Equivalence of functions typically means "equivalence over a given domain".
Thus, if you are concerned with domain which is limited enough, it's
trivial:
'is a' (f -: g) b
1
Likewise, it can be trivial to show that they are not equivalent over
domains where their definitions give different results:
' ' (f -: g) b
0
And, of course, if you are dealing with "unbounded domains" then you may
have an unbounded problem (though exceptions will exist and careful
analysis may make the problems more tractable).
--
Raul
On Thursday, November 10, 2011, Linda Alvord <[email protected]>
wrote:
> a=: 0 : 0
> a is a
> b is not a
> c is a or not a
> )
> a
> a is a
> b is not a
> c is a or not a
>
> b=: <;._2 a
> b
> -------T----------T---------------┐
> │a is a│b is not a│c is a or not a│
> L------+----------+----------------
>
> f=: 13 :'x&(+./@E.)&>y'
> f
> 4 : 'x&(+./@E.)&>y'
>
> 'is a' f b
> 1 0 1
>
> 'not a' f b
> 0 1 1
>
> Also:
>
> g=: 13 :'+/"1 x E."1 > y'
> g
> [: +/"1 [ E."1 [: > ]
>
> 'is a' g b
> 1 0 1
>
> 'not a' g b
> 0 1 1
>
> Is there a way to determine if f and g are the same if they are used
> dyadically?
>
>
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]] On Behalf Of Roger Hui
> Sent: Thursday, November 10, 2011 12:45 PM
> To: Programming forum
> Subject: Re: [Jprogramming] Boxing and Finding
>
> 1. t=: <;._2 s
> 2. 'sub'&(+./@E.)&> t
>
>
>
> On Thu, Nov 10, 2011 at 9:36 AM, Skip Cave <[email protected]>
wrote:
>> Two questions,
>>
>> 1. I have a text array where each line is terminated with a line feed.
How
>> do you box each line of that text array to create an array of boxed text
>> strings?
>>
>> 2. When you have an array of boxed text strings, how do you create a
>> boolean array that indicates which boxes contain a particular text
string?
>>
>> Skip
>> ----------------------------------------------------------------------
>> For information about J forums see http://www.jsoftware.com/forums.htm
>>
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
