Current Implementations

The GrADS Data Server (GDS)

Institution

The Center for Ocean-Land-Atmosphere Studies of the Institute for Global Environment and Society

Documentation

Overview and details about server-side processing.

Implementation Details

A Java Servlet implemented on top of the bespoke Anagram Framework using the Java Runtime environment to execute the GrADS application to perform the data access and analysis and using the Java OPeNDAP library for DAP communication.

Syntax

http://machine_name:9090/dods/_expr_ followed immediately by three sets of curly braces containing arguments, as follows:

{dataset1,dataset2,...}{expression}{x1:x2,y1:y2,z1:z2,t1:t2}

where the first set of braces contains a list of data sets to be used in the analysis, expression is any valid GrADS expression operating on the variables in the scope of the referenced data sets and the thirds set of braces is the boundaries for the evaluation of the expression in world coordinates.

Ingrid

Institution

The [Data Library] of the [The International Research Institute for Climate and Society]

Documentation

[Overview]

• [Function Menu]

Implementation Details

Local code not under wide distribution.

Functions

166 functions [detailed here].

Syntax

A URL-based (not in the query string) RPN notation.

For example:

http://iridl.ldeo.columbia.edu/expert/SOURCES/.NOAA/.NCEP/.CPC/.GMSM/.w/5/add/

SOURCES .NOAA .NCEP .CPC .GMSM .w (the OPeDNAP data variable)

5 add (the constant 5; the operation desired)

http://iridl.ldeo.columbia.edu/expert/SOURCES/.NOAA/.NCDC/.ERSST/.version2/.SST/X/(170W)(120W)RANGE/Y/(5S)(5N)RANGE[X/Y]average/ (The actual URL must be encoded. See the link contents.)

SOURCES .NOAA .NCDC .ERSST .version2 .SST (The OPeDNAP data variable)

X (170W) (120W) RANGE (A range in X of the data variable's underlying grid in world coordinates)

Y (5S) (5N) RANGE (A range in Y of the data variable's underlying grid in world coordinates)

[X Y]average (the dimensions to be operated on; the operation)

Benno -- Is there also an index notation for the ranges? If Y did not appear in the [X Y] then the average would be a line in Y from 5S to 5N, right?