The Python SpeedSheet: It is an interactive cheat sheet that brings the answer to you. It is a really simple idea but it worked so well that it has become an indispensable tool for me any time I'm coding. Type in what you are looking for in the search bar and the speed sheet will display the answer.

• Install Python 3 Mac Catalina
• Install Python Mac Catalina Download
• Install Python Mac Catalina Update
• Install Python Mac Catalina Operating System
• Install Python 2.7 Mac Catalina

1. The older Python language, version 2.7, is being deprecated in macOS 10.15 Catalina and won't be included in macOS 10.16. The same goes for other UNIX scripting languages.
2. Install Python With Numpy Scipy Matplotlib On Macos Catalina, 1. Download attention-grabbing mp3 or Research tunes by title, artist, genre or album what you want,The result will demonstrate on research display screen selection If you like to stream new music out of your cellular phone or tablet, Audiomack operates this way, too, through the the Android application and the application for iOS.

Posted on October 4, 2016 by Paul

Updated 15 June 2021

In this article, I will show you how to install Python with NumPy, SciPy and Matplotlib on macOS Big Sur.

I assume you are on an Intel based Mac. If you have an arm64 Mac, also called Apple Silicon, please check my other article.

MacOS Big Sur comes by default with Python 2.7 which, at this point, receives only bug fixes and is EOL since 2020. Python 3 is the future and it is supported by all major Python libraries. In this tutorial, we’ll use Python 3.9 which is the latest stable release of Python at the time of this writing.

Start by installing the Command Line Tools for macOS. Please note, that you will need the Command Line Tools even if you’ve already installed Xcode. Open a Terminal and write:

Once the Command Line Tools are installed, we can install Python.

As a side note, after you install the Command Line Tools, you will also get a slightly older Python 3 version (3.8). In this article, we are going to use the latest stable version of Python which, at the time of this writing is 3.9.

Go to https://www.python.org/ and download Python. The official installer of Python is a pkg file that will start a GUI installer which will guide you through the installation.

You can have multiple Python 3 versions installed on your macOS machine. If this is the case, you can select which version you want to use by specifying the version number, e.g.:

or:

After the above, you can invoke Python 3.9 using the python3.9 command. python3 will also invoke the latest installer version of Python 3. This is what I see if I run python3.9 on my machine:

Next, let’s follow best practices and create a new Python environment, named work (feel free to use a different name), in which we can install NumPy, SciPy and Matplotlib:

At this point, your prompt should indicate that you are using the work environment. You can read more about Python environments in the documentation.

Once an environment is activated, all the install commands will apply only to the current environment. By default, if you close your Terminal, the environment is deactivated. If you want to be able to use it, use the source work/bin/activate command.

We can install NumPy, SciPy and Matplotlib with:

As a side note, when you are in an active environment you can use the python command to invoke the Python interpreter, no need to use the version number.

Fire up Python, import scipy and print the version of the installed library. This is what I see on my machine:

Let’s try something a bit more interesting now, let’s plot a simple function with Matplotlib. First, we’ll import NumPy and Matplotlib with:

Next, we can define some points on the (0, 1) interval with:

Now, let’s plot a parabola defined on the above interval:

You should see something like this:

As you’ve probably noticed, plt.show() is a blocking command. You won’t be able to use the interpreter until you close Figure 1.

There is also an interactive mode in which you can plot functions. Close Figure 1 and write:

This is what you should see:

At any point you can disable the interactive plot mode with:

after which you will need to use the plt.show() function in order to actually see the result of the plt.plot function.

If you want to learn more about Python and Matplotlib, I recommend reading Python Crash Course by Eric Matthes. The book is intended for beginners, but has a nice Data Visualization intro to Matplotlib chapter:

Another good Python book, for more advanced users, which also uses Matplotlib for some of the book projects is Python Playground by Mahesh Venkitachalam:

Posted on October 21, 2019 by Paul

Install Python 3 Mac Catalina

Updated 11 February 2020

In this article, I will show you how to install OpenCV 4 with Python 3 on macOS Catalina.

There is also a video version of this tutorial:

MacOS comes by default with Python 2.7 which, at this point, receives only bug fixes and will be EOL by 2020. Python 3.x is the future and it is supported by all major Python libraries. In this tutorial, we’ll use the Python 3.8.

Start by installing the Command Line Tools for macOS. Please note, that you will need the Command Line Tools even if you’ve already installed Xcode. Open a Terminal and write:

Once the Command Line Tools are installed, we can install Python.

The official installer of Python is a pkg file that will start a GUI installer which will guide you through the installation. You can also check the video version of this tutorial if you want to see how I did it.

As a side note, you can have multiple Python 3 versions installed on your macOS machine. If this is the case, you can select which version you want to use by specifying the version number, e.g.:

or:

After the above, you can invoke Python 3.8 using the python3.8 command. python3 will also invoke the latest installer version of Python 3. This is what I see if I run python3.8 on my machine:

Next, let’s follow best practices and create a new Python environment in which we can install NumPy and OpenCV:

At this point, your prompt should indicate that you are using the work environment. You can read more about Python environments in the documentation.

Once an environment is activated, all the install commands will apply only to the current environment. By default, if you close your Terminal, the environment is deactivated. If you want to be able to use it, use the source work/bin/activate command.

We can install NumPy and OpenCV with:

Please note that the above will install the slightly older OpenCV 4.1, latest binary version doesn’t seem to work on macOS Catalina!

As a side note, when you are in a new environment you can use python to invoke the Python interpreter, no need to use the version number.

At this point, you should have OpenCV 4 and Python installed on your Mac. We can write a small test program that will print the OpenCV version, load an image from the disk, convert the image to gray and show the result. Start by downloading the next image:

Save it as clouds.jpg. In the same folder where you’ve saved the above image, create a new file demo.py and write the next code:

Install Python Mac Catalina Download

Run the code with:

Install Python Mac Catalina Update

(You can close the two windows by pressing ESC!)

You should see something like in the next figure. By default, the last image (the gray one) will be over the first one. You need to move the window in order to see both images:

Install Python Mac Catalina Operating System

If you want to learn more about OpenCV and Python I would recommend reading OpenCV with Python Blueprints by M. Beyeler:

or, OpenCV with Python By Example by G. Garrido and P. Joshi:

Install Python 2.7 Mac Catalina