This is a collection of idioms and small programs in APL, J, BQN, Julia, R and NumPy.
There are several sites that do these kinds of comparisons:
| Language | Main Website | Help / Docs | Online REPL | |
|---|---|---|---|---|
| 💚 | Dyalog APL | dyalog.com | Dyalog Help | TryAPL |
| 💚 | J | jsoftware.com | J NuVoc | J Playground |
| 💚 | BQN | mlochbaum.github.io/BQN | BQN Docs | BQNPAD |
| 💚 | Q | code.kx.com/q | Q Ref | 🚫 |
| 💙 | Julia | julialang.org | Julia Docs | Replit |
| 💙 | NumPy* | numpy.org | NumPy Docs | Replit |
| 💙 | R | r-project.org | R Docs | JDoodle |
| 💜 | Nial | nial-array-language.org | Nial Dictionary | TIO |
| 💜 | Futhark | futhark-lang.org | Futhark Docs | 🚫 |
| 💜 | SaC | sac-home.org | SaC Docs | 🚫 |
* Library, not an actual language
- 💚 Main (APL-Family) Array Languages
- 💙 Main (Non-APL-Family) Array Languages
- 💜 Fringe Array Languages
- REPL
- Index Base
- Length of Array (Leading Axis)
- Shape of Array
- Number of Elements in Array
| 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|
| APL | 🟢 | 1 (or ⎕IO) |
≢ |
⍴ |
×/⍴ |
| J | 🟢 | 0 | # |
$ |
*/@$ |
| BQN | 🟢 | 0 | ≠ |
≢ |
×´≢ |
| Q | 🟡 | 0 | count |
🚫 | count raze |
| Julia | 🟢 | 1 | size(a, 1) |
size(a) |
length(a) |
| NumPy | 🟢 | 0 | len(a) |
a.shape |
a.size |
| R | 🟢 | 1 | dim(a)[1] |
dim(a) |
length(a) |
| Nial | 🟡 | 0 | first shape |
shape |
tally |
| Futhark | 🟡 | 0 | length |
🚫 | flatten |> length |
| SaC | 🚫 | 0 | shape(a)[0] |
shape(a) |
prod(shape(a)) |
🟡 Means the REPL has limitations
- Q REPL has no HOME, END, or any arrows (CTRL or not)
- Nial REPL has no CTRL left or right arrow
- Futhark REPL has no HOME, END, or DEL
If you are using Q, Nial, Futhark or other languages with REPL limitations, you can get around this by invoking with rlwrap. On Linux using the Q REPL:
sudo apt install rlwrap
rlwrap taskset -c 0 ./q