Better formula

Using the scout margin,
- the bot performs more consistently when trade fees vary.
- Easy to understand.
- Fixes instant/unnecessary trade bug.
- ratio_dict will also represent which coins are closest to trading.

.user.cfg.example

@@ -5,7 +5,9 @@ current_coin=
 bridge=USDT
 tld=com
 hourToKeepScoutHistory=1
+use_margin=no
 scout_multiplier=5
+scout_margin=0.8
 scout_sleep_time=1
 strategy=default
 buy_timeout=0

README.md

@@ -57,7 +57,9 @@ Create a .cfg file named `user.cfg` based off `.user.cfg.example`, then add your
 -   **tld** - 'com' or 'us', depending on your region. Default is 'com'.
 -   **hourToKeepScoutHistory** - Controls how many hours of scouting values are kept in the database. After the amount of time specified has passed, the information will be deleted.
 -   **scout_sleep_time** - Controls how many seconds are waited between each scout.
+-   **use_margin** - 'yes' to use scout_margin. 'no' to use scout_multiplier.
 -   **scout_multiplier** - Controls the value by which the difference between the current state of coin ratios and previous state of ratios is multiplied. For bigger values, the bot will wait for bigger margins to arrive before making a trade.
+-   **scout_margin** - Minimum percentage coin gain per trade. 0.8 translates to a scout multiplier of 5 at 0.1% fee.
 -   **strategy** - The trading strategy to use. See [`binance_trade_bot/strategies`](binance_trade_bot/strategies/README.md) for more information
 -   **buy_timeout/sell_timeout** - Controls how many minutes to wait before cancelling a limit order (buy/sell) and returning to "scout" mode. 0 means that the order will never be cancelled prematurely.
 -   **scout_sleep_time** - Controls how many seconds bot should wait between analysis of current prices. Since the bot now operates on websockets this value should be set to something low (like 1), the reasons to set it above 1 are when you observe high CPU usage by bot or you got api errors about requests weight limit.

binance_trade_bot/auto_trader.py

@@ -123,13 +123,19 @@ def _get_ratios(self, coin: Coin, coin_price):
             # Obtain (current coin)/(optional coin)
             coin_opt_coin_ratio = coin_price / optional_coin_price
 
-            transaction_fee = self.manager.get_fee(pair.from_coin, self.config.BRIDGE, True) + self.manager.get_fee(
-                pair.to_coin, self.config.BRIDGE, False
-            )
-
-            ratio_dict[pair] = (
-                coin_opt_coin_ratio - transaction_fee * self.config.SCOUT_MULTIPLIER * coin_opt_coin_ratio
-            ) - pair.ratio
+            # Fees
+            from_fee = self.manager.get_fee(pair.from_coin, self.config.BRIDGE, True)
+            to_fee = self.manager.get_fee(pair.to_coin, self.config.BRIDGE, False)
+            transaction_fee = from_fee + to_fee - from_fee * to_fee
+
+            if self.config.USE_MARGIN == "yes":
+                ratio_dict[pair] = (
+                    (1- transaction_fee) * coin_opt_coin_ratio / pair.ratio - 1 - self.CONFIG.SCOUT_MARGIN
+                    )
+            else:
+                ratio_dict[pair] = (
+                    coin_opt_coin_ratio - transaction_fee * self.config.SCOUT_MULTIPLIER * coin_opt_coin_ratio
+                ) - pair.ratio
         return ratio_dict
 
     def _jump_to_best_coin(self, coin: Coin, coin_price: float):

binance_trade_bot/config.py

@@ -14,7 +14,9 @@ def __init__(self):
         config = configparser.ConfigParser()
         config["DEFAULT"] = {
             "bridge": "USDT",
+            "use_margin": "no",
             "scout_multiplier": "5",
+            "scout_margin": "0.8",
             "scout_sleep_time": "5",
             "hourToKeepScoutHistory": "1",
             "tld": "com",
@@ -70,3 +72,6 @@ def __init__(self):
 
         self.SELL_TIMEOUT = os.environ.get("SELL_TIMEOUT") or config.get(USER_CFG_SECTION, "sell_timeout")
         self.BUY_TIMEOUT = os.environ.get("BUY_TIMEOUT") or config.get(USER_CFG_SECTION, "buy_timeout")
+
+        self.USE_MARGIN = os.environ.get("USE_MARGIN") or config.get(USER_CFG_SECTION, "use_margin")
+        self.SCOUT_MARGIN = os.environ.get("SCOUT_MARGIN") or config.get(USER_CFG_SECTION, "scout_margin")