A helper to calculate stoploss value from absolute price.

freqtrade/strategy/__init__.py

@@ -4,4 +4,5 @@ from freqtrade.exchange import (timeframe_to_minutes, timeframe_to_msecs, timefr
 from freqtrade.strategy.hyper import (BooleanParameter, CategoricalParameter, DecimalParameter,
                                       IntParameter, RealParameter)
 from freqtrade.strategy.interface import IStrategy
-from freqtrade.strategy.strategy_helper import merge_informative_pair, stoploss_from_open
+from freqtrade.strategy.strategy_helper import (merge_informative_pair,
+                                                stoploss_from_absolute, stoploss_from_open)

freqtrade/strategy/strategy_helper.py

@@ -83,3 +83,14 @@ def stoploss_from_open(open_relative_stop: float, current_profit: float) -> floa
 
     # negative stoploss values indicate the requested stop price is higher than the current price
     return max(stoploss, 0.0)
+
+
+def stoploss_from_absolute(stop_rate: float, current_rate: float) -> float:
+    """
+    Given current price and desired stop price, return a stop loss value that is relative to current
+    price.
+    :param stop_rate: Stop loss price.
+    :param current_rate: Current asset price.
+    :return: Positive stop loss value relative to current price
+    """
+    return 1 - (stop_rate / current_rate)