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This is an umbrella task for some coordinate operation methods not yet supported in Apache SIS. Coordinate operations include map projections (e.g. Transverse Mercator, Lambert Conic Conformal, etc.), datum shifts (e.g. transformations from NAD27 to NAD83 in United States), transformation of vertical coordinates, etc. We can of course not list all possible formulas that we do not support, but this JIRA task lists at least some of the operations listed in the EPSG guidance notes.
The main material for this work is the EPSG guidance notes, which can be downloaded freely from the following site:
IOGP Publication 373-7-2 – Geomatics Guidance Note number 7, part 2
Coordinate Conversions and Transformations including Formulas
http://www.epsg.org/GuidanceNotes
Google summer of code students interested in this work would need to be reasonably comfortable with the Java language (but not necessarily with the JDK library at large, since this work uses relatively few JDK classes outside Math), and in mathematic. In particular, this work requires a good understanding of affine transforms: their representation as a matrix, and how to map a term in a formula to a coefficient in the affine transform matrix.
Apache SIS has one advanced feature which is not easily found in popular geospatial software or text books: the capability to compute the derivative (or more precisely, the Jacobian) of a transformation at a given point. Implementation of this feature requires the capability to find the analytic derivative of a non-linear formula and to simplify it.
Implementations of those formulas take place in one of the org.apache.sis.referencing.operation sub-packages (projection or transform). Implementations of JUnit test happen partially in Apache SIS, and partially in the "conformance module" of the GeoAPI project, if possible through the Geospatial Integrity of Geoscience Software (GIGS) tests.
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Hi Martin,
My name is Ndangoh Joseph S, a third year undergraduate in the university of Buea Cameroon, studying computer software engineering. I found this project interesting and i will like to participate in gsoc 2016 to contribute to this project.
I have good programming skills in java, java spring framework, javascript and c. I am currently working in an emerging startup, Skylabase Enterprize(http://www.skylabase.com), as a software developer.
I have read the project idea and have seen the open issues and also the appreciable work you have done. I am going through the documentation here http://www.epsg.org/GuidanceNotes, inorder to understand the project better.
Please guide me on what to do next.
Thanks
Ndangoh Joseph.