code: def test_raster_subpixel_quads_represented(array_module):
      c = ds.Canvas(
          plot_width=8,
          plot_height=4,
          x_range=[0.5, 16.5],
          y_range=[0.5, 8.5],
      )
  
      da = xr.DataArray(
          array_module.array([[1, 2, 3, 4], [5, 6, 7, 8]]),
          coords=[("b", [1, 2]), ("a", [1, 2, 3, 4])],
          name="Z",
      )
  
      y_coords = np.linspace(1.5, 7.5, 4)
      x_coords = np.linspace(1.5, 15.5, 8)
      out = xr.DataArray(
          array_module.array(
              [
                  [14.0, 22.0, nan, nan, nan, nan, nan, nan],
                  [nan, nan, nan, nan, nan, nan, nan, nan],
                  [nan, nan, nan, nan, nan, nan, nan, nan],
                  [nan, nan, nan, nan, nan, nan, nan, nan],
              ],
              dtype="f4",
          ),
          coords=[("b", y_coords), ("a", x_coords)],
      )
  
      res = c.quadmesh(da, x="a", y="b", agg=ds.sum("Z"))
      assert_eq_xr(res, out)
  
      # Check transpose gives same answer
      res = c.quadmesh(
          da.transpose("a", "b"), x="a", y="b", agg=ds.sum("Z")
      )
      assert_eq_xr(res, out)
  
imports: from __future__ import annotations
  import numpy
  from numpy import nan
  import xarray
  import datashader
  import pytest
  import dask.array
  from datashader.tests.test_pandas import assert_eq_ndarray, assert_eq_xr
label_desc: Use image node_id 8 for calling a global function with example usage: test_raster_subpixel_quads_represented(array_module) without return types