The After Strife – a.k.

a.k. from thus spake a.k.

As well as required arithmetic operations, such as addition, subtraction, multiplication and division, the IEEE 754 floating point standard has a number of recommended functions. For example finite determines whether its argument is neither infinite nor NaN and isnan determines whether its argument is NaN; behaviours that shouldn't be particularly surprising since they're more or less equivalent to JavaScript's isFinite and isNaN functions respectively.
One recommended function that JavaScript does not provide, and which I should like to add to the ak library, is nextafter which returns the first representable floating point number after its first argument in the direction towards its second.