The connections component prescribes to DX how to perform interpolation between neighbouring grid elements. It describes the logical connectivity between adjacent neighbours in a grid. For example, the interpolation could be performed linearly along one of the axes, or bi- or tri-linearly along two or more axes simultaneously.
The connections component is implemented as an array. Each point in the positions component is given an ordinal number (starting at zero). The connections array comprises a `list of lists' of numbers in which each entry represents the ordinal values of the points that are to be connected, listed in the order that they are to be connected.
You will not normally need to be concerned with the full details of the connections component. For a regular grid it can be created automatically when the data are imported into DX and represented compactly using a path or mesh array.
Fields representing particle or catalogue data where there are no
logical connections between elements in the positions component will
not usually have a connections component (again think of the example
where each point represents a star orbiting in a globular cluster).
The DX Cookbook