Measure Distance Between an Array of Points?

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Measure Distance Between an Array of Points?

IIIMurdoc
I am measuring changes in a complex shape (Nautilus Shell X-Rays)  over many many specimens.  
Since they are all the same general shape and only vary in proportions and scale, does anyone know of a plugin that allows me to set a certain template of points where each point can be moved to fit unique examples, and then take measurements of the distances between those points?

And If this does not exist, is it possible to take measurements between multiple points in one go.  
Also, if it does not exist already, I am looking into how to code such a plugin and any advice on what to look into would be appreciated.

Basically I want a plug in that has about 6 points that can be moved via the mouse, and measures the distance between certain different points.

Bonus points for one that comes pre-formed to a general shape that only needs modifying for specific animals
Bonus points for a sort of Magnetic line selector that can trace round but well defined edges

Thank you
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Re: Measure Distance Between an Array of Points?

Marcel
Yes you can define your template as a selection in ImageJ (bonus point 1) and and then add this selection to the ROI Manager of ImageJ.

With the ROI-Manager you can a kind of record your selections and then later restore them from the list of the ROI-Manager. ImageJ offers several selection tools for a predefined shape in the Edit->Selection menu.

For the measurements of interpoint distances it is easy to use ImageJ in combination with R.

http://www.r-project.org/

The software Bio7 (sorry for this self-advertisment) offers interfaces between ImageJ and R and offers some methods to transfer ImageJ selections and images to R.
It is available for the OS Windows and Linux.

http://129.70.40.49/modelling/?page_id=75

In addition Bio7 has integrated some functionality to transfer single selections (the point coordinates as vectors) and multiple selections (from the ROI Manager as 2d lists) directly to the R workspace.

If the R package (plugin) "spatstat" is installed you can use the methods nndist (nearest neighbour distances) or pairdist (distances between all pairs of points in a point pattern) to analyze your shapes and also do easily summary statistics and more.

http://www.spatstat.org/

I integrated this functionality in Bio7 to support morphometrics for plants and animals.
For more Morphometrics with R have also a look into this book:
http://www.springer.com/statistics/life+sciences,+medicine+%26+health/book/978-0-387-77789-4
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Re: Measure Distance Between an Array of Points?

Marcel
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Re: Measure Distance Between an Array of Points?

IIIMurdoc
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Great!  Thank you!  Watching the screencast this looks like it could be exactly what I need.  
I was kind of hoping I would be forced to code something, but as usual, someone has already done it better than I ever could:)