Getting Going with Python on Mac OS X
The aim of this web page is to help you get started with Python on Mac OS X. We will explain what a package management tool is, how to download
conda package management tool via the Anaconda installer, and guide you on the OS X Terminal application so that you can use
conda from the command line. Finally, we will wrap up by installing one library with
What Is a Package Management Tool?
A package management tool is a software application that helps you manage software libraries that enable you to get your work done. These software libraries may relate to plotting for scientific publication or accessing certain kinds of data, for example.
When you start using Python, you will want use software libraries that are not part of the standard Python installation. For example, you may wish to use the Unidata metpy library for meteorological data and visualization. Anaconda from Continuum Analytics will help you install
conda Package Management Tool
conda package management tool is part of the Anaconda software package. Install
conda by navigating to the Anaconda download page. Scroll down to the “Anaconda for OS X” portion of the web page.
Download the Python 3.5 version by clicking on the “Mac OS X 64 bit Graphical Installer” link. It is a big download, so it is best to be on fast network. Open the installer file you just downloaded. It should be named something like
This action will guide you through the conda installation on your Mac. The second “Read Me” step is important, as the installation will make some modifications that the OS X Terminal application can make use of. We cover the OS X Terminal next.
OS X Terminal Application
The OS X Terminal is a software program that gives you the ability to give text based instructions to your computer. As you make progress in geoscientific programming, you will probably use the Terminal a lot, so it will benefit you to become familiar with it.
For this exercise we will open up the Terminal by going to the OS X Finder and navigating to the Application, Utilities folder. There you will find the Terminal application which you can double click on to launch.
In the Terminal application, you will see a character such as
$ symbol known as the command line. The command line is where you give text instructions to your computer.
Let’s make sure conda is installed by entering this instruction on the command line:
# packages in environment at /Users/chastang/anaconda: # alabaster 0.7.7 py35_0 anaconda 4.0.0 np110py35_0 anaconda-client 1.4.0 py35_0 ... numexpr 2.5 np110py35_0 numpy 1.10.4 py35_0 odo 0.4.2 py35_0 ... yaml 0.1.6 0 zeromq 4.1.3 0 zlib 1.2.8 0
which will list linked packages in a conda environment. You’ll notice libraries such as the scientific computing library numpy that you will probably be making use of.
If You Have Problems with
conda list worked without trouble, skip this subsection. If that last
conda list command gave you an error, it is possible that you are running the wrong flavor of the OS X Terminal (or more precisely the wrong Unix shell). Ensure you are running the
bash shell by going to Terminal, Preferences… menu, and verifying that
/bin/bash is selected. If you change it, please quit, and restart the Terminal application.
Getting Our Feet Wet by Installing Metpy with
We first have to give
conda an instruction on where to find
metpy on the
conda config --add channels conda-forge
We can now install
conda install metpy
Let’s verify we installed
metpy with the following command:
should yield amongst other libraries:
# packages in environment at /Users/chastang/anaconda: # ... metpy 0.3.0 py35_1 conda-forge ...
You have just learned how to:
- Installed the
In future installments of the Unidata Online Python training, we will be using
conda to install various libraries.