They are available in the strategy settings, in the Properties tab:
Each of the parameters specified in the properties of the strategy can be changed by editing the arguments of the strategy() function call in the corresponding Pine script:
strategy(title, initial_capital, currency, default_qty_value, default_qty_type, pyramiding, commission_type, commission_value, backtest_fill_limits_assumption, slippage, process_orders_on_close, margin_long, margin_short, calc_on_order_fills, calc_on_every_tick)
Let's take a look at each input parameter in the Properties menu and its corresponding parameter in the Pine language:
1 - Initial Capital (parameter: initial_capital) represents the amount of funds initially available for the strategy to trade, in the currency defined in Base Currency. By default, this value is equal to 100,000. You may need to increase this value for trades to occur on certain symbols.
2 - Base Currency (parameter: currency) specifies the currency used for calculations. Results appearing in the Strategy Tester tab (profit, loss, drawdown, etc) are expressed in this currency. Available choices are:
Default, USD, EUR, AUD, GBP, NZD, CAD, CHF, HKD, JPY, NOK, SEK, SGD, TRY, ZAR. If the Default choice is selected, the strategy will use the default currency for this symbol and there is no currency conversion.
3 - Order Size (parameters: default_qty_value, default_qty_type). This requires a value and a calculation mode. Note that the calculated values can be subject to constraints due to the minimum tradable quantities for the symbol:
4 - Pyramiding (parameter: pyramiding) specifies the maximum number of successive entries allowed in the same direction. When pyramiding is disabled, the strategy can only open one long or short position, even if entry conditions are met. Pyramiding only affects entries made using the strategy.entry() function. It has no effect on orders created using strategy.order().
5 - Commission (parameters: commission_type, commission_value). It is the amount paid in trading fees for each trade. A value and calculation mode must be supplied. Note that commission is applied on both entries and exits, and that when a percentage is used, the calculated commission will vary with the value of the transaction:
6 - Verify Price For Limit Orders (parameter: backtest_fill_limits_assumption) makes the conditions for entering a position using limit orders more strict. By default, this value is 0, i.e. limit orders are filled on historical data as soon as the price indicated in the order is reached. If the parameter is not zero, then limit orders can enter a position within the bar only if the market price has exceeded the level of the limit order by the specified number of ticks.
7 - Slippage (parameter: slippage) specifies the value in ticks to be added to the fill price of market or stop orders. It can be used to account for the spread.
8 - Margin For Long and Short Positions (parameters: margin_long, margin_short) the margin required to maintain the position. If there are not enough funds, then a margin call occurs, which forcibly closes part or all of the positions with a market order until there are enough funds to maintain the existing positions.
9 - Recalculate options specify how often the strategy should be recalculated. By default, the strategy is recalculated at the close of each bar, but using the options below, it can also be recalculated: