Anything I don't understand on MQL5

[arcenciel]

Hi guys

Why DoubleToString(40/26,3) give me the string 1.000 ? Normally it's 1.538
If I do :
double test = 40/26;
DoubleToString(test,3) it give me also 1.000 and not 1.538

[Vladimir Karputov]

arcenciel:

Hi guys

Why DoubleToString(40/26,3) give me the string 1.000 ? Normally it's 1.538
If I do :
double test = 40/26;
DoubleToString(test,3) it give me also 1.000 and not 1.538

Test:

//+------------------------------------------------------------------+
//|                                                     Script 1.mq5 |
//|                        Copyright 2020, MetaQuotes Software Corp. |
//|                                             https://www.mql5.com |
//+------------------------------------------------------------------+
#property copyright "Copyright 2020, MetaQuotes Software Corp."
#property link      "https://www.mql5.com"
#property version   "1.00"
//---
//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+
void OnStart()
  {
   int int_a=40,int_b=26;
   double dbl_a=40.0,dbl_b=26.3;
   
   Print("int_a / dbl_b ",DoubleToString(int_a / dbl_b));
   Print("dbl_a / dbl_b ",DoubleToString(dbl_a / dbl_b));
   Print("int_a / int_b ",DoubleToString(int_a / int_b));
  }
//+------------------------------------------------------------------+

Result:

2021.02.16 13:02:01.325 Script 1 (EURUSD,H1)    int_a / dbl_b 1.52091255
2021.02.16 13:02:01.642 Script 1 (EURUSD,H1)    dbl_a / dbl_b 1.52091255
2021.02.16 13:02:01.939 Script 1 (EURUSD,H1)    int_a / int_b 1.00000000

Documentation:  Real Types (double, float)

[arcenciel]

Vladimir Karputov:

Test:

Result:

Documentation:  Real Types (double, float)

Hi Vladimir,

thank you for your reply
if I do like this it's ok :

double test=(double)40/26;
DoubleToString(test,3) gives me the string : 1.538 (40 and 26 are double numbers)

but if I do just
double test=40/26;
DoubleToString(test,3) gives me the string : 1.000 (40 and 26 are Integers numbers)

I had never take care about this before ...
Have a good Day

[William Roeder]

arcenciel: but if I do just

double test=40/26;
DoubleToString(test,3) gives me the string : 1.000 (40 and 26 are Integers numbers)

Of course it does.
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