class_docstr: Test VISSR file handler.
class_docstr_tok: ["Test","VISSR","file","handler","."]
docstr: Get parameters for coordinate conversions.
  
  Adjust pixel offset so that the first column is at the image center.
  This has the advantage that we can test with very small 2x2 images.
  Otherwise, all pixels would be in space.
docstr_tok: ["Get","parameters","for","coordinate","conversions",".","Adjust","pixel","offset","so","that","the","first","column","is","at","the","image","center",".","This","has","the","advantage","that","we","can","test","with","very","small","2x2","images",".","Otherwise",",","all","pixels","would","be","in","space","."]
code: def coord_conv(self):
      """Get parameters for coordinate conversions.
  
      Adjust pixel offset so that the first column is at the image center.
      This has the advantage that we can test with very small 2x2 images.
      Otherwise, all pixels would be in space.
      """
      conv = np.zeros(1, dtype=fmt.COORDINATE_CONVERSION_PARAMETERS)
  
      cline = conv["central_line_number_of_vissr_frame"]
      cline["IR1"] = 1378.5
      cline["VIS"] = 5513.0
  
      cpix = conv["central_pixel_number_of_vissr_frame"]
      cpix["IR1"] = 0.5  # instead of 1672.5
      cpix["VIS"] = 0.5  # instead of 6688.5
  
      conv["scheduled_observation_time"] = 50130.979089568464
  
      nsensors = conv["number_of_sensor_elements"]
      nsensors["IR1"] = 1
      nsensors["VIS"] = 4
  
      sampling_angle = conv["sampling_angle_along_pixel"]
      sampling_angle["IR1"] = 9.5719995e-05
      sampling_angle["VIS"] = 2.3929999e-05
  
      stepping_angle = conv["stepping_angle_along_line"]
      stepping_angle["IR1"] = 0.00014000005
      stepping_angle["VIS"] = 3.5000005e-05
  
      conv["matrix_of_misalignment"] = np.array(
          [
              [9.9999917e-01, -5.1195198e-04, -1.2135329e-03],
              [5.1036407e-04, 9.9999905e-01, -1.3083406e-03],
              [1.2142011e-03, 1.3077201e-03, 9.9999845e-01],
          ],
          dtype=np.float32,
      )
  
      conv["parameters"]["equatorial_radius"] = 6377397.0
      conv["parameters"]["oblateness_of_earth"] = 0.003342773
  
      conv["orbital_parameters"]["longitude_of_ssp"] = 141.0
      conv["orbital_parameters"]["latitude_of_ssp"] = 1.0
      return conv
  
imports: import datetime
  import gzip
  import fsspec
  import numpy
  import pytest
  import xarray
  from pyresample.geometry import AreaDefinition
  import satpy.tests.reader_tests.gms.test_gms5_vissr_data
  from satpy.readers import FSFile
  from satpy.tests.reader_tests.utils import get_jit_methods, skip_numba_unstable_if_missing
  from satpy.tests.utils import make_dataid
label_desc: Use image node_id 14 for calling the TestFileHandler obj's underlying member method code with example usage: obj.coord_conv() and returns: conv