class_docstr: File handler for MODIS HDF-EOS Level 3 CMG gridded files.
class_docstr_tok: ["File","handler","for","MODIS","HDF-EOS","Level","3","CMG","gridded","files","."]
docstr: Compute the resolution from the file metadata.
docstr_tok: ["Compute","the","resolution","from","the","file","metadata","."]
code: def _get_res(self):
      """Compute the resolution from the file metadata."""
      gridname = self.metadata["GridStructure"]["GRID_1"]["GridName"]
      if "CMG" not in gridname:
          raise ValueError("Only CMG grids are supported")
  
      # Get the grid resolution from the grid name
      pos = gridname.rfind("_") + 1
      pos2 = gridname.rfind("Deg")
  
      # Initialise number of rows and columns
      # Some products don't have resolution listed.
      if pos < 0 or pos2 < 0:
          return (
              360.0 / self.metadata["GridStructure"]["GRID_1"]["XDim"]
          )
      else:
          return float(gridname[pos:pos2])
  
file_path: satpy/satpy/readers/modis_l3.py
imports: import logging
  from typing import Iterable
  from pyresample import geometry
  from satpy.readers.hdfeos_base import HDFEOSGeoReader
label_desc: Use image node_id 3 for calling the ModisL3GriddedHDFFileHandler obj's underlying member method code with example usage: obj._get_res() and returns: unknown, float