解决问题

TypeError: Object of type 'ndarray' is not JSON serializable

解决方法

def default(self, obj):
    if isinstance(obj, (numpy.int_, numpy.intc, numpy.intp, numpy.int8,
        numpy.int16, numpy.int32, numpy.int64, numpy.uint8,
        numpy.uint16,numpy.uint32, numpy.uint64)):
        return int(obj)
    elif isinstance(obj, (numpy.float_, numpy.float16, numpy.float32, 
        numpy.float64)):
        return float(obj)
    elif isinstance(obj, (numpy.ndarray,)): # add this line
        return obj.tolist() # add this line
    return json.JSONEncoder.default(self, obj)

成功解决！