ios - NSString stringWithFormat cant set precision for exponential record -

i'm trying display small double value on textfield. example, docalculationforequalpressed function returns 0.00008, when display on text field shows exponential record (8e-05). don't need number shown in exponential view. how set precision when use exponential record ???

using specifier %.9g - doesn't help.

double result; result = [self.brain docalculationforequalpressed:[self.brain operationarray]];  if (result == infinity || result == -infinity || isnan(result)){     nsstring *infinity = @"\u221e";     self.displayfield.text = [nsstring stringwithformat:@"%@", infinity]; } else     self.displayfield.text = [nsstring stringwithformat:@"%.9g", result]; 

it can't done format specifier default.

you need use sprintf , remove trailing zeros yourself.

char str[50]; sprintf (str,"%.20g",num);  // make number. morphnumericstring (str, 3);  void morphnumericstring (char *s, int n) {     char *p;     int count;      p = strchr (s,'.');         // find decimal point, if any.     if (p != null) {         count = n;              // adjust more or less decimals.         while (count >= 0) {    // maximum decimals allowed.              count--;              if (*p != '\0')    // if there's less desired.                  break;              p++;               // next character.         }          *p-- = '\0';            // truncate string.         while (*p == '0')       // remove trailing zeros.             *p-- = '\0';          if (*p == '.') {        // if decimals zeros, remove ".".             *p = '\0';         }     } } 

see answer

https://stackoverflow.com/a/277810/569497