Cannot use fastmat with numpy 2.1.3 on python 3.12, cannot install from source either

[3ddP]

The following problem has been experienced in WSL Ubuntu 22.04.03 LTS and WSL Ubuntu 22.04.05 LTS, with conda and with venv. The issue also occurs if numpy is installed via conda before pip installing fastmat.

• In a clean environment in which only pip install fastmat has been run, attempting to import Toeplitz from fastmat results in the following error:

Python 3.12.7 | packaged by Anaconda, Inc. | (main, Oct  4 2024, 13:27:36) [GCC 11.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import numpy as np
>>> from fastmat import Toeplitz
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/edd/anaconda3/envs/fm/lib/python3.12/site-packages/fastmat/__init__.py", line 53, in <module>
    from .Matrix import Matrix, Hermitian, Conjugate, Transpose, flags
  File "fastmat/Matrix.pyx", line 1, in init fastmat.Matrix
ValueError: numpy.dtype size changed, may indicate binary incompatibility. Expected 96 from C header, got 88 from PyObject

• Attempting to instead download the source and install via pip install . as per the instructions in the README results in a huge number of warnings and errors. A small excerpt is included at the end of the issue.

Error compiling Cython file:
      ------------------------------------------------------------
      ...


      ################################################## type handling

      cdef INFO_TYPE_s typeInfo[NUM_TYPES]
      cdef ftype typeSelection[<int> np.NPY_NTYPES]
                                       ^
      ------------------------------------------------------------

      fastmat/core/types.pxd:161:33: Not allowed in a constant expression

      Error compiling Cython file:
      ------------------------------------------------------------
      ...


      ################################################## type handling

      cdef INFO_TYPE_s typeInfo[NUM_TYPES]
      cdef ftype typeSelection[<int> np.NPY_NTYPES]
                              ^
      ------------------------------------------------------------

      fastmat/core/types.pxd:161:24: Variable type 'ftype []' is incomplete
      Traceback (most recent call last):
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1345, in cythonize_one_helper
          return cythonize_one(*m)
                 ^^^^^^^^^^^^^^^^^
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1321, in cythonize_one
          raise CompileError(None, pyx_file)
      Cython.Compiler.Errors.CompileError: fastmat/BlockDiag.pyx
      Traceback (most recent call last):
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1345, in cythonize_one_helper
          return cythonize_one(*m)
                 ^^^^^^^^^^^^^^^^^
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1321, in cythonize_one
          raise CompileError(None, pyx_file)
      Cython.Compiler.Errors.CompileError: fastmat/Circulant.pyx
      Traceback (most recent call last):
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1345, in cythonize_one_helper
          return cythonize_one(*m)
                 ^^^^^^^^^^^^^^^^^
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1321, in cythonize_one
          raise CompileError(None, pyx_file)
      Cython.Compiler.Errors.CompileError: fastmat/Diag.pyx
      Traceback (most recent call last):
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1345, in cythonize_one_helper
          return cythonize_one(*m)
                 ^^^^^^^^^^^^^^^^^
        File "/home/edd/fastmat-stable/.eggs/Cython-3.0.11-py3.12-linux-x86_64.egg/Cython/Build/Dependencies.py", line 1321, in cythonize_one
          raise CompileError(None, pyx_file)
      Cython.Compiler.Errors.CompileError: fastmat/Blocks.pyx