About analysis variables

The result of any exported analysis is one or more files containing comma separated values (.csv format) and a header line which identifies what each column contains. The header line contains the names of the analysis export variables which are in the file.

Some analysis variables are exported automatically, others must be selected on the Export page of the EV File Properties dialog box in order to be exported.

The order of the columns (variables) in an exported file is held constant across Echoview releases to ensure that any software you have or create in order to process such exported data can use the column number reliably to interpret the data, for a given type and configuration of export.

The analysis variables are grouped into the following categories:

General analysis variables

Variables listed with + must be selected on the Export page of the EV File Properties dialog box in order to be exported.

Some variables are not listed on the Export page of the EV File Properties dialog box, they are exported automatically with the appropriate type of analysis export.

In the following list of analysis variables the order is alphabetic (not the order in which the columns appear in the exported file). Groups of very closely related variables are summarized, not listed individually, in order to improve legibility (e.g. Date_E, M & S, is short for Date_E and Date_M and Date_S).

Analysis common Analysis domain Analysis export
Date_E+, M & S Bad_data_no_data_samples EV_filename+
Dist_E+, M & S Bad_data_empty_water_samples Processing_date+
Frequency+ Beam_volume_sum Processing_time+
Lat_E+, M & S Depth_mean Processing_version+
Lon_E+, M & S Exclude_above_line_depth_mean Program_version+
Num_intervals+ Exclude_above_line_range_mean  
Num_layers+ Exclude_below_line_depth_max  
Ping_E+, M & S Exclude_below_line_depth_mean  
Region detection settings+ Exclude_below_line_depth_min  
Region_notes+ Exclude_below_line_range_max  
Time_E+, M & S Exclude_below_line_range_mean  
VL_end+mid & start Exclude_below_line_range_min  
Dist_E_from_transect_S+M & S First_layer_depth_start  
Duration_E_from_transect_S+M & S First_layer_range_start  
Ping_E_from_transect_S+M & S Grid_reference_line
Transect_interval Good_samples*
VL_end_from_transect_S+mid & start Heave_max  
  Heave_mean  
  Heave_min  
  Heave_source  
  Height_mean  
  Last_layer_depth_stop  
  Last_layer_range_stop  
  Layer_depth_max  
  Layer_depth_min  
  Layer_bottom_to_reference_line_depth  
  Layer_bottom_to_reference_line_range  
  Layer_range_max  
  Layer_range_min  
  Layer_top_to_reference_line_depth  
  Layer_top_to_reference_line_range  
  No_data_samples  
  Range_mean  
  Region_bottom_altitude_max  
  Region_bottom_altitude_mean  
  Region_bottom_altitude_min  
  Region_top_altitude_max  
  Region_top_altitude_mean  
  Region_top_altitude_min  
  Samples Above Surface Exclusion  
  Samples Below Bottom Exclusion  
  Samples In Domain  
  Thickness_mean  
  Wedge_volume_sampled  

*Prior to Echoview 5.2 Good_samples was known as Samples.

Integration analysis variables

Variables listed with + must be selected on the Export page of the EV File Properties dialog box in order to be exported.

Some variables are not listed on the Export page of the EV File Properties dialog box, they are exported automatically with the appropriate type of analysis export.

Variables listed with ++ will only be exported if you have the School Detection module licensed. School/Region altitude analysis variables can be found under the Analysis domain group (above).

In the following list of analysis variables the order is alphabetic (not the order in which the columns appear in the exported file).

Integration results Integration schools Integration settings Biomass
ABC 3D_school_volume++ Alpha Density_number
ABC_noise Attack_angle++ Bottom_offset+ Density_weight
Aggregation_index Coefficient_of_variation++ Exclude_above_line_applied  
Area_Backscattering_Strength Corrected_area++ Exclude_below_line_applied  
Center_of_mass Corrected_length++ Gain_constant  
Equivalent_area Corrected_mean_amplitude++ Maximum_integration_threshold  
Inertia Corrected_mvbs++ Maximum_Sv_threshold_applied  
Kurtosis Corrected_perimeter++ Minimum_integration_threshold  
NASC Corrected_thickness++ Minimum_Sv_threshold_applied  
NASC_noise Horizontal_roughness_coefficient++ Noise_Sv_1m  
PRC_ABC Image_compactness++    
PRC_NASC Uncorrected_area    
Proportion_occupied Uncorrected_length    
Skewness Uncorrected_perimeter    
Standard_deviation Uncorrected_thickness    
Sv_max Vertical_roughness_coefficient++    
Sv_mean      
Sv_min      
Sv_noise      
Bottom_roughness_normalized #      
Bottom_hardness_normalized #      
First_bottom_length_normalized #      
Second_bottom_length_normalized #      

Notes

#A selectable bottom point analysis value output to an integration analysis .csv file. This and other bottom point values may also be selected to be displayed with onscreen integration results. A complete bottom point variable export is available through using Export data with a cruise track, table or dataflow bottom points variable.

A fixed platform affects integration schools variables and other associated analysis variables.

Bottom points variables

Variables listed with +++ cannot be selected on the Export page of the EV File Properties dialog box, they are exported automatically with the appropriate type of analysis export.

See Export file formats for more information on the groupings of variables that are exported for Database or Spreadsheet output

Bottom
Point_index +++
Point_date+++
Point_time+++
Point_milliseconds+++
Latitude+++
Longitude+++
Altitude+++
Altitude_of_water_surface+++
Depth+++
Class_ID+++
Class_name+++
Bottom_roughness_normalized*
Bottom_hardness_normalized*
First_bottom_length_normalized*
Second_bottom_length_normalized*
Bottom_rise_time_normalized*
Bottom_line_depth_mean*
Bottom_max_sv*
Bottom_kurtosis*
Bottom_skewness*

*The bottom feature is included in an integration export only when the feature is chosen for feature extraction for the bottom points variable.

Single target and fish track analysis variables

Variables listed with + must be selected on the Export page of the EV File Properties dialog box in order to be exported.

Some variables are not listed on the Export page of the EV File Properties dialog box, they are exported automatically with the appropriate type of analysis export.

Variables listed with ++ can only be exported if you have the Fish Tracking module licensed.

In the following list of analysis variables the order is alphabetic (not the order in which the columns appear in the exported file). Groups of very closely related variables are summarized, not listed individually, in order to improve legibility (e.g. Angle_minor_axis & major is short for Angle_minor_axis and Angle_major_axis). See Export file formats for more information on the groupings of variables that are exported for Database or Spreadsheet output

Single targets Fish tracks Frequency distribution
Num_targets Direction_horizontal++ Bin_count
Target_depth_min, mean & max1 Direction_vertical++ Bin_TS_mean
Target_range_min, mean & max Distance_2D_unsmoothed++  
Target_length_mean+ Distance_3D_unsmoothed++  
TS_max Fish_track_change_in_depth++1 & range++  
TS_mean Speed_2D_max_unsmoothed++ & mean++  
TS_min Speed_4D_max_unsmoothed++ & mean++  
  Time_in_beam++  
  Tortuosity_2D++  
  Tortuosity_3D++  

1Echoview 6 renamed Target_depth to Target_on_axis_depth. With this change, the calculations for Target_depth_mean, Target_depth_max, Target_depth_min and Fish_track_change_in_depth changed to assess Target_true_depth values.

Automatically exported variables

Under new EV files, these analysis variables are automatically exported or selected by default.

Variable name Export type or comments
Process_ID
Layer
Interval

Export integration.

Calculation identifier and cell data.

Region_class
Region_ID
Region_name
Region_bottom_altitude_min
Region_bottom_altitude_max
Region_bottom_altitude_mean
Region_top_altitude_min
Region_top_altitude_max
Region_top_altitude_mean

Export 3D region integration.

3D object.

By Regions export for all variants under spreadsheet or database mode except for Wideband Frequency Response.

 

Depth mean

When Uncorrected length or Corrected length are selected on the Export page of the EV File Properties dialog box.

C_bad_data no data_samples
C_bad_data_empty_water_samples
C_no_data_samples
C_good samples*

Export integration analyses by cells or by regions by cells if Output empty cells is selected on the Export page of the EV File Properties dialog box.

*Prior to Echoview 5.2 C_good_samples was known as C_samples.

Species_ID
Species_name
Species_percent
Species_name

Export integration by regions.

When Density weight or Density number are selected on the Export page of the EV File Properties dialog box.

Attribute
Targets_binned
Targets_excluded
Targets_failed_filter
Targets_failed_thresholds
Targets_missed_bins
Distance_minor_axis2
Distance_major_axis2
Grid_reference_line3
Target_on_axis_depth2
Region_detection_settings1
Region_notes1

Export Frequency distribution.

Variations of By Regions, Frequency Distribution spreadsheet or database files also include selected region analysis variables.

 

1 Included with Analysis By Regions, Frequency Distribution, Database, regions file.

1 Included with Analysis By Regions By Cells, Frequency Distribution, Database, cells file.

 

2 Included with Analysis By Regions, Frequency Distribution, Database, targets file.

 

3 Included with Analysis By Cells or Analysis By Regions By Cells, Frequency Distribution, Spreadsheet file.

Angle_minor_axis# & major#
Distance_minor_axis3 & major3
Exclude below line depth*
Fish_track_change_in_depth5
Height mean2
Ping_date, time & millisecond
Ping_number
Pulse_duration4
Pulse_start_normalized_PLDL4, 6dB4, 12dB4 & 18dB4
PulseLength_normalized_PLDL4, 6dB4, 12dB4 & 18dB4
PulseLengthDeterminationLevel4
Samples_above_PLDL4
StandDev_angles_minor_axis4 & major4
Target_on_axis_depth1, 2a, 2b, 3, 4
Target_range
Target_true_depth
TS_comp & uncomp
Target_latitude
Target_longitude
Target_northing
Target_easting
Target_length
Target_length_uncompensated
Target_length_manual
Target_perimeter
Target perimeter edge midpoints
Target_area
Target area edge midpoints
Target_intensity_variation
Target_compactness
Target compactness edge midpoints
Target_thickness
Target_length across beams
Target_range extent
Target class
Target orientation
Thickness mean2


Export Single targets.

Export By Regions variations for Single targets and Fish tracks also include selected region analysis variables.

 

# This analysis variable is available only when Database format is selected on the Export page of the EV File Properties dialog box.

 

* This analysis variable is not available in analysis exports, but in data exports only.

 

1 Echoview 6 renamed Target_depth to Target_on_axis_depth. With this change, the calculations for Target_depth_mean, Target_depth_max, Target_depth_min and Fish_track_change_in_depth changed to assess Target_true_depth values.

 

2 Included in Analysis By Regions By Cells, Integration file or Export Fish tracks file.

2a Included in Analysis By Cells, Fish tracks, Database, targets file.

2b Included in Analysis By Regions, Fish tracks, Database, targets file.

 

3 Included in Analysis By Regions, Single targets, Database, targets file.

3 Included in Analysis By Regions By Cells, Single targets, Database, targets file.

 

4 Included in Analysis By Regions or Analysis By Cells, Fish tracks, Database, targets file.

4a Included in Analysis By Regions, Fish tracks, Database, targets file.

 

5 Included in Analysis By Cells, Fish Tracks, Database, cells file.

Transect_ID
Transect_name

These variables are automatically exported if there is an assigned transect group.

See also

Multibeam analysis variables
About analysis
About exporting analyses
Export variable lists
Special export values