Geo @ ObjectGraph

Earth and Environmental Science Blog

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Archive for November, 2010

Google Fusion Tables Tutorial


Google launched a new service it’s called “Fusion Tables“. It looks like their spreadsheet but it’s more powerful. Unlikely other failed Google Projects, I see a lot of potentials because Google is always good at automating process (while other manual or human interaction based services were failed – e.g. Orkut or Google Answers) . The second reason is because professional users are willing to pay some cash for extra storage and CPU power and Google is one of opinion leaders in the cloud computing market. This service could be competitive against other professional GIS platforms in the next Web X.0 generation. ESRI start moving towered more REST base web service platform with their rich toolboxes. Other web based services, such as Spatical Key or MapBox could be another competitor for visualization market. I did not try them but I often see interesting projects from them. Since Google already has good platform like Google Earth / Map, I wish they polish both authoring and reporting environment for GIS users.

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Python and Geometry


GDAL/OGR is a handy and heavy duty geometric library in Python. If you use any GIS systems, you often see “Python Console” which allows you to calculate complicated spatial computation. In GIS software, you can do this using your mouse (e.g. ArcGIS Toolbox and Spatial Analysis Extension); however, you need this technique if you need to customize or automate the process. I start using this library since I’m taking GIS course at Long Island University. In this blog entry, I would like to have an introductory tutorial how to handle geometry in Python using GDAL/OGR. If you do not have a Python setup, the easiest way is to open up Python Console window in GIS system. ArcGIS has python console but if you do not have access to ArcGIS, I recommend to use QGIS which is an open source software for free and it’s available for various platform. Since I’m using Mac, I’ll show those examples on QGIS below.

Download QGIS

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In this semester, my professor handed out an interesting homework about finding fractal patterns in nature shapes. Fractal is mathematical patterns which seems to be appearing at random but it starts revealing repeatitive features as you zoom in / out. For example, you can find fractals in galaxy, brain’s neuron, and shorelines. They all look same if you zoom in one part. Once you zoom again, they show similar shapes. If you zoom in a edge in a coastilne, you will see similar patterns of zig-zag shapes again. If you zoom out, you will see similar shape in the big picture.

Fractal and Zooming - Image Source: Wikipedia

Benoît Mandelbrot

Oddly, when we started this homework, Benoît B. Mandelbrot just past away in the same week. He is a famous mathematician from Poland and he did great research about mathmatical aspects of fractal. Since my graduate course is about GIS topics, we are excersizing on computer but this homework assignment does not require any digitized media. If you are curious about this problem, please try this at your home.

Coastlines are fractal or not?

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