text: import numpy as np
  import numpy.testing as npt
  import pytest
  import matplotlib.pyplot as plt
  
  
  import lenstronomy.Plots.plot_util as plot_util
  
  
  class TestPlotUtil(object):
  
      def setup(self):
          pass
  
      def test_sqrt(self):
          image = np.random.randn(10, 10)
          image_rescaled = plot_util.sqrt(image)
          npt.assert_almost_equal(np.min(image_rescaled), 0)
  
      def test_scale_bar(self):
          f, ax = plt.subplots(1, 1, figsize=(4, 4))
          plot_util.scale_bar(ax, 3, dist=1, text='1"', flipped=True)
          plt.close()
          f, ax = plt.subplots(1, 1, figsize=(4, 4))
          plot_util.text_description(ax, d=3, text='test', color='w', backgroundcolor='k', flipped=True)
          plt.close()
  
      def test_source_position_plot(self):
          from lenstronomy.PointSource.point_source import PointSource
          from lenstronomy.LensModel.lens_model import LensModel
          lensModel = LensModel(lens_model_list=['SIS'])
          ps = PointSource(point_source_type_list=['UNLENSED', 'LENSED_POSITION', 'SOURCE_POSITION'], lensModel=lensModel)
          kwargs_lens = [{'theta_E': 1., 'center_x': 0, 'center_y': 0}]
          kwargs_ps = [{'ra_image': [1., 1.], 'dec_image': [0, 1], 'point_amp': [1, 1]},
                            {'ra_image': [1.], 'dec_image': [1.], 'point_amp': [10]},
                            {'ra_source': 0.1, 'dec_source': 0, 'point_amp': 1.}]
          ra_source, dec_source = ps.source_position(kwargs_ps, kwargs_lens)
          from lenstronomy.Data.coord_transforms import Coordinates
          coords_source = Coordinates(transform_pix2angle=np.array([[1, 0], [0, 1]])* 0.1,
                                      ra_at_xy_0=-2,
                                      dec_at_xy_0=-2)
  
          f, ax = plt.subplots(1, 1, figsize=(4, 4))
          plot_util.source_position_plot(ax, coords_source, ra_source, dec_source)
          plt.close()
  
      def test_result_string(self):
          x = np.random.normal(loc=1, scale=0.1, size=10000)
          string =plot_util.result_string(x, weights=None, title_fmt=".2f", label='test')
          print(string)
          assert string == str('test = ${1.00}_{-0.10}^{+0.10}$')
  
      def test_cmap_conf(self):
          cmap = plot_util.cmap_conf(cmap_string='gist_heat')
          cmap_update = plot_util.cmap_conf(cmap_string=cmap)
          assert cmap is cmap_update
  
  
  
  if __name__ == '__main__':
      pytest.main()
  