This section describes the mechanics of entering a cost matrix. Cost matrices are entered at the top of the PVM console area of the htool window in the scrolling region reserved for them. The File and Edit menu buttons in this area operate on cost matrices.
The easiest way to enter a cost matrix is to leave it blank until your HeNCE graph is completely drawn and all node programs are entered. At this point, HeNCE will know the names of all subroutines that are called from computation nodes. From the PVM Console Edit menu, select ``Add from Graph'' and a row for your first host will be added to the previously empty cost matrix. Fill in the host name and all costs for this row. Then pick ``Add from Graph'' to create the row for the second host, and so on.
When the matrix has been entered, save it into a file by picking ``Save'' from the PVM Console file menu. Do not forget to do this before exiting htool. The cost matrix is not automatically saved. By convention cost matrix files end with ``.mat'', but this is not required.
To enter text into a field within a cost matrix, simply move the mouse to the field and type. The text will appear. Use the delete or backspace key to erase characters. Some other cost matrix manipulation functions follow.