I'm trying to write a test for a graphical component in Dyalog APL which will simulate button clicks which open new windows and keystrokes for filling in form fields. My first approach was to simply write a sequence of ⎕NQ statements for enqueuing events:
⎕NQ '#.foo.barButton' 'Select' ⍝ open...
I'm studying APL from here.
Why am I getting this syntax error?
'computer' [ 1 2 3 ] ← 'COM'
SYNTAX ERROR
'computer'[1 2 3]←'COM'
^
But if I save 'computer' in a variable I don't get the error:
T ← 'computer'
T
computer
T[1 2 3] ← 'COM'
T
COMputer
Wh...
{10=(¯1↑⍵)+10|(⌈/+/@(n-1)⊢⍵)+⌈/3×+/@(n←2×⍳6)⊢⍵} (takes a vector of digits as input) any clear golfs you guys can see here? I'm still checking if all the parenthesis are necessary
{10=¯1↑⍵+⍨10|⌈/+/@(n-1)⊢⍵+⌈/3×+/@(n←2×⍳6)⊢⍵} removed the redundant parens
@dzaima so, your expression effectively does inner product with (1+2)(1-2)(1+2)(1-2)... ←→ 3 ¯1 3 ¯1... ←→ 3 9 3 9... (mod 10) ←→ 3 × (1 3 1 3...). we're only interested when that is 0 (mod 10), so that's why it's correct
in other words, you outgolfed me :) i don't think the expression can be shrunk any further
okay guys, so: If I have a function f and an argument ⍵, how do I run f⍵ times, feeding the result of f onto itself? I'm trying to use ⍣ and failing miserably.
@Adám can you give me a lil' hand here? I need to repeat the inner function from {0=⍵:0⋄{4 3 3 5 4 4 3 5 5 4[⍎¨⍕⍵]}}<arg>arg times, starting at 0 and feeding the result of the inner function for the next iteration (basically f(f...(f(0))) )
@Cowsquack my in function is horrible and I needed to convert all rectangles to that format so they would register correctly no matter which direction the rectangle was made (done by the sort function)
@Cowsquack It's not that any of those operations you gave are inherently inefficient, it's about how they map to the machine in the interpreter, and how easy or hard it is to convert an expression to good machine code. Sometimes, there's a very hard line that you can draw (such as the use of Each when you don't need it), but other times that's more subtle.
The more you're willing to let the system work on your code (through magic compilation or super-compilation) the more your code will suddenly become efficient, but the less you'll be able to predict whether it will do so without vast amounts of additional knowledge.
Thus, the stylistic metric is for simpler, more direct code, since that's what the interpreter can make fast.
It's also easier to read.
Understanding why it is slow or fast is a simple matter of understanding how the primitives map to the hardware and memory.
@dzaima looks like the color is stored as protected fields, which I don't have access to. Probably not worth it making my own storage for the fill color, but I'll switch it to G.fill←
Well, I meant the actual algorithm, not so much the golfing. Checking trigrams was about what I was zeroing in on anyways before I looked at the solutions.
I'm studying APL from here.
Why am I getting this syntax error?
'computer' [ 1 2 3 ] ← 'COM'
SYNTAX ERROR
'computer'[1 2 3]←'COM'
^
But if I save 'computer' in a variable I don't get the error:
T ← 'computer'
T
computer
T[1 2 3] ← 'COM'
T
COMputer
Wh...
