title: ERROR: You must give at least one requirement to install -- when running: pip install --upgrade --no-binary hdbscan
body: <p>I am trying to install hdbscan in my PC which runs Windows 10 and has installed Python 3.6.  </p>
  
  <p>My first attempt failed:</p>
  
  <pre><code>(base) C:\WINDOWS\system32&gt;pip install hdbscan --user
  Collecting hdbscan
    Using cached https://files.pythonhosted.org/packages/10/7c/1401ec61b0e7392287e045b6913206cfff050b65d869c19f7ec0f5626487/hdbscan-0.8.22.tar.gz
    Installing build dependencies ... done
    Getting requirements to build wheel ... done
      Preparing wheel metadata ... done
  Requirement already satisfied: scikit-learn&gt;=0.17 in c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages (from hdbscan) (0.19.1)
  Requirement already satisfied: joblib in c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages (from hdbscan) (0.13.2)
  Requirement already satisfied: numpy&gt;=1.16.0 in c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages (from hdbscan) (1.17.2)
  Requirement already satisfied: cython&gt;=0.27 in c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages (from hdbscan) (0.29.10)
  Requirement already satisfied: scipy&gt;=0.9 in c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages (from hdbscan) (1.2.2)
  Building wheels for collected packages: hdbscan
    Building wheel for hdbscan (PEP 517) ... error
    ERROR: Command errored out with exit status 1:
     command: 'c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\python.exe' 'c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages\pip\_vendor\pep517\_in_process.py' build_wheel 'C:\Users\Alienware\AppData\Local\Temp\tmp8ir950og'
         cwd: C:\Users\Alienware\AppData\Local\Temp\pip-install-hxifwoph\hdbscan
    Complete output (67 lines):
    running bdist_wheel
    running build
    running build_py
    creating build
    creating build\lib.win-amd64-3.6
    creating build\lib.win-amd64-3.6\hdbscan
    copying hdbscan\hdbscan_.py -&gt; build\lib.win-amd64-3.6\hdbscan
    copying hdbscan\plots.py -&gt; build\lib.win-amd64-3.6\hdbscan
    copying hdbscan\prediction.py -&gt; build\lib.win-amd64-3.6\hdbscan
    copying hdbscan\robust_single_linkage_.py -&gt; build\lib.win-amd64-3.6\hdbscan
    copying hdbscan\validity.py -&gt; build\lib.win-amd64-3.6\hdbscan
    copying hdbscan\__init__.py -&gt; build\lib.win-amd64-3.6\hdbscan
    creating build\lib.win-amd64-3.6\hdbscan\tests
    copying hdbscan\tests\test_hdbscan.py -&gt; build\lib.win-amd64-3.6\hdbscan\tests
    copying hdbscan\tests\test_rsl.py -&gt; build\lib.win-amd64-3.6\hdbscan\tests
    copying hdbscan\tests\__init__.py -&gt; build\lib.win-amd64-3.6\hdbscan\tests
    running build_ext
    Traceback (most recent call last):
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages\pip\_vendor\pep517\_in_process.py", line 207, in &lt;module&gt;
        main()
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages\pip\_vendor\pep517\_in_process.py", line 197, in main
        json_out['return_val'] = hook(**hook_input['kwargs'])
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\site-packages\pip\_vendor\pep517\_in_process.py", line 141, in build_wheel
        metadata_directory)
      File "C:\Users\Alienware\AppData\Local\Temp\pip-build-env-n2heecpm\overlay\Lib\site-packages\setuptools\build_meta.py", line 209, in build_wheel
        wheel_directory, config_settings)
      File "C:\Users\Alienware\AppData\Local\Temp\pip-build-env-n2heecpm\overlay\Lib\site-packages\setuptools\build_meta.py", line 194, in _build_with_temp_dir
        self.run_setup()
      File "C:\Users\Alienware\AppData\Local\Temp\pip-build-env-n2heecpm\overlay\Lib\site-packages\setuptools\build_meta.py", line 237, in run_setup
        self).run_setup(setup_script=setup_script)
      File "C:\Users\Alienware\AppData\Local\Temp\pip-build-env-n2heecpm\overlay\Lib\site-packages\setuptools\build_meta.py", line 142, in run_setup
        exec(compile(code, __file__, 'exec'), locals())
      File "setup.py", line 96, in &lt;module&gt;
        setup(**configuration)
      File "C:\Users\Alienware\AppData\Local\Temp\pip-build-env-n2heecpm\overlay\Lib\site-packages\setuptools\__init__.py", line 145, in setup
        return distutils.core.setup(**attrs)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\core.py", line 148, in setup
        dist.run_commands()
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\dist.py", line 955, in run_commands
        self.run_command(cmd)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\dist.py", line 974, in run_command
        cmd_obj.run()
      File "C:\Users\Alienware\AppData\Local\Temp\pip-build-env-n2heecpm\overlay\Lib\site-packages\wheel\bdist_wheel.py", line 192, in run
        self.run_command('build')
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\cmd.py", line 313, in run_command
        self.distribution.run_command(command)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\dist.py", line 974, in run_command
        cmd_obj.run()
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\command\build.py", line 135, in run
        self.run_command(cmd_name)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\cmd.py", line 313, in run_command
        self.distribution.run_command(command)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\dist.py", line 974, in run_command
        cmd_obj.run()
      File "setup.py", line 26, in run
        build_ext.run(self)
      File "C:\Users\Alienware\AppData\Local\Temp\pip-build-env-n2heecpm\overlay\Lib\site-packages\Cython\Distutils\old_build_ext.py", line 186, in run
        _build_ext.build_ext.run(self)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\command\build_ext.py", line 308, in run
        force=self.force)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\ccompiler.py", line 1031, in new_compiler
        return klass(None, dry_run, force)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\cygwinccompiler.py", line 285, in __init__
        CygwinCCompiler.__init__ (self, verbose, dry_run, force)
      File "c:\program files (x86)\microsoft visual studio\shared\anaconda3_64\lib\distutils\cygwinccompiler.py", line 129, in __init__
        if self.ld_version &gt;= "2.10.90":
    TypeError: '&gt;=' not supported between instances of 'NoneType' and 'str'
    ----------------------------------------
    ERROR: Failed building wheel for hdbscan
    Running setup.py clean for hdbscan
  Failed to build hdbscan
  ERROR: Could not build wheels for hdbscan which use PEP 517 and cannot be installed directly
  </code></pre>
  
  <p>Do you understand why the system could not build the wheels for hdbscan?</p>
  
  <p>Is there something I can do about it? What are the alternatives at this point?</p>
  
  <p>I tried to install the hdbscan without the binaries but again failed:</p>
  
  <pre><code>(base) C:\WINDOWS\system32&gt;pip install --upgrade --no-binary hdbscan
  ERROR: You must give at least one requirement to install (see "pip help install")
  </code></pre>
  
  <hr>
  
  <pre><code>(base) C:\WINDOWS\system32&gt;pip list outdated
  Package                            Version
  ---------------------------------- ---------------------
  matplotlib                         2.2.2
  scipy                              1.1.0
  numpy                              1.14.3
  absl-py                            0.7.1
  alabaster                          0.7.10
  anaconda-client                    1.6.14
  anaconda-navigator                 1.8.7
  anaconda-project                   0.8.2
  arviz                              0.4.1
  asn1crypto                         0.24.0
  aspy.yaml                          1.2.0
  astor                              0.7.1
  astroid                            1.6.3
  astropy                            3.0.2
  astunparse                         1.6.2
  attrs                              18.1.0
  autograd                           1.2
  Babel                              2.5.3
  backcall                           0.1.0
  backports.shutil-get-terminal-size 1.0.0
  beautifulsoup4                     4.6.0
  bitarray                           0.8.1
  bkcharts                           0.2
  blaze                              0.11.3
  bleach                             1.5.0
  blis                               0.2.4
  bokeh                              0.12.16
  boto                               2.48.0
  boto3                              1.9.130
  botocore                           1.12.130
  Bottleneck                         1.2.1
  brewer2mpl                         1.4.1
  bs4                                0.0.1
  bz2file                            0.98
  certifi                            2018.4.16
  cffi                               1.11.5
  cfgv                               1.6.0
  cftime                             1.0.3.4
  chardet                            3.0.4
  click                              6.7
  cloudpickle                        1.2.1
  clyent                             1.2.2
  colorama                           0.3.9
  colour                             0.1.5
  comtypes                           1.1.4
  conda                              4.6.8
  conda-build                        3.10.5
  conda-verify                       2.0.0
  contextlib2                        0.5.5
  convertdate                        2.1.3
  cryptography                       2.2.2
  cycler                             0.10.0
  cymem                              2.0.2
  Cython                             0.29.10
  cytoolz                            0.9.0.1
  d2l                                0.9.2
  dask                               0.17.5
  datashape                          0.5.4
  decorator                          4.3.0
  dill                               0.3.0
  distributed                        1.21.8
  Django                             2.2.2
  dltk                               0.2.1
  docutils                           0.14
  el-core-news-md                    2.1.0
  el-core-news-sm                    2.1.0
  embedder                           0.1
  en-core-web-md                     2.1.0
  entrypoints                        0.2.3
  ephem                              3.7.6.0
  et-xmlfile                         1.0.1
  fastcache                          1.0.2
  fastdtw                            0.3.2
  fasttext                           0.8.3
  fbprophet                          0.1.post1
  filelock                           3.0.4
  fix-yahoo-finance                  0.0.22
  Flask                              1.0.2
  Flask-Cors                         3.0.4
  future                             0.17.1
  gast                               0.2.2
  gensim                             3.7.1
  geojson                            2.4.1
  gevent                             1.3.0
  ggplot                             0.11.5
  glob2                              0.6
  google-pasta                       0.1.4
  googleapis-common-protos           1.6.0
  graphviz                           0.8.4
  greenlet                           0.4.13
  grpcio                             1.19.0
  gym                                0.14.0
  h5py                               2.7.1
  heapdict                           1.0.0
  hmmlearn                           0.2.2
  holidays                           0.9.10
  html5lib                           0.9999999
  hyperopt                           0.1.1
  identify                           1.4.1
  idna                               2.6
  image                              1.5.27
  imageio                            2.3.0
  imagesize                          1.0.0
  importlib-metadata                 0.9
  importlib-resources                1.0.2
  inflection                         0.3.1
  ipykernel                          4.8.2
  ipython                            6.4.0
  ipython-genutils                   0.2.0
  ipywidgets                         7.2.1
  isort                              4.3.4
  iterative-stratification           0.1.6
  itsdangerous                       0.24
  jdcal                              1.4
  jedi                               0.12.0
  Jinja2                             2.10
  jmespath                           0.9.4
  joblib                             0.13.2
  json-tricks                        3.12.2
  jsonschema                         2.6.0
  jupyter                            1.0.0
  jupyter-client                     5.2.3
  jupyter-console                    5.2.0
  jupyter-contrib-core               0.3.3
  jupyter-contrib-nbextensions       0.5.1
  jupyter-core                       4.4.0
  jupyter-highlight-selected-word    0.2.0
  jupyter-latex-envs                 1.4.6
  jupyter-nbextensions-configurator  0.4.1
  jupyterlab                         0.32.1
  jupyterlab-launcher                0.10.5
  Keras                              2.2.5
  Keras-Applications                 1.0.8
  Keras-Preprocessing                1.1.0
  keras-rl                           0.4.2
  kiwisolver                         1.0.1
  lazy-object-proxy                  1.3.1
  llvmlite                           0.23.1
  locket                             0.2.0
  lunardate                          0.2.0
  lxml                               4.4.1
  Markdown                           3.1
  MarkupSafe                         1.0
  matplotlib                         3.1.1
  mccabe                             0.6.1
  menuinst                           1.4.14
  mistune                            0.8.3
  mkl-fft                            1.0.0
  mkl-random                         1.0.1
  mock                               2.0.0
  more-itertools                     4.1.0
  mpld3                              0.3
  mpmath                             1.0.0
  msgpack                            0.6.1
  msgpack-python                     0.5.6
  multipledispatch                   0.5.0
  multitasking                       0.0.7
  murmurhash                         1.0.2
  mxnet-cu101                        1.5.0
  navigator-updater                  0.2.1
  nbconvert                          5.3.1
  nbformat                           4.4.0
  netCDF4                            1.5.1.2
  networkx                           2.1
  neuralcoref                        4.0
  nltk                               3.3
  NNI                                0.1.0
  nodeenv                            1.3.3
  nose                               1.3.7
  notebook                           5.5.0
  numba                              0.38.0
  numexpr                            2.6.5
  numpy                              1.17.2
  numpydoc                           0.8.0
  odo                                0.5.1
  olefile                            0.45.1
  opencv-python                      4.1.1.26
  openpyxl                           2.5.3
  packaging                          17.1
  pandas                             0.24.2
  pandas-datareader                  0.7.0
  pandocfilters                      1.4.2
  parso                              0.2.0
  partd                              0.3.8
  path.py                            11.0.1
  pathlib2                           2.3.2
  patsy                              0.5.0
  pbr                                5.1.3
  pep8                               1.7.1
  pickleshare                        0.7.4
  Pillow                             5.1.0
  pip                                19.2.3
  pixiedust                          1.1.13
  pkginfo                            1.4.2
  plac                               0.9.6
  plotly                             4.0.0
  pluggy                             0.6.0
  ply                                3.11
  pmdarima                           1.2.1
  pre-commit                         1.15.1
  preshed                            2.0.1
  promise                            2.2.1
  prompt-toolkit                     1.0.15
  protobuf                           3.7.1
  psutil                             5.4.5
  py                                 1.5.3
  py-translate                       1.0.3
  pybind11                           2.2.4
  pycodestyle                        2.4.0
  pycosat                            0.6.3
  pycparser                          2.18
  pycrypto                           2.6.1
  pycurl                             7.43.0.1
  pydot                              1.4.1
  pydotplus                          2.0.2
  pyflakes                           1.6.0
  pyglet                             1.3.2
  Pygments                           2.2.0
  pylint                             1.8.4
  pymongo                            3.7.1
  pyodbc                             4.0.23
  pyOpenSSL                          18.0.0
  pyparsing                          2.2.0
  PyProcessMacro                     1.0.0
  pyreadstat                         0.2.1
  PySocks                            1.6.8
  pystan                             2.19.0.0
  pytest                             3.5.1
  pytest-arraydiff                   0.2
  pytest-astropy                     0.3.0
  pytest-doctestplus                 0.1.3
  pytest-openfiles                   0.3.0
  pytest-remotedata                  0.2.1
  python-dateutil                    2.7.3
  pytz                               2018.4
  PyWavelets                         0.5.2
  pywin32                            223
  pywinpty                           0.5.1
  PyYAML                             3.12
  pyzmq                              17.0.0
  QtAwesome                          0.4.4
  qtconsole                          4.3.1
  QtPy                               1.4.1
  Quandl                             3.4.6
  regex                              2019.8.19
  requests                           2.22.0
  retrying                           1.3.3
  rope                               0.10.7
  ruamel-yaml                        0.15.35
  s3transfer                         0.2.0
  sacremoses                         0.0.34
  scikit-image                       0.15.0
  scikit-learn                       0.19.1
  scipy                              1.2.2
  seaborn                            0.9.0
  sec-edgar-downloader               2.2.1
  Send2Trash                         1.5.0
  sentencepiece                      0.1.83
  setuptools                         41.2.0
  setuptools-git                     1.2
  shap                               0.30.1
  simplegeneric                      0.8.1
  SimpleITK                          1.2.2
  simplejson                         3.16.0
  singledispatch                     3.4.0.3
  six                                1.11.0
  smart-open                         1.8.0
  snowballstemmer                    1.2.1
  sortedcollections                  0.6.1
  sortedcontainers                   1.5.10
  spacy                              2.1.3
  Sphinx                             1.7.4
  sphinxcontrib-websupport           1.0.1
  spyder                             3.2.8
  SQLAlchemy                         1.2.7
  sqlparse                           0.3.0
  srsly                              0.0.5
  statsmodels                        0.9.0
  sympy                              1.1.1
  tables                             3.4.3
  tb-nightly                         1.14.0a20190301
  tblib                              1.3.2
  tensorboard                        2.0.0
  tensorflow                         2.0.0a0
  tensorflow-datasets                1.2.0
  tensorflow-estimator               1.13.0
  tensorflow-gpu                     1.13.1
  tensorflow-metadata                0.14.0
  tensorflow-probability             0.6.0
  termcolor                          1.1.0
  terminado                          0.8.1
  testpath                           0.3.1
  tf-estimator-nightly               1.14.0.dev2019030115
  tfds-nightly                       1.2.0.dev201909050105
  Theano                             1.0.4
  thinc                              7.0.4
  toml                               0.10.0
  toolz                              0.9.0
  torch                              1.0.1
  tornado                            5.0.2
  tox                                3.8.6
  tqdm                               4.31.1
  tradingeconomics                   0.2.953
  traitlets                          4.3.2
  transformers                       2.0.0
  translate                          3.5.0
  tsfresh                            0.11.2
  tushare                            1.2.39
  typing                             3.6.4
  unicodecsv                         0.14.1
  urllib3                            1.22
  virtualenv                         16.4.3
  wasabi                             0.2.1
  wcwidth                            0.1.7
  webencodings                       0.5.1
  websocket-client                   0.56.0
  Werkzeug                           0.14.1
  wheel                              0.31.1
  widgetsnbextension                 3.2.1
  win-inet-pton                      1.0.1
  win-unicode-console                0.5
  wincertstore                       0.2
  wrapt                              1.10.11
  xarray                             0.12.3
  xgboost                            0.82
  xlrd                               1.1.0
  XlsxWriter                         1.0.4
  xlwings                            0.11.8
  xlwt                               1.3.0
  yahoo-finance                      1.4.0
  yahoofinancials                    1.5
  yfinance                           0.1.45
  zict                               0.1.3
  zipp                               0.3.3
  </code></pre>