conda_basics.md

Set up a Python environment

Anaconda

Anaconda is an open source software that contains Jupyter, spyder, etc that are used for large data processing, data analytics, heavy scientific computing.

Anaconda works for R and Python programming language.

Package versions are managed by the package management system conda.

• Installing Anaconda: Head over to anaconda.com and install the latest version of Anaconda.

Why do we need to set up a virtual environment?

Like many other languages Python requires a different version for different kind of applications. The application needs to run on a specific version of the language because it requires a certain dependency that is present in older versions but changes in newer versions.

Virtual environments makes it easy to ideally separate different applications and avoid problems with different dependencies.

Using virtual environment we can switch between both applications easily and get them running.

There are multiple ways of creating an environment using virtualenv, venv and conda. Conda command is preferred interface for managing installations and virtual environments with the Anaconda Python distribution.

Steps of creating a virtual environment using conda interface

1. Check if conda is installed in your path.

   • Open up a terminal.

   • Type conda -V and press enter.

   • If the conda is successfully installed in your system you should see a similar output.

       user@pc:~$ conda -V
       conda 4.9.2
     

2. Set up the virtual environment.

   • You create a new environment by using: conda create -y -n [env-name] python=[x.x]

   • Now replace the env-name with the name you want to give to your virtual environment and replace x.x with the python version you want to use.

       user@pc:~$ conda create -y -n env-py38-evoml-python-commons python=3.8
           ...
     
       # To activate this environment, use
       #
       #     $ conda activate env-py38-evoml-python-commons
       #
       # To deactivate an active environment, use
       #
       #     $ conda deactivate
     

3. Get a list of all my environments Active environment shown with: conda env list

        user@pc:~$ conda env list
        # conda environments:
        #
        base             *  /opt/anaconda3
        env-py38-evoml-python-commons      /opt/anaconda3/envs/env-py38-evoml-python-commons
   

4. Activating the virtual environment

   • To activate the virtual environment, enter the given command: conda activate env-name

   • Replace your given environment name with env-name.

   • When conda environment is activated it modifies the PATH and shell variables points specifically to the isolated Python set

       user@pc:~$ conda activate env-py38-evoml-python-commons
       (env-py38-evoml-python-commons) user@pc:~$
     

5. Deactivating the virtual environment.

   • To come out of the particular environment type the following command. The settings of the environment will remain as it is.

       user@pc:~$ conda deactivate
       user@pc:~$
     

6. Deletion of virtual environment.

   • If you no longer require a virtual environment, delete it using the following command: conda env remove -n [env-name]

   • Replace your environment name with env-name

       user@pc:~$ conda env remove -n env-py38-evoml-python-commons