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I'm trying to detect the z value for adjacent contour lines, compare them and determine if there are any missing contours in the data.

 

Using a Coordinate extractor to create a z height attribute, then a neighbor finder with all data entering the candidate port I can't get the attribute from the nearest candidate to copy across.  I then attached the data to both the Base and Candidate ports, renamed the coordinate extracter z heights to z_cand and z_base. This gave me the two attributes but they were the same value and the distance to the candidate was always zero showing the base and nearest candidate are the same element. 

 

 

I've tried using a TIN generator to get the Z_min and Z_max of the triangles but with very large data sets this often results in a hung translation.  I need a simpler approach.

 

 

Cheers,
Hi,

 

 

I'm guessing that there are multiple lines having same z-value and touching each other at the end node. If so, the LineJoiner (Group By: z) can be used to connect them into a single line.

 

 

Takashi
Hi I used this bit in a scrip to create waterlevelcharts.

 

 

It basical creates adjacent planes of contourlines.

 

with a little adaptation u can identify neigbours. It also extracts z ranges of each "sloping terrace" as i called it in the script.

 

Maybe it is usefull to u?

 

 

It basicaly creates relation to adjacent levels (contours). Use a list in the Areabuilder and you have the relations to each neighbour.

 

 

Gio,

 

Thank you for your response.  I’m having trouble getting good response from your script. I think what you are doing is creating polygons from adjacent contours by joining the ends using the Hull Accumulator, intersecting the Hull with the contours and then building Area features.  The problem I have is that the Hull Accumulator and Intersector  are not working in 3d and when the polygon is created the hull segments aren’t topologically correct in Z.   My idea was to create the polygons, extract the Bounds and evaluate the expression _zmax - _zmin  must be equal to some contour interval (in this case 2).  But the odd z heights of the hull segments is throwing this method off.  Do you experience this same problem?

 

 

I’m using FME 2012 build 12238

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