Selections

Introduction

To perform analyses on a subset of ranges, cores or locations, press the Make Selections button which is at the top of the third column in the analyses windows. If the button is not visible it either means selections cannot be made for the analysis chosen, or that the input file has not been chosen yet. Selections can also be made after pressing Modify for location files, this allows the creation of a new location file containing a sample of the data selected by attribute.

Pressing the Make Selections button opens a new window allowing selections. Pressing the Cancel or OK buttons at the bottom of this window will return you to the standard Ranges interface, and any selections you have made will be displayed in the ‘selections’ column.

The selections that are available, ranges, locations or cores will depend upon the input file type and the analysis being performed.

After selections have been made, click the OK button to apply the selections and return to the Ranges interface, click Cancel to the Ranges interface without applying any of the changes made in the selection window and click Clear to remove all of the selections made in the selections window, returning to the default state of all selected.

Selecting Ranges

In the selection window, range selections are made using the left and middle columns. Ranges can be selected by attribute in the left column, and directly from a list in the middle column. The name of the file from which ranges can be selected is displayed at the top of the middle column.

For both methods the list in the left column displays the range attribute variables of all of the ranges in the file, and shows which ones are currently selected (blue background).

Click the radio buttons select ranges by attribute and select ranges directly to switch between selection by attribute and selection from the list. Clicking on a line within the list also has the effect of switching select ranges directly on.

Range selection by attribute

When select ranges by attribute is not ticked, four range attribute tick boxes entitled age, sex, month and year will be enabled in the Range Attributes column.

These tick boxes correspond to four of the range attribute variables that can hold age, sex, month and year attributes of each range (although they may be set up to hold other attribute information).

By default these tick boxes are unselected and display the message all selected. This indicates that all attribute values are selected (or conversely that no ranges are being excluded based upon that attribute). All of the ranges in the list in the left column will be shaded blue to indicate they are selected, and the message Total selected should correspond to the number of ranges in the file.

Ticking one of the boxes will bring up a table of the range of values potentially available for that attribute. Initially none of the options will be selected (all of the table cells will be white), and this will mean that none of the ranges in the list will be selected (they will also appear white), and the message Total selected should be 0.

Click in attribute table cells to select values :

Left mouseclick	Select single values
SHIFT + left mouse click	Select a range of values
CTRL + left mouse click	Select multiple separate values

Any ranges that correspond to the selected criteria will become highlighted in the list of ranges.

If more than one attribute is selected, the selections are applied using an AND operator. That’s to say only those ranges satisfying all of the criteria will be selected, e.g. only females AND month 4 would exclude a male in month 4 or a female in month 3.

Range selection from the list

When Select ranges directly is ticked you can left-click within the list to select ranges from it.

Left mouseclick	Select single values
SHIFT + left mouse click	Select a range of values
CTRL + left mouse click	Select multiple separate values

The message Total selected above the table displays the number of ranges currently selected.

It is possible to choose a range attribute and then either add or subtract ranges from the list.

Selecting Cores

Analyses performed on edge files allow selection of cores if the edge file contains multiple cores. Multiple cores are present in some edge files - if for example the edge file has been created in Location Analysis using the option of selected cores or cores at 5% intervals.

Core selections are made at the bottom of the Range attributes column.

Overlap displays and habitat analyses can select to use a number of cores for each range, but analyses of overlap between ranges must select only one core at a time. Failure to select a single core in the latter case will result in the largest core being use by default.

Selecting by Locations

In the selection window, location selections are made using the right hand column. The name of the file from which locations can be selected is displayed at the top of the column.

Selections can be made based upon any location-qualifying variables (LQVs) that are stored in the location file. (LQVs store information about every location in the file).

For each LQV in the file three columns will be displayed.

Column 1	A tick box with the label of the LQV. Tick this to enable selection for that LQV.
Column 2	The minimum and maximum values stored for that LQV.
Column 3	If the corresponding tick box in column 1 is not ticked, this will indicate ‘all selected’. Otherwise it will contain an editable text box enabling you to enter individual values or sequences.

Note that LQV selections are not checked by the Ranges user interface, so if you type in values that exclude all locations, you will not be warned until the Run Analysis button is pressed, when a message indicating All locations excluded’ will be generated.

As for range selection, if more than one LQV is selected, the selections are applied using an AND operator. That’s to say, only those locations satisfying all of the criteria will be selected (e.g. only those active AND between the hours of 21:00 and 23:00).

When subsets of the data are being repeatedly run, rather than make those choices all the time it is better to create a file of just that subset. Likewise, using just a subset can reduce analysis time. For information on the ability to filter the data and make a subset file see Modify (filtering locations)