A tensor (multidimensional array) library for Nim

vector, matrix, array, ndarray, multidimensional-array, linear-algebra, tensor, autograd, automatic-differentiation, cuda, cudnn, deep-learning, gpgpu, gpu-computing, high-performance-computing, iot, machine-learning, matrix-library, multidimensional-arrays, neural-networks, nim, opencl, openmp, parallel-computing
nimble install arraymancer



A tensor (N-dimensional array) project. Focus on machine learning, deep learning and numerical computing.

A tensor supports arbitrary types (floats, strings, objects ...).

EXPERIMENTAL: API may change and break.


The automatic backpropagation library Nim-RMAD needs to be generalized to vectors and matrices, 3D, 4D, 5D tensors for deep learning.

Unfortunately, attempts to use linalg's vector and matrix types were unsuccessful. Support for 3D+ tensors would also need more work.

This library aims to provided an efficient tensor/ndarray type. Focus will be on numerical computation (BLAS) and GPU support. The library will be flexible enough to represent arbitrary N-dimensional Arrays, especially for NLP word vectors.

Current status

EXPERIMENTAL: Arraymancer may summon Ragnarok and cause the heat death of the Universe.

Arraymancer's tensors currently support the following:

  • Wrapping any type: string, floats, object

  • Getting and setting value at a specific index (Caveat: negative indices support needs work)

  • Creating a tensor from deep nested sequences

  • Universal functions from Nim math module: cos, ln, sqrt... will work element-wise

  • Creating your own universal functions with makeUniversal, makeUniversalLocal and fmap.

    fmap can even be used on functions with input/ouput of different types.

  • Optimized Linear Algebra through BLAS (via nimblas)

    For now only Matrix to Matrix multiplication is available, multiplication and addition for Vector-Vector, Matrix-Vector and Matrix-Matrix are coming very soon.

Check syntax examples in the test folder.

Not prioritized

The following Numpy-like functionality:

  • slicing,
  • iterating,
  • assigning,
  • statistics (mean, median, stddev ...)

will be added on an as-needed basis.