Apple Array System
Some cases are not implemented. This is provided as an artefact.
See Apple by Example for a demonstration of capabilities.
The compiler will bail out with arcane error messages rather than produce an incorrect result, except that the Python/R extension modules do not enforce type safety and thus may mysteriously segfault or produce unpredictable corrupt results.
Spilling (during register allocation) is not implemented for Arm. Also floating-point registers aren't spilled on x86.
Compiler-As-a-Library
Rather than an environment-based interpreter or a compiler invoked on the command line and generating object files, one calls a library function which returns assembly or machine code from a source string.
Thus the same implementation can be used interpreted, compiled, or called from another language.
> [((+)/x)%ℝ(:x)]\`7 (frange 1 10 10) Arr (4) [4.0, 5.0, 6.0, 7.0]
>>> import apple >>> import numpy as np >>> sliding_mean=apple.jit('([((+)/x)%(ℝ(:x))]\`7)') >>> apple.f(sliding_mean,np.arange(0,10,dtype=np.float64)) array([3., 4., 5., 6.])
> source("R/apple.R") > sliding_mean<-jit("([((+)/x)%ℝ(:x)]\\`7)") > run(sliding_mean,seq(0,10,1.0)) [1] 3 4 5 6 7
The JIT'ed moving average in Apple happens to be faster than the rolling mean from the zoo package.
Dimension As a Functor
This is based on J (and APL?). Looping is replaced by functoriality (rerank).
To supply a zero-cells (scalars) as the first argument to ⊲ (cons) and 1-cells as the second:
(⊲)`{0,1}
We can further specify that the cells should be selected along some axis, e.g. to get vector-matrix multiplication:
λA.λx. { dot ⇐ [(+)/((*)`x y)]; (dot x)`{1∘[2]} (A::Arr (i`Cons`j`Cons`Nil) float) }
The 2 means "iterate over the second axis" i.e. columns.
Installation
Use ghcup to install cabal and GHC. Then:
make install
to install arepl (the REPL).
Run
make sudo make install-lib
To install the shared library.
Python
To install the Python module:
make install-py
R
Install libappler.so on your system like so:
make -C Rc sudo make install-r
Then:
source("R/apple.R")
to access the functions.
Documentation
Type \l in the REPL to show the reference card:
> \l Λ scan √ sqrt ⋉ max ⋊ min ⍳ integer range ⌊ floor ℯ exp ⨳ {m,n} convolve \~ successive application \`n dyadic infix _. log 'n map ` zip `{i,j∘[k,l]} rank 𝒻 range (real) 𝜋 pi _ negate : size 𝓉 dimension }.? last ->n select ** power gen. generate 𝓕 fibonacci re: repeat }. typesafe last ⊲ cons ⊳ snoc ^: iterate %. matmul ⊗ outer product |: transpose {.? head {. typesafe head }.? last }: typesafe init ⟨z,w⟩ array literal ?p,.e1,.e2 conditional ...
Enter :help in REPL:
> :help :help, :h Show this help :ty <expression> Display the type of an expression ...
