Calculating volume for sphere in C++
This is probably an easy one, but is the right way to calculate volume for a sphere in C++? My getArea() seems to be right, but when I call getVolume() it doesn't output the right amount. With a sphere of radius = 1, it gives me the answer of pi, which is incorrect:
double Sphere::getArea() const
{
return 4 * Shape::pi * pow(getZ(), 2);
}
double Sphere::getVolume() const
{
return (4 / 3) * Shape::pi * pow(getZ(), 3);
}
You're using integer division in (4 / 3). Instead, use floating point division: (4.0 / 3.0).
4/3 is 1, because integer division only produces integers. You can confirm this by test code: std::cout << (4/3) << std::endl;.
In (4 / 3), these are both integers so you get integer division. That means the result will be truncated (1.333... becomes 1). Make one of them a double so the other gets promoted to a double during division, yielding a correct result.
I prefer to use (4.0 / 3.0).
(4 / 3) is an integer expression and is therefore being truncated to 1. Try (4.0 / 3.0)
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