Spatial Solutions Architect and Database Expert
Simplifier is a Manifold Map script that implements a set of different methods for topological simplification of a planar-enforced polygon drawing. The code (map file) can be downloaded here To understand what it does see the presentation on Gridding and Simplification (Presentation on techniques for modifing/splitting of large polygons that demonstrate slow performance when beingRead More
This article is not about Oracle Locator/Spatial but simply about the use of some of Oracle’s Relational On-Line Analytical Processing (ROLAP) functionality in building reports for publication with a range of software from Apex to Crystal Reports. The context for this is that I regularly am hirecd to write ordinary financial reports for the DepartmentRead More
I had someone contact me the other day and ask: “I find your articles very helpful and interesting. I was wondering if you can guide me to a link or something that may contain how to figure out surrounding blocks to a given block.” I am assuming that the person wants to know how toRead More
I gave two presentations at the Australian Oracle Spatial Forum held at the Novotel Hotel, Sydney Olympic Park on Thursday 28th August 2008. My two papers were: Automated Layer Management – Experiences At Mid Coast Water Gridding vs Simplification in Extracting Performance from High Density Data The first was co-authored with Mr Brendan Soustal thoughRead More
(WARNING: I have completely re-written my centroid code since this article when I discovered that the algorithm I had been supplied by a Tino failed in one important case. Instead of fixing the existing algorithm I completely re-wrote it and have also added support for polygons and mutil-point geometries. I will edit all centroid relatedRead More
This technical blog article describes the benefits in using pipelined functions in Oracle to manipulate sdo_geometry objects. In doing so it will describe a number of functions available in the COGO and GEOM packages in the PL/SQL packages I make available for a free download from this site. What I will do is introduce aRead More
This little article was occasioned by someone emailing me and asking: Actually I do have a topic for you – clustering. Before we moved to Oracle Spatial, we had a request for a client to: “Show us all the stores that are close to each other”. I’m somewhat embarrassed to say that we did this byRead More
Ever wanted to know what a decimal degree was in meters, nautical miles or feet? It is something I often need to do in Oracle so I decided to do something about creating a function that would do this. This involved me having to hack my way into some of the mdsys coordinate system andRead More