Either true or false (the name comes from the mathematician George Boole).
Every column of a table contains zero or more rows
and is referred to by its column name.
In statistics a column is a variable that has been observed or measured,
but we prefer the term “column” to avoid confusion with variables in programming languages.
Every column in a table must have a distinct name
(though columns in different tables can have the same names).
A column name must start with the underscore ‘_’ or a letter,
and may only contain underscores, letters, and digits.
TidyBlocks automatically creates names for some columns,
such as _group_ for the column containing group IDs.
A moment in time represented by years, months, days, hours, minutes, and seconds.
Datetimes are always stored in Universal Time Coordinates,
and are also referred to as timestamps.
Datetimes are written as “YYYY-MM-DD:hh:mm:ss”.
Something that performs an operation to produce a value.
Expressions can be combined to create new expressions:
the expression (temperature - 32) * (5 / 9) uses multiplication
to combine two smaller expressions that use subtraction and division.
A subset of the rows in a table
that have the same values in one or more columns.
TidyBlocks gives each group a unique group ID.
The unique identifier for a group in a table.
TidyBlocks automatically stores group IDs in a column called _group_.
The standard time from which timezones are measured.
Often abbreviated “UTC”.
A single piece of data in a specific row and column of a table.
Every value has a type,
and some operations only work on some types of values.
In statistics, something that has been observed or measured.
Variables correspond to columns in tables;
we often use the term “column” to avoid confusion with
the idea of a variable in a programming language.