python 3.5 to 3.6

https://www.digitalocean.com/community/tutorials/how-to-install-the-anaconda-python-distribution-on-ubuntu-16-04

This quick tutorial is going to show you how to install the latest Python 3.6.1 in Ubuntu 16.04 LTS via PPA.

Ubuntu 16.04 comes with both Python 2.7 and Python 3.5 by default. You can install Python 3.6 along with them via a third-party PPA by doing following steps:

1. Open terminal via Ctrl+Alt+T or searching for “Terminal” from app launcher. When it opens, run command to add the PPA:

sudo add-apt-repository ppa:jonathonf/python-3.6

Type in your password (no visual feedback due to security reason) when it asks and hit Enter.

2. Then check updates and install Python 3.6 via commands:

sudo apt-get update sudo apt-get install python3.6

Now you have three Python versions, use python command for version 2.7, python3 for version 3.5, and/or python3.6 for version 3.6.1.

3. To make python3 use the new installed python 3.6 instead of the default 3.5 release, run following 2 commands:

sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.5 1 sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.6 2

Finally switch between the two python versions for python3 via command:

sudo update-alternatives --config python3

After selecting version 3.6:

python3 -V

UPDATE: due to this bug, gnome-terminal won’t launch after step 3, a workaround is running following commands to recreate the symlink:

sudo rm /usr/bin/python3 sudo ln -s python3.5 /usr/bin/python3

Prerequisites

Before you begin with this guide, you should have a non-root user with sudo privileges set up on your server. You can learn how to do this by completing our Ubuntu 16.04 initial server setup guide.

Installing Anaconda

The best way to install Anaconda is to download the latest Anaconda installer bash script, verify it, and then run it.

Find the latest version of Anaconda for Python 3 at the Anaconda Downloads page. At the time of writing, the latest version is 5.0.1, but you should use a later stable version if it is available.

Next, change to the /tmp directory on your server. This is a good directory to download ephemeral items, like the Anaconda bash script, which we won't need after running it.

• • cd /tmp

Use curl to download the link that you copied from the Anaconda website:

• • curl -O https://repo.continuum.io/archive/Anaconda3-5.0.1-Linux-x86_64.sh

We can now verify the data integrity of the installer with cryptographic hash verification through the SHA-256 checksum. We’ll use the sha256sum command along with the filename of the script:

• • sha256sum Anaconda3-5.0.1-Linux-x86_64.sh

You’ll receive output that looks similar to this:

Output

55e4db1919f49c92d5abbf27a4be5986ae157f074bf9f8238963cd4582a4068a Anaconda3-5.0.1-Linux-x86_64.sh

You should check the output against the hashes available at the Anaconda with Python 3 on 64-bit Linux page for your appropriate Anaconda version. As long as your output matches the hash displayed in the sha2561 row then you’re good to go.

Now we can run the script:

• • bash Anaconda3-5.0.1-Linux-x86_64.sh

You’ll receive the following output:

Output

Welcome to Anaconda3 5.0.1 (by Continuum Analytics, Inc.) In order to continue the installation process, please review the license agreement. Please, press ENTER to continue

Press ENTER to continue and then press ENTER to read through the license. Once you’re done reading the license, you’ll be prompted to approve the license terms:

Output

Do you approve the license terms? [yes|no]

As long as you agree, type yes.

At this point, you’ll be prompted to choose the location of the installation. You can press ENTER to accept the default location, or specify a different location to modify it.

Output

Anaconda3 will now be installed into this location: /home/sammy/anaconda3 - Press ENTER to confirm the location - Press CTRL-C to abort the installation - Or specify a different location below [/home/sammy/anaconda3] >>>

The installation process will continue, it may take some time.

Once it’s complete you’ll receive the following output:

Output

... installation finished. Do you wish the installer to prepend the Anaconda3 install location to PATH in your /home/sammy/.bashrc ? [yes|no] [no] >>>

Type yes so that you can use the conda command. You’ll next see the following output:

Output

Prepending PATH=/home/sammy/anaconda3/bin to PATH in /home/sammy/.bashrc A backup will be made to: /home/sammy/.bashrc-anaconda3.bak ...

In order to activate the installation, you should source the ~/.bashrc file:

• • source ~/.bashrc

Once you have done that, you can verify your install by making use of the conda command, for example with list:

• • conda list

You’ll receive output of all the packages you have available through the Anaconda installation:

Output

# packages in environment at /home/sammy/anaconda3: # _ipyw_jlab_nb_ext_conf 0.1.0 py36he11e457_0 alabaster 0.7.10 py36h306e16b_0 anaconda 5.0.1 py36hd30a520_1 ...

Now that Anaconda is installed, we can go on to setting up Anaconda environments.

Setting Up Anaconda Environments

Anaconda virtual environments allow you to keep projects organized by Python versions and packages needed. For each Anaconda environment you set up, you can specify which version of Python to use and can keep all of your related programming files together within that directory.

First, we can check to see which versions of Python are available for us to use:

• • conda search "^python$"

You’ll receive output with the different versions of Python that you can target, including both Python 3 and Python 2 versions. Since we are using the Anaconda with Python 3 in this tutorial, you will have access only to the Python 3 versions of packages.

Let’s create an environment using the most recent version of Python 3. We can achieve this by assigning version 3 to the python argument. We’ll call the environment my_env, but you’ll likely want to use a more descriptive name for your environment especially if you are using environments to access more than one version of Python.

• • conda create --name my_env python=3

We’ll receive output with information about what is downloaded and which packages will be installed, and then be prompted to proceed with y or n. As long as you agree, type y.

The conda utility will now fetch the packages for the environment and let you know when it’s complete.

You can activate your new environment by typing the following:

• • source activate my_env

With your environment activated, your command prompt prefix will change:

Within the environment, you can verify that you’re using the version of Python that you had intended to use:

• • python --version

Output

Python 3.6.0 :: Continuum Analytics, Inc.

When you’re ready to deactivate your Anaconda environment, you can do so by typing:

• • source deactivate

Note that you can replace the word source with . to achieve the same results.

To target a more specific version of Python, you can pass a specific version to the python argument, like 3.5, for example:

• • conda create -n my_env35 python=3.5

You can update your version of Python along the same branch (as in updating Python 3.5.1 to Python 3.5.2) within a respective environment with the following command:

• • conda update python

If you would like to target a more specific version of Python, you can pass that to the python argument, as in python=3.3.2.

You can inspect all of the environments you have set up with this command:

• • conda info --envs

Output

# conda environments: # my_env /home/sammy/anaconda3/envs/my_env my_env35 /home/sammy/anaconda3/envs/my_env35 root * /home/sammy/anaconda3

The asterisk indicates the current active environment.

Each environment you create with conda create will come with several default packages:

• openssl

• pip

• python

• readline

• setuptools

• sqlite

• tk

• wheel

• xz

• zlib

You can add additional packages, such as numpy for example, with the following command:

• • conda install --name my_env35 numpy

If you know you would like a numpy environment upon creation, you can target it in your conda create command:

• • conda create --name my_env python=3 numpy

If you are no longer working on a specific project and have no further need for the associated environment, you can remove it. To do so, type the following:

• • conda remove --name my_env35 --all

Now, when you type the conda info --envs command, the environment that you removed will no longer be listed.

Updating Anaconda

You should regularly ensure that Anaconda is up-to-date so that you are working with all the latest package releases.

To do this, you should first update the conda utility:

• • conda update conda

When prompted to do so, type y to proceed with the update.

Once the update of conda is complete, you can update the Anaconda distribution:

• • conda update anaconda

Again when prompted to do so, type y to proceed.

This will ensure that you are using the latest releases of conda and Anaconda.

Uninstalling Anaconda

If you are no longer using Anaconda and find that you need to uninstall it, you should start with the anaconda-clean module which will remove configuration files for when you uninstall Anaconda.

• • conda install anaconda-clean

Type y when prompted to do so.

Once it is installed, you can run the following command. You will be prompted to answer y before deleting each one. If you would prefer not to be prompted, add --yes to the end of your command:

anaconda-clean

This will also create a backup folder called .anaconda_backup in your home directory:

Output

Backup directory: /home/sammy/.anaconda_backup/2017-01-25T191831

You can now remove your entire Anaconda directory by entering the following command:

• • rm -rf ~/anaconda3

Finally, you can remove the PATH line from your .bashrc file that Anaconda added. To do so, first open nano:

• • nano ~/.bashrc

Then scroll down to the end of the file (if this is a recent install) or type CTRL + W to search for Anaconda. Delete or comment out the following lines:

/home/sammy/.bashrc

# added by Anaconda3 4.2.0 installer export PATH="/home/sammy/anaconda3/bin:$PATH"

When you’re done editing the file, type CTRL + X to exit and y to save changes.

Anaconda is now removed from your server.

Conclusion

This tutorial walked you through the installation of Anaconda, working with the conda command-line utility, setting up environments, updating Anaconda, and deleting Anaconda if you no longer need it.

You can use Anaconda to help you manage workloads for data science, scientific computing, analytics, and large-scale data processing.