The Reader Class

Understanding the Reader keyword arguments

• JSONdir=None - This should be the name of the sub-directory that will contain your JSON files, if you are not running python from /path/to/Firefly/data it should be the absolute path.

• options=None - An Options instance, if you have created one you can pass it here. None will generate default options. reader.options.listKeys() will give you a list of the different available options you can set using reader.options["option_name"] = option_value.

• write_startup='append' - This is a flag for whether startup.json file should be written. It has 3 values: True -> writes a new startup.json that will contain only this visualization, 'append' -> which will add this visualization to an existing startup.json (or create a new one), this is the default option, or False -> which will not add an entry to startup.json.

• max_npart_per_file=10000 - The maximum number of particles saved per file, don't use too large a number or you will have trouble loading the individual files in.

• prefix='Data' - What you would like your .json files to be called when you run reader.dumpToJSON. The format is (prefix)(particleGroupName)(fileNumber).json.

• clean_JSONdir=0 - Whether you would like to delete all .json files in the JSONdir. Usually not necessary (since filenames.json will be updated) but good to clean up after yourself.