Ping Subset

This operator allows you to create a variable containing a subset of the pings in another variable.

You enter the processing settings for this operator on the Ping subset page of the Variable Properties dialog box. The Ping range or Ping ranges can be specified by number, time or distance traveled.

See also: The Effect of No data samples on the Wideband Frequency Response graph page.

Echoview accepts operands of the following data types as input:

Operand 1

Angular position
Boolean
Color
Complex angular position
Complex power dB
Complex Sv
Complex TS
Current velocity
Linear
Multibeam angular position
Multibeam boolean
Multibeam color
Multibeam magnitude
Multibeam phase
Multibeam Sv
Multibeam targets
Multibeam TS
Multibeam unspecified dB
Power dB
Pulse compressed complex angular position
Pulse compressed complex power dB
Pulse compressed complex Sv
Pulse compressed complex TS
Single targets
Sv
Target length
TS
Unspecified dB

Settings

The Ping Subset Variable Properties dialog box pages include (common) Variable Properties pages and these operator pages:

Operands page

Ping Subset page

Settings

Description

Ranges

Select whether the ping ranges will be specified by ping number, time or distance (in meters or nautical miles), then specify the operand ping ranges to be used. Ranges are separated by commas. Invalid ping ranges prompt a warning message.

Number

Specify pings by their numbers in order. Single numbers or ranges may be used. An unterminated range spans to the last ping.

e.g. 5,7, 9-20, 25-

Time (valid Ranges from 1970 to 2050)

Specify pings by one or more time ranges in abbreviated ISO 8601 format. Note that the `=` sign is used to indicate a continuing range between the specified start and end times.

e.g. 2012-6-28 12:30=13:45, 16:00=

You can write times in full, or you use these abbreviation rules:

Rule	Specification	Abbreviation	Description
Omit leading zeros	1970-01-02 03:04:05.06	1970-1-2 3:4:5.06	Leading zeros may be omitted, except in the subsecond.
Omit trailing zeros	1970-1-1 0:0:0.000	1970	An incomplete time is filled in with the minimums (1 for month or day, and 0 for time).
Omit leading duplicate fields	2012-1-20 = 2012-1-22	2012-1-20 = --22	Omitted year, month and day fields (abbreviated as --) take their value from the most recent specified date.
Omit unused date separators	2012-1-20 11:15 = -- :45	2012-1-20 11:15 = :45	If the date is omitted then the dashes are not needed.

Distance (m)

Distance specification is entered as a start distance, a dash and a stop distance.

e.g. 0-9.5

Distance (nmi)

Distance specification is entered as start distance, a dash and a stop distance.

e.g. 2.58-4.00

Include the ping ranges

Exclude the ping ranges

Select whether the specified ranges are included or excluded.

Pings

The Pings section lists the actual pings included or excluded, next to the corresponding ranges.