An Echoview "variable" is a time-series of measurements of one data type. Echoview uses variables to organize source data (e.g. data files from an echosounder) for display, analysis, export, etc. purposes.
Variables are represented on the Variables and Geometry window and in the Raw variables section of the Filesets window.
Example:
A data file from an echosounder may contain the transmitted and received properties of acoustic pulses (pings), and the geographic position of a ship at the time each ping was transmitted. Echoview would derive one or more acoustic variables from this data file (an Sv variable, TS variable, a single target variable, etc.) and a position variable e.g. (the GPS fix for each ping). The acoustic variables can then be displayed as echograms, analyzed, exported etc. The position variable can be displayed as a cruise track.
Variables are divided into two main categories.
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Variable category |
Description |
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Variables that are derived directly from data stored in data files. |
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Variables that are created from other variables using operators (mathematical algorithms). |
Each variable in Echoview has:
Raw variables are automatically named by Echoview. For naming conventions see:
Raw variables derived from ASCII data files
Raw variables derived from BioSonics data files
Raw variables derived from DIDSON data files
Raw variables derived from EchoListener data files
Raw variables derived from Furuno data files
Raw variables derived from HAC data files
Raw variables derived from HTI data files
Raw variables derived from Kaijo data files
Raw variables derived from Kongsberg data files
Raw variables derived from Precision acoustics data files
Raw variables derived from RD Instruments Workhorse data files
Raw variables derived from Reson data files
Raw variables derived from Simrad data filesVirtual variables can be named when they are created, and renamed at any time later on the Notes page of the Variable Properties dialog box.
Defined on the Notes page of the Variable Properties dialog box.
Variables are divided into the following classes.
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Variable class |
Description |
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Variables that contain a time-series of measurements associated with the transmitted and received properties of ping.
Note: The data type of an acoustic variable may not be same as the data type stored in a data file, e.g. a data file may contain voltage measurement from which Echoview derives Sv values to create an Sv variable. |
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Variables that contain a time series of measurements associated with the heading, roll, pitch, yaw and heave of a platform.
Note: Only heading, roll, and pitch variables are currently supported. |
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Variables that contain a time-series of measurements associated with geographic location of a platform.
Note: Only GPS fixes are currently supported |
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Variables that contain a time-series of measurements associated with distance travelled by a platform from an arbitrary zero point.
Note: Only vessel log variables are currently supported. |
About raw variables
About virtual variables
About the Variables and Geometry window
Data types