Sample menu

New Sample... (command N):
Brings up a dialog box showing all of the samples in this locality; any locality can be selected by double clicking on it, clicking on it and clicking "OK" (or hitting return), or using the up and down arrow keys to highlight the desired sample and clicking "OK." The number keys will also move the selection down that number of samples. You can stay with the current sample by hitting "Cancel." The points selected for the new sample are those of the same position as the old sample (i.e., if you had selected points D-H in the old sample, points D-H will be selected in the new sample even if they represent different demag steps).
Next Sample (command =, which is the same as command + on the main keyboard):
Opens the sample after the current one in the list in the .SAM file for analysis. All open windows are adjusted for the new sample. The points selected for the new sample are those of the same position as the old sample (i.e., if you had selected points D-H in the old sample, points D-H will be selected in the new sample even if they represent different demag steps).
Previous Sample (command -):
Opens the sample before the current one in the list in the .SAM file. The points selected for the new sample are those of the same position as the old sample (i.e., if you had selected points D-H in the old sample, points D-H will be selected in the new sample even if they represent different demag steps).
Least Squares Fit... (command L):
Brings up a dialog box allowing you to fit the currently selected points with a line, plane, or circle in a least squares sense. Note that no points are initially selected when the program first opens; you will not be presented with a dialog box if 0 or 1 points are currently selected. You are not allowed to fit a plane with only 2 points. The "fix to origin" option is only permitted if the origin is selected (which can be done by checking the "Include Origin" box). The mathematics of the fitting process are beyond the scope of this document; see Kirschvink [1980] for the details.

The computed direction (in geographic and stratigraphic coordinates) is displayed along with a scrollable pane with all the previous least squares picks for this locality. You can view the old directions either by the order in the .LSQ file ("File"), the sample number, or the three letter code assigned the fits (ID). Previous fits for this sample are highlighted and the last of these fits is centered in the window. You can select fits to delete with the "Delete Selected" button by point-and-click techniques, but remember that until you deselect them, all the fits of the current sample are selected. You are notified how many picks you will delete and asked to verify this; after this, the window again highlights any fits of the current sample. The fits selected for deletion will actually be overwritten and lost forever only when you next save a least-squares fit. If you assign the same 3 letter code to a fit as a fit for the sample already in the .LSQ file, then you will be asked if you wish to replace the previous fit. If you say yes, this direction will replace the old direction at the same line in the file.


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