Latest Contributions by LotharUlferts

that's it Thanks! ... View more

This may help: import arcpy as ap table = <path_to_table> dest_table = <path_for_your_output> field_name ='EXP_CST' day_string = '2018-01-31' # If your string sequence is marked by double quotes, single quotes can be simply used  inside the string. # The two '%' represents any number of signs (including none) before and after the string you're looking for. # Use ap.AddFieldDelimiters to be flexible in shp, mdb, fgdb and others dataformats. sql_expression = "{field} LIKE '%{sub_string}%'".format(field=ap.AddFieldDelimiters(table,                                                                                                                                         field_name),                                                                                            sub_string=day_string) sql_expression #prompt the result ap.analysis.Select(table, dest_table, sql_expression) This code doesn't include a solution for transforming string to date and maybe reverse. ... View more

Because DIR doesnt appear in the winddir function , I removed the parameter in the def-statement. I guess you're working in the python-window, so please try this: arcpy.env.workspace= "A:\\test" # Change to the data source directory tables = arcpy.ListFeatureClasses('*') #all shapes inside the directory #ALTERNATIVE if tables wanted # tables = arcpy.ListFiles('*.dbf') #all dBase-files inside the directory                            len(tables) # just to controll, should be ~50 for table in tables: #loop through all files     #     with arcpy.da.UpdateCursor(table,["DIR","U","V"]) as cursor:         for row in cursor: #loop through all rows             u,v = row[-2:]             row[0] = winddir(u,v) #new DIR-value associated             cursor.updateRow(row) #rewrite the row in the table You can replace line 11&12  by this expression: row[0] = winddir(*row[-2:]) ... View more

Uups, because you calculate only with integer it's better to use int() then float(). ... View more

import math k = (180/math.pi) def winddir(v,u):     v = float(v)     u = float(u)     if v > 0:          result = (180/math.pi)*math.atan(u/v)+180)      elif u < 0 and v < 0:          result = ((180/math.pi)*math.atan(u/v))      elif u > 0 and v < 0:          result = ((180/math.pi)*math.atan(u/v)+360)      elif v == 0 and u > 0:          result = 270      elif v == 0 and u < 0:         result = 90      else: result = -1     return result #-------------------        windir(!V!,!U!) Line 21 belongs to the expression-line, L1- 18  is part of the codeblock So the expression in L21 calls the windir function (L4-18) for every feature in the table with the current values of the fields V and U. Dir is the targetfield for the result of the function. For the function itself it's not nessesary. Line 1&2 will be evaluated only one time at the start of calculation. The following lines will be evaluated as a part of the windir-function every feature/record L4: The function to calculate the wind direction needs only two parameters: The values of the fields U and V. L5&6: You have to make shure, that the variables have the correct datatype. L8,10,12,14&17: The variable is defined by the calculation and at ... L18 at least by the word return the function has the instruction to  "give the value back to the one who calls you up" It's more "pythonical" to do it like Freddie, but for beginners/examples  my contruction is easyer to understand. L17: Every time you  use an if statemant, IMO you have to use else at the end to capture all other oportunities. ... View more

One supplement to my first comment: The algorythm behind wildcard seems to be an legacy from 9.3. Like in these old times upper- and lowercase are unpythonical ignored: You are free to write '*ANalySis' or '*analysis' or whatever simular you want to write , if you are looking for '(analysis)' in fact.  ... View more

The searchstring doesnt end with parenthesis, the result founded do. IMO it's unlogical. ... View more

Hi Joshua, thanks for your comprehensive and penetrative answer! I have to digest your code , but I think it contains all answers i'm looking for. Lothar ... View more

The OMD is my scout in dark nights of program disorientation... ... View more