docstr: Variations on the constructors in the Elements notebook
docstr_tok: ["Variations","on","the","constructors","in","the","Elements","notebook"]
code: def setUp(self):
      "Variations on the constructors in the Elements notebook"
  
      key_dims1 = [Dimension("Car occupants")]
      key_dims2 = [Dimension("Cyclists")]
      value_dims1 = ["Count"]
      self.bars1 = Bars(
          [("one", 8), ("two", 10), ("three", 16)],
          kdims=key_dims1,
          vdims=value_dims1,
      )
      self.bars2 = Bars(
          [("one", 8), ("two", 10), ("three", 17)],
          kdims=key_dims1,
          vdims=value_dims1,
      )
      self.bars3 = Bars(
          [("one", 8), ("two", 10), ("three", 16)],
          kdims=key_dims2,
          vdims=value_dims1,
      )
  
imports: import numpy
  from holoviews import Bars, Curve, Dimension, Histogram, Points, Scatter, VectorField
  from holoviews.element.comparison import ComparisonTestCase
label_desc: Use image node_id 1 for calling the BarsComparisonTest obj's underlying member method code with example usage: obj.setUp() without return types