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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

Memory Usage

Lists of stress data for a stress period require special consideration because MFI does not require the maximum size of a list to be specified. MFI allows the user to enter list data of varying length, and the length can change at any time. In order to store lists of varying size, MFI allocates memory for lists in blocks. Each block has a fixed size, but a list can consist of up to 10 blocks.

The following parameters control how much memory MFI can use. These parameters are defined in the file "mfi.gbl," which is an include file used in many of MFI's subroutines. In addition to the size of the X array, these parameters specify the sizes of a number of other arrays used by MFI to keep track of data.

LENX -- Number of elements in the X array

MXVAR -- Maximum number of parameters

MXARR -- Maximum number of parameters that are arrays

MXFNAM -- Maximum number of files

MXLIST -- The number of entries in a list block; a list can consist of up to 10 blocks