SMS:Smooth Dataset

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File:Smooth Data Sets.jpg
Smooth Data Sets Dialog

The Smooth Data Set dialog is used to condition scattered data scalar values before those values are used in an interpolation process. This includes two general applications, smoothing a size data set to prevent the data set values from changing too quickly, and smoothing depth/elevation values to prevent extreme slopes.

The Smooth Data Set dialog is accessed via the Data Set Toolbox by selecting Data | Data Set Toolbox in the Scatter module.

Smoothing Size Data Sets

One measure of mesh quality is element area change. If the data set values change too quickly in a size data set, the element area change of adjacent elements may be too great, resulting in poor mesh quality.

Smoothing options

  • Element area change limit - The selected data set values will be modified to honor the specified element area change limit.
    • Minimum value anchor type - Data set values are decreased. Results in a more refined (more nodes/elements) mesh when used as a size data set.
    • Maximum value anchor type - Data set values are increased. Results in a less refined (fewer nodes/elements) mesh when used as a size data set.
  • Minimum node spacing - The minimum value allowed in the smoothed data set.

Tips

  • After smoothing a size data set, use the data calculator to subtract the smoothed sized data set from the original data set and create a "change" data set. Contour the "change" data set to easily determine what and where changes were made by the smoothing algorithm.

Smoothing Elevation/Depth Data Sets

This option allows the user to specify a maximum slope. The process creates a new data set which honors the maximum specified slope.

  • Minimum value anchor type - The smoothing operation anchors the minimum data set value (such as the lowest elevation or smallest depth) and adjusts the adjacent values to ensure the slope is less than or equal to the specified slope.
  • Maximum value anchor type - The smoothing operation anchors the maximum data set value (such as the highest elevation or largest depth) and adjusts the adjacent values to ensure the slope is less than or equal to the specified slope.

The operation includes all scatter points if none are selected. Alternatively, the user may select a group of scatter points to be operated on. Points not selected will not have their scalar value modified. This means the only way to modify a point is if it has an adjacent point that is also selected and the slope between these two selected vertices is steeper than the maximum specified slope.

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