Unit tests usually use functions, which assert something as part of the test. When doing numerical calculations, often we have the fundamental issue of trying to compare floating-point numbers that are almost equal. For integers, comparison is a trivial operation, but for floating-point numbers it is not, because of the inexact representation by computers. The NumPy testing package has a number of utility functions that test whether a precondition is true or not, taking into account the problem of floating-point comparisons. The following table shows the different utility functions: