Pure python & envs using Pip

I. Python+pip on Linux:

https://www.digitalocean.com/community/tutorials/how-to-install-python-3-and-set-up-a-local-programming-environment-on-centos-7

1. Need OpenSSL to avoid error: (and configure ./configure --with-ssl)

wget https://www.openssl.org/source/openssl-1.1.1g.tar.gz
tar -xf openssl-1.1.1g.tar.gz
cd openssl-1.1.1g

./config --prefix=/home1/p001cao/local/app/tool_dev/openssl \
--openssldir=/home1/p001cao/local/app/tool_dev/openssl

make -j 8 

make install 

2. Need "libffi" to avoid "_ctypes" error

wget https://github.com/libffi/libffi/releases/download/v3.3/libffi-3.3.tar.gz

tar -xf libffi-3.3.tar.gz
cd libffi-3.3

./configure --prefix=/home1/p001cao/local/app/tool_dev/libffi-3.3

Download 

export PYTHON_VERSION=3.7.5

curl -O https://www.python.org/ftp/python/${PYTHON_VERSION}/Python-${PYTHON_VERSION}.tgz tar -xvzf Python-${PYTHON_VERSION}.tgz cd Python-${PYTHON_VERSION}

Build and install Python#

Configure, make, and install Python:

./configure \ --prefix=/uhome/p001cao/local/app/python/${PYTHON_VERSION} \ --enable-shared \ --enable-ipv6 \ LDFLAGS=-Wl,-rpath=/uhome/p001cao/local/app/python/${PYTHON_VERSION}/lib,--disable-new-dtags

make -j 8 

make install 

REF; https://docs.rstudio.com/resources/install-python-source/

create module python3

set topdir /home1/p001cao/local/app/tool_dev/python37
module load openSSL

prepend-path    PATH                    $topdir/bin

prepend-path    INCLUDE         $topdir/include

prepend-path    LD_LIBRARY_PATH         $topdir/lib

Test: 
module load tool_dev/python37
python3 -V

python3 -m pip install --upgrade pip
python3 -m pip install --upgrade pip --trusted-host pypi.org --trusted-host files.pythonhosted.org

2. Setting Up a Virtual Environment

https://packaging.python.org/guides/installing-using-pip-and-virtual-environments/

Setting up a programming environment provides us with greater control over our Python projects and over how different versions of packages are handled. 

venv (for Python 3) and virtualenv (for Python 2) allow you to manage separate package installations for different projects. They essentially allow you to create a “virtual” isolated Python installation and install packages into that virtual installation. When you switch projects, you can simply create a new virtual environment and not have to worry about breaking the packages installed in the other environments.

Choose which directory you would like to put your Python programming environments in, or create a new directory in installing dir of python:

cd  /uhome/p001cao/local/python/Python37

mkdir enviroments

cd  enviroments

module load python/python37

python3 -m venv    py37impi

source py37impi/bin/activate

create module python/python37

set               topdir            /uhome/p001cao/local/python/Python37/enviroments/py37impi
module load openSSL
prepend-path    PATH                    $topdir/bin
prepend-path    LD_LIBRARY_PATH         $topdir/lib
prepend-path    INCLUDE                 $topdir/include

if { [ module-info mode load ] } {
    puts stdout "source $topdir/bin/activate;"
} elseif { [ module-info mode remove ] } {
    puts stdout "deactivate"
}

2. Install packages:

load corresponding envs:
module load python/py37impi

python3 -m pip install --upgrade pip

pip3 install tess ovito numpy scipy matplotlib mpi4py impi




III. Some problems:
SSL:
https://joshspicer.com/python37-ssl-issue

wget https://www.openssl.org/source/openssl-1.0.2q.tar.gz
tar xvf openssl-1.0.2q.tar.gz
cd   openssl-1.0.2q
./config  --prefix=/uhome/p001cao/local/openssl-1.0.2
make
make install

create module openSSL

set               topdir           /uhome/p001cao/local/openssl-1.0.2

prepend-path    PATH                    $topdir/bin

prepend-path    LD_LIBRARY_PATH         $topdir/lib

prepend-path    INCLUDE                 $topdir/include

IV. Install package from source

cd sourceFolder

pip install -e .