Statistics[LinearFilter] - apply linear filter to a data set
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Calling Sequence
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LinearFilter(X, Y, options)
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Parameters
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X
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data set
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Y
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filter
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options
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(optional) equation(s) of the form option=value where option is one of ignore or initial; specify options for the LinearFilter function
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Description
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The LinearFilter function applies linear filter to a set of observations. By default, convolution method is used:
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`X'`[i] = Sum(X[i+1-j]*Y[j], j = 1..m);
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where m is the size of the filter. For the set of initial values will be used. By default, X is padded on the left with zeros. Option initial can be used to specify the initial values.
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Recursive filter is defined as follows:
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`X'`[i] = X[i]*Y[1]+Sum(`X'`[i+1-j]*Y[j], j = 2..m);
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The first parameter X is a single data sample - given as a Vector or list. Each value represents an individual observation.
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The second parameter Y is the filter - given as a Vector or list. Each value represents a filter coefficient.
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Options
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The options argument can contain one or more of the options shown below.
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ignore=truefalse -- This option is used to specify how to handle non-numeric data. If ignore is set to true all non-numeric items in data will be ignored. Missing values are allowed in the data set but not in the filter.
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initial=deduce, or Vector -- This option specifies the initial values in reverse order. The default is a set of zeros.
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recursive=truefalse -- If this option is set to true then recursive filter will be used.
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Examples
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