In this tutorial, we’ll explore the `strategy.opentrades.commission()`

function in Pine Script, a pivotal tool in quantifying the entry and exit fees associated with open trades within a trading strategy. This function is instrumental in creating more accurate and financially realistic trading strategy simulations.

### Syntax

The function is declared as follows:

strategy.opentrades.commission(trade_num) → series float

#### Arguments

**trade_num**(`series int`

): This argument specifies the number of the open trade for which you want to calculate the commission. It’s important to note that trade numbering starts at zero.

### Example

Let’s dive into a practical example that illustrates how to use `strategy.opentrades.commission()`

in a trading strategy. This example focuses on calculating the gross profit or loss for current open positions, taking into account the commissions paid.

//@version=5 strategy("Commission Analysis Example", commission_type = strategy.commission.percent, commission_value = 0.1) // Strategy setup for entering and exiting long trades. if bar_index % 15 == 0 strategy.entry("MyLongEntry", strategy.long) if bar_index % 20 == 0 strategy.close("MyLongEntry") // Function to calculate gross profit or loss for open positions. calculateTradeOpenGrossPL() => totalOpenGrossPL = 0.0 for tradeIndex = 0 to strategy.opentrades - 1 totalOpenGrossPL += strategy.opentrades.profit(tradeIndex) - strategy.opentrades.commission(tradeIndex) totalOpenGrossPL plot(calculateTradeOpenGrossPL())

### Detailed Walkthrough

**Strategy Definition**: We start by defining a strategy called “Commission Analysis Example”. Here, we specify that commissions are calculated as a percentage of the trade value, set at 0.1%.**Entry and Exit Conditions**: The script contains logic to enter long positions (`strategy.entry`

) every 15 bars and exit (`strategy.close`

) every 20 bars.**Gross Profit or Loss Calculation**: The`calculateTradeOpenGrossPL()`

function computes the gross profit or loss for all open trades. It initializes a variable`totalOpenGrossPL`

to accumulate the sum of open trade profits minus their associated commissions.**Loop Through Open Trades**: A loop iterates through all open trades, using`strategy.opentrades.profit(tradeIndex)`

to calculate the profit for each open trade and subtracting`strategy.opentrades.commission(tradeIndex)`

to account for the commissions paid on both entry and exit.**Plotting the Result**: Finally, the calculated total open gross profit or loss is plotted on the chart for visualization.

### Key Features and Takeaways

**Function Useability**: The`strategy.opentrades.commission()`

function is essential for calculating the total commissions paid for an open trade, offering a more nuanced view of trading strategy profitability.**Syntax and Application**: Its straightforward syntax and integration within loop constructs make it highly effective for dynamic trade analysis over time.**Enhanced Strategy Simulation**: By including entry and exit fees in profitability calculations, traders can simulate strategies more accurately, leading to better-informed trading decisions.

In summary, understanding and effectively utilizing the `strategy.opentrades.commission()`

function is crucial for anyone looking to develop sophisticated and realistic trading strategies in Pine Script.