The Measure Angle
option allows you to calculate the angle between any
two points (planes) on the stereonet.
To use Measure Angle:
Select Measure Angle
from
the Tools menu.
Click the left mouse button at a point (pole) on the stereonet. Remember that the cursor coordinates are always displayed in the Status Bar.
Click the left mouse button at a second point (pole).
A dialog will immediately appear, displaying the acute and obtuse angles between the two points (poles) selected.
In the Measure Angle dialog, the coordinates of the two selected points are also displayed, in the format corresponding to the current Convention (i.e. Trend / Plunge or Plane Vector format). If these graphically entered coordinates are not the exact coordinates intended, then simply enter the correct coordinates, and the angle between the new points will immediately be displayed.
The Measure Angle dialog can now simply be used as a calculator, by entering any pairs of coordinates, representing a pair of planes, or a pair of linear features. Each time a number is entered through the keyboard, or changed using the "up" or "down" arrows beside each coordinate entry field, the result is immediately calculated and displayed in the dialog.
When you are finished, select Close to exit from the Measure Angle option.
Right Click Options
The Pole Snap option is available in the right-click menu, in steps 2 and 3 above, if you are using Measure Angle on a Pole Plot. This allows you to accurately "snap" to the coordinates of any pole on a Pole Plot.
Pitch Grid
The Pitch Grid option can also be used as a graphical method of estimating angles between features on the stereonet. However for precise answers, the Measure Angle option is recommended.