Hi Mark
   
  Thank you for you message
  Regarding my second question, I'm not sure what the CoordinateFetcher is 
doing in the process, I'm not sure where to put it? Since I need to put the 
average elevation back to the points should I connect Point or Area output from 
PointOnArea to Aggregator? And last (but not least J) I'm not sure how to 
include FeatureMergerÂ…who is requestor and who supplier?
  Overall, could you send me an example workspace it would be of great help. 
And in the end of the process I need to put the average elevation back to the 
points witch are inside the polygons.
   
  Thank you VERY much for your help


mark2atsafe <[EMAIL PROTECTED]> wrote:          Hi,
In answer to your questions...

--- In [email protected], "jeka.trud" <[EMAIL PROTECTED]> wrote:
>
> Hi
> 
> I have streams that pass through points. I tried to choose the 
> nearest points with POINTONLINEOVERLAY, but did not give me good 
> results. Sometimes it did not choose the points, and they were near 
> and sometimes it choose too many points. I need only nearest point. 
> How can I attach jpeg it would explain more? 

You might find the NeighborFinder transformer is the better one to try
here. PointOnLineOverlay will only find points within a specific
tolerance; NeighborFinder will find the closest point regardless
(though you can set a maximum distance tolerance)

> I have another questionÂ….sorry I'm FME novice :(
> I need to extract the points witch are inside the lake polygons. The 
> points have different elevation (Z coordinate). I need to calculate 
> average elevation inside of every polygon, taken from points and 
> then assign that elevation to points. 

There are two transformers that will calculate an average value, and I
think the Aggregator is the one that will work here. The steps are as
follows.

1) I assume your lake polygons have a unique name or ID? If not use a
Counter to create one. 
2) Use CoordinateFetcher to get the Z for all point features. 
3) Use the PointOnAreaOverlayer to copy the lake ID onto the points
that fall within it. 
4) Use the Aggregator to aggregate the POINT features. In the settings
set ID as the attribute to average. This will give you a single
feature (an aggregate or MultiPoint) containing the average Z value. 
5) If you need to attach the values back onto the lake polygons then a
FeatureMerger (again using ID as the join attribute) will do this very
simply.

Hope this helps. The Aggregator "average" setting is not one you see
used very often, but which can be quite useful. When we get a group-by
option on the StatisticsCalculator then it would make this simpler still.

If you do have problems with the lake Z averager then let me know and
I'll see if I can create an example workspace.

Regards,

Mark

Mark Ireland, Senior Product Specialist
Safe Software Inc. Surrey, BC, CANADA
[EMAIL PROTECTED] http://www.safe.com
Solutions for Spatial Data Translation, Distribution and Access



         

       
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