In this programming terms video, we will be going over the concept of DRY (Don’t Repeat Yourself). This is a term you will hear a lot if you are just getting started in Computer Science or if you’ve recently started a new programming job. Let’s take a look as to what it means to keep your code “DRY”.
A common question that pops up when dealing with python is: What is the difference between __str__() and __repr__()? It may not be obvious right off the bat, so let’s take an in-depth look at this.
If you navigate from your terminal frequently, you have most likely run into the scenario where you are within a project directory and want to open a file or folder from that project. It is a pain to open up Finder, navigate to the project, and open the file or directory that way. Being able to open these projects and files from the terminal is much more convenient and saves a lot of time. In this video we’ll look at how we can do just that:
The line that links the “subl” command to /usr/local/bin/ is as follows:
ln -s /Applications/Sublime\ Text.app/Contents/SharedSupport/bin/subl /usr/local/bin/sublIn this article, I wanted to talk about volunteering and different ways for Web Developers, Designers, Programmers, and Software Engineers to give back to their community using their skill-set.
There’s a great line in the book “Tuesdays with Morrie” when the main character was talking about giving back to your community. He talks about not giving back with money, but with your skill-set. Here’s the line from that book:
I don’t mean money. I mean your time… It’s not so hard. There’s a senior center that opened near here. Dozens of elderly people come there every day. If you’re a young man or young woman and you have a skill, you are asked to come and teach it. Say you know computers. You come there and teach them computers. You are very welcome there. And they are very grateful. This is how you start to get respect, by offering something that you have.
I couldn’t agree with this more. Sharing a skill you have not only helps others, but it will help you hone your own skills as well.
This got me thinking, what are different ways in which our tech community can volunteer their skills, give back, and have a positive impact on the world?
In a previous video, we learned how to use DiffMerge as a git difftool and git mergetool. As I was creating that video, I noticed a bug in the program that crashed DiffMerge when attempting to change the font-size. This bug has not yet been fixed by DiffMerge; however, there is a workaround.
All we need to do in open the preferences from the terminal and change the font-size manually.
In this video, we will learn how to setup a git difftool and a git mergetool. These tools provide a nice GUI interface for viewing and modifying diffs and merges.
The tool we will be using in this tutorial is called DiffMerge:
https://sourcegear.com/diffmerge/
If you struggle reading or comparing diffs and merges within your terminal, then a good GUI tool can definitely make your life easier.
In this video, we will take a look at the git stash command. Git stash is extremely useful when you have some changes that you want to save but aren’t ready to make a commit.
There are many different scenarios where knowing how to use stash properly will make your life with git much easier.
In this video, we will take an in-depth look at Python’s package management system, pip. We’ll walk through how to install, uninstall, list, and upgrade packages. We will also dive into how we can output our dependencies and install a list of dependencies.
An in-depth knowledge of pip can be a great addition to your Python tool-belt.
Here is a look at some of the code used in this tutorial:
Install a package
pip install <package_name>Uninstall a package
pip uninstall <package_name>Output installed packages to a requirements file.
pip freeze > requirements.txtInstall all packages from a requirements file
pip install -r <name_of_requirements_file>List installed packages
pip listList installed packages that need updated
pip list --outdatedUpgrade a package
pip install -U <package_name>Upgrade all packages (source)
pip freeze --local | grep -v '^\-e' | cut -d = -f 1 | xargs -n1 pip install -UIn this video, we will be looking at virtualenv and why you should be using virtual environments in Python. Virtual Environments in Python allow us to keep project-specific dependencies in a separate place than our global site-packages. This is extremely useful when you have different versions of packages for different projects.
Here’s a brief walkthrough of some of the code from the video:
Install virtualenv
pip install virtualenvCreate a location for your environments (Optional)
mkdir ~/Environments
cd ~/EnvironmentsCreate a new virtual environment (called venv for this example)
virtualenv venvActivate your new virtual environment
source venv/bin/activateAt this point you can work from inside of your new virtual environment and know that you are keeping your project-specific packages and dependencies separate.
When you are finished, you can deactivate your virtual environment
deactivateIf you no longer need your environment and would like to delete it, you can just remove the directory
rm -rf venvOne problem I run into frequently is needing to resize multiple images at once. To do this manually would take way too much time, especially if you have a lot of images.
Luckily, there are several good tools out the to automate this process for us. In this video we will be resizing multiple images using the Mac Terminal and the built-in “sips” command.
If you are someone who is more comfortable using an application rather than the terminal, I also have a video on resizing multiple images using Google’s Picasa. You can find that video here. With that said, in this video we will be focusing on the Mac Terminal. Let’s get started: