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Hi all, I am unable to use raster calculator after an iterator in model builder. I've read endless threads on this subject, but am still unable to get it to work. I'm trying to build a simple model: iterate rasters, collect values, raster calculator (see attached). However, when I try to connect the output values from Collect Values to Raster Calculator, the only available option is to connect them as a precondition. Any advice would be greatly appreciated. If I can figure out the first step, I'd like to use raster calculator to convert the NoData in each raster to 1, using this expression: Con(IsNull("raster1"),1,"raster1") How can I get the tool to run this iteration for each raster? If I use "%name%", will it work? Thanks in advance. Cheers, Heather
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02-10-2015
02:02 PM
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Hello, I need some help thinking my way through a raster analysis. Any suggestions would be greatly appreciated. I have a series of rasters, and I need to perform two operations: 1. Calculate the median for each pixel across all the rasters 2. Move to a coarser resolution (with pixels roughly 2x as big) using the median I realize I could use cell statistics for step 1, and aggregate for step 2, but what I'd like to do is perform both operations in the same step. For example, if I have 10 rasters with pixels that are 1x1km, in one step I'd like an output of 1 raster with pixels that are 2x2 km, where the value of each pixel represents the median value across 40 pixels (4 pixels per raster to change the resolution by 10 rasters). I guess to put it another way, what I'd like to do is find the median of a cube of pixels. One idea I had for how to do this is to use the cell statistics tool, but under environments enter the coarser cell size. This would accomplish both steps at once, however I'm unsure what statistic the tool would use to change the cell size. I'm assuming it would probably use the mean, which wouldn't work in this case. Alternatively, I have a separate raster with the correct pixel size. Is there a way I could use this raster as a 'zone' to calculate statistics across multiple rasters? This would be like using the zonal statistics tool but across several rasters as opposed to one. Thanks in advance, Heather
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04-09-2014
09:31 PM
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Hi Josh, Thank you so much for your response, and sorry mine is so late (I've been out in the field and away from internet). As you suspected, import arcpy failed and I've had to reinstall GIS. Fixed the problem! Thanks for the help. Cheers, Heather
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04-06-2014
03:10 PM
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Hello, I've searched the discussion forums but have been unable to find a solution to my problem... I recently installed a new version of GIS (10.2). I had an old version of python (2.6) on my computer, and so the GIS installation included a new version of python (2.7, 32bit). I needed to install a new version of Marine Geospatial Ecology Tools (MGET), which requires python and pywin32 to run. The MGET installation found the two versions of python in the registry and kept failing to install properly, so I deleted all versions of python and pywin from my computer to start fresh (which I'm now thinking was a big mistake). I reinstalled python (2.7.6, 32bit) on my computer here: C:\Python27. But now when I run a GIS tool that needs access to arcpy, say Raster Calculator, I get the following error: ERROR 000539: Error running expression: rcexec() Traceback (most recent call last): File "<expression>", line 1, in <module> File "<string>", line 2, in rcexec File "c:\programe files (x86)\arcgis\desktop10.2\arcpy\arcpy\__init__.py", line 33, in <module> import arcpy.utils as utils AttributeError: 'module' object has no attribute 'utils' I'm thinking that GIS is not recognizing the new python version, or is missing a pathway. I have a very basic understanding of how these two programs link together, but I've been trying to follow this thread http://forums.arcgis.com/threads/23230-quot-ImportError-No-module-named-arcpy-quot-PYTHON and I seem to have a similar problem. I'm hoping to avoid having to remove all python and GIS programs from my computer and reinstall again...any help would be greatly appreciated. Some other info in case it's helpful: -Only one version of python installed (2.7.6 32bit, C:\Python27) -GIS is here: C:\Program Files (x86)\ArcGIS\Desktop10.2 -Also have these files C:\Program Files (x86)\ArcGIS\Desktop10.2\arcpy C:\Program Files (x86)\ArcGIS\Desktop10.2\bin -Don't have this file C:\Python27\ArgGIS10.2 Apologies if I'm not providing the correct information... Thanks, Heather
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02-27-2014
08:20 PM
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Hi Jason, Thanks for another extremely clear answer. Much appreciated. Cheers, Heather
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06-19-2013
11:07 PM
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Hi Jason, hoping to catch you again. I've gone with the Del2a fill, as you suggested for someone who does not understand the math behind the method. I'm struggling to gain a surface understanding of how the fill applies both interpolation and extrapolation. If a pixel is missing data, is it's value both interpolated and extrapolated and then compared? Or does the fill follow the curve of known data points to value a missing pixel, and it's simply interpolated if it's found value is within the known data range, and extrapolated if it's found value is outside the known data range? Apologies for my basic language. -Heather
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06-17-2013
09:21 PM
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Jason, Thank you so much for taking the time to write such a thorough reply. Your response is unbelievably helpful. Best, Heather
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05-12-2013
08:27 PM
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Hello-- I'm working on a project using monthly 9km resolution ocean color images (of chlorophyl a). Due to clouds, satellite paths, etc, the images have a fair amount of no data pixels. I need to fill in the pixels, but am wary of creating data. A few questions: 1. Is there a general consensus about the maximum size of no data regions that can still be filled reasonably accurately? 2. If I assign the maximum no data region size that can be filled, say, at 25, does this mean that blocks of missing data greater than 25 pixels will not be filled? What about a group of 25 pixels connected diagonally? 3. Does anyone have a suggestion for what fill method to use? I've been playing around with some options in the Marine Geospatial Ecology Tools package, such a Laplacian and Spring, but there are several others such as Del2b, Del2c, and Del4. I've also looked into using a roving window under focal statistics. 4. During the fill process, I'd be interested to create a 2nd raster that details the confidence in filled pixel values. Perhaps this would be best expressed as the number of real value pixels that were used to create an interpolated value. Has anyone done something like this, or have any ideas for how it might be done? Cheers, Heather
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05-08-2013
09:15 PM
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