Cookbook

The cookbook contains recipes for common or useful tasks.

PyCell Template

PyCell is a plugin included with Quantum. It provides the ability to author new cells in Python. We provide a general template to provide a quick start to building new cell types in native Python.

  1. Create the Python file that will define your cell. You should put this file in your PyCell user directory. This is located at /Users/[username]/.kivy/mods/UDPyCell.

    Attention

    This process will change in the future. Instead of creating the file in a specific location, you will be able to browse to the file from Quantum and choose to install the file for either all users or only for the current user.

  2. Copy and paste the following template into your new file:

    PyCell Cell Template 
    import PyCell
from PyCell.custom_cell import Custom

class MyCell(Custom):
    """
    Provide your docstring for MyCell here.
    """

    def __init__(self):
        self.inputs = {}  # add your own input variables
        self.outputs = {}  # add your own output variables
        self.inflows = ['>>']  # remove this line if the cell doesn't require token-based execution
        self.outflows = {}  # add any token outputs here, remove if you don't need it
        # Add any additional initialization you might need

    def process(self):
        # Add your process code here
        return super().process()  # this return line is required

 # Be sure to add your new cell to the registry so that it will be
 # available to Quantum:
 PyCell.registry.append({
     'name': 'MyCell',
     'module': 'UDPyCell.my_cell',
     'categories': ['Category1','Category2','MyCell']
     })

    To make sure your cell appears in Quantum, you need to make sure it is added to PyCell’s registry. You see this code in the last 5 lines. Here’s an explanation of the dictionary items:

    • name: This should match the name of your class exactly.
    • module: The format is UDPyCell.[filename]. Replace [filename] with the name of your python file.
    • categories: This list determines the contextual menu path to take in order to reach your cell. This is how the user will navigate the right click to use your cell.

Graph Database

The underlying graph database uses the TinkerPop API, which means you can use you own tools of choice to manipulate the application data.

Attention

Our current graph database provider is TitanDB 0.5.4, but this will change in the future. Regardless what data provider we may use in the future, it will use the TinkerPop API so you can continue to rely on having the Gremlin query language as the method of interaction with the underlying data.

Titan DB, our current graph database, exposes a Gremlin console through a website that you can access. You can find this console at http://localhost:8182. From here you can execute Gremlin queries to manipulate the data. For example, you can clear out the entire database:

Gremlin Console 
gremlin> g.V.remove()
==> null
gremlin> g.commit()
==> null

If you have Quantum running, the graph database will be running and you will be able to connect to it. However, if you do not have Quantum open, then the graph database server may not be running and in this situation, you may need to manually start the server.

Terminal 
$ /Applications/Quantum.app/Contents/Frameworks/titan-0.5.4-hadoop2/titan.sh start

Generate an Eclipse Project

Quantum projects uses cmake as the build system. Cmake can generate eclipse project files if you use that as your IDE. As an example, this section will provide a recipe for creating an eclipse project with PyCell:

$ git clone https://github.com/QuantumActuary/Quantum-PyCell.git
$ cd Quantum-PyCell
$ cmake -G"Eclipse CDT4 - Unix Makefiles"

Now you can import this project in eclipse by going to File > Import > Existing Project.

Pip Install Python Modules

For developers, you may wish to install python modules into Quantum’s Python environment. You can do this like so:

$ quantum -m pip install <package name>