Also {&_1 1 .
On Mon, Dec 10, 2012 at 11:32 PM, Roger Hui <[email protected]>wrote:
> If you really are converting random boolean values to (1,_1) values,
> another possibility is _1&^ or _1^]; i.e. 0 to 1 and 1 to _1.
>
>
>
> On Mon, Dec 10, 2012 at 8:58 PM, Brian Schott <[email protected]>wrote:
>
>> timespacex
>> 6!:2 , 7!:2@]
>> am =:_1& (I.@:-.@]})
>> am2=: ((-&1) @ +:)
>> amd=: <:@:+:
>> aml=: _1 + +:
>> d=: 2 6 50000?.@$ 2
>> timespacex 'am"1 d'
>> 0.011278 1.05535e7
>> timespacex 'am2 d'
>> 0.187884 8.39091e6
>> timespacex 'amd d'
>> 0.004365 1.6779e7
>> timespacex 'aml d'
>> 0.004874 1.67789e7
>>
>> It looks like David's method is fastest and Peter's is most lean.
>> And Linda's method loses nothing relative to David's.
>> ----------------------------------------------------------------------
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>>
>
>
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