NAME

       mintpy-add_attribute - Add/Update attributes to file.

DESCRIPTION

       usage: add_attribute.py file metadata_file

              add_attribute.py file key1=value1 [key2=value2 [...]]

       Add/Update attributes to file.

   Example:
       add_attribute.py timeseries.h5
              unavco_attribute.txt

       add_attribute.py timeseries.h5
              track=422   frame=650

       add_attribute.py ifgramStack.h5 ref_y=None
              ref_x=None  #Use None value to delete attribute