Distance Data Explorer

The Distance Data Explorer shows the pair-wise distance data. This explorer is flexible and it provides useful functionalities for computing within group, among group, and overall averages, as well as facilities for selecting data subsets.

This explorer consists of a number of regions as follows:

Menu Bar

File menu

Display menu

Average menu.

Help: This item brings up the help file.

Tool Bar

The tool bar provides quick access to a number of menu items.

· General Utilities

· $images\seq_data_explorer_diskette.gif$ : This icon brings up the Options dialog box to export the distance matrix as a text file with options to control how MEGA writes the output data.

· $images\edit_taxa_gp_button.gif$ : This button brings up the dialog box for setting up, editing, and selecting taxa and groups of taxa.

· Distance Display Precision

· $images\decimal_decrement.gif$ : With each click of this button, the precision of the distance display is decreased by one decimal place.

· $images\decimal_increment.gif$ : With each click of this button, the precision of the distance display is decreased by one decimal place.

· Column Sizer: This is a slider that can be used to increase or decrease the width of the columns that show the pairwise distances.

The 2-Dimensional Data Grid

This grid displays the pair-wise distances between all the sequences in the data in the form of a lower or upper triangular matrix. The names of the sequences and groups are the row-headers; the column headers are numbered from 1 to m, m being the number of sequences. There is a column sizer button for the row-headers, so you can increase or decrease the column size to accommodate the full name of the sequences and groups.

· Fixed Row: This is the first row in the data grid that displays the column number.

· Fixed Column: This is the first and the leftmost column in the data grid and contains taxa names. Even if you scroll past the initial screen this column will always be visible. To include a taxon in the data set for analysis, check the associated box. In this column, you also can drag-and-drop taxa names to sort them in the desired manner.

· Rest of the Grid: The cells to the right of the first column and below the first row contain the nucleotides or amino acids of the input data. Note that all cells containing data corresponding to unselected sequences or genes/domains are drawn in a light color.

Status bar

The status bar shows the sequence pair corresponding to the position of the cursor when the cursor is on any distance value in the display.