Writing your own modules

For example, you can create a module called myUtilities by copying a modified version of the function that calculates the distance from a point to the origin into a file called myUtilities.py.

""" myUtilities - a module of mathematical functions"""

import math
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
def distance(x, y):
    """
    Prints distance from origin to (x, y).

    Takes two arguments, x and y. 
    """ 

    # Square the arguments and add them. 

    a = x**2 + y**2

    # Return the square root.

    return math.sqrt(a)

You must import the module to make use of the functions and constants that it contains.

import myUtilities

distance = myUtilities.distance(30, 50)

You can use the __doc__ method to obtain the documentation string from a module. For example,

myUtilities.__doc__
' myUtilities - a module of mathematical functions'

A tool for finding bugs in your modules is provided with Abaqus. The tool is called pychecker. When you import a module, pychecker prints warnings for any problems it finds with the Python source code. For example,

>>> from pychecker import checker
>>> import myUtilities
d:\users\smith\myUtilities.py:3: Imported module (sys) not used
d:\users\smith\myUtilities.py:14: Local variable (a) not used
d:\users\smith\myUtilities.py:18: No global (b) found

For more information about pychecker, see the official Python website (http://www.python.org)

If you import a module during an interactive session using the command line interface and then make changes to the module, Python will not recognize your changes until you reload the module; for example:

import myModule
maxStress = myModule.calculateStress(odb)

# Edit myModule.py and modify the calculateStress method.

reload(myModule)
maxStress = myModule.calculateStress(odb)