First Tutorial
==============

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   <iframe width="560" height="315"
    src="https://www.youtube.com/embed/taQVjBoCdF8" frameborder="0"
    gesture="media" allow="encrypted-media" allowfullscreen></iframe>


In this first nodeworks tutorial, we'll test your installation of nodeworks by
making the simple sine and cosine wave plot. To begin, launch a new session of
nodeworks from a terminal with::

  $ nodeworks

Step 1: Add the nodes
---------------------
First we will add four nodes: a ``Range`` node, two ``Trig`` nodes and a
``Plot`` node. To add a node to the sheet, right click on the Nodeworks canvas
and a context menu will pop up. Navigate to **Add Node** at the bottom, then to
**numpy** and then to click on ``Range`` as shown below.

.. figure:: ./images/first_tutorial_1.png
   :width: 800 px
   :align: center
   :figclass: align-center

.. note::
  You can delete a node by highlighting it (either left click on it or drag a
  box surrounding it) and pressing delete on the keyboard. Highlighted nodes can
  also be moved around the sheet by dragging while holding left click.  The
  sheet itself can be panned over by holding and dragging the wheel button. A
  map of the sheet is shown in the upper left-hand corner.

Change the range step size to 0.1 for a smoother curve. The ``Trig`` node is
also located in the numpy node group and can be added in the same way or, since
we know the name of the node we want to add, you can shortcut to the node
library short by left clicking on the screen where you want to add the node and
typing the node name directly on the keyboard. A shortened dropdown list will
appear with nodes matching the search, as shown below. Set the operation of the
second ``Trig`` node to cos. Finally, add the ``Plot`` node which is located in
the ``matplotlib`` group.

.. figure:: ./images/first_tutorial_2.png
   :width: 800 px
   :align: center
   :figclass: align-center

.. note::
  `Ctrl+c` and `Ctrl+v` shortcut keys could also be used to copy and paste a
  second ``Trig`` node.


Step 2: Connect the nodes
-------------------------
The four nodes need to be connected to form a process or workflow. Left click on
the output terminal of the ``Range`` node, ``range``. Drag the connection over
to the ``input`` terminal of either of the ``Trig`` nodes. Make a similar
connection to the other ``Trig`` node.  Connect both of the ``Trig`` ``array``
output terminals to the ``y`` input terminal of the ``Plot`` node. The final
connection is made from the ``range`` terminal to the ```x`` input terminal of
the ``Plot`` node.

.. figure:: ./images/first_tutorial_3.png
   :width: 800 px
   :align: center
   :figclass: align-center


Step 3: Run the sheet
---------------------
Run the sheet by pressing the `Run` button on the top toolbar (third from left).
The sheet should look similar to the above figure. The sheet can be saved by
pressing the ``Save`` button (second toolbar button on the left) which creates a
node chart (\*.nc) file that can be reopened in the Main Menu (leftmost toolbar
button).

This simple tutorial only scratches surface of the nearly unlimited
possibilities that Nodeworks offers. If you are interested in learning more
advanced features of Nodeworks or even developing your own nodes or interfaces
with other programs, please see our Developers section. If you are most
interested in the capability of Nodeworks to interface with the MFiX GUI, please
see the MFiX Interface section. In addition, we release collections of nodes or
specialized nodes called Toolsets which contain more advanced examples on their
use and functionality. Please direct any questions or feedback to the mailing
list.

Thank you for your interest in Nodeworks. Happy Noding!