion about this in a long thread recently. Maybe you can find it? This is from what I remember of this thread, it's not from my  own investigations.

/Erling

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