SingleValueMetric-class {IRISMustangMetrics}

Class "SingleValueMetric"

Description

A container for metrics results and associated metadata. This information is used to create XML that is then submitted to the MUSTANG Backend Storage System (BSS). This has been superceded by GeneralValueMetric and is no longer in use.

Objects from the Class

Objects can be created by calls of the form:

new("SingleValueMetric", snclq, starttime, endtime, metricName, value)

Lists of SingleValueMetric objects are returned by various metrics functions in this package.

Slots

snclq:

Object of class "character": SNCLQ identifier.

metricName:

Object of class "character": Name of the metric.

starttime:

Object of class "POSIXct": Start time.

endtime:

Object of class "POSIXct": End time.

valueName:

Object of class "character": Name of the XML value identifier (default="value").

value:

Object of class "numeric": Metric value.

valueString:

Object of class "character": String representation of the metric value.

quality_flag:

Object of class "numeric": Quality flag.

quality_flagString:

Object of class "character": String representation of quality flag.

attributeName:

Object of class "character": Name of one or more optional attributes.

attributeValueString:

Object of class "character": String representation of one or more attribute values.

Methods

show

signature(object = "SingleValueMetric"): Prettyprints the information in the SingleValueMetric

Note

The starttime and endtime slots are typically associated with the user requested times which may not match up with the starttime associated with the first Trace and the endtime associated with last Trace in the Stream object being analyzed. This ensures that metrics results for a single time period but covering many stations or channels will have the same date range and improves performance of the BSS which expects XML of the following form:

<measurements>
  <date start='2012-02-10T00:00:00.000' end='2012-02-10T09:20:00.000'>
    <target snclq='N.S.L.C1.Q'>
      <example value='1.0'/>
    </target>
    <target snclq='N.S.L.C2.Q'>
      <example value='2.0'/>
    </target>
    <target snclq='N.S.L.C3.Q'>
      <example value='3.0'/>
    </target>
  </date>
  </date>
</measurements>

The quality_flag is an optional value available for storing information related to the processing of a particular metric. Its meaning will vary from metric to metric.

For an IRIS/DMC specific example, the station_completeness metric obtains a list of available channels for a station from the availability web service and compares this list with the list of percent_availability metrics for this station stored in the MUSTANG BSS. In the case of the station_completeness metric, the quality_flag is set to the number of channels that should be available but for whom no percent_availability measure is obtained form the BSS.

The attributeName and attributeValueString slots can be used to store additional attributes associated with a metric values. For example, the max_stalta value for a seismic trace can be calculated and a metric can be created that contains this value and another attribute with a string representation of the time at which this maximum occurred.

Author(s)

Jonathan Callahan [e-mail]

Examples

  ## Not run: 
# Open a connection to IRIS DMC webservices
iris <- new("IrisClient")

# Get the waveform
starttime <- as.POSIXct("2012-01-24", tz="GMT")
endtime <- as.POSIXct("2012-01-25", tz="GMT")
st <- getDataselect(iris,"AK","PIN","","BHZ",starttime,endtime)

# Apply a metric and show the results
metricList <- basicStatsMetric(st)
show(metricList[[1]])
  
## End(Not run)