The APL Orchard

4:35 AM

Dealing with so much Java and Groovy at work. Really tempted to casually add in Dzaima APL.

4:56 AM

@user1782004 Hi Alexea Marie Nieves, if you want to participate here, please email access@apl.chat

Q: Split string on first occurrence of each character

5:09 AM

@preaburn What error do you get from ⎕FTIE?

Who can find (or brute-force!) the 3-char solution to this?

Related. Given a printable ASCII string, split it into a list of non-empty strings with a new sub-string beginning every time a character, which has not previously been seen in the same case, occurs. Examples "mississippi" → ["m","i","ssissi","ppi"] "P P & C G" → ["P"," P ","& ","C ","G"] "A...

6:02 AM

Can't find the link for syntax here. There was a cute hack for making spoilers.

@Adám spoiler

Aiden Chow

@B.Wilson i think u do [spoiler](https://google.com "spoiler text")

@B.Wilson You don't have a link to apl.wiki/APL_Orchard on the right? it is there under Basic_formatting.

@AidenChow Finally got there :P There was actually about a 5s delay until the link rendered, where it showed literally, so the last two deletions are even more spurious than the first two!

@AidenChow That makes a link rather than a spoiler.

Aiden Chow

@Adám u r supposed to hover on top of the link to see the spoiler text

6:09 AM

yes.

ofc, that means touch devices have an accessibility problem...

@Adám I do but am just dumb. Was looking for an SE link.

preaburn

I get a value error because it doesn't allow me to tie the file. I am not totally clear on the reason but it has to do with the fact that a new workspace is called everytime a page load event occurs.

@preaburn I don't follow. If you cannot tie the file, ⎕FTIE should error, but not with a value error.

5 hours later…

11:47 AM

@Adám What time was the Quest today?

15:00 UTC, i.e. in 3 hours and 11 minutes.

2 hours later…

1:22 PM

huh, why the time change?

Because it clashes with my schedule every Friday.

2:02 PM

@Adám BTW, the APL Quest banner announcement still seems like it's set for the old time.

2:13 PM

@B.Wilson oops.

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@Richard @att @BrianBED user1175060 @lyxal @user287218 @user287218 @user19874054 @user19874054 @user19758417 @user19758417 @user1275760 @user1275760 consider signing up for reminders at the new time.

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LdBeth

2:31 PM

in 30 mins

2:52 PM

noice the time change works better with my schedule too

Welcome to APL Quest 2018-9! Today's quest is Earlier, Later, or the Same?:

> Write an APL expression that given left and right arguments of Y M D h m s f vector timestamps returns a ¯1, 1, or 0 if the left argument represents a time that is respectively, earlier than, later than, or simultaneous with the right argument.

I wsa very proud of my solution, until you pointed me to APLchart :)

{⍺≡⍵:0 ⋄ -/⍋⍺ ⍵}

That is nice, but you can combine the guard expression and the main expression, the APL way.

oh, that makes sense - i had {×-/¯1 1⎕dt ⍺ ⍵}

You don't need to specify ¯1 — that's the default for vectors.

rabbitgrowth

3:02 PM

I had ⊃0~⍨×⍤-

That's beautiful.

I had (>-<)⍥(1⎕DT⊂)

@rabbitgrowth wow that ~ trick is nice

And using ⊃ to coerce a new 0 if they are all equal.

@Adám really? That seems to have domain error in tests:×-/ 1⎕dt ⍺ ⍵ caused DOMAIN ERROR with (3345 4 16 14 11 12) as left argument and (4337 2 12 17 54 7) as right argument

~~time to rework one of my problem solving competition entries~~

3:04 PM

Shh!

@Silas I get the same error if I have the ¯1 there.

huh, with the ¯1 says passed basic tests but not (7⍴0) as arguments

rabbitgrowth

I had ⊃0,⍨0~⍨×⍤- at first, then realized the 0,⍨ could be dropped

I'm at a loss here. I get "should have returned" with {-/1⎕dt ⍺ ⍵} but a domain error when inserting ×. How can × domain error on a number or -/ return a non-number‽

Shh!

@Adám how? You cannot distinguish between two same entries and two following up ones

{(⍺≡⍵)×-/⍋⍺ ⍵}

3:10 PM

ah ok :)

Or train it to be ≡×{-/⍋⍺ ⍵}

Here's a fun one: ×-⍥(1000∘⊥)

@Adám how precise is this one? Will give huge numbers

Ah yes, we'll need ⎕FR←1287 for it.

I also tried to make {-/⍋⍺ ⍵} tacit.
Probably not usefull but got stuck at (-/⍒,⍥⊂)

You can do -/⍤⍒⍤,⍥⊂ but…

Anyone up for an industrial solution?

3:24 PM

yes

{⎕USING←'System' ⋄ DateTime.Compare{⎕NEW DateTime ⍵}¨⍺⍵}

Won't work online because the Linux server has no .NET installed :-)

dyalog apl can access .net?

Yes, it was on Microsoft's official list of .NET programming languages back when .NET was new.

huh