BQN–Dyalog APL dictionary

A few tables to help users of Dyalog APL (or similar) get started quickly on BQN. Here we assume ⎕ML is 1 for Dyalog.

For reading

Here are some closest equivalents in Dyalog APL for the BQN functions that don't use the same glyphs as APL. Correspondence can be approximate, and ⌽ is just used as a decorator to mean "reverse some things".

BQN	`⋆`	`√`	`∧`	`∨`	`¬`	`≠`	`<`	`>`	`≢`	`⥊`	`∾`	`≍`
Monad	`*`	`*∘(÷2)`	`[⍋]`	`[⍒]`	`~`	`≢`	`⊂`	`↑`	`⍴`	`,`	`⊃,⌿`	`↑,⍥⊂`
Dyad	`*`	`*∘÷⍨`	`∧`	`∨`	`1+-`	`≠`	`<`	`>`	`≢`	`⍴`	`⍪`	`↑,⍥⊂`

BQN	`↑`	`↓`	`↕`	`/`	`⍋`	`⍒`	`⊏`	`⊑`	`⊐`	`⊒`	`∊`	`⍷`	`⊔`
Monad	`,⍀`	`⌽,⌽⍀⌽`	`⍳`	`⍸`	`⍋`	`⍒`	`⊣⌿`	`⊃`		`…`	`≠`	`∪`	`⌸`
Dyad	`↑`	`↓`	`,⌿`	`⌿`	`⍸`	`⌽⍸⌽`	`⌷`	`⊃`	`⍳`	`…`	`∊`	`⍷`	`⌸` or `⊆`

Modifiers are a little harder. Many have equivalents in some cases, but Dyalog sometimes chooses different functionality based on whether the operand is an array. In BQN an array is always treated as a constant function.

BQN	`¨`	`⌜`	`˝`	`⎉`	`⍟`	`˜`	`∘`	`○`	`⟜`
Dyalog	`¨`	`∘.`	`⌿`	`⍤`	`⍣`	`⍨`	`⍤`	`⍥`	`∘`

In BQN ⎉ is Rank and ∘ is Atop. Dyalog's Atop (⍤) and Over (⍥) were added in version 18.0.

For writing

The tables below give approximate implementations of Dyalog primitives for the ones that aren't the same. First- and last-axis pairs are also mostly omitted. BQN just has the first-axis form, and you can get the last-axis form with ⎉1.

Functions
Glyph	Monadic	Dyadic
`*`	`⋆`
`⍟`	`⋆⁼`
`!`	Implement it yourself
`○`	Some complex exponential stuff, maybe
`~`	`¬`	`¬∘∊/⊣`
`?`	Library?
`⍲`		`¬∘∧`
`⍱`		`¬∘∨`
`⍴`	`≢`	`⥊`
`,`	`⥊`	`∾⎉1`
`⍪`	`⥊˘`	`∾`
`↑`	`>`	`↑`
`↓`	`<˘`	`↑`
`⊂`	`<`	+`⊸⊔
`⊆`	`<⍟(0<≡)`	`⊔`
`∊`	`{0=≡𝕩:⥊𝕩⋄∾⥊∇¨𝕩}`	`∊`
`⊃`	`⊑`
`⍀`		`/⁼`
`∩`		`∊/⊣`
`∪`	`⍷`	`⊣∾∊˜¬⊸/⊢`
`⍳`	`↕`	`⊐`
`⍸`	`/`	`⍋`
`⍋`	`⍋`	Give up
`⍒`	`⍒`	Give up
`≢`	`≠`	`≢`
`⍎`	To be decided
`⍕`	To be decided
`⊥`		`{+⟜(𝕨⊸×)´⌽𝕩}`
`⊤`		{𝕨\|1↓⌊∘÷`⌾⌽𝕨∾<𝕩}
`⌹`	`+˝∘×⎉1‿∞⁼` I guess
`⌷`	N/A	`⊏`

Operators
Syntax	Monadic	Dyadic
`⌿`	`¨˝`	`↕`
`⍀`	`↑` or `
`¨`	`¨`
`⍨`	`˜`
`⍣`	`⍟`
`f.g`		`f˝∘g⎉1‿∞`
`∘.f`		`f⌜`
`A∘g`	`A⊸g`
`f∘B`	`f⟜B`
`f∘g`	`f⟜g`
`f⍤B`	`f⎉B`
`f⍤g`	`f∘g`
`f⍥g`	`f○g`
`f@v`	`f⌾(v⊸⊏)`
`f⍠B`	Uh
`f⌸`	`⍷⊸⊐⊔↕∘≠`	`⍷⊸⊐⊸⊔`
`f⌺B`	`↕`
`A⌶`	`•`
`f&`	Nothing yet