Perform Self (Cluster) Match

Use the Perform Self (Cluster) Match option (Geosoft.uxo.gxnet.dll(Geosoft.GX.UXO.UxaPerformSelfMatch;Run)*) from the AGC Expert User > Source and Library Management menu to classify the targets against a master signature library.

Perform Self Match dialog options

Source Database
Name	Specify the source database. Script Parameter:UXAPERFORMSELFMATCH.TARGET_DATABASE_NAME
Group	Select the source group. Script Parameter:UXAPERFORMSELFMATCH.TARGET_DATABASE_GROUP
ID channel	Select the source ID channel. Script Parameter:UXAPERFORMSELFMATCH.TARGET_DATABASE_ID
Mask channel	Select the source mask channel. Script Parameter:UXAPERFORMSELFMATCH.TARGET_DATABASE_MASK
Mask channel - all solutions	Select the source mask channel for all solutions. Script Parameter:UXAPERFORMSELFMATCH.TARGET_DATABASE_MASK
Match channel suffix	Select/specify the channel suffix. Channel suffix will be added to "UXA_LmStat_" and "UXA_LmID_" prefixes to create match statistics and match ID channel names. Script Parameter:UXAPERFORMSELFMATCH.CHANNEL_SUFFIX
Match statistics channel	Read only field - contains match statistics channel name. Match statistics metric shows the degree of match between a target and the items in the signature library, so its size would be the same as the number of items in the signature library. Script Parameter:UXAPERFORMSELFMATCH.MATCH_STATISTICS
Match ID channel	Read only field - contains match ID channel name. Each item in this channel shows the indices of the items in the signature library associated with the match ID values. Script Parameter:UXAPERFORMSELFMATCH.MATCH_ID
Cluster threshold	Specify the match threshold. Default value is 0.95. Script Parameter:UXAPERFORMSELFMATCH.TARGET_DATABASE_ID
Above threshold channel	Specify the above threshold channel, which displays the number of matches above the threshold. Script Parameter:UXAPERFORMSELFMATCH.TARGET_DATABASE_ID
Match Calculation Options
Min. polarizability amplitude	Specify the minimum polarizability amplitude, which is the lower bound of the polarizability values used in the classification. This value should be above or equal to zero. The default value is zero. Script Parameter:UXAPERFORMSELFMATCH.MIN_BETA_AMP
Gates - Low	Select the low gate, which will affect the match statistic. Script Parameter:UXAPERFORMSELFMATCH.LOGATE
Gates - High	Select the high gate, which will affect the match statistic. Script Parameter:UXAPERFORMSELFMATCH.HIGATE
Criteria weights - Size	Specify the size. See the Application Notes below for more information. Script Parameter:UXAPERFORMSELFMATCH.WEIGHT_SIZE
Criteria weights - Shape 1	Specify the shape. See the Application Notes below for more information. Script Parameter:UXAPERFORMSELFMATCH.WEIGHT_SHAPE1
Criteria weights - Shape 2	Specify the shape. See the Application Notes below for more information. Script Parameter:UXAPERFORMSELFMATCH.WEIGHT_SHAPE2

Application Notes

The self-match routine reads in a group containing polarizability data for sources and compares them to each other.

For each source in the group from the source database, the matching routine compares it to all the other sources and generates a match statistic. The match statistic for each of the three polarizabilities are combined in to a final single match statistic or metric based on the weighting using the following criteria:

Size - the primary polarizability (β1),
Shape 1 - the secondary polarizability normalized by primary polarizability (β2/β1), and
Shape 2 - the tertiary or third polarizability normalized by primary polarizability (β3/β1).

By appropriately selecting the criteria weights, the match can based on 1, 2 or 3 of the polarizabilities. The match statistic ranges between 0 and 1, where 1 is a perfect match. This statistic and the matched source id description are each stored as array channels in the source database, labelled with the Match Channel Suffix.

The match criteria is computed at all time gates, expect where the values of a polarizability are below the minimum amplitude. If the polarizabilities used do not exceed the defined minimum amplitude, and the comparison cannot be performed, a metric of exactly zero (0) is returned.

Two or more sources with a match statistic greater than the cluster threshold are said to form a "cluster". The number of other or additional sources in the cluster is stored in the Above Threshold channel.

To help you visualize clusters of similar sources that are found above a specified self-match threshold, see the Highlight Self-match Cluster topic.

*The GX tool will search in the "gx" folder. The GX.Net tools, however, are embedded in the Geosoft.uxo.gxnet.dll located in the bin folder. If running this GX interactively, bypassing the menu, first change the folder to point to the bin folder, then supply the GX.Net tool in the specified format.