Filtering and despiking settings gui

Overview

The Filtering and Despiking Settings GUI allows you to select options relevant to the use of applying filtering and despiking to your data. See the windowfilter wiki page for more information on the underlying function.

Algorithm

The algrothim governs what filtering algorithm is used. The algorithms to select from are:

• Mean
• Median
• Min
• Max
• Despike
• Mean Trimmed
• Median Trimmed

Window Filter

The window filter value must be an odd integer and corresponds to the window width of the filter.

Mode/Dimension

Mode/Dimensions to filter ACROSS. Selecting Mode 2/Columns will filter ACROSS the rows. Selecting Mode 1/Rows will filter ACROSS the columns. The default is to filter across the rows.

Despike Parameters

When the algorithm is "Despike", these parameters will appear in the settings GUI.

Tolerance:

• If tolerance is empty then despike uses the std(median(x)) within each window to define the tolerance within the window.
• If tolerance is a scalar and is $>0$, then tolerance defines the tolerance for all the windows.
• If tolerance is a scalar and is $<=0$, then tolerance is estimated by the mean absolute deviation of madc(x.data(:)) and is the tolerance used for all the windows (see MADC).

Tolerance must be a scalar or empty. The default is 2. To set the Tolerance to empty, use empty brackets ([]).

Threshold:

• In contrast to replacing all values with the median (e.g., for when algorithm is set to "median"), 'despike' replaces only values outside $|x-median(x)|>threshold*tolerance$ with the median.

Top or Bottom Flag:

• For Top or Bottom flag = 'middle' the filter replaces values outside $|x-median(x)|>threshold*tolerance)$ with the median.
• For Top or Bottom Flag = 'bottom' the filter replaces values outside $(x-median(x))>threshold*tolerance$ with the median.
• For Top or Bottom Flag = 'top' the filter replaces values outside $(median(x)-x)>threshold*tolerance$ with the median.

Trimming Parameters

When the algorithm is "Mean Trimmed" or "Median Trimmed", this parameter will appear in the settings GUI.

Trimming Factor:

If trimming factor is:

• $>1$ and even, then it is the number of samples to exclude from the calculation.
• $0<n<1$, is the fraction of samples to exclude from the calculation.
• $>m$(dim), then it is set to zero and the normal mean/median is used.

See also:

windowfilter, meantrimmed, mediantrimmed