6 NetpathXL—An Excel
Interface to the Program NETPATH
One additional option (<F>ont) has been added to the
main screen (fig. 5). Typing “F” at the main-screen prompt
will result in queries for font height, font brightness, and
background brightness. The default font size is 16; specify-
ing a smaller or larger number (8 to 24) correspondingly will
decrease or increase the font size used for painting the screens
in NetpathXL. The default font brightness is 0.85; decreasing
or increasing the number (0.3 to 1.0) correspondingly will dim
or brighten the font. The default background brightness is 0.25
(midnight blue); a value of 0 will produce a black background,
and a value of 1.0 will produce a bright blue background.
Summary and Conclusions
NETPATH is unique in the capabilities it provides for
geochemical inverse modeling and radiocarbon dating of
ground waters. NetpathXL is a partial modernization of the
program NETPATH. NetpathXL simplifies data input by using
a fixed-format Excel spreadsheet in place of the program
DB. File browsing, installation, and concentration data input
have the look and feel of current computer programs. The
model-development process remains unchanged from that of
NETPATH and requires keyboard input rather than point and
click technology. However, keyboard input is efficient and the
model-development process is simple and straightforward. The
calculation engine in NetpathXL is identical to NETPATH.
New capabilities have been added to allow the inter-
change of data from NetpathXL to PHREEQC and from
PHREEQC to NetpathXL. DBXL can translate a NetpathXL
spreadsheet file to PHREEQC format (.pqi). PHREEQC can
translate solution compositions to a NetpathXL .lon file. In
addition, each inverse model derived by PHREEQC can be
written to NetpathXL .pat and model files, which allows the
PHREEQC inverse model to be reproduced in NetpathXL.
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