[Jprogramming] Parsing trains

[Tracy Harms]

A year ago Rob Hodgkinson pointed me to the following definition of
the first-order difference of a vector.
   diff =: }. - }:

I wanted to find a way to specify the order-of-difference as a left
argument.  Henry Rich refined that as the following adverb:
   fd=: (}. - }:) ^:

It's still among my favorite phrases.

Tracy

On 8/20/08, Sherlock, Ric <R.G.Sherlock at massey.ac.nz> wrote:
> >From www.jsoftware.com/help/dictionary/dictf.htm I read that a conjunction with noun or verb produces an adverb.
>
> The examples given are:
>   each=: &.>
> which I'm pretty sure I understand and
>   bc=: <"    NB. boxcells
> which I found enlightening
>   0 bc i.3
> +-+-+-+
> |0|1|2|
> +-+-+-+
>
> I know an adverb alters the meaning of the verb to its left to create a new verb. I interpret this last example to be showing that adverbs also alter the noun to its left to create a new verb. This led me to:
>   2(&^) 3  NB. Adverb (&^) applied to noun 2 gives the verb "2-to-the-power"
> 8
>   2(^&) 3  NB. Adverb (^&) applied to the noun 2 gives the verb "square"
> 9
>
> However I wasn't able to track down anything in the dictionary that states that explicitly. I looked on the following pages:
> www.jsoftware.com/help/dictionary/intro03.htm
> www.jsoftware.com/help/dictionary/intro15.htm
> www.jsoftware.com/help/dictionary/dict2.htm
> www.jsoftware.com/help/dictionary/dictb.htm
> www.jsoftware.com/help/dictionary/dictc.htm
> www.jsoftware.com/help/dictionary/dictf.htm
>
> The closest I got was on <www.jsoftware.com/help/dictionary/dict2.htm> were it states that:
>
> "An adverb acts on a single noun or verb to its left."
>
> and then gives an example of an adverb acting on a verb to create a derived verb. And on <www.jsoftware.com/help/dictionary/dictc.htm> where it states that:
>
> "Conjunctions and adverbs apply to noun or verb arguments; a conjunction
>   may produce as many as four distinct classes of results."
>
> These tells me that an adverb can apply to a noun as well as a verb, but don't tell me what the result is.
>
> Can anyone confirm or correct my interpretation?
> Can you point me to a dictionary reference?
>
> Perhaps this is basic grammar? If so, the only poor excuse I can offer is having been educated at a time where teaching grammar was deemed not important!
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