Can a float be exactly 0?

Can a float be exactly 0?

Even though 0 has an exact representation, you can’t rely on the result of a calculation using floats to be exactly 0. As you noted, this is due to floating point calculation and conversion issues.

How do you know if a float is 0?

For example, we want to find out if a floating point number is equal to zero:

1. float f = sqrt(9.0f) – 3.0f; // 9²-3. if (f == 0.0f) // works only sometimes. { // equal. }
2. bool cmpf(float A, float B, float epsilon = 0.005f) { return (fabs(A – B) < epsilon); }
3. float f = sqrt(9.0f) – 3.0f; if (cmpf(f, 0.0f)) { // equal. }

Is it safe to compare float to zero?

It is not safe (because it is not correct) to expect that the result of some calculation will be zero in double (or more generally, floating point) arithmetics whenever the result of the same calculation in pure Mathematics is zero.

Is 0 a float or int?

Introduction to integersEdit An integer, commonly abbreviated to int, is a whole number (positive, negative, or zero). So 7 , 0 , -11 , 2 , and 5 are integers. 3.14159 , 0.0001 , 11.11111 , and even 2.0 are not integers, they are floats in Python.

How does float compare in C++?

To compare two floating point values, we have to consider the precision in to the comparison. For example, if two numbers are 3.1428 and 3.1415, then they are same up to the precision 0.01, but after that, like 0.001 they are not same.

How do you know if a double value is zero?

if(value != 0) //divide by value is safe when value is not exactly zero. Otherwise when checking if a floating point value like double or float is 0, an error threshold is used to detect if the value is near 0, but not quite 0.

What is a floating point in C++?

A floating point type variable is a variable that can hold a real number, such as 4320.0, -3.33, or 0.01226. The floating part of the name floating point refers to the fact that the decimal point can “float”; that is, it can support a variable number of digits before and after the decimal point.

Can you use == to compare floats?

Comparing for equality Floating point math is not exact. That means that comparing two floats to see if they are equal is usually not what you want. GCC even has a (well intentioned but misguided) warning for this: “warning: comparing floating point with == or !=

What is a float C++?

Float is a shortened term for “floating point.” By definition, it’s a fundamental data type built into the compiler that’s used to define numeric values with floating decimal points. C, C++, C# and many other programming languages recognize float as a data type. Other common data types include int and double.