Hi Guys,
I'm a beginner to python scripting in GIS. I ‘m trying to make a loop for field “value” and “count” of a raster data. The logic behind the code is:
-1st calculate the total number of counts in the original raster
- use the " 1st value" from value field of the raster attribute of original raster to extract a new raster using raster calculator
-calculate the total number of counts in the new raster
-If the total counts of new raster < 0.25*(total counts of original raster)
-Then got the threshold value(which was used to calculate new raster from the original raster)
-Else, use the next value from the old raster attribute to calculate new raster and the total “count” of new raster until the total counts of new raster is < 0.25* (total counts of original raster).
I am providing the code below.However, I am getting "invalid syntax error" at the end of the for loop in the code below where it says "next row". I would appreciate any comment/suggestion.
Thanks!
Code:
import arcpy
from arcpy import env
from arcpy.sa import *
#To overwrite output
arcpy.env.overwriteOutput = True
#Set environment settings
env.workspace = "C:/Subhasis/Test/Neshanic_Python"
# set local variable
inraster ="01367620-r-r"
# read attribute table of raster
rows = arcpy.SearchCursor(inraster,"","","Count","")
# sum of counts in raster
s1=[]
for row in rows:
s1.append(row.getValue("Count"))
A= sum(s1)
#checkout ArcGIS spatial analyst extension license
arcpy.CheckOutExtension("Spatial")
# read attribute table of raster
rows = arcpy.SearchCursor(inraster,"","","value","")
for row in rows:
inSQLClause = "VALUE = row"
attExtract = ExtractByAttributes(inraster, inSQLClause)
attExtract.save("C:/Subhasis/Test/Neshanic_Python/STI-TH")
inraster="STI-TH"
rows = arcpy.SearchCursor(inraster,"","","Count","")
s2=[]
for row in rows:
s2.append(row.getValue("Count"))
B=sum(s2)
if B<=.25*A:
print 'got the Threshold point for STI row'
else:
print'need to use different STI'
next row
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