MT4 Coding Help Needed, Please see the snippets

[paulcarissimo]

Hi, I've been writing a multicurrency indicator in mql4 and I'm facing a challenge currently. the main error I get is a "divide by zero" but I'm having a hard time figuring out its source, please see the code below.

First the code that works;

1. This function receives currency pair arrays which have data from all time frames and also determines negative or positive correlation

Code: Select all

void CSMTFStrenght(bool one_isneg,
                   bool two_isneg,
                   bool three_isneg,
                   bool four_isneg,
                   bool five_isneg,
                   bool six_isneg,
                   bool seven_isneg,
                   double &c_mtf_str_main[],
                   double &c_mtf_str_up[],
                   double &c_mtf_str_down[],
                   double &one_up[],
                   double &two_up[],
                   double &three_up[],
                   double &four_up[],
                   double &five_up[],
                   double &six_up[],
                   double &seven_up[],
                   double &one_down[],
                   double &two_down[],
                   double &three_down[],
                   double &four_down[],
                   double &five_down[],
                   double &six_down[],
                   double &seven_down[],
                   double &mtf_str_main_pre[],
                   int main_limit,
                   int shift)
{
//--- tally all timeframes

    for (int i = 0; i <= 8; i++)
    {
        c_mtf_str_up[i]   = one_up[i] + two_up[i] + three_up[i] + four_up[i] + five_up[i] + six_up[i] + seven_up[i];
        c_mtf_str_down[i] = one_down[i] + two_down[i] + three_down[i] + four_down[i] + five_down[i] + six_down[i] + seven_down[i];
    }



//--- compare and send highest to main mtf strenght buffer
    for (int i = 0; i <= 8; i++)
        CSMTFCompare(c_mtf_str_main, c_mtf_str_up, c_mtf_str_down, i, mtf_str_main_pre, main_limit, shift);
   
}


2. This function compares if up or down is stronger and sends the info to the main currency strength buffers "c_mft_str_main"

Code: Select all

void  CSMTFCompare(double &out_buffer[],
                   double &a[],
                   double &b[],
                   int index,
                   double &out_buffer_pre[],
                   int main_limit,
                   int shift)
{
    if (a[index] > b[index])
    {
        out_buffer[index] = a[index];
    }                                                  // up wins
    else if (a[index] < b[index])
    {
        out_buffer[index] = b[index];
    }                                                       // down wins
    else if (a[index] == b[index])
    {
        out_buffer[index] = a[index];
    }                                                 // even
    out_buffer[index]     = EMA(main_limit, out_buffer[index], main_limit - 1, CurrenyStrPeriod, shift);
    out_buffer_pre[index] = EMA(main_limit, out_buffer[index], main_limit - 1, CurrenyStrPeriod, shift - 2);
}

3. The modification, I had to factor in pairs that are negatively correlated so I wrote this function which brought all the problems

Code: Select all

double NegPairMTF(double &up[], double &down[], int index, bool isneg = false, bool isup = false, bool isdown = false)
{
    double strenght = 0.0;

    if (isneg == true)
    {
        if (up[index] > down[index])
        {
            strenght = down[index];
        }
        if (up[index] < down[index])
        {
            strenght = up[index];
        }
        if (up[index] == down[index])
        {
            strenght = up[index];
        }
    }
    else
    {
        if (isup == true && isdown == false)
        {
            strenght = up[index];
        }
        if (isup == false && isdown == true)
        {
            strenght = down[index];
        }
    }
    return strenght;
}

4. The first function is modified as this

Code: Select all

void CSMTFStrenght(bool one_isneg,
                   bool two_isneg,
                   bool three_isneg,
                   bool four_isneg,
                   bool five_isneg,
                   bool six_isneg,
                   bool seven_isneg,
                   double &c_mtf_str_main[],
                   double &c_mtf_str_up[],
                   double &c_mtf_str_down[],
                   double &one_up[],
                   double &two_up[],
                   double &three_up[],
                   double &four_up[],
                   double &five_up[],
                   double &six_up[],
                   double &seven_up[],
                   double &one_down[],
                   double &two_down[],
                   double &three_down[],
                   double &four_down[],
                   double &five_down[],
                   double &six_down[],
                   double &seven_down[],
                   double &mtf_str_main_pre[],
                   int main_limit,
                   int shift)
{
//--- tally all timeframes

    for (int i = 0; i <= 8; i++){
   
       
        c_mtf_str_up[i]=NegPairMTF(one_up,one_down,i,one_isneg,true,false) +
                        NegPairMTF(two_up,two_down,i,two_isneg,true,false) +
                        NegPairMTF(three_up,three_down,i,three_isneg,true,false) +
                        NegPairMTF(four_up,four_down,i,four_isneg,true,false) +
                        NegPairMTF(five_up,five_down,i,five_isneg,true,false) +
                        NegPairMTF(six_up,six_down,i,six_isneg,true,false) +
                        NegPairMTF(seven_up,seven_down,i,seven_isneg,true,false);
                       
        c_mtf_str_down[i]=NegPairMTF(one_up,one_down,i,one_isneg,false,true) +
                        NegPairMTF(two_up,two_down,i,two_isneg,false,true) +
                        NegPairMTF(three_up,three_down,i,three_isneg,false,true) +
                        NegPairMTF(four_up,four_down,i,four_isneg,false,true) +
                        NegPairMTF(five_up,five_down,i,five_isneg,false,true) +
                        NegPairMTF(six_up,six_down,i,six_isneg,false,true) +
                        NegPairMTF(seven_up,seven_down,i,seven_isneg,false,true);

           }



//--- compaire and send highest to main mtf strenght buffer
    for (int i = 0; i <= 8; i++)
        CSMTFCompare(c_mtf_str_main, c_mtf_str_up, c_mtf_str_down, i, mtf_str_main_pre, main_limit, shift);
   
}

5. I have another function that receives all this data but it creates a divide by zero error,which is ridiculous, please help!

[TheRumpledOne]

Upload the indicator in entirety and perhaps I can figure out the error.

Also, look in the journal, I think it will tell you what line caused the error.

I don't even see a divide in your code!!

[paulcarissimo]

Upload the indicator in entirety and perhaps I can figure out the error.

Also, look in the journal, I think it will tell you what line caused the error.

I don't even see a divide in your code!!

This is the code where the zero divide occurs, this code receives the output of "CSMTFStrenght" and expresses it as a percentage

Code: Select all

string CSSort(double current_Str, double pre_Str, double strenght_up, double strenght_down)
{
    string retString      = "";
    double total_strenght = strenght_up + strenght_down;
    double _up            = strenght_up / total_strenght * 100;
    double _down          = strenght_down / total_strenght * 100;
    if (strenght_up > strenght_down)
        retString = DoubleToString(_up, 1) ;//+ PME(current_Str, pre_Str);                 
    if (strenght_up < strenght_down)
        retString = DoubleToString(_down, 1);// + PME(current_Str, pre_Str);             
    if (strenght_up == strenght_down)
        retString =DoubleToString(_down, 1);// "EVEN";
    return retString;
}


However, the problem is not the function above, but this one below;

Code: Select all

 for (int i = 0; i <= 8; i++){
   
       
        c_mtf_str_up[i]=NegPairMTF(one_up,one_down,i,one_isneg,true,false) +
                        NegPairMTF(two_up,two_down,i,two_isneg,true,false) +
                        NegPairMTF(three_up,three_down,i,three_isneg,true,false) +
                        NegPairMTF(four_up,four_down,i,four_isneg,true,false) +
                        NegPairMTF(five_up,five_down,i,five_isneg,true,false) +
                        NegPairMTF(six_up,six_down,i,six_isneg,true,false) +
                        NegPairMTF(seven_up,seven_down,i,seven_isneg,true,false);
                       
        c_mtf_str_down[i]=NegPairMTF(one_up,one_down,i,one_isneg,false,true) +
                        NegPairMTF(two_up,two_down,i,two_isneg,false,true) +
                        NegPairMTF(three_up,three_down,i,three_isneg,false,true) +
                        NegPairMTF(four_up,four_down,i,four_isneg,false,true) +
                        NegPairMTF(five_up,five_down,i,five_isneg,false,true) +
                        NegPairMTF(six_up,six_down,i,six_isneg,false,true) +
                        NegPairMTF(seven_up,seven_down,i,seven_isneg,false,true);
                       
                 
           }



For proprietary reasons, I cant upload the full code , its not the code, but the algorithm.

[paulcarissimo]

Okay, I think I figured it out, however Id like to see your solution anyway.
Thanks for your time TRO!

[TheRumpledOne]

Okay, I think I figured it out, however Id like to see your solution anyway.
Thanks for your time TRO!

Proper coding is:

IF DENOMINATOR <> 0 THEN DIVIDE ELSE *ERROR DENOMINATOR IS ZERO*

Failure to code in this way can crash critical systems while you are asleep causing you to be awakened by a frantic caller.

[paulcarissimo]

Okay, I think I figured it out, however Id like to see your solution anyway.
Thanks for your time TRO!

Proper coding is:

IF DENOMINATOR <> 0 THEN DIVIDE ELSE *ERROR DENOMINATOR IS ZERO*

Failure to code in this way can crash critical systems while you are asleep causing you to be awakened by a frantic caller.

I'm aware of this workaround, I would have used it and not asked for help but the point is that the functions never return a zero value. This only happened after using the "NegPairMTF" function. In any case , thanks for your help TRO

[TheRumpledOne]

Okay, I think I figured it out, however Id like to see your solution anyway.
Thanks for your time TRO!

Proper coding is:

IF DENOMINATOR <> 0 THEN DIVIDE ELSE *ERROR DENOMINATOR IS ZERO*

Failure to code in this way can crash critical systems while you are asleep causing you to be awakened by a frantic caller.

I'm aware of this workaround, I would have used it and not asked for help but the point is that the functions never return a zero value. This only happened after using the "NegPairMTF" function. In any case , thanks for your help TRO

NEVER SAY NEVER WHEN CODING!!

You ALWAYS test. The alternative is to get a frantic call that the system crashed when you are asleep.

[paulcarissimo]

Proper coding is:

IF DENOMINATOR <> 0 THEN DIVIDE ELSE *ERROR DENOMINATOR IS ZERO*

Failure to code in this way can crash critical systems while you are asleep causing you to be awakened by a frantic caller.

I'm aware of this workaround, I would have used it and not asked for help but the point is that the functions never return a zero value. This only happened after using the "NegPairMTF" function. In any case , thanks for your help TRO

NEVER SAY NEVER WHEN CODING!!

You ALWAYS test. The alternative is to get a frantic call that the system crashed when you are asleep.

LOL TRO, I get the point , that's a very big font size

[perryhart]

OK, I think I get it.

Thanks!

[garima48]

Thanks for sharing this information