I have exported an ArcGIS Desktop 10.7 table into a dbf file.
Now I want to do some GIS calculation in standalone Python.
Therefore I have started a PyCharm project referencing the ArcGIS Python interpreter and hence am able to import arcpy into my main.py.
Problem is: I don't want to pip install other modules, but I don't know how to correctly read the dbf table with arcpy.
#encoding=utf-8 import arcpy path=r"D:\test.dbf" sc=arcpy.SearchCursor(path) # Does not work: IOError exception str() failed tv=arcpy.mapping.TableView(path) # Does not work either: StandaloneObject invalid data source or table
The dbf file is correct, it can be read into ArcGIS.
Can someone please give me an idea, how to read the file standalone with arcpy?
path=r"D:\test.dbf"
Is in the root directory, try putting it into a folder
path=r"D:\TestData\test.dbf"
Also, arcpy.da cursors
SearchCursor—ArcGIS Pro | Documentation
And you need to specify the fields to use (field_names) they are not optional. you only specified the file, and not the fields, so it will fail
SearchCursor (in_table, field_names, {where_clause}, {spatial_reference}, {explode_to_points}, {sql_clause}, {datum_transformation})
Using Pandas
Python from ArcMap comes with some modules. You can load the data into a pandas.DataFrame and work with this format. Pandas is well-documented and there is a lot of already asked question about it all over the web. It's also super easy to do groupby or table manipulations.
import pandas as pd import arcpy def read_arcpy_table(self, table, fields='*', null_value=None): """ Transform a table from ArcMap into a pandas.DataFrame object table : Path the table fields : Fields to load - '*' loads all fields null_value : choose a value to replace null values """ fields_type = {f.name: f.type for f in arcpy.ListFields(table)} if fields == '*': fields = fields_type.keys() fields = [f.name for f in arcpy.ListFields(table) if f.name in fields] fields = [f for f in fields if f in fields_type and fields_type[f] != 'Geometry'] # Remove Geometry field if FeatureClass to avoid bug # Transform in pd.Dataframe np_array = arcpy.da.FeatureClassToNumPyArray(in_table=table, field_names=fields, skip_nulls=False, null_value=null_value) df = self.DataFrame(np_array) return df # Add the function into the loaded pandas module pd.read_arcpy_table = types.MethodType(read_arcpy_table, pd) df = pd.read_arcpy_table(table='path_to_your_table') # Do whatever calculations need to be done
Using CURSOR
You can also use arcpy cursors and dict for simple calculation.
There are simple example on this page on how to use correctly cursors : https://desktop.arcgis.com/fr/arcmap/10.3/analyze/arcpy-data-access/searchcursor-class.html