ERROR 999998: Unexpected Error raster algebra
I have been playing around with the original code posted above tonight. I try to run it from PythonWin and from the Python window within ArcGIS. It worked once or twice using PythonWin and most of the times from within ArcGIS, but for the first time I got the same error message when running it within ArcGIS.
I was able to compile a different code to try to accomplish the same thing than the original one. You can find the code below. It works most of the time from PythonWin, but it does not yield the same results than the original code (see image below). I ran both versions of the code from within ArcGIS and compare the results (just min and max showing on the figure below) with one raster calculated step by step using the raster calculator in ArcGIS. Could someone help me to understand why the two codes yield different results?
Thanks.
import arcpy, string, os, errno
from arcpy import env
from arcpy.sa import*
from datetime import datetime
arcpy.CheckOutExtension("spatial")
arcpy.env.overwriteOutput = True
start_time = datetime.now()
imagery = r'E:\UAV2017\PythonField8ExGr\Field8_90ft_08012017.tif'
#Get path information to create Results folder, where NDVI and NDRE will be saved
path = os.path.dirname(imagery)
print path
base1 = os.path.basename(imagery)
base = os.path.splitext(base1)[0]
print base
#Saving name for Excess Green mosaic - using basename from the original imagery
exgr_filename = base + "_ExGr.tif"
Nred = "Nred.tif"
Nblue = "Nblue.tif"
Ngreen = "Ngreen.tif"
#Set workspace to multiband raster, then list rasters to get band names
arcpy.env.workspace = imagery
bands = [Raster(os.path.join(imagery, b)) for b in arcpy.ListRasters()]
print bands
Red = imagery + "\Band_1"
print Red
Green = imagery + "\Band_2"
print Green
Blue = imagery + "\Band_3"
print Blue
red_out = "Red.tif"
green_out = "Green.tif"
blue_out = "Blue.tif"
arcpy.CopyRaster_management(Red, red_out)
arcpy.CopyRaster_management(Green, green_out)
arcpy.CopyRaster_management(Blue, blue_out)
print "Rasters successfully copied"
#Set workspace to the location were the results will be saved
arcpy.env.workspace = path
nred_num = arcpy.sa.Float(Raster(red_out))
Denom = arcpy.sa.Float(Raster(red_out) + Raster(green_out)+ Raster(blue_out))
Nred_eq = arcpy.sa.Divide(nred_num, Denom)
Nred_eq.save(Nred)
print "Nred saved"
ngreen_num = arcpy.sa.Float(Raster(green_out))
Ngreen_eq = arcpy.sa.Divide(ngreen_num, Denom)
Ngreen_eq.save(Ngreen)
print "Ngreen saved"
nblue_num = arcpy.sa.Float(Raster(blue_out))
Nblue_eq = arcpy.sa.Divide(nblue_num, Denom)
Nblue_eq.save(Nblue)
print "NBlue saved"
Ngreen_x2 = arcpy.sa.Times(Ngreen, 2)
Nred_minus_Nblue = arcpy.sa.Minus(Nred, Nblue)
ExGr_eq = arcpy.sa.Minus(Ngreen_x2, Nred_minus_Nblue)
ExGr_eq.save(exgr_filename)
print "Excess Green calculation successful"
#Build pyramids and calculate statistics for each raster in env.worspace folder
arcpy.BuildPyramids_management(exgr_filename)
arcpy.BuildPyramids_management(exgr_filename)
print "Pyramids and Statistics successful"
end_time = datetime.now()
print('Duration: {}'.format(end_time - start_time))
