Development Page--Not for Official Use

This page needs editing to consolidate all three sections

Each station has an attribute called class that is treated specially from all of the other attributes. When an attribute is added in stnattr, normally it replaces whatever value that attribute had before. For each new class attribute the value is concatenated to the existing value. In order to remove classes, the value needs to be preceded with a !. Another aspect of values that may appear in the class attribute is that they are delimited with colons. For example, if you wished to remove a station from the class pf stations that are to be QCed, you would add a new attribute (via http://lighthouse.tamucc.edu:4001/stnattr ) with a value of :!qc:.

Here's a description of the classes we use in the class attribute and their intended meanings.

• :active: - The station is supposed to be active.
• :cbi: - The station is "owned" by DNR (should this attribute be :dnr: instead?)
• :ccrtns: - The station is part of the Corpus Christi Real Time Navigation System
• :comps: - The station is a COMPS station
• :dl: - The station represents a downloading site
• :dorpt: - The station will be part of the DO report
• :hydro: - The station has a hydrolab installed
• :ndbc: - The station is an NDBC station
• :noaa: - The station is a NOAA station
• :qc: - The station is one that appears in the QC list
• :tabs: - The station is a TABS station
• :tcoon: - The station is part of the TCOON Network
• :wavcis: - The station is a WAVCIS station

From DNRDocs.ClassNotation:

Station Specifications

Class names are specified in the class attribute of the station attribute table. Here is a non-exhaustive list of various classes and their meanings:

• The last entry in the table above can be performed for any series, such as water temperature (wtp), barametric pressure (bpr), etc.

Imposing Conditions upon Classes

There are several ways to impose conditions upon classes. Let 'class' stand for whatever class you would like to use, such as active, tcoon, pwl, wtp, etc.

Negation

As noted above, in order to involve stations of a certain class, use the ':class:' notation. In order to negate this class and therefore involve all stations not of this class, use the ':!class:' notation.

And

To combine classes in an AND relationship, use the ':class1:class2:class3:' notation. This will involve stations that belong to all classes listed which in this case would be class1, class2 and class3.

Or

To combine classes in an OR relationship, use the ':class1:,:class2:,:class3:' notations. Note the commas separating the individual colon-enclosed class names. This will involve all stations belonging to any of the classes listed which in this case would be either class1, class2 or class3 or any combination thereof.

Syntax

Class notations may be used in an internet browser window using the following syntax:

• http://lighthouse.tamucc.edu/qc/:classname:

They may also be used in programs as follows:

• my @stnids = PDB::IdList^?(time, ':active:');

Additional Notes

• Stations may have more than one class. For example, a station could have the class attribute of ':active:tcoon:' which would mean it is both an active station and a TCOON station.

• Any attribute is implicitly a class specifier. For example, using :freewave: as a class specifier will involve all stations who's data is transmitted by freewave radio.

• Class specifiers are time dependent. If a time is not specified within a query, the default time of 'now' is used. For example, if you do not specify a time and use the :pwl: attribute, you will involve all stations collecting water level at this moment in time only. If there were a station which use to collect water level but for some reason does not now, it will not be included in this query.

Class specifications viewed as set operations

I drew these diagrams to serve as guidelines while we were developing the new database back-end station attributes/classes code. Click on the image for a larger version.

From DNRDocs.StationAttributes:

Special station class attribute values and their meanings:

 
cbi	station is owned/operated by cbi
tcoon	station is a TCOON station
comps   station is a Florida COMPS station
tabs    station is a TABS station
ccrtns	station is a Port of CC RTNS station
wavcis	station is a Louisiana WAVCIS station
ndbc	station is a National Data Buoy Center station
qc	station is on the qc list
nws     station is a National Weather Service
nueces  station is part of the Nueces Bay Salinity project
hydro	station contains a Hydrolab