Expert Advisor Programming by Andrew R. Young

Advanced Order Placement
Verifying Pending Order Prices
Here's how we verify the pending order price for a buy stop or sell limit order. The PendingPrice
variable stores our pending order price:
if(PendingPrice < UpperStopLevel) PendingPrice = UpperStopLevel + MinStop;
Notice that the logic here is identical to the code above that checks our buy take profit and sell stop
loss prices. And here's the code to check the pending order price for a sell stop or buy limit order:
if(PendingPrice > UpperStopLevel) PendingPrice = UpperStopLevel – MinStop;
Calculating Lot Size
Aside from choosing suitable stop loss and take profit levels, using an appropriate lot size is one of
the best risk management tools you have. Specifying a lot size can be as simple as declaring an
external variable and using a fixed lot size for every order. In this section, we'll explore a more
sophisticated method that calculates the lot size based on the maximum amount you're willing to lose
per trade.
Over-leveraging is one of the big killers of forex traders. Using lot sizes that are too large in relation
to your equity can wipe out your account just as easily as it can produce big gains. It is
recommended that you use no more than 2-3% of your equity per trade. By this, we mean that the
maximum amount you can lose per trade will be no more that 2-3% of your account.
Money Management
To calculate the lot size using this method, we need to specify a percentage of equity to use and the
stop loss in pips. We'll use the external variable EquityPercent to set the percentage of equity to
use. We'll assume a stop loss of 50 pips is used.
extern double EquityPercent = 2;
extern double StopLoss = 50;
First, we need to calculate the amount of equity specified by EquityPercent. If we have a balance
of $10,000, and we are using 2% of our equity, then the calculation is as follows:
double RiskAmount = AccountEquity() * (EquityPercent / 100);
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