Add Set Window

Sets can be created in Dips with the Add Set Window option.

Add Set Window allows you to draw windows around data clusters on the stereonet, for the purpose of obtaining mean orientations of data (poles) within the windows. The mean orientations can be plotted as poles and/or planes on the stereonet, and set statistics (confidence and variability cones) can be plotted (Edit Sets option) or listed (Info Viewer option).

• The Set Windows created with the Add Set Window option are curvilinear four-sided windows, defined by two trend values and two plunge values at opposite corners.

• Circular set windows can also be created with the Add Set Window (Circular) option, to facilitate the selection of data near the center of the stereonet.

The following instructions describe the basic procedure of adding a Set Window. Further important information is found in the following topics:

Multiple Windows for a Single Set

Wrapped Set Windows

Overlapping Set Windows

Adding a Circular Set Window

To add a curvilinear four-sided Set window:

1. Select Add Set Window from the toolbar or the Sets menu.

2. In the active view (a Contour Plot is recommended), locate the cursor on one of the two COUNTER-CLOCKWISE corners of the data set to be captured. The initial position of the cursor is important, since the window is formed in a CLOCKWISE direction. Remember that the cursor coordinates are always displayed in the Status Bar.

3. Click the LEFT mouse button to enter the first corner. Now move the cursor CLOCKWISE and you will see a window stretching from the selected corner to the current cursor position.

4. NOTE – if the cursor moves beyond the stereonet perimeter, it will "wrap around" and re-appear on the opposite side of the stereonet, with the window still attached. This allows data near the perimeter, on opposite sides of the stereonet, to be selected as one Set. See the Wrapped Set Windows topic for more information.

5. Once you have stretched the window to enclose all of the desired data, click the LEFT mouse button again to enter the second window corner.

6. The Add Set Window dialog will appear, allowing you to enter the Set ID, modify the graphically entered window limits (if necessary), and also provide labeling and visibility information (see below for details).

7. Select OK, and the Set will be created and added to the document. The Set Window will be displayed on the plot, and all poles within the window will be used to calculate the mean orientation of the Set. The mean planes / poles will be displayed according to the visibility settings chosen.

8. NOTE – A SET COLUMN IS AUTOMATICALLY ADDED TO THE SPREADSHEET WHEN THE FIRST SET IS CREATED. The Set Column records the Set ID of data belonging to Sets. Each time a Set Window is added, the Set Column is updated accordingly.

Add Set Window dialog

The following options are available in the Add Set Window dialog.

Set ID

• A default Set ID will always appear, which is ONE GREATER than the highest existing Set ID used in the current document. You DO NOT have to use this number, it is simply provided as a convenience.

• To create a new set, enter a new Set ID.

• Since Dips allows multiple WINDOWS to be used to define a single SET, you may enter an EXISTING Set ID for a new window. In this case, the existing Set will be modified to include the new data.

• Note that a list of the existing Set IDs appears as a drop-down list in the Set ID area. This is a convenience if you wish to see the current ID numbers in use.

• The Set ID must be an integer greater than zero.

Label

The Set Label is an optional descriptive label for the Set. By default it is NOT displayed when Sets are created. It can only be displayed through the Edit Sets dialog, after creating a Set.

Window Limits

The graphically entered window limits ("First Corner" and "Second Corner") can be modified if necessary, in the Add Set Windows dialog.

NOTE: the orientation format of the window limits will depend on the current Convention in effect.

• If the Convention is Pole Vector, then the window limits will appear in Trend / Plunge format.

• If the Convention is Plane Vector, then the window limits will appear in the format corresponding to the Global Orientation Format (e.g. Dip / DipDirection or Strike / Dip).

Visibility

With the Visibility checkboxes, you can display:

• Mean Pole Vector(s) only

• Mean Plane(s) only

• Mean Pole Vector(s) and Mean Plane(s)

You can also choose to plot UNWEIGHTED and / or WEIGHTED poles / planes. See the Terzaghi Weighting topic for information on the Terzaghi / Traverses bias correction (weighting) used in Dips.

For visible MEAN poles / planes displayed on the stereonet:

• The letter "m" beside the Set ID indicates the UNWEIGHTED mean pole/plane.

• The letter "w" beside the Set ID indicates the WEIGHTED mean pole/plane.

• By default, the Set ID is always shown when a Set is created. The optional Label (see above) is NOT shown.

The visibility settings that you choose in the Add Set Window dialog can be modified AT ANY LATER TIME in the Edit Sets dialog.