What's New for IPW Programmers
For version 2 of IPW, numerous changes and additions were made to the
original version in order to advance the project further toward these
objectives:
- minimize time and effort required for maintenance, and
- maximize portability.
From a programmer's perspective, this is what's new in version 2:
-
Integrated original IPW library with ERLC library (the library developed at
the EPA research lab in Corvallis, Oregon), and separated into
two new libraries based on functionality instead of site: libipw
and libmodel:
-
libipw contains all the library functions related to IPW images
-
libmodel contains all the functions for physical modeling
-
GNU's autoconf was utilized to produce the configure script.
This simplifies the configuration process, and makes it easier to install
IPW on new types of systems which conform to system requirements listed in
the System Requirements.
-
Grouped IPW commands (called "primitives" in the original version)
into categories by topic to facilitate user and programmer understanding
of the available commands.
-
All source code is now compatible with the ANSI/ISO standard for the C
programming language.
-
Expanded the use of include files for GNU make to simplify
individual Makefiles.
-
Added a standard target called help to all the make
include files. When the programmer specifies this target for the make
command, a list of available targets is displayed.
-
Separated the manual page documentation from the source code files to allow
editing of documentation without confusing make into thinking
that the source code needed to be recompiled.
-
The single source file for manual page is used to build two versions of
manual page: troff version for use with Unix man command, and a HTML
version for use with Web browsers. The single file insures consistency
between both versions of the manual page.
-
Manual page documentation for IPW commands published on the Web to allow
interested people to see what IPW software offers, and to evaluate it
in terms of their own needs.
-
Allows a site with IPW version 2 installed to use the Web versions of
the manual pages as their local on-line documentation for IPW.
-
The name and one-line description for each IPW command are now kept
in a single place (i.e., in the command's Makefile) to ensure that
the command's manual page is consistent with command lists (such as
those displayed by the ipw command).
-
Manual pages for library functions are also treated the same as commands'
manual pages: troff and Web versions are both derived from a single source
file.
-
X/Open's Single Unix Specification was adopted as the standard for the
target Unix system for IPW.
-
Several new libraries developed:
- one for energy-balance snowmelt model (libsnobal)
- one for General Cartographic Transformation Package (libgctp)
- one for a higher-level interface to IPW images (libimage)
- one for using string options for commands (libstropts)
IPW documentation /
Last revised 29 May 2009 /
IPW web site