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Tolerance:
The requirements for a value filter can be relaxed by entering a tolerance. An example best
describes this process:
Suppose the value filter is currently using two fields: Diameter (ESD) and Aspect Ratio.
Field
Min
Max
ESD
10.0
20.0
Aspect Ratio
0.8
1.0
Setting the tolerance value to 50% would result in new constraints for the filter to be calculated when it
is applied. This tolerance valule would be calculated in the manner below resulting in new Min and
Max values for ESD and Aspect Ratio (as displayed on the second table).
ESD tolerance = (20.0 - 10.0) x 0.5 = 5
Aspect Ratio tolerance = (1.0 - 0.8) x 0.5 = 0.1
Field
Min
Max
ESD
5.0
25.0
Aspect Ratio
0.7
1.1
Statistical Filter Behavior
Use Statistical Filter:
Unlike a Value filter, a Statistical filter cannot be manually created. The
software will automatically check this box if an underlying Statistical filter definition exists. A user can
disable a Statistical filter by using this checkbox. An example situation where the user would want to
use this checkbox is when a Value filter was also defined.
Auto-Select Particles:
Normally a Statistical filter will use the highest scoring particle part of the
training set as the cutoff score for selecting particles that match. Unchecking this box will disable this
behavior. If a Value filter using the Filter Score field is manually defined, that will take precedence.
General Filter Behavior
Apply Value Filter First:
If both a Value and Statistical filter are defined, the order in which they are
applied can be modified by this checkbox.
Invert Filter Result:
The result of any filter can be inverted using this checkbox
Like Selected Particles (Value)… (F4)
This option uses the currently selected particles as a training set and builds a Value filter. The
constraints for each data field (in the filter) are derived from the minimum and maximum values for the
field among all of the training set particles. The resulting value filter is then applied against the entire
dataset and the selection results are displayed. At a minimum, the training set particles will be selected,
but other particles that fall within the constraints are also selected. The Value filter that was built can be
manually modified by opening the Filter Dialog under the Filter menu. Typical modifications would be
