Python is a free, cross-platform, open-source programming language. It is widely used and supported. To learn more about Python, visit the Python website.
ArcGIS AllSource uses Python 3. Python 3 is a popular programming language that is used in a variety of fields including data analysis, data science, quality assurance, and web and software development. In addition, ArcGIS AllSource includes many third-party Python modules by default.
Learning Python
In addition to the ArcGIS AllSource Python help, you can learn more from the Learn Python in ArcGIS Pro ArcGIS Learn tutorial and the following Esri Press books by Paul A. Zandbergen, regardless of your skill level or experience:
A suitable Python reference book is recommended to augment the ArcPy-focused information included here. There are many books on Python and its uses, with new ones released regularly, so explore what is available. The Python website has full documentation for Python, but it is concise and developer oriented. There is a large online Python community with many online resources that are accessible from the Python home page.
Python tutorials
If you are new to Python, the following external tutorials are recommended:
- The Python Tutorial is available in the Python documentation.
- Python for Non-Programmers provides tutorials for those with limited programming experience.
- The Python Language Reference describes the syntax and semantics of Python.
Python tutorials for programmers
The following external tutorials are for those who have programming experience:
- The Python Tutorial is available in the Python documentation.
- Python for Programmers provides tutorials for those with experience in other programming languages.
Conda
Python is the primary language for automation in ArcGIS AllSource, due in large part to its versatility and extensibility. It is partially due to these qualities that Python is also becoming one of the most widely used programming languages in general. Python has a variety of preexisting packages that can be used in ArcGIS. However, managing which packages are installed on a system can be a complex and time-consuming task, especially when working on multiple projects or trying to share code with others.
Using this versatility, the Python community has created methods to create projects in multiple versions of Python and simplify the process of installing nearly all publicly available Python packages. Conda is a popular and widely used Python package manager.
The functionality of conda is integrated into ArcGIS AllSource through the Package Manager page. The package manager removes many of the challenges faced when writing Python code. It supports installing open-source and third-party libraries that are associated with an individual project, rather than the base Python installation. This simplifies the process of successfully sharing complex Python tools across multiple computers.
Run Python
You can run Python interactively in ArcGIS AllSource using the Python window or ArcGIS Notebooks. The Python window provides a prompt from which short snippets of Python code can be run. ArcGIS Notebooks is based on the Jupyter Notebook architecture and offers an experience in which code, visualizations, and narrative text can be run and stored together in one document.
You can run Python scripts (files with a .py extension) outside of ArcGIS AllSource. The subsections below describe how to run Python scripts from outside the application with the correct ArcGIS AllSource Python 3 conda environment activated.
Start from a command prompt
To start Python from a command prompt, type the following:
"%PROGRAMFILES%\ArcGIS\Pro\bin\Python\Scripts\propy"Note:
All paths shown assume a per-machine (all users) installation of ArcGIS AllSource. If ArcGIS AllSource has been installed for the current user, substitute %LOCALAPPDATA% for %PROGRAMFILES%.
To run a Python script from a command prompt (arguments can be added following the .py extension), type the following:
"C:\Program Files\ArcGIS\Pro\bin\Python\Scripts\propy" myscript.pyStart the ArcGIS AllSource Python 3 conda environment:
"%PROGRAMFILES%\ArcGIS\Pro\bin\Python\Scripts\proenv"Start from a batch file
To run a Python script from a .bat file, use call on propy:
@echo Run my Python script
call "%PROGRAMFILES%\ArcGIS\Pro\bin\Python\Scripts\propy" myscript.py
@echo FinishedRun as a scheduled task
If you are running a Python script as a scheduled task, use C:\PROGRA~1\ArcGIS\Pro\bin\Python\Scripts\propy for the program or script, and include the full path to the Python script in all arguments.
Shortcuts
Use the following shortcuts to access Python:
| Shortcut | Description |
|---|---|
Python Command Prompt | Opens a command prompt window initialized with the current conda environment. To start an interactive Python session, type python. To run a Python script, type python followed by the path of a .py file. |
Python Interactive Terminal | Opens a Python session with the current conda environment. |
Python IDEs
Most modern Python integrated development environments (IDEs) can be used seamlessly with conda by configuring the version of Python that the IDE uses. The primary step involves directing the IDE to use the correct Python.exe file in the ArcGIS AllSource installation. To configure several common IDEs, see Using IDEs in the conda documentation or the documentation for the particular IDE.
You can launch Python IDLE from a conda environment by typing idle.
Migration
If you are migrating Python code written to a version of ArcGIS Desktop (or ArcGIS Server or ArcGIS Engine), see Python migration from 10.x to ArcGIS AllSource. The primary differences are that ArcGIS AllSource uses Python 3 and other ArcGIS products use Python 2, and ArcPy has some differences in the tools it includes. For example, the arcpy.mapping module is replaced by the arcpy.mp module.
Troubleshooting
ArcPy must be run from inside a conda environment, which ArcGIS AllSource uses to manage the installation of Python. To access this environment, open Python from the links in the start menu group or run proenv in a terminal.
If a conda environment is opened in a command window without the necessary administration privileges, a message appears indicating the lack of permissions. Close the command window, reopen it, and run as an administrator.
Authorize Python outside the application
If you run Python scripts that use ArcGIS AllSource functionality outside of the ArcGIS AllSource application—such as a Python IDE—from a command prompt, or running scripts through scheduled tasks, one of the following conditions must be met:
- Sign me in automatically is checked when signing in to ArcGIS AllSource.
- ArcGIS AllSource is currently open.
- ArcGIS AllSource has been authorized to work offline.
- ArcGIS AllSource is configured with a Concurrent Use license and at least one license is available on ArcGIS License Manager.
Note:
If none of the above conditions are met, a RuntimeError: NotInitialized exception appears when importing arcpy or arcgisscripting.