It's no crime to make u explicit, and use a global to hold the
intermediate results.
Henry Rich
On 12/2/2014 9:09 PM, Jon Hough wrote:
I do not think updating y is what I need in this case.In pseudocode, an example
is
x = 3; //just some start value for xy; //some arrayfor (i = 0; i < max; i+= 4){
x = myVerb(x, y[i], y[i+1], y[i+2], y[i+3]); //my verb is equivalent(~ish) to
verb u.}
return x;
So I thought using u\ would be a good way to do the forloop. The problem, of
course, is that the previous iteration's result of myVerb is the next
iterations myVerb parameter.
I'm not wedded to the idea of using u\, and I am beginning to wonder if it is
completely inappropriate for doing this.
Date: Wed, 3 Dec 2014 01:27:39 +0000
From: [email protected]
To: [email protected]
Subject: Re: [Jprogramming] Modifying x inside Infix
The argument to 4 u\ y will be entirely y, and u is monadic.
you can do something like this though:
2 (3&+)\ i.5
3 4
4 5
5 6
6 7
If you can change your spec to "updating y" on every iteration, and you want to
apply to:
x1 u (x2 u y)
then you can make a table where x1, x2 and y are the 3 rows, and then call with
u/. You can search for boxscan in archives for method where x and y are not
the same shape. This is generally preferable to trying to keep a side effect
between calls (so you don't need to worry about initializing it)
________________________________
From: Jon Hough <[email protected]>
To: "[email protected]" <[email protected]>
Sent: Tuesday, December 2, 2014 7:58 PM
Subject: [Jprogramming] Modifying x inside Infix
If y is a list and I have a dyadic verb u, which I want to apply to every 4
items of y I can do
x ( 4 u \) y
and this will apply x u to every 4 items.
But I want to continually update x every iteration. So after doing x u y to the
first 4 items, x becomes the result,
i.e. x =: x u y
How do I do this for all the list?
I tried things like
result =: leftArg ( 4 (leftArg =:) u \ )rightArg
but I can't get the correct syntax (assuming there is a way to do this).
(I hope my explanation made sense.)
Thanks.
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