def modis_diff(domain, b, threshold=None):
    if threshold == None: # If no threshold value passed in, load it based on the data set.
        threshold = float(domain.algorithm_params['modis_diff_threshold'])
    return get_diff(b).lte(threshold)

#==============================================================
Returns the dynamic data document as dictionary -- see top of file for reference
dataset/ETHPy150Open nasa/CrisisMappingToolkit/cmt/modis/simple_modis_algorithms.py/modis_diff--crossover with--dataset/ETHPy150Open wcannon/saltconf2015/phoenix/infrastructure/s3/minion/scripts/helper.py/Helper.get_dynamic_metadata