====== Windows 10 に NVIDIA CUDA をインストールする方法 ======

===== CUDA Toolkit 10.1 Update 1 のダウンロード =====
[[https://developer.nvidia.com/cuda-toolkit|CUDA Toolkit | NVIDIA Developer]] より [[https://developer.nvidia.com/compute/cuda/10.1/Prod/local_installers/cuda_10.1.168_425.25_win10.exe|CUDA Toolkit 10.1 Update 1]] をダウンロードする。\\
<code>
Operating System: Windows
Architecture: x86_64
Version: 10
Installer Type: exe (local)
</code>

===== CUDA Toolkit のインストール =====
インストーラーの「次へ」をクリックしてインストールを行う。オプションはデフォルトのまま。\\
===== トラブルシューティング =====

==== pip install CuPy で WARNING: nvcc not in path が表示される ====
<code>
Collecting CuPy
  Downloading https://files.pythonhosted.org/packages/fb/18/a8c5f594d6fc70d70e53c7847eabc9b922c037b3b7dff4af89a499217d42/cupy-6.1.0.tar.gz (3.1MB)
     |████████████████████████████████| 3.1MB 1.3MB/s
    ERROR: Complete output from command python setup.py egg_info:
    ERROR: Options: {'package_name': 'cupy', 'long_description': None, 'wheel_libs': [], 'wheel_includes': [], 'no_rpath': False, 'profile': False, 'linetrace': False, 'annotate': False, 'no_cuda': False}
    **************************************************
    *** WARNING: nvcc not in path.
    *** WARNING: Please set path to nvcc.
    **************************************************

    -------- Configuring Module: cuda --------
    a.cpp
    C:\Users\tomoyan\AppData\Local\Temp\tmplz2aff47\a.cpp(1): fatal error C1083: include ファイルを開けません。'cublas_v2.h':No such file or directory
    command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\Preview\\VC\\Tools\\MSVC\\14.20.27305\\bin\\HostX86\\x64\\cl.exe' failed with exit status 2

    ************************************************************
    * CuPy Configuration Summary                               *
    ************************************************************

    Build Environment:
      Include directories: []
      Library directories: []
      nvcc command       : (not found)

    Environment Variables:
      CFLAGS          : (none)
      LDFLAGS         : (none)
      LIBRARY_PATH    : (none)
      CUDA_PATH       : (none)
      NVTOOLSEXT_PATH : (none)
      NVCC            : (none)

    Modules:
      cuda      : No
        -> Include files not found: ['cublas_v2.h', 'cuda.h', 'cuda_profiler_api.h', 'cuda_runtime.h', 'cufft.h', 'curand.h', 'cusparse.h', 'nvrtc.h']
        -> Check your CFLAGS environment variable.

    ERROR: CUDA could not be found on your system.
    Please refer to the Installation Guide for details:
    https://docs-cupy.chainer.org/en/stable/install.html

    ************************************************************

    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "C:\Users\tomoyan\AppData\Local\Temp\pip-install-ny1cq3om\CuPy\setup.py", line 120, in <module>
        ext_modules = cupy_setup_build.get_ext_modules()
      File "C:\Users\tomoyan\AppData\Local\Temp\pip-install-ny1cq3om\CuPy\cupy_setup_build.py", line 632, in get_ext_modules
        extensions = make_extensions(arg_options, compiler, use_cython)
      File "C:\Users\tomoyan\AppData\Local\Temp\pip-install-ny1cq3om\CuPy\cupy_setup_build.py", line 387, in make_extensions
        raise Exception('Your CUDA environment is invalid. '
    Exception: Your CUDA environment is invalid. Please check above error log.
    ----------------------------------------
ERROR: Command "python setup.py egg_info" failed with error code 1 in C:\Users\tomoyan\AppData\Local\Temp\pip-install-ny1cq3om\CuPy\
</code>
これは CUDA Toolkit をインストールすると改善される。\\
CUDA Toolkit をインストールしてから CuPy のインストールを行う。\\
<code>
>pip install CuPy
Collecting CuPy
  Using cached https://files.pythonhosted.org/packages/fb/18/a8c5f594d6fc70d70e53c7847eabc9b922c037b3b7dff4af89a499217d42/cupy-6.1.0.tar.gz
Requirement already satisfied: numpy>=1.9.0 in c:\python37\lib\site-packages (from CuPy) (1.16.4)
Requirement already satisfied: six>=1.9.0 in c:\python37\lib\site-packages (from CuPy) (1.12.0)
Collecting fastrlock>=0.3 (from CuPy)
  Downloading https://files.pythonhosted.org/packages/8f/ff/6777b85fdbc6efd572a2b713e044c29f5f01ca8b1c74f8d94b427bac60c3/fastrlock-0.4.tar.gz (47kB)
     |████████████████████████████████| 51kB 1.1MB/s
Installing collected packages: fastrlock, CuPy
  Running setup.py install for fastrlock ... done
  Running setup.py install for CuPy ... done
Successfully installed CuPy-6.1.0 fastrlock-0.4
</code>

===== 参考文献 =====
[[https://qiita.com/mash0510/items/fcc8fe717de4bcee90b2|Windows10にChainer+CUDA 8.0をインストール - Qiita]]\\