The proposal for L:_2 leaves boxes that are less than 2 levels down
unchanged. $&.>&.> applies $ somewhere in every branch. That's why I
said 'akin to' rather than 'equivalent to'.
The Dictionary gives a formal definition of negative rank. That's not a
description. When the tree has irregular shape, what the Dictionary
definition means defies description (that's a way of saying I haven't
been able to craft a description). It's easy to say what my proposed
version does: applies u n levels down, and leaves nodes less than n
levels down unchanged.
Henry Rich
On 7/29/2018 2:46 PM, Jose Mario Quintana wrote:
< L:_2 in the new definition operates two levels down, akin to &.>&.> .
I guess L:_1 would be equivalent to &.>. However, L:_2 would be only
similar to &.>&.> because, for example,
$&.>&.> t
┌──┬───────┐
│┌┐│┌─┬─┬─┐│
│││││3│2│2││
│└┘│└─┴─┴─┘│
└──┴───────┘
does not agree with the result of $L:_2 t shown in that page (if that is
what you really meant to write there), and so forth.
What it does in the old definition defies simple description.
For the current monadic case, there is an equivalence, according to the DoJ,
Negative values are complementary: u L:(-r) y ↔ u L:(0>.(L.y)-r) y
Is there a similar monadic description for your proposed L:? (I am trying
to understand your proposal better).
On Sun, Jul 29, 2018 at 9:55 AM, Henry Rich <[email protected]> wrote:
I should have phrased my question as, Has anyone used negative level
besides _1?
L:_1 always means 'open one boxing level' in either definition and differs
from &.> only in that an open argument is passed unchanged to the opened
boxes of the other. To get that effect with the new definition you would
use a level of 0 for the open argument: L:0 _1.
L:_2 in the new definition operates two levels down, akin to &.>&.> .
What it does in the old definition defies simple description.
Henry Rich
On 7/28/2018 7:11 PM, Jose Mario Quintana wrote:
I have, at least, produced code which includes L:_1 in a context in which
it is not equivalent to &.>.
Have you considered to get what you want without potentially breaking
existing code (e.g., giving meaning to imaginary whole numbers for the
right argument of L:)?
(It seems that you wrote L" instead of L: a couple of times in the
description of your proposal.)
On Fri, Jul 27, 2018 at 3:29 PM, Henry Rich <[email protected]> wrote:
I think negative level is wrongly defined. (u L:(-r) y) applies u at
level ((L. y) -r), which measures from the bottom of the tree. What I
want
is a form that applies u two levels down, say, which I can't get now. I
propose to change L: to do what I want.
Has anyone found a use for L:(-r) using the current definition?
My proposed change is described at https://code.jsoftware.com/wik
i/System/Interpreter/Requests#Change_definition_of_negative_
level_.28strawman.29
Henry Rich
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