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A Data Input Program (MFI) for the U.S. Geological Survey Modular Finite-Difference Ground-Water Flow Model
U.S. Geological Survey Water-Resources Investigations Report 94-468

Entering Data with the Spreadsheet Program

MFI uses a separate spreadsheet program to allow the user to enter two types of data. One type is data that corresponds to every cell throughout a model layer such as transmissivity. The values are displayed and edited as a spreadsheet table; the cell locations are implicitly designated by the row and column locations in the table. The second type of data for which a spreadsheet is used is a list of data in which each entry in the list includes a layer, row, and column grid location plus one or more parameters that apply at that location. An example of such a list is the list of wells for a particular stress period. For each well, there are four values, which are the three grid coordinates plus the well recharge rate (negative value indicates pumping). If MODPATH is being used, each entry also includes a code to indicate the face through which the stress is applied. The spreadsheet includes column headings that define the parameters to be entered.

The spreadsheet program is automatically activated when needed. Once activated, the user edits the data, saves it, and quits the spreadsheet using the spreadsheet commands. When the spreadsheet program quits, MFI reads the data saved by the spreadsheet and continues processing.

As documented in this report, MFI uses the Tactician Spreadsheet program by Soft-tek. User instructions for Tactician are not included here; it is assumed that users of MFI will refer to appropriate user manuals for this information. The file "tact.t" is temporarily used to hold the data being edited by the spreadsheet. When done editing the data, the user must save the modified data into the same "tact.t" file. Then the user should exit the spreadsheet. After the spreadsheet program quits, MFI reads the modified data from "tact.t" and deletes that file.

MFI would have to be modified in order to use a different spreadsheet program. Information about program modification is contained in the Program Documentation Section.

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