ChemApp for Python with a Bare Python Installation

This procedure explains how to install ChemApp for Python into a bare Python installation.

Windows

Download the relevent version of Python. For the current ChemApp for Python version, you need to download Python 3.9.1..
Install Python.

Double-click on the downloaded python-3.9.5-amd64 file. In the installation window, tick the “Add Python 3.9 to PATH” and choose customise installation and click next. On the Optional Features window, make sure that all of the checkboxes are ticked and as seen in the Figure below, and click next.

On the Advanced Options window seen in the Figure below, click on the “Install for all users” checkbox. This will change the install directory to C:\Program Files\Python39. This should be changed to C:\Python39 for simplification purposes.

After the installation, the window can be closed.
Additional installations.

To be able to install the ChemApp for Python package, setuptools and pip (a Python package manager) must be installed. These are installed by entering the following commands into the Command Prompt. The command prompt can be opened by pressing Windows-R (hold down the Windows key and press R), typing cmd, and pressing Enter.
1. install pip:
```
curl https://bootstrap.pypa.io/get-pip.py | python
```
2. install setuptools:
```
pip install setuptools
```
  If you are unsuccessful with the installation, a more detailed procedure can be found here. Or consider to switch to one of the IDE installation methods.
Install new packages using pip.

In the command prompt, new packages can be installed with the following command: pip install <new-package>. Try it out by installing the numpy package:
```
pip install numpy
```
Display packages installed on Python.

The following command can be used to see the packages installed on Python.
```
pip list
```
Download ChemApp for Python’s free Light edition.

ChemApp for Python Light can be downloaded from the GTT website. The dowloaded file should be stored in an easily accessible location. In this example, the file is downloaded to
```
C:\Python36\Scripts\python-packages\
```
The “python-packages” folder was created manually.
Install ChemApp for Python Light.

In the command prompt, type-in the following command to install ChemApp for Python Light
```
pip install C:\Python36\Scripts\python-packages\chemapp-0.3.2-gtt-win-chemapp7.2.0-python3.6.2.tar.gz
```
The name of the downloaded file could differ depending on the ChemApp for Python release version.
Open python.

Python can be opened by typing “python” in the command prompt. An alternative method is to press the Windows button, search for “python” and clicking on “Python 3.9 (64-bit)” under Apps.

Linux

The following procedure must be used to use ChemApp for Python in bare Python.

Install Python.

Install Python 3.9 through the terminal with the following command:
```
sudu apt-get install python3
```
Ensure that Python 3.9.1 is installed by downloading it here. Unzip the file, with a name like Python-3.9.1.tgz in an easy to locate location. Then cd to the Python-3.9.1 file in the terminal and run the following commands:
```
sudo make
```
And,
```
sudo make install
```
Verify that Python 3.9.1 was installed correctly by executing the following command:
```
python3 -V
```
Install ChemApp for Python.

For this installation it is required to have obtained the ChemApp for Python *.tar.gz file. cd to where the ChemApp for Python package is stored and install ChemApp for Python through the terminal with the following command:
```
pip install chemapp_816-linux-chemapp_8.1.6-python3.9.1.tar.gz
```
Ensure that ChemApp for Python installed successfully by running the following command in the terminal:
```
pip list
```
A list of all the installed packages will appear. Below is an example of the list showing that chemapp is installed.
```
certifi                            2017.7.27.1
cffi                               1.10.0
chardet                            3.0.4
chemapp                            816
click                              6.7
cloudpickle                        0.4.0
clyent                             1.2.2
colorama                           0.3.9
```
Running a Python file.

In order to run a *.py file run the command, shown below, in therminal. The file_path to the *.py file must be entered correctly in the terminal.
```
python file_path/*.py
```