Is monadic # what you're looking for?
mask # chars
BEG
HH PackRat <[email protected]> wrote:
> Hello, all!
>
> I have a list of characters and a boolean list of 1s and 0s. I
> thought that I could use the boolean list as a "mask" to choose
> characters by using "and" (*.). But the definition in NuVoc basically
> states that it can only be used with numbers (no literals).
>
> Here's an example of the kind of thing I'd like to be able to do:
>
> chars=. 'ABCDEFGHIJKLM'
> mask=. 0 1 0 0 1 0 1 0 0 0 0 0 0 [boolean values]
>
> mask2=. 0 1 0 0 4 0 6 0 0 0 0 0 0 [positions of boolean values]
>
> I thought that I could do something like chars *. mask to get the
> result BEG. That doesn't work nor does converting the mask to
> position numbers (mask2) work. So how *can* I mask the characters?
> I'd be interested in knowing both the "pure" boolean kind of approach
> (1s and 0s only) as well as a positional approach that I can use with
> amending.
>
> My ultimate goal is actually to amend the masked characters to be a
> different character(s). I hope I've given enough information. (The
> example, of course, is completely "fake", but I hope it gives the idea
> of what I'm trying to do.)
>
> Thanks for any help!
>
> Harvey
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