|
|
The Outlier Filter passes only values that are within a band you specify. Specify
the band with the attributes Band Center and Band Range. If Outlier Replacement
is
yes, the filter replaces out-of-range values with the nearest in-range value. If
Outlier Replacement is no, the filter discards out-of-range values.
floating, each time the block
passes a value, that value becomes the center of the range. If Band Type is fixed,
the range always remains the same.
Specifying a Range
The attribute Band Range specifies the size of the block's range. Set it to the difference between the highest and lowest values in the range. The filter's range
contains the values between the range's center minus Band Range/2 and the
range's center plus Band Range/2.
fixed, you set the attribute Band Center and NOL uses the value of Band Center as
the center of the range.
floating, NOL uses the last value it passed as the center, and NOL
ignores the value of the attribute Band Center. Because the block always passes in-
range values, the center is always set to an in-range input value.
yes,
it changes the center of the range to the in-range value nearest to the input value.
If Outlier Replacement is no, the center does not change.
Note: If Band Range is none, NOL uses a Band Range of 0.0. If Band Center is
none, NOL proceeds as if Band Type were floating.
Specifying How to Round Output Values
To round the output values, set the field Quantization. The block rounds its
output value to the unit you specify. For example, if Quantization is 0.1, the block
rounds to the nearest tenth, and if Quantization is 1.0, the block rounds to the
nearest integer.
| If Quantization is... | The filter passes these values | ||
|---|---|---|---|
none
|
0.5
|
1.43
|
1.77
|
0.1
|
0.5
|
1.4
|
1.8
|
0.5
|
0.5
|
1.5
|
2.0
|
1.0
|
1.0
|
1.0
|
2.0
|
This field is especially useful when you need to keep output values within known
accuracy limits.
Configuring
This is the configuration panel for the Outlier Filter.
|
Examples
This section has some examples of a fixed and floating Outlier Filter.
Fixed Band
This figure shows some input values for an Outlier Filter with Band Type set to
fixed. The Band Range and Band Center are marked. Letters mark values that are
passed without replacement. If Outlier Replacement is yes, the filter replaces
unmarked values with the nearest in-range value. Otherwise, the filter does not
pass any value.
|
Floating Band
The next two figures show some input values for an Outlier Filter with Band Type
set to floating. They differ in how Outlier Replacement is set. In both, the range is
marked with a bold line, and the center of the range is marked with a thin line.
no. Notice that the center of the range
changes only when a new input value falls in the same range as the previous
value. Letters mark values that the block passes.
|
In this figure, Outlier Replacement is
yes. Notice that when a value is out of
range, the center of the new range becomes the maximum or minimum of the old
range. Letters mark values that the block passes without replacing. For unmarked
values, the filter passes the closest in-range value.
|
See Also
For more information on how to use this block, see the sections below.
| Click here for more information... |
|---|
|
Basic Block Behavior
|
|
Data Pair Outlier Filter
|
|
Novelty Filter
|
| Prev
| Next | Start of Chapter | End of Chapter | Contents | Index | (12 out of 25)
Copyright © 1996, Gensym Corporation, Inc.