Some common types of data

Objects

R is an object oriented programming language where you assign things to objects and it is similar to python, S, etc. Objects can be vectors, arrays, matrices, data frames, a single character string, functions, etc.

Data Structures - vectors, matrices, arrays, lists, and data frames

• Data contained as vectors, matrices, and arrays are homogeneous.
• Lists and data frames are heterogeneous.
• Indices start at 1, not 0.
• Each row is a single observation.
• Each column is a single variable of the same data type.

Vectors

• atomic: logical, integer, double, character, complex, raw
• lists: recursive vectors (you can have a list of lists)
• augmented vectors: factors, dates, date-times, tibbles

Arrays

Arrays are like vectors with a dimensional attribute.

Matrices

Matrices are like two dimensional arrays.

Data Frames (and Tibbles)

A data frame is a what one would commonly think of as a table (your typical spreadsheet) that consists of vectors. A tibble is a type of data frame that retains the data type (e.g. character, date, integer) for each attribute (column). Each variable within a data frame or tibble must be of equal length.

Lists

A data frame can be a list, but a list can not always be a data frame. Lists can be composed of a list of lists, or a list of data frames, where variables and data frames do not need to be of equal length.