16.01.2020 0:42, Henry Rich:
0 *:@[ F:. ([ (1 Z: 25&=)) 3 1 4 6 5 7 8 9
9 1 16 36 25
Suggestion for improving Fold are welcomed.
Great! Thank you for your hard work!
You are using trick with postfiltering output result
1. I found the bug:
0 *:@[ F:. (] [ 1&Z:)&:(25&=) 3 1 4 6 5 7 8 9
0 0 0 0 0 0 0 0
Expecting:
0 0 0 0 1
2. In ideal case I expecting only one result from my function: 0 or 1.
I can realize it using your approach with +/
But this is waste computations.
I hope F.. is decision for skipping unnecessary intermediate results.
But I see same bug:
0 (1&Z: ] ])&:((25&=)@*:@[) F.. ] 3 1 4 5 8 7 8 9
0
Expected:
1
3. About suggestion. For my mind very strange and hard current argument
ordering for u in Fold.
IMHO it's contintuitive.
d =: dyad : 0
echo x ; y
0
)
0 d F:. ] 1 2 3
0 d F:. ] 1 2 3
┌─┬─┐
│1│0│
└─┴─┘
┌─┬─┐
│2│0│
└─┴─┘
┌─┬─┐
│3│0│
└─┴─┘
0 0 0
For my more clear order:
x - ini (previsious) value
y - value from array
┌─┬─┐
│0│1│
└─┴─┘
┌─┬─┐
│0│2│
└─┴─┘
┌─┬─┐
│0│3│
└─┴─┘
0 0 0
Thank you!
Sergey
Henry Rich
On 1/15/2020 2:58 PM, 'Sergey Kamenev' via Programming wrote:
Hi!
I need test function f on array x1 x2 ... xn
If f(x) = 0 then no need test another member of array.
I don't understand how write this code loopless.
Main thing: I would avoid of waste computation of f(x) if f(x) = C found.
I think about Fold but I see only ugly decision with using global variables.
Example code for rewriting:
NB. Vector with test values
a =: 1 + i. y
f =: *:
example =: monad : 0
for_i. a do.
if. 25 = f i do.
i return.
end.
0
end.
)
example a
Nice day!
Sergey
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