# Buggy code
def price_to_precision(self, pair, price: float) -> float:
    """
    Returns the price rounded up to the precision the Exchange accepts.
    Partial Reimplementation of ccxt internal method decimal_to_precision(),
    which does not support rounding up
    TODO: If ccxt supports ROUND_UP for decimal_to_precision(), we could remove this and
    align with amount_to_precision().
    Rounds up
    """
    if self.markets[pair]["precision"]["price"]:
        # price = float(decimal_to_precision(price, rounding_mode=ROUND,
        #                                    precision=self.markets[pair]['precision']['price'],
        #                                    counting_mode=self.precisionMode,
        #                                    ))
        if self.precisionMode == TICK_SIZE:
            precision = self.markets[pair]["precision"]["price"]
            missing = price % precision
            if missing != 0:
                price = price - missing + precision
        else:
            symbol_prec = self.markets[pair]["precision"]["price"]
            big_price = price * pow(10, symbol_prec)
            price = ceil(big_price) / pow(10, symbol_prec)
    return price


# Traceback (Exception)
2020-02-20 22:47:28,025 - freqtrade - ERROR - Fatal exception!
Traceback (most recent call last):
File "/opt/tradebot/freqtrade/.env/lib/python3.7/site-packages/talib/__init__.py", line 20, in wrapper
for arg in chain(args, kwargs.values())
StopIteration

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/freqtrade/freqtrade/main.py", line 36, in main
return_code = args['func'](args)
File "/freqtrade/freqtrade/commands/optimize_commands.py", line 76, in start_hyperopt
hyperopt.start()
File "/freqtrade/freqtrade/optimize/hyperopt.py", line 488, in start
preprocessed = self.backtesting.strategy.tickerdata_to_dataframe(data)
File "/freqtrade/freqtrade/strategy/interface.py", line 448, in tickerdata_to_dataframe
for pair, pair_data in tickerdata.items()}
File "/freqtrade/freqtrade/strategy/interface.py", line 448, in <dictcomp>
for pair, pair_data in tickerdata.items()}
File "/freqtrade/freqtrade/strategy/interface.py", line 464, in advise_indicators
return self.populate_indicators(dataframe, metadata)
File "/freqtrade/user_data/strategies/MyDev.py", line 205, in populate_indicators
dataframe['mfi'] = ta.MFI(dataframe)
File "talib/_abstract.pxi", line 352, in talib._ta_lib.Function.__call__
File "talib/_abstract.pxi", line 383, in talib._ta_lib.Function.__call_function
File "/opt/tradebot/freqtrade/.env/lib/python3.7/site-packages/talib/__init__.py", line 24, in wrapper
return func(*args, **kwargs)
File "talib/_func.pxi", line 8454, in talib._ta_lib.MFI
Exception: volume is not double

# Fixed code
def price_to_precision(self, pair: str, price: float) -> float:
    """
    Returns the price rounded up to the precision the Exchange accepts.
    Partial Reimplementation of ccxt internal method decimal_to_precision(),
    which does not support rounding up
    TODO: If ccxt supports ROUND_UP for decimal_to_precision(), we could remove this and
    align with amount_to_precision().
    Rounds up
    """
    if self.markets[pair]["precision"]["price"]:
        # price = float(decimal_to_precision(price, rounding_mode=ROUND,
        #                                    precision=self.markets[pair]['precision']['price'],
        #                                    counting_mode=self.precisionMode,
        #                                    ))
        if self.precisionMode == TICK_SIZE:
            precision = self.markets[pair]["precision"]["price"]
            missing = price % precision
            if missing != 0:
                price = price - missing + precision
        else:
            symbol_prec = self.markets[pair]["precision"]["price"]
            big_price = price * pow(10, symbol_prec)
            price = ceil(big_price) / pow(10, symbol_prec)
    return price