This function reads a text file in Epanet's .inp format
and returns an S3 object with entries for
sections of the .inp file. Sections of the .inp file that are implemented
appear in the Value section.
Fields for node or link ID are stored as characters not factors or integers.
However, some fields are stored as factors
to allow more informative summaries. Examples include valve type and pipe status.
Sections that are absent from the .inp file are NULL in the list.
Columns of data.frames use the headings exported by
the Epanet GUI.
The [OPTIONS] section in the .inp file is used to update
a list of Epanet's default options. In this way if an option such as
units is not specified by the .inp file, the units that would be used by
default are provided.
In the [PATTERNS] and [CURVES] sections, integers used as names of list elements are backquoted
according to the default behavior in R. So if the .inp file has a pattern "1"
this pattern will appear as element `1` in the list that is returned. A warning is issued in this case.