5.9 A Convention for Coordinates: Coordinate Variables

Coordinate Variables contain the coordinate values for a dimension.

A variable with the same name as a dimension is called a ** coordinate
variable**. Many programs that read netCDF files recognize and use
any coordinate values they find.

To be useful for defining a coordinate system, a coordinate variable should:

- be one-dimensional
- specify the coordinate value corresponding to each dimension index
- contain no missing values
- have values that are strictly increasing or strictly decreasing

The notion of coordinate variables has been generalized to
multidimensional ** coordinate axes** and sets of coordinate axes
that comprise