code: def values(
      cls,
      dataset,
      dimension,
      expanded=True,
      flat=True,
      compute=True,
      keep_index=False,
  ):
      dimension = dataset.get_dimension(dimension)
      geom_dims = dataset.interface.geom_dims(dataset)
      data = dataset.data
      isgeom = dimension in geom_dims
      geom_col = cls.geo_column(dataset.data)
      is_points = cls.geom_type(dataset) == "Point"
      if not len(data):
          dtype = (
              float if isgeom else dataset.data[dimension.name].dtype
          )
          return np.array([], dtype=dtype)
  
      col = cls.geo_column(dataset.data)
      if isgeom and keep_index:
          return data[col]
      elif not isgeom:
          return get_value_array(
              data,
              dimension,
              expanded,
              keep_index,
              geom_col,
              is_points,
              geom_length,
          )
          column = data[dimension.name]
          if not expanded or keep_index or not len(data):
              return column if keep_index else column.values
          else:
              arrays = []
              for i, geom in enumerate(data[col]):
                  length = geom_length(geom)
                  arrays.append(np.full(length, column.iloc[i]))
              return (
                  np.concatenate(arrays)
                  if len(arrays) > 1
                  else arrays[0]
              )
  
      # There's special handling of the geometry column in the event
      # that it's not name `geometry` in the geodataframe. Since we
      # serialize each row to a geom_dictionary that requires a
      # `geometry` key.
      dict_data = data.iloc[0].to_dict()
      default_geo_name = new_geo_col_name = "geometry"
      geom_col = data.geometry.name
      if geom_col != default_geo_name:
          if default_geo_name in dict_data:
              # When there's a 'geometry' column that is not THE geometry column,
              # we create a temporary name that will be used to 1) create a new
              # dimension in the dataset and 2) add the data of this dimension
              # in the dict used to serialize each row of the geodataframe.
              while new_geo_col_name in dict_data:
                  new_geo_col_name += "_"
  
      if new_geo_col_name != default_geo_name:
          dict_data[new_geo_col_name] = dict_data.pop(default_geo_name)
          dataset = dataset.redim(
              **{default_geo_name: new_geo_col_name}
          )
  
      dict_data["geometry"] = dict_data.pop(data.geometry.name)
  
      ds = dataset.clone(dict_data, datatype=["geom_dictionary"])
      values = []
      geom_type = data.geom_type.iloc[0]
      for _i, row in data.iterrows():
          ds.data = row.to_dict()
          if new_geo_col_name != default_geo_name:
              ds.data[new_geo_col_name] = ds.data.pop(default_geo_name)
          ds.data["geometry"] = ds.data.pop(data.geometry.name)
          values.append(ds.interface.values(ds, dimension))
          if "Point" not in geom_type and expanded:
              values.append([np.nan])
      values = (
          values
          if "Point" in geom_type or not expanded
          else values[:-1]
      )
      if not values:
          return np.array([])
      elif not expanded:
          array = np.empty(len(values), dtype=object)
          array[:] = values
          return array
      elif len(values) == 1:
          return values[0]
      else:
          return np.concatenate(values)
  
imports: import sys
  import warnings
  from collections import defaultdict
  import numpy
  import pandas
  from holoviews.core.util import isscalar, unique_iterator, unique_array
  from holoviews.core.data import Dataset, Interface, MultiInterface, PandasAPI
  from holoviews.core.data.interface import DataError
  from holoviews.core.data import PandasInterface
  from holoviews.core.data.spatialpandas import get_value_array
  from holoviews.core.dimension import dimension_name
  from holoviews.element import Path
  from ..util import asarray, geom_to_array, geom_types, geom_length
  from .geom_dict import geom_from_dict
label_desc: Use image node_id 26 for calling the GeoPandasInterface obj's underlying member method code with example usage: obj.values(cls, dataset, dimension, expanded, flat, compute, keep_index) and returns: np, data, np, get_value_array, array, unknown, unknown, values, np