Qt4 components. Qt is free and open source framework. PyQt4
is a Python binding of the cross-platform GUI toolkit Qt4. Like
Qt4, PyQt4 is a free software.
For the development of graphics display plugin Qgis, Qt4 and
pyQt4 libraries have been used. The necessary files of a QGIS
plugin and their structure is as follows:
PYTHON PLUGINS PATH/
myPlugin/
init. py
plugin.py
resources.qrc
resources.py
form.ui
form.py
where init .py is the starting point of the plugin, plugin.py
is the main working code of the plugin, resources.qrc is the
xml document created by Qt-Designer, resources.py is the
translation of the .qrc file described above to Python, form.ui is
the GUI created by Qt-Designer and form.py is the translation of
the form.ui described above to Python.
Figures 4 and 5 display the flowchart and user interface of the
developed plugin of a single module out of various as sample.
In places where sensitive parameters need to be changed
frequently to get desired results, the plugin allows the user to
change them during runtime in a simple manner. As such the
time required to make the changes in the actual parameter files
was saved.
NBSS&LUP,
sa DEM FAO SOIL
MAP
Y
—— » OVERLAY = + SUBSET,
REPROJECT
Y AE Y
AVG ANNUAL MEAN DOMINANT
PRECIPITATION ELEVATION OL Tory /4—À] OVERLAY
IN EACH GRID FOR GRID
GRID
Y
soil
PARAMETER
" FLEINASCH /*
FORMAT
Figure 4 Flowchart to create soil parameter file
INPUTS
GRID MAP: | a Browser
SOR TEMAS | erem | Browser |
AVG. RAINFALL MAP: m si ; T : is : -| Browser
PARAMETERS FILE: | | Browser
OUTPUT SOIL PARAM FILE: | | Browser
Help Cancel OK
Figure 5 User Interface to generate Soil Parameter file
5. CONCLUSIONS
It can be concluded that the tool for hydrological modeling
through VIC model FOSS4G specifically allows users (i) to
generate VIC input files rapidly, (ii) to change calibration
parameters during runtime and (iii) provides a user friendly
manner of dealing with otherwise, a very data intensive and
time consuming issue. A potential of QGIS allowed
customizing in such an casy and efficient manner to develop a
tool that is the best in its domain. The plugin also allows further
modifications to be made in order to enhance its efficiency to
any other area of interest.
Lastly, this study proves that use of FOSS tools and software
libraries have an upper hand over proprietary GIS tools when it
comes to developing custom user-specific applications for
hydrological modeling. Future works in this area can be
concentrated on merging the benefits of semantic assimilation
of datasets so as to avoid programming overheads in data
conversion.
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Steiniger, S., é
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ACKNOWLED
This work is
Organisation — (
are due to Dr P.S
S. K. Srivastav,
guidance, suppo
(HT-H) and Dr
GUI dev and VIC
