Beyond and side by side with numerics

The 23rd of april was quite busy for me. Early in the morning I gave a tak of acouple of hours to the students of Numerical Analysis.  My goal was actually to try to capture their interest about the topics I cover in my research, which I considere complementary to good numerics.

For supporting this idea, I divided my presentation in two parts. The first under the motto: the right numerics, for the right equations. There, I showed how Richards equation can be modified to account for transition to saturated conditions and  for freezing soil. This last part has been largely derived from the work of Matteo Dall'Amico (here his Ph.D. thesis) and the subsequent paper on the Cryosphere journal. With the benefit of hindsight, I can tell that I could have been much more clear on the physics of the problem, but it was just doing the presentation that I realised it.

The second part is dedicated to justify the rational of what I called "The Geoframe project", which is an integrated system for doing hydrology by computer, completely open source, and which has a deployment in the JGrass-NewAGE system. Click on the painting above  to see the presentation. 

Hydrology at Vicenza

Here you can  find the presentation I gave  in Villaverla next April 23th. What I did was collecting many information about the hydrological cycle and its extremes in the Northern Vicentino (Provincia di Vicenza).
I feel proud having been invited to talk in my home town about what I do, and I hope I have not betrayed the expectations. In my presentation. I used pretty much the work of colleagues Andrea Rinaldo, Giulia Passadore, Mario Putti, Marco Borga, Lorenzo Marchi, of the officials of River Authority of "Alto Adriatico" and of others. You can find the presentation by following the link behind the image below (click on the figure).

Hope You enjoy it.

A concise introduction to the uDig GIS

It mainly derives from the uDig site.

The goal of uDig is to provide a complete Java solution for desktop GIS data access, editing, and viewing. 

uDig aims to be:

• User friendly, providing a familiar graphical environment for GIS users;
• Desktop located, running as a thick client, natively on Windows, Mac OS/X and Linux;
• Internet oriented, consuming standard (WMS, WFS, WPS) and de facto (GeoRSS, KML, tiles) geospatial web services; and,
• GIS ready, providing the framework on which complex analytical capabilities can be built, and gradually subsuming those capabilities into the main application

The above explain the name. However it also:

• Works with .shp and companion files for what regards vectorial data (simple features, according to OGC)
• Easy connects with Databases either commercial, or free like Postgresql/Postgis and MySQL
• Interoperates with GRASS commands through the Spatial Toolbox
• Treats  GRASS raster data well as geotiff, jpg,  and the most common raster formats 
• Includes a very powerful map calculator based on jiffle

For what I more or less directly contributed, it embeds in the Spatial Toolbox:

• A very complete suite of tools for doing terrain analysis (pit removal, basin delineation, network extraction, contributing areas calculation etc for more that 50 complex operations) 
• Some hydrological models (like a GIUH model called Peakflow which includes some peculiar features, a distributed model system based on OMS3 components called JGrass-NewAGE, which in turn uses a Kriging component for interpolating rainfall or other quantities (and other interpolators),  a component for the estimation of solar radiation that accounts for shadows and clouds, a rainfall-runoff module, a propagation module, and others components
• Some shallow landslide modelling with SHALSTAB and others simple tools for estimating the extension of debris flow run-out

For what is probably a unique feature, it also gives a GIS interface to (unfortunately, the documentation is still in Italian):

•  EPANET for the verification of water supply systems
• Trento_p, a model based on the GIUH for the design of sewer systems and culverts

Certainly I am forgetting something. Among the prototypes produced, there were:

• An interface to the NASA World Wind Globe
• A treatment of netcdf

These last experiments are not anymore operational but they show the potential of the project which will be exploited when the adequate funding will be raised.

Recently uDig became parts of the Eclipse Foundation Project through the Location Tech initiative. 

Documentation in English can be found here. In Italian instead here.

The Horton Machine

The Horton Machine is the place where, during the years, I conveyed my tools for the treatment of Digital Elevation Models, which where used in my past research in hydro-gemorphology, and hydrological modelling. Before using it, certainly, it is better that you read the previous post about uDig.

• An introduction to the analysis of DEM for their use in hydrology can be found here
• The Horton Machine manual is still splitted in two parts which will be merged as soon as we will be able to o it
• The tutorial  (a draft in Italian, but looking at the figures can be useful - 38Mb: we are working at its translation and merging with the reference manual in a future publication)
• The old reference manual which also have some bibliography.
• If looking to the youtube/uddigis channel and reading the help of the Spatial Toolbox you succeeded in running it below you will find a data set where to make some practice: the  rio Valpiana (100 Mb)

• Here you can find some R-scripts which can be useful to plot and analyse the results of some uDig elaborations (by Leonardo Perathoner): 
• how to plot the distribution of the values of a map
• how to extract the table of attributes from a shapefile

For your curiosity following the next link, you will find the cost of what you have learned so far, once taught in a commercial environment (that you have to pay separately).

To come: the documentation of the GIUH model Peakflow, of the semi-distributed model components of the Jgrass-NewAGE system, and of our implementation of SHALSTAB, that are, actually included in the Horton Machine.  Further information can be retrieved also at the Horton Machine site.

uDig/Jgrasstools resources (in English)

uDig is very much a product for developers, but it can be also a valuable tool for users.
To know what uDig is and does, you can look at this post.
To use uDig, the first thing is to install it, following the instructions at the GIS website. After this first installation,  install the Spatial Toolbox. Now you can think  how to use it !
uDig pages are actually full of information, but I took a little of time to summarise them here too, and also to add some resources that are not available in the official website.
If you do not know what a GIS is, look first at:

• Introduction to GIS (well, for a more structured introduction, a very good introduction is de Smith et al., Geospatial Analysis a comprehensive guide, 2013 - which is available on-line)


• A presentation (just a little out-of-date) to jgrasstools and uDig
• Walktrough 1 - Installation of uDig 1.4.0
• Walktrough 2 - Editing in uDig and WFS
• To know how to work with map look at YouTube/udiggis
• Using the Spatial Toolbox
• Still in Italian:  Working with GRASS (but is going to be translated: is it true Aroon ?)
• Using the Map Calculator  by exploiting Jiffle (here its manual).

• The material about the tools to work with the Horton Machine is now in a separate post (and is still partially in  Italian).
• The material to support the culverts, and sewer systems design as well as the documentation of the nettools for the design of water supply system is instead here, but in Italian.

For learning about the scripting capabilities of uDig, one can give a look at:

• to the post by Andrea Antonello on JgrassTechTips (which is a further source of useful information)

The new version of uDig support also geoscripting, and how, it is explained here.

In any case do not forget the screen-casts at:

YouTube/udiggis

For who could help, please give a look to the post by Andrea Antonello.