NetCDF Primer

The purpose of the Network Common Data Form (netCDF) interface is to allow you to create, access, and share scientific data in a form that is self-describing and network-transparent. "Self-describing" means that a file includes information defining the data it contains. "Network-transparent" means that a file is represented in a form that can be accessed by computers with different ways of storing integers, characters, and floating-point numbers. Using the netCDF interface for creating new scientific data sets can improve the accessibility of the data. Using the netCDF interface in new software for scientific data access, management, analysis, and display can improve the reusability of the software for other data sets and by other users. NetCDF is an abstraction that supports a view of data as a collection of self-describing, network-transparent objects that can be accessed through a simple interface. Collections of named multidimensional variables can be randomly accessed, without knowing details of how the data are stored. Auxiliary information about the data, such as what units are used, can be stored with the data. Generic utilities and application programs can be written that access arbitrary netCDF files and transform, combine, analyze, or display specified fields of the data. The development of such applications may lead to improved accessibility of data and improved reusability of software for scientific data management, analysis, and display.

The netCDF software implements an abstract data type, which means that all operations to access and manipulate data in a netCDF file must use only the set of functions provided by the interface. The actual representation of the data is hidden from applications that use the interface, so that how the data are stored could be changed without affecting such programs. The physical representation of netCDF data is designed to be independent of the computer on which the data were written.