C++ (Cpp) Rational::to_double示例

#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN

#include <Rational.h>
#include <doctest.h>

#include <limits>

SCENARIO( "convert a rational to a double") {
  //      CHECK (275 == doctest::Approx(actual));
  GIVEN ("a valid rational number") {
    WHEN("the Rational is 0") {
      Rational<int> r {0};
      THEN( "the value should convert to 0" ) {
        REQUIRE (r.to_double() == 0);
        //REQUIRE (double(r) == 0);
      }
    }
    WHEN("the rational is 1/2") {
      Rational<int> r {1,2};
      THEN( "the value should convert to 0.5" ) {
        REQUIRE (r.to_double() == doctest::Approx(0.5));
        //REQUIRE (double(r) == doctest::Approx(0.5));
      }
    }
    WHEN("the rational is {-22,7}") {
      Rational<int> r {-22,7};
      THEN( "the value should convert to -pi" ) {
        REQUIRE (r.to_double() == doctest::Approx(-3.14).epsilon(0.01));
        //REQUIRE (double(r) == doctest::Approx(-3.14).epsilon(0.01));
      }
    }

示例#2

显示文件

文件： main.cpp 项目： devtype-blogspot-com/CPP-Examples

bool operator <( Rational const & a , Rational const & b ) {
    return a.to_double() < b.to_double();
}