31:, and its current specification is DAP4, though the previous DAP2 version remains broadly used. Developed and advanced (openly and collaboratively) by the non-profit OPeNDAP, Inc., DAP is intended to enable remote, selective data-retrieval as an easily invoked Web service. OPeNDAP, Inc. also develops and maintains zero-cost (reference) implementations of the DAP protocol in both server-side and client-side software.
34:"OPeNDAP" often is used in place of "DAP" to denote the protocol but also may refer to an entire DAP-based data-retrieval architecture. Other DAP-centered architectures, such as THREDDS and ERDDAP, the NOAA GEO-IDE UAF ERDDAP exhibit significant interoperability with one another as well as with systems employing OPeNDAP's own (open-source) servers and software.
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by requests for metadata describing the structure and other details about the referenced data set. With this information, the client may construct DAP constraint expressions to retrieve specific content (i.e., subsets) from the source. OPeNDAP servers offer various types of responses, depending on
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data, including satellite imagery and other high-volume information sources. The DAP data model embraces a comprehensive set of data structures, including multidimensional arrays and nested sequences (i.e., records), complemented by a correspondingly rich set of constraint expressions. Hence the
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23:," an endeavor focused on enhancing the retrieval of remote, structured data through a Web-based architecture and a discipline-neutral Data Access Protocol (DAP). Widely used, especially in
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or NetCDF files, but the source data can exist in databases or other formats, including user-defined ones. When source data are organized as files, DAP retrievals enable, via
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or DAP-native encoding. (These binary forms offer compact means to deliver large volumes of content, and the DAP-native form may even be streamed if desired.)
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by its URL and requests metadata or content by issuing (usually through an embedded DAP library) an HTTP request to a DAP server. Content requests usually are
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301:- netCDF Explorer is multi-platform graphical browser for netCDF files. netCDF Explorer can browse files locally or remotely, by means of OPeNDAP
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Regardless of their types, and whether developed commercially or by an end-user, clients almost universally link to DAP servers through
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A DAP client can be an ordinary browser or even a spreadsheet, though with limited functionality (see OPeNDAP's Web page on
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that facilitate serving a wide variety of source data. DAP servers most frequently enable (remote) access to (large)
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that implement the DAP2 or DAP4 protocol in one language or another. OPeNDAP offers open-source libraries in
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ncBrowse - Java viewer for OPeNDAP netCDF files (supports wide range of netCDF conventions)
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55:Panoply
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