topic How to set relative path in notebook in Python Questions

How to set relative path in notebook

JV_ — Wed, 18 Dec 2024 11:45:54 GMT

Hi,

I'm working on a code that I would like to share and, ideally, I want to use relative paths. However, I've tried several approaches and found that it only works when I use the complete path.

Here's a simplified example where I attempt to insert a feature from a geodatabase:

# Path to your feature class in the geodatabase
feature_class_path = feature_path
# Get the current project
project = arcpy.mp.ArcGISProject("CURRENT")

# Get the active map (or specify which map to use)
map_object = project.listMaps()[0]  # Assuming you want the first map

# Add the feature class to the map
map_object.addDataFromPath(feature_class_path)

print(f"Feature class '{feature_class_path}' added to the map.")

When I set feature_class_path using a relative path like this:

feature_class_path = r".\UpdatePoints\UpdatePoints.gdb\Earthquakes_points"

it doesn't work. If I use:

feature_class_path = os.path.join(".", "UpdatePoints", "UpdatePoints.gdb", "Earthquakes_points")

it still doesn't work.

The code only functions correctly when I use the full path:

feature_class_path = r"C:\Users\YourUsername\Documents\UpdatePoints\UpdatePoints.gdb\Earthquakes_points"

Why is that?

Re: How to set relative path in notebook

DanPatterson — Wed, 18 Dec 2024 11:59:13 GMT

p = arcpy.mp.ArcGISProject('CURRENT') #Project information print(f'Project: {p.filePath}')

perhaps, then strip off the filename

Re: How to set relative path in notebook

AlfredBaldenweck — Wed, 18 Dec 2024 14:48:50 GMT

hmmm.

Try something like this:

import os # Get the current project project = arcpy.mp.ArcGISProject("CURRENT") # Change working directory os.chdir(os.path.dirname(project)) # Path to your feature class in the geodatabase # Hard-code in the relative path, then resolve it to absolute # for use in geoprocessing feature_class_path = r".\ex.gdb\feature_path" feature_class_path = os.path.abspath(feature_class_path) # Get the active map (or specify which map to use) map_object = project.listMaps()[0] # Assuming you want the first map # Add the feature class to the map map_object.addDataFromPath(feature_class_path) print(f"Feature class '{feature_class_path}' added to the map.")

Re: How to set relative path in notebook

JV_ — Thu, 19 Dec 2024 11:27:34 GMT

No, didn't work either

Re: How to set relative path in notebook

AlfredBaldenweck — Thu, 19 Dec 2024 17:09:47 GMT

So, two things:

I messed up and fed os.path.dirname() an APRX project instead of a file path
The file has to actually exist.

import os # Get the current project project = arcpy.mp.ArcGISProject("CURRENT") # Change working directory os.chdir(os.path.dirname(project.filePath)) # Path to your feature class in the geodatabase # Hard-code in the relative path, then resolve it to absolute # for use in geoprocessing feature_class_path = r".\Default.gdb\example" feature_class_path = os.path.abspath(feature_class_path) print(feature_class_path) # Get the active map (or specify which map to use) map_object = project.listMaps()[0] # Assuming you want the first map # Add the feature class to the map map_object.addDataFromPath(feature_class_path)

This worked fine for me with "example", but "example2" failed because it doesn't exist.

So you'll want to add an if arcpy.Exists(feature_class_path) in there somewhere.

Re: How to set relative path in notebook

HaydenWelch — Mon, 23 Dec 2024 16:49:19 GMT

I try to avoid using chdir in my scripts usually because it can make debugging a bit difficult.

Just use full paths for everything, but name the segments (e.g. project_directory, working_database, active_dataset, etc.) that way you can see exactly what is being accessed. I usually use pathlib.Path objects so I can use inline operators and avoid messy os.path.join calls.

If you need relative pathing, you can accomplish that using pathlib too.

Here's a code example:

from pathlib import Path import arcpy from arcpy._mp import Map # Get Project prj = arcpy.mp.ArcGISProject("CURRENT") # Set Paths home_folder = Path(prj.homeFolder) database: Path = home_folder / "Data.gdb" feature_class: Path = database / "FeatureClass" # Get Map _map: Map = prj.listMaps("Map Name")[0] # Add Featureclass _map.addDataFromPath(str(feature_class))