When it's just two (or a small fixed number) of
verbs you can dispense with gerunds:
((+/&.>(-.b)#list) , $&.>b#list) /: /:b
+-+-+-+--+-+-+
|3|4|3|19|2|5|
+-+-+-+--+-+-+
Or, if you can afford to, apply both verbs to
the entire list and pick and choose from the
results:
b} (+/&.> ,: $&.>) list
+-+-+-+--+-+-+
|3|4|3|19|2|5|
+-+-+-+--+-+-+
----- Original Message -----
From: Mike Powell <[EMAIL PROTECTED]>
Date: Wednesday, October 25, 2006 12:15 pm
Subject: [Jprogramming] Apply to items
> I have a list of vectors of two types. Each vector needs to be
> processed by a monadic function according to the corresponding
> element of a boolean. I'm trying to do this by constructing a
> gerund
> and applying this item by item to the list (with an explicit or
> implied pre-open and post-box). I'm stuck. For example:
>
> b =: 0 1 1 0 1 1
> g=:+/`$
> list=:1 2;3 4 5 6;8 8 8; 9 2 4 1 3;1 2; 5 5 5 5 5
>
> (b{g) apply list
>
> 3;4;3;19;2;5
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