how do you calculate the degrees of freedom?

The degrees of freedom is a measure of how many independent variables are in a system. The degrees of freedom for a system can be calculated by subtracting the number of equations that define the system from the number of variables involved in the system. For example, if a system had three variables and two equations, the degrees of freedom would be one. This is because there are three variables, but only two equations restricting their possible values, and thus there is one degree of freedom remaining.