code: def test_fractional_n_components():
      X = da.random.uniform(size=(10, 5), chunks=(5, 5))
      pca = dd.PCA(n_components=0.5)
      with pytest.raises(NotImplementedError) as w:
          pca.fit(X)
  
      assert w.match("Fractional 'n_components'")
  
imports: from itertools import product
  import dask.array
  import dask.dataframe
  import numpy
  import pandas
  import pytest
  import scipy
  import sklearn.decomposition
  from dask.array.utils import assert_eq
  from numpy.testing import assert_almost_equal, assert_array_almost_equal, assert_raises
  from sklearn import datasets
  from sklearn.utils import check_random_state
  import dask_ml.decomposition
  from dask_ml._compat import DASK_2_26_0
  from dask_ml.utils import assert_estimator_equal, flip_vector_signs, svd_flip
label_desc: Use image node_id 29 for calling a global function with example usage: test_fractional_n_components() without return types