OPeNDAP User Guide
Version 1.14

This document describes version 3.2 of the Distributed Oceanographic Data System (OPeNDAP), a data system intended to allow researchers transparent access to oceanographic data--stored in any of several different file formats--across the Internet. Using OPeNDAP function libraries, many existing data analysis programs can be easily modified to accommodate access of distant datasets in a manner identical to the access of local datasets. OPeNDAP includes a protocol for the transmission of data across the Internet, and supports selection of data using constraint expressions, and translation of data from one format to another.

An overview of the system's use is presented, and specific tasks illustrated, for data providers as well as for users.

• Preface
  • 0.1 Tasks Illustrated in this Guide
  • 0.2 Who is this Guide for?
  • 0.3 Organization of this Document
  • 0.4 Conventions
• A Overview
  • 1 What is OPeNDAP?
    • 1.1 Why Use OPeNDAP to Read Data?
      • 1.1.1 An Example: Using ftp
      • 1.1.2 An Example: Using OPeNDAP
      • 1.1.3 The OPeNDAP Client
    • 1.2 Providing Data with OPeNDAP
      • 1.2.1 The OPeNDAP Server
      • 1.2.2 Ancillary Data
      • 1.2.3 Administration and Centralization of Data
• B Using OPeNDAP to Read Data
  • 2 Using OPeNDAP
    • 2.1 How OPeNDAP Finds Data
      • 2.1.1 Security
    • 2.2 The OPeNDAP Services
      • 2.2.1 WWW Interface
    • 2.3 Using an OPeNDAP Program
      • 2.3.1 Requirements
      • 2.3.2 Environment Variables
      • 2.3.3 The Error System
      • 2.3.4 Temporary Files
  • 3 The OPeNDAP Client
    • 3.1 Configuring Programs to Use OPeNDAP
      • 3.1.1 An Example Using netCDF
      • 3.1.2 Potential Problems
    • 3.2 Writing New OPeNDAP Programs
  • 4 Data Analysis with OPeNDAP
    • 4.1 Selecting Data: Using Constraint Expressions
      • 4.1.1 Constraint Expression Syntax
      • 4.1.2 Operators, Special Functions, and Data Types
      • 4.1.3 Using Functions in a Constraint Expression
      • 4.1.4 Using URLs in a Constraint Expression
      • 4.1.5 Pattern Matching with Constraint Expressions
      • 4.1.6 Optimizing the Query
    • 4.2 A Word About Data Translation
• C Providing Data with DODS
  • 5 The OPeNDAP Server
    • 5.1 Server Architecture
      • 5.1.1 Service Programs
    • 5.2 Installing an OPeNDAP Server
      • 5.2.1 Configuring the Server
      • 5.2.2 Constructing the URL
      • 5.2.3 Documenting Your Data
      • 5.2.4 Testing the Installation
    • 5.3 Displaying Information to the OPeNDAP User
      • 5.3.1 GUI Architecture
    • 5.4 Building OPeNDAP Data Servers
• D Technical Documentation
  • 6 Data and Data Models
    • 6.1 Data models
      • 6.1.1 Data Models and APIs
      • 6.1.2 Translating Data Models
    • 6.2 Data Access Protocol
    • 6.3 Data representation
      • 6.3.1 Base Types
      • 6.3.2 Constructor Types
      • 6.3.3 Operators
      • 6.3.4 External Data Representation
    • 6.4 Ancillary data
      • 6.4.1 Dataset Descriptor Structure
      • 6.4.2 Dataset Attribute Structure
• E Appendices
  • A Installing the OPeNDAP Software
    • A.1 Acquiring the OPeNDAP Software
    • A.2 Installing the Software
      • A.2.1 Installing the OPeNDAP Libraries
    • A.3 The OPeNDAP Client Initialization File (.dodsrc)
  • B Software you will need for DODS
    • B.1 Running an OPeNDAP Server
    • B.2 Running an OPeNDAP Client
    • B.3 Building DODS
  • Glossary
  • References
  • Index
• Footnotes