code: def test_empty(self, xp, scp):
      # When there are no relative extrema, make sure that
      # the number of empty arrays returned matches the
      # dimension of the input.
      z1 = xp.zeros(5)
      i = scp.signal.argrelmin(z1)
  
      z2 = xp.zeros((3, 5))
      row1, col1 = scp.signal.argrelmin(z2, axis=0)
      row2, col2 = scp.signal.argrelmin(z2, axis=1)
      return i[0], row1, col1, row2, col2
  
imports: import pytest
  import cupy
  from cupy.cuda import driver
  from cupy.cuda import runtime
  from cupy import testing
  import cupyx.scipy.signal
  import numpy
label_desc: Use image node_id 1 for calling the TestArgrel obj's underlying member method code with example usage: obj.test_empty(xp, scp) and returns: i,  row1,  col1,  row2,  col2