quandl.py 文件源码

def _format_wiki_url(self,
                         api_key,
                         symbol,
                         start_date,
                         end_date,
                         data_frequency):
        """
        Build a query URL for a quandl WIKI dataset.
        """
        query_params = [
            ('start_date', start_date.strftime('%Y-%m-%d')),
            ('end_date', end_date.strftime('%Y-%m-%d')),
            ('order', 'asc'),
        ]
        if api_key is not None:
            query_params = [('api_key', api_key)] + query_params

        return (
            "https://www.quandl.com/api/v3/datasets/WIKI/"
            "{symbol}.csv?{query}".format(
                symbol=symbol,
                query=urlencode(query_params),
            )
        )