code: def test_same_basis(data):
      arr4d = data["fmridata"]
      shp = arr4d.shape
      arr2d = arr4d.reshape((np.prod(shp[:3]), shp[3]))
      res = pos1pca(arr2d, axis=-1)
      p1b_0 = res["basis_vectors"]
      for i in range(3):
          res_again = pos1pca(arr2d, axis=-1)
          assert_almost_equal(res_again["basis_vectors"], p1b_0)
  
imports: import numpy
  import pytest
  from nipy.io.api import load_image
  from nipy.testing import assert_almost_equal, assert_array_almost_equal, funcfile
  from ..pca import pca
label_desc: Use image node_id 6 for calling a global function with example usage: test_same_basis(data) without return types