Oh, yeah.  Thanks.

I guess there is a possible improvement, but it would take some work to make sure the verbs haven't changed.


Or maybe precompute the inverse if g is name-free?

Henry


On 9/18/2016 11:41 AM, Roger Hui wrote:
If f=:g&.:h where h is a named verb, and subsequently you change h ...

On Sun, Sep 18, 2016 at 8:12 AM, Henry Rich <henryhr...@gmail.com> wrote:

Nosing around in cu.c I find

static DF1(jtundco1){DECLFG; R df1( w,atop(inv(gs),ampco(fs,gs)));}

This is the routine that executes on the verb derived from u&.:v .

What I don't understand is why the calculation of the inverse and &: and @
are not performed before the derived verb is created.  That result could be
stored in h, which would shorten this code to

static DF1(jtundco1){DECLFGH; R df1(  w,hs);}

As it is, the inverse calculation etc are performed every time the verb is
executed on data.

Can anyone show cause why this calculation should not be performed during
the execution of &.: rather than in the derived verb?

Henry

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