Installing PIP for Python

If you’re on a Mac running macOS Sierra, you can install PIP to add packages. PIP stands for either of the following:

  • PIP installs Packages
  • PIP installs Python

You use the following to install the PIP utility:

sudo easy_install pip

It should return the following:

Searching for pip
Reading https://pypi.python.org/simple/pip/
Best match: pip 9.0.1
Downloading https://pypi.python.org/packages/11/b6/abcb525026a4be042b486df43905d6893fb04f05aac21c32c638e939e447/pip-9.0.1.tar.gz#md5=35f01da33009719497f01a4ba69d63c9
Processing pip-9.0.1.tar.gz
Writing /tmp/easy_install-ryxjDg/pip-9.0. (more...)

Python variable not defined

While working with a programming example for my students, I ran into an interesting run-time error when I changed their approach to importing Python’s random module. Here’s the raised error message:

Traceback (most recent call last):
  File "windowBouncingBalls.py", line 84, in 
    speed = [choice([-2,2]), choice([-2,2])]
NameError: name 'choice' is not defined

You raise the missing choice identifier when two things occur. The first thing requires you to use a standard import statement, like the (more...)

Install PyGame on Fedora

The PyGame library is a wonderful tool for building games with Python. It lets you accomplish a great deal by simply managing events. You need to understand how to use Python functions, modules, and events to build games with this Python library.

You can download and install the PyGame library with the yum utility like this:

yum install -y pygame

It should generate the following list when you install it as the root user:

Loaded  (more...)

Install EasyGUI on Fedora

The EasyGUI library is a nice tool for developing GUI applications. It doesn’t require you to know event-driven programming to write basic GUI applications because it’s based on Python functions.

You can download and install the EasyGUI library with yum utility like this:

yum install -y python-easygui

It should generate the following list:

Loaded plugins: langpacks, refresh-packagekit
mysql-connectors-community                                  | 2.5 kB  00:00     
mysql-tools-community                                       | 2.5 kB  00:00     
mysql56-community                                           | 2.5 kB  00:00     
 (more...)

Reset Oracle Password

This blog entry shows you how to reset the system password for an Oracle Database. It uses a Linux image running Oracle Database 11g Express Edition. It assumes the student user is the sudoer user.

After you sign on to the student user account, you open a Terminal session and you should see the following:

[student@localhost python]$ 

The oracle user account should be configured to prevent a login. So, you should use the su (more...)

Oracle Diagnostic Queries

It’s always a challenge when you want to build your own Oracle SQL Tools. I was asked how you could synchronize multiple cursors into a single source. The answer is quite simple, you write an Oracle object type to represent a record structure, an Oracle list of the record structure, and a stored function to return the list of the record structure.

For this example, you create the following table_struct object type and a table_list (more...)

Basic Python Object

One of my students wanted a quick example of a Python object with getters and setters. So, I wrote a little example that I’ll share.

You define this file in a physical directory that is in your $PYTHONPATH, like this:

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class Coordinate:
  def __init__ (self, x, y):
    self.x = x
     (more...)

Create a Python Module

Sometime formal programming documentation is less than clear. At least, it’s less than clear until you’ve written your first solution. The Modules section of the Python language is one of those that takes a few moments to digest.

Chapters 22 and 23 in Learning Python gives some additional details but not a clear step-by-step approach to implementing Python modules. This post is designed to present the steps to write, import, and call a Python module. (more...)

Python for loops

It’s always interesting to explain a new programming language to students. Python does presents some challenges to that learning process. I think for loop can be a bit of a challenge until you understand them. Many students are most familiar with the traditional for loop like Java:

for (i = 0; i < 5; i++) { ... }

Python supports three types of for loops – a range for loop, a (more...)

Install cx_Oracle for Python

This shows you how to install the cx_Oracle library for Python 2.7 on Fedora Linux. If Fedora has it on the server you can download it with the following yum command:

yum install -y cx_Oracle-5.2.1-11g-py27-1.x86_64.rpm

Currently, you’ll get the following failure because it’s not available in the Fedora repository:

Loaded plugins: langpacks, refresh-packagekit
mysql-connectors-community                                      | 2.5 kB  00:00:00     
mysql-tools-community                                           | 2.5 kB  00:00:00     
mysql56-community                                               | 2.5  (more...)