Output empty cells

The Output empty cells option on the Export page of the EV File Properties dialog box is used to select whether data from empty cells should be included in the following exports:

• Integration by cells
• Integration by regions by cells
• Single target analysis by cells
• Single target analysis by regions by cells
• Fish Track analysis by cells
• ICES CSV export

If you select this option, data that describes the cell (e.g. cell layer number and interval number, minimum and maximum layer depth, number of the first and last ping in the cell) will be exported. Data that describes the contents of the cell will be exported as zero or a special export value.

Empty cell definition

The definition of an empty cells differs by export type.

• Integration
• ICES CSV exports
• Single target exports
• Fish track exports

For Integration exports

A cell is defined as an empty cell when Good_samples = 0 and Bad data empty water samples = 0

Notes:

• Empty cells that are excluded by lines or bad data regions will not be analyzed.
• Empty cells that have not been excluded by lines or bad data regions will be analyzed.
• Empty cells appear at the bottom of export file after the output for all non-empty cells.

For Single target exports

A cell is defined as an empty cell when Good_samples = 0 and Bad data empty water samples = 0 and it does not contain any targets.

Notes:

• This is only applicable to Echogram menu: Export > Analysis by cells > Single Targets... Users who use Frequency distribution graph analysis are advised to read information about Frequency distribution graphs and Exporting single target frequency distributions.
• If you are exporting using the database format, the empty cell information will be added to the cells file but will not be added to the targets file.

For Fish track exports

A cell is defined as an empty cell when Good_samples = 0 and Bad data empty water samples = 0 and it does not contain any fish track end points.

Notes:

• Empty cells appear at the bottom of export file after the output for all non-empty cells.
• If you are exporting using the database format, the empty cell information will be added to the cells file but will not be added to the targets file.
• The Num_targets analysis variable displays different data for empty cells and non-empty cells:
  • For non-empty cells it displays the number of single targets in the fish track region. See also About fish track regions - Inclusion in cells.
  • For empty cells it displays the number of single targets in the empty cell.

For ICES CSV exports

ICES CSV export empty cell Data Record rows appear after the output of non-empty cell Data Record rows.

The special value 9999 or -9999 is output when an analysis cell:

• is outside of an exclusion line
• is contained within a Bad data region

Under the Analysis by Region Classes by Cells export, the value 0 is output when the cell is outside of a specified region and the cell does not have a value of 9999 or -9999.

Notes:

• Only visible region classes and analysis regions are handled by the ICES CSV export.
• Empty cells are exported for cells within a transect when the ICES analysis region class intersects with a transect in an assigned transect group.

See also 

About exporting analyses