4.6.3 Converting numbers

Sometimes it is desirable to convert a numeric object back to a built-in arithmetic type (int, double, etc.). The numeric class provides a couple of methods for this purpose:

int numeric::to_int() const;
long numeric::to_long() const;
double numeric::to_double() const;
cln::cl_N numeric::to_cl_N() const;

to_int() and to_long() only work when the number they are applied on is an exact integer. Otherwise the program will halt with a message like ‘Not a 32-bit integer’. to_double() applied on a rational number will return a floating-point approximation. Both to_int()/to_long() and to_double() discard the imaginary part of complex numbers.