Latest Contributions by XanderBakker

True! The with statement does not work for the old cursors, but the list comprehension can be used to determine the min and max... ... View more

Haven't tested it, but this might work in 10.0 SP5: def normalizeField(in_table, in_field, out_field):     lst = [r.getValue(in_field) for r in arcpy.SearchCursor(in_table)]     minimum = min(lst)     maximum = max(lst)     with arcpy.UpdateCursor(in_table) as cur:         for row in cur:             row.setValue(out_field, (float(row.getValue(in_field)) - minimum)/(maximum - minimum))             cur.updateRow(row)         row.setValue ... View more

The data access module (da) was introduced at 10.1... ... View more

You are absolutely right. Memory considerations should be taken into account. ... View more

Nice example Joshua Bixby, but maybe to make it a little shorter you can determine the min and max as follows: def normalizeField(in_table, in_field, out_field):     lst = [r[0] for r in arcpy.da.SearchCursor(in_table, (in_field))]     minimum = min(lst)     maximum = max(lst)     # ect Not sure how this affects performance though. Kind regards, Xander ... View more

Hi Curtis, thanks for the additions! ... View more

Hi Manny, My explanation was a little short, sorry for that... and creating these type of "one-liners" doesn't allow for easy interpretation. Let's break it down into pieces: # let's say we have a list with duplicate values list1 = [1, 3, 5, 7, 3, 2, 5, 6, 8, 7, 5, 4, 3, 2, 6, 2] # the set() is used to convert it to a set of unique values set1 = set(list1) print set1 # returns: set([1, 2, 3, 4, 5, 6, 7, 8]) # if you want to convert it to a list again (to loop over it) list2 = list(set1) print list2 # returns [1, 2, 3, 4, 5, 6, 7, 8] A set is very powerful to get a unique list of values and combining sets allows you to obtain values that are in one list but not in the other and info like this. More on this in my post: Some Python Snippets (scroll down to comparing lists) To create the list some list comprehensions are used (check out this document I posted: Using Python List Comprehensions ). Let's break down the code: unique_list = list(set("{0}_{1}".format(r[0], r[1]) for r in arcpy.da.SearchCursor(FC_or_TBL, (fld_name1, fld_name2, fld_search), where))) The set() and list() at the beginning of the line have been explained above. Within the brackets of the set() command a lot is going on. Let's not start from left to right, but with the SearchCursor. It takes a table or featureclass, a tuple (or list) of field names and in this case a where clause. This is pretty standard and I don't think needs much explanation. Normally when you use a search cursor you obtain a cursor object which you use to loop through each row (or feature) in the cursor. Next you probably access the fields in each row and do something with it like this: with arcpy.da.SearchCursor(FC_or_TBL, (fld_name1, fld_name2, fld_search), where) as curs:     for row in curs:         val_fld1 = row[0]         # etc In case of the list comprehension this is done on one line. It retrieves each row "r" in the SeachCursor and returns this: "{0}_{1}".format(r[0], r[1]) string.format() allows you to create a string and pass in variables. It is a pretty need way to combine values and string in a certain format r[0] refers to the value of fld_name1 r[1] refers to the value of fld_name2 {0} refers to the first parameter specified in the format command {1} refers to the second parameter specified in the format command ... so it the value for fld_name1 is "abc" and the value in fld_name2 would be 1, this would result in the string "abc_1". I used something similar for creating the where clause: where = "{0} = '{1}'".format(arcpy.AddFieldDelimiters(FC_or_TBL, fld_search), search_value) It starts with a string "{0} = '{1}'". The {0} is replaced with the first argument of the format function: arcpy.AddFieldDelimiters(FC_or_TBL, fld_search) This will put quotes or brackets or nothing around the field name based on the type of workspace (that can be useful if you don't know if your input is a shapefiles, personal, file or enterprise geodatabase... The {1} is replace with the value in the variable search_value. Please note that this where clause will fail if your field is not of type TEXT (string). It is possible to extend this functionality and detect the columns type, but for simplicity reasons (read I was to lazy) I did not do that. If you have any other doubt, please let me know... Kind regards, Xander ... View more

You're welcome! ... View more

There is a Point Density (in the Spatial Analyst Toolbox) that might work for you. Kind regards, Xander ... View more

Observe code sample below. Once again I haven't tested the code, so be careful. Changes in syntax can be found on lines 16, 18-20 + 35 and 37 def main():     global arcpy     import arcpy, os     # fixed settings     fldBLOB = 'DATA'     fldAttName = 'ATT_NAME'     fldRelOID = 'REL_OBJECTID'     # your settings (edit these)     fc = r"C:\Project\_LearnPython\Attachments\test.gdb\Meldingen"     tbl = r"C:\Project\_LearnPython\Attachments\test.gdb\Meldingen__ATTACH"     outFolder = r"C:\Project\_LearnPython\Attachments"     fldRelatedInfo = 'SomeFieldInFeatureClass' # should be valid column in FC     with arcpy.SearchCursor(tbl) as cursor:         for row in cursor:             binaryRep = row.getValue(fldBLOB)             fileName = row.getValue(fldAttName)             relOID = row.getValue(fldRelOID)             # access related information             myRelatedInfo = QueryRelatedData(fc, fldRelatedInfo, relOID)             # do something with the related info             # save attachment to disk             open(outFolder + os.sep + fileName, 'wb').write(binaryRep.tobytes())             del row             del binaryRep             del fileName def QueryRelatedData(fc, fldRelatedInfo, relOID):     fldOID = 'OBJECTID'     expression = arcpy.AddFieldDelimiters(fc, fldOID) + " = {0}".format(relOID)     with arcpy.SearchCursor(fc, where_clause=expression) as cursor:         for row in cursor:             return row.getValue(fldRelatedInfo)             break         del row if __name__ == '__main__':     main() ... View more

If you are interested in using some python you could use something like this: import arcpy from arcpy.sa import * dem = "C:/examples/data/dem" # reference to your DEM outname = "C:/examples/data/result" # output raster to be created dem_ras = arcpy.Raster(dem) # create a raster object dem_min = dem_ras.minimum # get minimum of dem outras = Con(dem_ras == dem_min, dem_ras) outras.save(outname) Con http://resources.arcgis.com/en/help/main/10.2/index.html#//009z00000005000000 Raster http://resources.arcgis.com/en/help/main/10.2/index.html#//018z00000051000000 ... View more

The help mentions some requirements (ArcGIS Help 10.1 ) but I suppose you have already checked those. The page also shows some examples in which the sub type field is explicitly set. What happens if you do this? ... View more