A 1-dimensional data set is a structure in which each of the constituent elements is measured and indexed along a single dimension. The 1-dimensional data set, also known as a 1-dimensional array, is the archetypical subject of many foundational quantitative analytic techniques. For example, it is the simplest type of data set on which to perform frequency analysis, a powerful investigatory tool. Useful cleaning and filtering techniques can also be applied to rid 1-dimensional data of misleading systematic errors. As usual, I’ll discuss situations where these techniques are appropriate, as well as some common ways they are misused.