I'm brand new to python, using terminal, pip and virtual env.
From what I gather, the command 'source' activates the virtual environment and anything you do after that stays in the virtual environment like installing something with pip installs it only in your virtual environment. However, do I need to actually create a folder or choose a location first before I run source? In other words, does source create the virtual environment or only activate one that already exists?
This stuff is really hard to wrap my head around. I think one of the things that is hindering my development is that I'm not familiar with certain directory structures like bin, ect.
Once you create a virtualenv, you will see source created in the directory.
You must cd to that particular source and do source activate to start working on that particular virtualenv. Each virtualenv has its own source.
You can also use virtualenv wrapper to make things easier.
Look, you need to create the virtual enviroment first, with something like this:
virtualenv venv
Where 'venv' is the destination directory. After that you can run:
source venv/bin/activate
You can take a look at virtualenv help with:
virtualenv --help
Related
I have a very simple question. According to this snippet, I have created a virtualenv named newConda in this address C:\Users\....\Envs. So, my question is: how can I create this virtualenv in any other path of my choice, for example, in E:\programming\New folder?
One of the advantages of virtualenvwrapper is that it stores all your virtual environments in one place so it can manage them at once.
If you want to create a virtual environment in another place you just use virtualenv instead of virtualenvwrapper.
If you want to store all your virtualenvwrapper's virtual environments in a different directory define (change) environment variable WORKON_HOME:
set WORKON_HOME=E:\programming\New
I have a fresh Julia instalation on a machine that I want to use as a number-crunching server for various persons on a lab. There seems to be this nice package called jupyterhub wich makes the Jupyter Notebook interface avaible to various clients simultaneusly. A web page which I am unable to find again began suggesting something like "first install IJulia globally, then install JupyterHub..."
I cannot seem to find a nice way to install ONE package globally.
Update
In Julia-v0.7+, we need to use JULIA_DEPOT_PATH instead of JULIA_PKGDIR and the LOAD_PATH looks something like this:
julia> LOAD_PATH
3-element Array{Any,1}:
Base.CurrentEnv()
Any[Base.NamedEnv("v0.7.0"), Base.NamedEnv("v0.7"), Base.NamedEnv("v0"), Base.NamedEnv("default"), Base.NamedEnv("v0.7", create=true)]
"/Users/gnimuc/Codes/julia/usr/share/julia/stdlib/v0.7"
Old Post
"first install IJulia globally, then install JupyterHub..."
I don't know whether this is true or not, by following these steps below, you can install IJulia after you installed Jupyterhub.
Install packages system-wide/globally for every user
this question has already been answered here by Stefan Karpinski. so what we need is just use this method to install the IJulia.jl package.
There's a Julia variable called LOAD_PATH that is arranged to point at two system directories under your julia installation. E.g.:
julia> LOAD_PATH
2-element Array{Union(ASCIIString,UTF8String),1}:
"/opt/julia-0.3.3/usr/local/share/julia/site/v0.3"
"/opt/julia-0.3.3/usr/share/julia/site/v0.3"
If you install packages under either of those directories, then everyone using that Julia will see them. One way to do this is to run julia as a user who can write to those directories after doing export JULIA_PKGDIR=/opt/julia-0.3.3/usr/share/julia/site in the shell. That way Julia will use that as it's package directory and normal package commands will allow you to install packages for everyone....
Make IJulia working with Jupyterhub
in order to make IJulia and Jupyterhub working with each other for all the users, you should copy the folder your/user/.local/share/jupyter/kernels/julia/ to /usr/local/share/jupyter/kernels/. I write down some of the steps that I used in my test Dockerfile. the code is ugly, but it works.
Steps: (after you successfully installed Jupyterhub)
note that, you should do the following steps as root and I assume that your julia was globally installed at /opt/julia_0.4.0/.
make our global package directory and set up JULIA_PKGDIR:
mkdir /opt/global-packages
echo 'push!(LOAD_PATH, "/opt/global-packages/.julia/v0.4/")' >> /opt/julia_0.4.0/etc/julia/juliarc.jl
export JULIA_PKGDIR=/opt/global-packages/.julia/
install "IJulia" using package manager:
julia -e 'Pkg.init()'
julia -e 'Pkg.add("IJulia")'
copy kernelspecs to /usr/local/share/jupyter/kernels/ which can be used by any new user added by Jupyterhub:
jupyter kernelspec list
cd /usr/local/share/ && mkdir -p jupyter/kernels/
cp -r /home/your-user-name/.local/share/jupyter/kernels/julia-0.4-your-julia-version /usr/local/share/jupyter/kernels/
I've had many questions about Python for which a suggested answer is often "use virtualenv", but I have a (lovingly maintained and perfectly functioning) Python installation that I'm loath to disturb.
I want to be absolutely sure, so I'll ask twice: Does use of virtualenv in any way disturb my "real" Python installation? Using virtualenv does not in any way modify the files or paths in my "real" installation, right?
Virtualenv creates separated Python environment. Python interpreter is linked from one of system-installed that you choose creating virtualenv( --python commandline switch) and, optionally, wheater use or not system site-packages (--system-site-packages).
All packages that you install using virtualenv remains only on virtualenv directory site-packages folder and do not mess system packages.
Is it possible to set the path where the berkshelf plugin puts the cookbooks it installs? (As in the .berkshelf folder)
I am running Windows 7.
I am currently trying to install a mysql server using an opscode cookbook to a vm and here at work they have the %HOMEDRIVE% system variable set to a network drive. So when .berkshelf starts at the beginning of the Vagrantfile, it pushes the cookbooks to the network drive and it causes it to be slow and well, its not where it should be. Is there a fix to this?
VirtualBox did this as well, but I fixed it by altering the settings. I tried looking for some sort of equivalent settings for berkshelf, but the closest I got was for the standard berkshelf (thats not a vagrant plugin), it appears you can set this environment variable:
ENV['BERKSHELF_PATH']
Found here:
http://www.rubydoc.info/github/RiotGames/berkshelf/Berkshelf#berkshelf_path-class_method
I need to be able to have the cookbooks it reads from the berksfile store to my laptops local drive instead, as in my scenario I cannot have the mobility of the VM limited to the building because of files that are stored on the network.
Any incite would be much appreciated.
Perhaps its better to use the actual berkshelf over the vagrant plugin?
Thanks.
If you want to have the portability - a full chef-repo ready for chef-solo runs, better off using standalone berkshelf instead of the vagrant-berkshelf plugin - which is NOT that flexibly.
For complex cookbooks, I prefer to use standalone berkshelf as it allows me to do berks install --path chef/cookbooks to copy all cookbooks required from ~/.berkshelf/cookbooks, then I can just tar the whole thing and transfer to other machines for the same chef-solo run. some people use capistrano automate the tar and scp/rsync over the network. I just use rysnc/scp;-)
HTH
I have a relatively big project that has many dependencies, and I would like to distribute this project around, but installing these dependencies where a bit of a pain, and takes a very long time (pip install takes quite some time). So I was wondering if it was possible to migrate a whole virtualenv to another machine and have it running.
I tried copying the whole virtualenv, but whenever I try running something, this virtualenv still uses the path of my old machine. For instance when I run
source activate
pserve development.ini
I get
bash: ../bin/pserve: /home/sshum/backend/bin/python: bad interpreter: No such file or directory
This is my old directory. So is there a way to have virtualenv reconfigure this path with a new path?
I tried sed -i 's/sshum/dev1/g' * in the bin directory and it solved that issue. However, I'm getting a different issue now, my guess is that this sed changed something.
I've confirmed that I have libssl-dev installed but when I run python I get:
E: Unable to locate package libssl.so.1.0.0
E: Couldn't find any package by regex 'libssl.so.1.0.0'
But when I run aptitude search libssl and I see:
i A libssl-dev - SSL development libraries, header files and documentation
I also tried virtualenv --relocatable backend but no go.
Export virtualenvironment
from within the virtual environment:
pip freeze > requirements.txt
as example, here is for myproject virtual environment:
once in the new machine & environment, copy the requirements.txt into the new project folder in the new machine and run the terminal command:
sudo pip install -r requirements.txt
then you should have all the packages previously available in the old virtual environment.
When you create a new virtualenv it is configured for the computer it is running on. I even think that it is configured for that specific directory it is created in. So I think you should always create a fresh virtualenv when you move you code. What might work is copying the lib/Pythonx.x/site-packages in your virtualenv directory, but I don't think that is a particularly good solution.
What may be a better solution is using the pip download cache. This will at least speed up the download part of pip install. Have a look at this thread: How do I install from a local cache with pip?
The clean way seems to be with virtualenv --relocatable.
Alternatively, you can do it manually by editing the VIRTUAL_ENV path in bin/activate to reflect the changes. If you choose to do so, you must also edit the first line (#) of bin/pserve which indicates the interpreter path.