C++ floating point to integer type conversions

Question

What are the different techniques used to convert float type of data to integer in C++?

#include 

using namespace std;
struct database {
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Answer 1

Size of some float types may exceed the size of int. This example shows a safe conversion of any float type to int using the int safeFloatToInt(const FloatType &num); function:

#include 
#include 
using namespace std;

template 
int safeFloatToInt(const FloatType &num) {
   //check if float fits into integer
   if ( numeric_limits::digits < numeric_limits::digits) {
      // check if float is smaller than max int
      if( (num < static_cast( numeric_limits::max())) &&
          (num > static_cast( numeric_limits::min())) ) {
         return static_cast(num); //safe to cast
      } else {
        cerr << "Unsafe conversion of value:" << num << endl;
        //NaN is not defined for int return the largest int value
        return numeric_limits::max();
      }
   } else {
      //It is safe to cast
      return static_cast(num);
   }
}
int main(){
   double a=2251799813685240.0;
   float b=43.0;
   double c=23333.0;
   //unsafe cast
   cout << safeFloatToInt(a) << endl;
   cout << safeFloatToInt(b) << endl;
   cout << safeFloatToInt(c) << endl;
   return 0;
}

Result:

Unsafe conversion of value:2.2518e+15
2147483647
43
23333