Arithmetic: The Exponential of a Number 

double exp(double x); The exp() function calculates the exponential value of a number. The argument, a doubleprecision value, represents the number to be evaluated. If the value of x is less than 708.395996093 (approximately), the result is reset to 0 and qualifies as underflow. If the value of the argument x is greater than 709.78222656 (approximately), the result is INF and qualified as overflow: // #include <iostream.h> #pragma hdrstop // #pragma argsusedint main(int argc, char* argv[]) { cout << "\nThe exponential of " << 709.78222656 << " is " << exp(709.78222656); cout << "\n\nPress any key to continue..."; getchar(); return 0; } // Therefore, the value of the argument should be between these two extremes. For a larger number, use the expl() function: long double expl(long double x); As opposed to an 8byte value, this version of the function takes a 10byte variable, calculates its exponent, and returns a long double. 
Home  Copyright © 20042016, FunctionX, Inc.  