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Read the project’s introduction
Arraymancer - A n-dimensional tensor (ndarray) library.
Arraymancer is a tensor (N-dimensional array) project in Nim. The main focus is providing a fast and ergonomic CPU, Cuda and OpenCL ndarray library on which to build a scientific computing ecosystem.
The library is inspired by Numpy and PyTorch and targets the following use-cases:
N-dimensional arrays (tensors) for numerical computing
machine learning algorithms (as in Scikit-learn: least squares solvers, PCA and dimensionality reduction, classifiers, regressors and clustering algorithms, cross-validation).
deep learning
The ndarray component can be used without the machine learning and deep learning component.
It can also use the OpenMP, Cuda or OpenCL backends.
Note: While Nim is compiled and does not offer an interactive REPL yet (like Jupyter), it allows much faster prototyping than C++ due to extremely fast compilation times. Arraymancer compiles in about 5 seconds on my dual-core MacBook.
Reminder of supported compilation flags:
-d:release: Nim release mode (no stacktraces and debugging information)
-d:danger: No runtime checks like array bound checking
-d:blas=blaslibname: Customize the BLAS library used by Arraymancer. By default (i.e. if you don't define this setting) Arraymancer will try to automatically find a BLAS library (e.g. blas.so/blas.dll or libopenblas.dll) on your path. You should only set this setting if for some reason you want to use a specific BLAS library. See nimblas for further information
-d:lapack=lapacklibname: Customize the LAPACK library used by Arraymancer. By default (i.e. if you don't define this setting) Arraymancer will try to automatically find a LAPACK library (e.g. lapack.so/lapack.dll or libopenblas.dll) on your path. You should only set this setting if for some reason you want to use a specific LAPACK library. See nimlapack for further information
-d:openmp: Multithreaded compilation
-d:mkl: Deprecated flag which forces the use of MKL. Implies -d:openmp. Use -d:blas=mkl -d:lapack=mkl instead, but only if you want to force Arraymancer to use MKL, instead of looking for the available BLAS / LAPACK libraries
-d:openblas: Deprecated flag which forces the use of OpenBLAS. Use -d:blas=openblas -d:lapack=openblas instead, but only if you want to force Arraymancer to use OpenBLAS, instead of looking for the available BLAS / LAPACK libraries
-d:cuda: Build with Cuda support
-d:cudnn: Build with CuDNN support, implies -d:cuda
-d:avx512: Build with AVX512 support by supplying the -mavx512dq flag
to gcc / clang. Without this flag the resulting binary does not use AVX512
even on CPUs that support it. Setting this flag, however, makes the binary
incompatible with CPUs that do not support AVX512. See the comments in #505
for a discussion (from v0.7.9)
You might want to tune library paths in nim.cfg after installation for OpenBLAS, MKL and Cuda compilation.
The current defaults should work on Mac and Linux; and on Windows after downloading libopenblas.dll or another
BLAS / LAPACK DLL (see the Installation section for more information) and copying it into a folder
in your path or into the compilation output folder.
Show me some code
The Arraymancer tutorial is available here.
Here is a preview of Arraymancer syntax.
Tensor creation and slicing
import math, arraymancer
const
x = @[1, 2, 3, 4, 5]
y = @[1, 2, 3, 4, 5]
var
vandermonde = newSeq[seq[int]]()
row: seq[int]
for i, xx in x:
row = newSeq[int]()
vandermonde.add(row)
for j, yy in y:
vandermonde[i].add(xx^yy)
let foo = vandermonde.toTensor()
echo foo
# Tensor[system.int] of shape "[5, 5]" on backend "Cpu"
# |1 1 1 1 1|
# |2 4 8 16 32|
# |3 9 27 81 243|
# |4 16 64 256 1024|
# |5 25 125 625 3125|
echo foo[1..2, 3..4] # slice
# Tensor[system.int] of shape "[2, 2]" on backend "Cpu"
# |16 32|
# |81 243|
echo foo[_|-1, _] # reverse the order of the rows
# Tensor[int] of shape "[5, 5]" on backend "Cpu"
# |5 25 125 625 3125|
# |4 16 64 256 1024|
# |3 9 27 81 243|
# |2 4 8 16 32|
# |1 1 1 1 1|
Reshaping and concatenation
import arraymancer, sequtils
let a = toSeq(1..4).toTensor.reshape(2,2)
let b = toSeq(5..8).toTensor.reshape(2,2)
let c = toSeq(11..16).toTensor
let c0 = c.reshape(3,2)
let c1 = c.reshape(2,3)
echo concat(a,b,c0, axis = 0)
# Tensor[system.int] of shape "[7, 2]" on backend "Cpu"
# |1 2|
# |3 4|
# |5 6|
# |7 8|
# |11 12|
# |13 14|
# |15 16|
echo concat(a,b,c1, axis = 1)
# Tensor[system.int] of shape "[2, 7]" on backend "Cpu"
# |1 2 5 6 11 12 13|
# |3 4 7 8 14 15 16|
Broadcasting
Image from Scipy
import arraymancer
let j = [0, 10, 20, 30].toTensor.reshape(4,1)
let k = [0, 1, 2].toTensor.reshape(1,3)
echo j +. k
# Tensor[system.int] of shape "[4, 3]" on backend "Cpu"
# |0 1 2|
# |10 11 12|
# |20 21 22|
# |30 31 32|
A simple two layers neural network
From example 3.
import arraymancer, strformat
discard """
A fully-connected ReLU network with one hidden layer, trained to predict y from x
by minimizing squared Euclidean distance.
"""
# ##################################################################
# Environment variables
# N is batch size; D_in is input dimension;
# H is hidden dimension; D_out is output dimension.
let (N, D_in, H, D_out) = (64, 1000, 100, 10)
# Create the autograd context that will hold the computational graph
let ctx = newContext Tensor[float32]
# Create random Tensors to hold inputs and outputs, and wrap them in Variables.
let
x = ctx.variable(randomTensor[float32](N, D_in, 1'f32))
y = randomTensor[float32](N, D_out, 1'f32)
# ##################################################################
# Define the model
network TwoLayersNet:
lay
Read the full README on GitHub