class_docstr: VIRR Level 1b reader.
class_docstr_tok: ["VIRR","Level","1b","reader","."]
code: def _calibrate_reflective(self, data, band_index):
      if self.platform_id == "FY3B":
          coeffs = da.from_array(FY3B_REF_COEFFS, chunks=-1)
      else:
          coeffs = self["/attr/RefSB_Cal_Coefficients"]
      slope = self._correct_slope(coeffs[0::2])
      intercept = coeffs[1::2]
      data = data * slope[band_index] + intercept[band_index]
      return data
  
file_path: satpy/satpy/readers/virr_l1b.py
imports: import logging
  from datetime import datetime
  import dask.array
  import numpy
  from pyspectral.blackbody import blackbody_wn_rad2temp
  from satpy.readers.hdf5_utils import HDF5FileHandler
label_desc: Use image node_id 3 for calling the VIRR_L1B obj's underlying member method code with example usage: obj._calibrate_reflective(data, band_index) and returns: data