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This function defines a level within the point. A simple point consists of a single level. A point where there is common data for a number of records can be more efficiently stored with multiple levels. The order in which the levels are defined determines the (0-based) level index.


See Additional Examples for more information on using EOS_PT_DEFLEVEL.

Example 1: Simple Point:

In this example, we define a simple single level point, with levelname, Sensor. The levelname should not contain any slashes (“/”). It consists of six fields, ID, Time, Longitude, Latitude, Temperature, and Mode defined in the field list. The fieldtype and fieldorder parameters are arrays consisting of the HDF number type codes and field orders, respectively. The Temperature is an array field of dimension 4 and the Mode field a character string of size 4. All other fields are scalars. Note that the order for numerical scalar variables can be either 0 or 1.

fieldtype = [22, 22, 5, 5, 5, 4]
fieldorder = [0,0,0,0,4,4]
fldlist = "ID,Time,Longitude,Latitude,Temperature,Mode"
status = EOS_PT_DEFLEVEL(pointID, "Sensor", fldlist, fieldtype,$ fieldorder)


Result = EOS_PT_DEFLEVEL(pointID, levelname, fieldlist, fieldtype, fieldorder)

Return Value




Point id (long) returned by EOS_PT_CREATE or EOS_PT_ATTACH.


Name of level (string) to be defined.


List of fields (string) in level.


Array (long) containing HDF data type of each field within level.


Array (long) containing order of each field within level.

Note: An order of 0 is considered the same as an order of 1.



Additional Examples

Example 2: Multi-Level Point:

In this example, we define a two-level point that describes data from a network of fixed buoys. The first level contains information about each buoy and includes the name (label) of the buoy, its (fixed) longitude and latitude, its deployment date, and an ID that is used to link it to the following level. (The link field is defined in the EOS_PT_DEFLINKAGE routine described later.) The entries within the ID field must be unique. The second level contains the actual measurements from the buoys (rainfall and temperature values) plus the observation time and the ID which relates a given measurement to a particular buoy entry in the previous level. There can be many records in this level with the same ID since there can be multiple measurements from a single buoy. It is advantageous, although not mandatory, to store all records for a particular buoy (ID) contiguously.

Level 0

fieldtype0 = [4, 6, 6, 5, 4]
fieldorder0 = [8,0,0,0,1]
fldlist0 =       "Label,Longitude,Latitude,DeployDate,ID"
status = EOS_PT_deflevel(pointID2, "Desc-Loc", $
   fldlist0, fieldtype0, fieldorder0)

Level 1

fieldtype1 = [6, 5, 5, 4]
fieldorder1 = [0,0,0,1]
fldlist1 = "Time,Rainfall,Temperature,ID"
status = EOS_PT_DEFLEVEL(pointID2, "Observations", $
   fldlist1, fieldtype1, fieldorder1)

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