Getting Started

Introduction

pyabaqus is a Python package providing type hints for Python scripting of Abaqus, you can use it to write you Python script of Abaqus fluently, even without doing anything in Abaqus. It also provides some simple APIs to execute the Abaqus commands so that you can run your Python script to build the model, submit the job and extract the output data in just one Python script, even without opening the Abaqus/CAE.

Two Python interpreters

Before we go any further, it is necessary for us to understand two Python interpreters.

When we use the Abaqus/CAE graphical user interface (GUI) to create a model and to visualize the results, commands are issued internally by Abaqus/CAE after every operation. These commands reflect the geometry you created along with the options and settings you selected from each dialog box. The GUI generates commands in an object-oriented programming language called Python. The commands issued by the GUI are sent to the Abaqus/CAE kernel. The kernel interprets the commands and uses the options and settings to create an internal representation of our model. The kernel is the brains behind Abaqus/CAE. The GUI is the interface between the user and the kernel.

In a word, Abaqus use Python language to interact with the Abaqus kernel, everything that can be done in Abaqus/CAE, can also be done using Python script. Abaqus has already installed a Python interpreter so that Abaqus/CAE can use it to interact with the Abaqus kernel.

For some reasons, we cannot directly use the Python interpreter inside Abaqus to build an Abaqus model. But fortunately, we can use the commands provided by Abaqus to access it. i.e.

abaqus cae
    [database=database-file]
    [replay=replay-file]
    [recover=journal-file]
    [startup=startup-file]
    [script=script-file]
    [noGUI=noGUI-file]
    [noenvstartup]
    [noSavedOptions]
    [noSavedGuiPrefs]
    [noStartupDialog]
    [custom=script-file]
    [guiTester=GUI-script]
    [guiRecord]
    [guiNoRecord]

Usually, we can use the noGUI-file or script-file to execute our Python script in Abaqus.

Another Python interpreter, is the Python interpreter installed by ourselves, where pyabaqus is installed. pyabaqus provides a bridge to connect our Python script to Abaqus Python interpreter, it provides type hints for Python scripting for Abaqus, enabling us to write a Abaqus Python script quickly.

How does this package work?

pyabaqus is just a package to provide type hints for Abaqus/Python scripting, it is installed outside Abaqus/Python environment, you can use pyabaqus to write your Abaqus/Python scripts, and run the scripts inside Abaqus on your own. However, with the help of Abaqus command, an easier way can be achieved: you can actually run the script using your own Python interpreter without opening Abaqus, which is achieved via the abaqus command like this:

abaqus cae -noGUI script.py

The secret is hided in the saveAs() method:

def saveAs(self, pathName: str):
    abaqus = 'abaqus'
    if 'ABAQUS_BAT_PATH' in os.environ.keys():
        abaqus = os.environ['ABAQUS_BAT_PATH']
    os.system('{} cae -noGUI {}'.format(abaqus, os.path.abspath(sys.argv[0])))

In this package, the saveAs() method is reimplemented, if you call this method in your script (i.e., mdb.saveAs(‘model.cae’)), the Python interpreter (not Abaqus Python interpreter) will use the abaqus command to submit this script to Abaqus, when it is submited to Abaqus, saveAs() will be just a normal method to save the model because pyabaqus is not installed in Abaqus Python interpreter.

In the output script, we might not have to use the saveAs() method, then another similar method openOdb() is also reimplemented:

def openOdb(self, name: str, *args, **kwargs):
    abaqus = 'abaqus'
    if 'ABAQUS_BAT_PATH' in os.environ.keys():
        abaqus = os.environ['ABAQUS_BAT_PATH']
    os.system('{} cae database={} script={}'.format(abaqus, os.path.abspath(name), os.path.abspath(sys.argv[0])))

Therefore, if you want to run your Python script in Abaqus Python environment, please make sure to use these methods.