Double condition ( "OR" in MQL4)

Massimo 2016.04.10 15:02

Hello to all. I need help to find out if the code I wrote is right or not.
I wrote this code to mean that the condition is valid if I cross the RSI at level 50.

.....

 if(iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i) < 50
 && iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i+1) > 50
 &&............

I would like to add an additional condition which is valid if the RSI cross the level 50 "OR" if the RSI is below the 10 level.

I wrote this code but I would like to know from the experts if it is correct:

.....

 if((iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i) < 50 + iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i+1) > 50 || iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i) < 10)
 &&............

Thank you all, Massimo.

Alain Verleyen 2016.04.10 15:20 #1

omissamf:
Hello to all. I need help to find out if the code I wrote is right or not.
I wrote this code to mean that the condition is valid if I cross the RSI at level 50.

I would like to add an additional condition which is valid if the RSI cross the level 50 "OR" if the RSI is below the 10 level.

I wrote this code but I would like to know from the experts if it is correct:

Thank you all, Massimo.

It's not correct. You need to use && and parentheses :

double current    = iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i);
double previous   = iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i+1);

if(((current<50 && previous>50) || current<10)
   && ...
   )
  {
    ...
  }

Massimo 2016.04.10 15:33 #2

Thanks, angevoyageur.

But I could also write:

.....

 if((iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i) < 50 && iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i+1) > 50 || iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i) < 10)
 &&............

or is it really wrong?

Massimo.

Carl Schreiber 2016.04.10 15:57 #3

Let it become your habit if you mix && and || always use parentheses!

in your case you open 2 '(' and don't close them but - what do you want (?):

a) iRSI(1) && ( iRSI(2) || iRSI(3) ) && iRSI(4) ... or

b) (iRSI(1) && iRSI(2) ) || ( iRSI(3) && iRSI(4) ) ...

Questions from Beginners MQL5 Wrong RSI on my MT4/MT5 data flow

Alain Verleyen 2016.04.10 16:00 #4

omissamf:
Thanks, angevoyageur.

But I could also write:

or is it really wrong?

Massimo.

It's not the same. Please read the documentation about precedence rules.

William Roeder 2016.04.10 17:28 #5

gooly: Let it become your habit if you mix && and \|\| always use parentheses!	Always use parentheses when mixing ands and ors. Or make your code readable. double current = iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i); double previous = iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i+1); bool wasAbove = previous > 50; bool isAbove = current > 50; bool hasCrossed = isAbove != wasAbove; if(hasCrossed){ ... }

gooly: Let it become your habit if you mix && and || always use parentheses!

Always use parentheses when mixing ands and ors.

Or make your code readable.

double current    = iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i);
double previous   = iRSI(NULL, PERIOD_CURRENT, 2, PRICE_CLOSE, i+1);

bool wasAbove = previous > 50;
bool  isAbove =  current > 50;
bool hasCrossed = isAbove != wasAbove;

if(hasCrossed){ ... }

Massimo 2016.04.10 18:48 #6

Thank you all.

I understood.

Greetings, Massimo.

New comment