Extraction Types

By default the function will perform the same operation on all numeric fields in the file (except from/to fields). However, in some cases you need to use the Use other extraction type option to control the type of calculation on a field-by-field basis.

For example, you may require average North and East values and the lowest Z. Special handling of any numeric field may be selected from the following option in the Define Extraction Types dialog box.

Numeric Field

Double-click (or click on the Select icon) to select the name of the fields to which you want to apply a special extraction.

Extraction Type

For each field you specify, select an extraction type from the drop-down list.

The Extraction type you selected in the main form will be used for all fields not entered in this form. The following options are provided:

AVERAGE 

Calculates the arithmetic average.

WTAVG 

Calculates the length weighted average.

MIN 

Extracts the minimum field value.

MAX 

Extracts the maximum field value.

SUM 

Totals the field values.

FIRST 

Extracts the first field value.

LAST 

Extracts the last field value.

BLANK 

Leaves the field blank.

IGNORE 

Excludes the field data from the Output file.