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I need to assign a point value in raster format to a raster stream segment, which contains the point. See bellow:

Point values and stream segments

The expected result is a segment, whose value is the point value. How could I?

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up vote 3 down vote accepted

One method is to use the segments as zones and request zonal statistics for the point values. Provided there is at most one point per segment, many statistics will work, including max, mean, sum, and min. When there is more than one point per segment, you will need to decide how to combine the point values, but zonal stats is still a good candidate for a solution method.

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I've tried zonal statistics but it resulted a stream point feature rather than line. I don't know why... –  Werisk_ Sep 18 '12 at 17:41
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Exactly how did you "try" the zonal stats? What command did you use? (Indeed, what software are you using?) Depending on the software and the command, you will get either a new raster for the results or a table: it's not possible to get a point feature layer as an output using zonal stats. –  whuber Sep 18 '12 at 18:21
    
First of all thank you for your attention. I'm using the ArcGIS 10 and the command Zonal Statistics. I don't know why but it returned a lot of points in the same shape of the stream network. =/ –  Werisk_ Sep 18 '12 at 21:51
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OK, that's mysterious. Exactly how do you represent the stream network? Based on your illustration I assumed each segment is identified by a unique (integral) value. That's an important prerequisite for using zonal statistics. Is that the case with your grid? –  whuber Sep 18 '12 at 22:38
    
For any reason I could use Zonal correctly and result is fine right now...go figure! Thank you guy! –  Werisk_ Sep 18 '12 at 22:52
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