why this expression return me 0?

[CaneRandagio]

I have this piece of code in a library and it works fine, I reported it in a script and "maxRiskInPrice" turns out to be 0.
"Account balance" is approximately € 9500.

void calculateLots(){

   int stopLossInPoints = 15;
   int riskPercentage = 5;
   double pipValue = SymbolInfoDouble(Symbol(), SYMBOL_TRADE_TICK_VALUE);
   double accountBalance = AccountInfoDouble(ACCOUNT_BALANCE);
   double maxRiskInPrice = accountBalance * (riskPercentage / 100);
   
   printf("pipValue=" + pipValue + " accountBalance=" + accountBalance + " maxRiskInPrice=" + maxRiskInPrice);
         
   lots = maxRiskInPrice  / (pipValue * stopLossInPoints) ; 
   lots = floor(lots * 100) / 100; 
   lots = NormalizeDouble(lots, 2);
   printf("lots=" + lots);

}

Where is the mistake?

thanks

[Md Atikur Rahman]

This is how I calculate lot size

// 1% risk per trade
    risk = 1;
    
     
    // Fetch some symbol properties
    double lotStep = MarketInfo(Symbol(), MODE_LOTSTEP);
    double minLot  = MarketInfo(Symbol(), MODE_MINLOT); 
    double maxLot  = MarketInfo(Symbol(), MODE_MAXLOT);
    double tickVal = MarketInfo(Symbol(), MODE_TICKVALUE);
 
    // Calculate the actual lot size
    double lotSize = ((AccountBalance() * risk) / 100) / (stopLoss * tickVal);
    
    // This rounds the lotSize to the nearest lotstep interval
    lotSize = MathMin(maxLot, MathMax(minLot, NormalizeDouble(lotSize/lotStep, 0) * lotStep));

[CaneRandagio]

Md Atikur Rahman #:

This is how I calculate lot size

thanks for reply!

the fact is that in the operation

double maxRiskInPrice = accountBalance * (riskPercentage / 100);

it returns me 0. it be

 maxRiskInPrice = 9500 * (5 / 100)  = 0

it does not make sense

[Dominik Egert]

It does make sense. You are using integers.

5 / 100 = 0;

While with double:

5.0 / 100.0 = 0.05;

[Haruto Rat]

CaneRandagio:

Where is the mistake?

Typecasting, sir!

(pay special attention to the examples there)

[William Roeder]

1. Of course, it does.
             On MT4 v434, division quotient don't give floating point values(Bug??) - MQL4 programming forum (2012)
             build 2504 & 2506 Bug - General - MQL5 programming forum - Page 2 #17 (2020.07.03)

2. Risk depends on your initial stop loss, lot size, and the value of the symbol. It does not depend on margin and leverage. No SL means you have infinite risk. Never risk more than a small percentage of your trading funds, certainly less than 2% per trade, 6% total.

   1. You place the stop where it needs to be — where the reason for the trade is no longer valid. E.g. trading a support bounce, the stop goes below the support.

   2. AccountBalance * percent/100 = RISK = OrderLots * (|OrderOpenPrice - OrderStopLoss| * DeltaPerLot + CommissionPerLot) (Note OOP-OSL includes the spread, and DeltaPerLot is usually around $10/PIP but it takes account of the exchange rates of the pair vs. your account currency.)

   3. Do NOT use TickValue by itself - DeltaPerLot and verify that MODE_TICKVALUE is returning a value in your deposit currency, as promised by the documentation, or whether it is returning a value in the instrument's base currency.
                MODE_TICKVALUE is not reliable on non-fx instruments with many brokers - MQL4 programming forum (2017)
                Is there an universal solution for Tick value? - Currency Pairs - General - MQL5 programming forum (2018)
                Lot value calculation off by a factor of 100 - MQL5 programming forum (2019)

   4. You must normalize lots properly and check against min and max.

   5. You must also check FreeMargin to avoid stop out

   6. For MT5, see 'Money Fixed Risk' - MQL5 Code Base (2017)

   Most pairs are worth about $10 per PIP. A $5 risk with a (very small) 5 PIP SL is $5/$10/5 or 0.1 Lots maximum.

[CaneRandagio]

Dominik Christian Egert #:

It does make sense. You are using integers.

5 / 100 = 0;

While with double:

5.0 / 100.0 = 0.05;

Haruto Rat #:

Typecasting, sir!

(pay special attention to the examples there)

William Roeder #:

1. Of course, it does.
             On MT4 v434, division quotient don't give floating point values(Bug??) - MQL4 programming forum (2012)
             build 2504 & 2506 Bug - General - MQL5 programming forum - Page 2 #17 (2020.07.03)

2. Risk depends on your initial stop loss, lot size, and the value of the symbol. It does not depend on margin and leverage. No SL means you have infinite risk. Never risk more than a small percentage of your trading funds, certainly less than 2% per trade, 6% total.

   1. You place the stop where it needs to be — where the reason for the trade is no longer valid. E.g. trading a support bounce, the stop goes below the support.

   2. AccountBalance * percent/100 = RISK = OrderLots * (|OrderOpenPrice - OrderStopLoss| * DeltaPerLot + CommissionPerLot) (Note OOP-OSL includes the spread, and DeltaPerLot is usually around $10/PIP but it takes account of the exchange rates of the pair vs. your account currency.)

   3. Do NOT use TickValue by itself - DeltaPerLot and verify that MODE_TICKVALUE is returning a value in your deposit currency, as promised by the documentation, or whether it is returning a value in the instrument's base currency.
                MODE_TICKVALUE is not reliable on non-fx instruments with many brokers - MQL4 programming forum (2017)
                Is there an universal solution for Tick value? - Currency Pairs - General - MQL5 programming forum (2018)
                Lot value calculation off by a factor of 100 - MQL5 programming forum (2019)

   4. You must normalize lots properly and check against min and max.

   5. You must also check FreeMargin to avoid stop out

   6. For MT5, see 'Money Fixed Risk' - MQL5 Code Base (2017)

   Most pairs are worth about $10 per PIP. A $5 risk with a (very small) 5 PIP SL is $5/$10/5 or 0.1 Lots maximum.

ok! thanks guys!