Interpolating rasters into mosaic from point data using LayerTime object in ArcPy?

Question

While trying to run the ArcGIS provided python script to interpolate a bunch of rasters on a time-enabled point feature class file I get the following error:

Runtime error Traceback (most recent call last): File "", line 34, in File "c:\program files (x86)\arcgis\desktop10.2\arcpy\arcpy\management.py", line 6043, in MakeFeatureLayer raise e ExecuteError: ERROR 000840: The value is not a Feature Layer.

My code is this (line 34 is talking about making a feature class, and I cannot for the life of me figure out what it's referring to):

 import arcpy, datetime
# Check out the ArcGIS Spatial Analyst extension for using the IDW interpolation tool
arcpy.CheckOutExtension("spatial")
arcpy.env.workspace = "C:\Users\Chris\Desktop\interpolation\Interpolation.gdb"
# Get the layer time properties
lyr = arcpy.mapping.Layer(r"C:\Users\Chris\Desktop\interpolation\points.lyr")
lyrTime = lyr.time
# Calculate the number of iterations based on the time extent and timestep interval
startTime = lyrTime.startTime
endTime = lyrTime.endTime
timeExtent = endTime - startTime
timeStepInterval = lyrTime.timeStepInterval
iterations = timeExtent.days / timeStepInterval.interval
# Get the time field containing the time values associated
# with the data in the time-enabled layer
startTimeField = str(lyrTime.startTimeField)
# Specify the output mosaic dataset to which the interpolated rasters will be added 
outputMosaicDataset = r"C:\Users\Chris\Desktop\interpolation\Interpolation.gdb\rasta"
i = 0
while i <= iterations:
 # Formulate the time query and increment the time by the timeStepInterval
 currentTime = str(startTime + (i*timeStepInterval))
 timeQuery = "\"" + startTimeField + "\"" + " = date '" + currentTime + "'"
 # Create an in-memory feature layer containing points that are valid at each timestep
 tempFeatureLyr = "tempTimeLayer" + str(i)
 arcpy.MakeFeatureLayer_management(lyr, tempFeatureLyr, timeQuery)
 # Create an interpolated raster surface using the points valid at each timestep
 outRaster = r"C:\Users\Chris\Desktop\interpolation\Interpolation.gdb\output" + str(i)
 print outRaster
 arcpy.gp.Idw_sa(tempFeatureLyr, "avg_hrly", outRaster)
 # Add the newly created raster surface to a Mosaic Dataset
 arcpy.AddRastersToMosaicDataset_management(outputMosaicDataset, "Raster Dataset", outRaster)
 i = i + 1
# Calculate the statistics on the output Mosaic Dataset for
# classifying your data after new rasters are added 
arcpy.CalculateStatistics_management(outputMosaicDataset,"1","1","#")

The error (near top of this post) points to line 34, which reads:

arcpy.MakeFeatureLayer_management(lyr, tempFeatureLyr, timeQuery)

I have checked lyr.isFeatureLayer and it's True, timeQuery returns the next time slice in a proper string format that i have verified in the SQL builder, and tempFeatureLyr = 'tempTimeLayer1'...but it does not create it. As in, I do not see tempTimeLayer1 layer in the Table of Contents, though tempTimeLayer0 IS. So, it's not being created, though its name (tempTimeLayer1) is ready to go...

Here is the site I got the help from, example 3: LayerTime(arcpy.mapping)

• PolyGeo: Your code does not show your lyr variable being set anywhere.
• PolyGeo: I'm confused - there's no error showing in the "python window comments while the tool is running" that you posted. I would try running your code from IDLE and then posting the exact error it throws against the exact code you post.
• geokrowding: i have, it's at the very top. The rest was posted not knowing if it would help others or not; evidently, I'll just remove it.

Answer 1

The error you are showing is coming from c:\program files (x86)\arcgis\desktop10.2\arcpy\arcpy\management.py and it would be easier to take a stab at its cause if we knew the precise line from your script - running it in IDLE is how I usually find that.

It may be that it is simply due to you having:

arcpy.env.workspace = "C:\Users\Chris\Desktop\interpolation\Interpolation.gdb"

instead of:

arcpy.env.workspace = r"C:\Users\Chris\Desktop\interpolation\Interpolation.gdb"

• geokrowding: thanks for the thought, i'll put the r in and let you know. In reference to taking a stab at the arcpy\management.py error, I actually opened up the file and had intentions of going to line 6043 to get more info, but the code is obfuscated, or something, and I couldn't see more than the first 30 lines or so. Standby and I will adjust with the r. What does the r and u do before paths anyway?
• PolyGeo: I would advise strongly against editing anything in c:\program files (x86)\arcgis\desktop10.2\arcpy\arcpy because it could invalidate your install. r stands for raw and says to just read the rest of the string "as-is" without interpreting the backslashes as escape characters. u is to do with Unicode characters.
• geokrowding: noted, thanks. I was more or less wanting to poke around the see where it tripped. I appreciate the explanation on r/u, cheers.
• PolyGeo: The errors from IDLE usually point me straight at where the problem lies.
• geokrowding: So in going to IDLE to see what line or info might help it actually ran! Thanks for the nudge