Class Graph

A Graph is composed of nodes and edges (i.e., Node and Edge objects).

Note that for general discussion, we use the words “step” and “node” interchangeably in the following documentation. The python code defines a Step class and a Node class which are aliases of each other. We recommend using the Node class. The Step class is deprecated.

class mflowgen.components.Graph

Graph of nodes and edges (i.e., Node and Edge).

ADK-related

The following methods help interface with the ADK.

Graph.set_adk(adk)

Sets the ASIC design kit.

Searches the paths in “Graph.sys_path” for ADKs (analagous to python sys.path).

Parameters

adk – A string representing the subdirectory name of the ADK

Graph.get_adk_node()

Gets the Node object representing the ASIC design kit.

Returns

The Node object that was constructed from the currently set ADK.

Adding Nodes

Graph.add_node(node)

Adds a Node to the graph as a node.

The name of the new Node cannot conflict with any nodes that already exist in the graph. This method fails an assertion if given a duplicate node name.

Parameters

node – A Node object

Graph.get_node(node_name)

Gets the Node object with the given name.

Parameters

node_name – A string representing the name of the node from Node.get_name()

Graph.all_nodes()

Connecting Nodes Together

The Graph.connect_by_name() method is preferred when possible to keep code clean. This requires setting up nodes such that the inputs and outputs are name-matched (e.g., nodeA has output foo and nodeB has input foo).

Graph.connect(l_handle, r_handle)

Graph.connect_by_name(src, dst)

Parameter System

Graph.update_params(params)

Updates parameters for all nodes in the graph.

Calls Node.update_params() for each node in the graph with the given parameter dictionary.

Parameters

params – A dict of parameter names (strings) and values

Advanced Graph-Building

Graph.param_space(node, param_name, param_space)

Spins out new copies of the node across the parameter space.

For example, for a graph like this:

+-----+    +-----------+    +-----------+
| foo | -> |    bar    | -> |    baz    |
|     |    | ( p = 1 ) |    |           |
+-----+    +-----------+    +-----------+

this call:

g = Graph()
(...)
g.param_space( 'bar', 'p', [ 1, 2, 3 ] )

will be transformed into a graph like this:

            +-----------+    +-----------+
        +-> |  bar-p-1  | -> |  baz-p-1  |
        |   | ( p = 1 ) |    |           |
        |   +-----------+    +-----------+
+-----+ |   +-----------+    +-----------+
| foo | --> |  bar-p-2  | -> |  baz-p-2  |
|     | |   | ( p = 2 ) |    |           |
+-----+ |   +-----------+    +-----------+
        |   +-----------+    +-----------+
        +-> |  bar-p-3  | -> |  baz-p-3  |
            | ( p = 3 ) |    |           |
            +-----------+    +-----------+

Parameters

• node – A string for the node name targeted for expansion

• param_name – A string for the parameter name

• param_space – A list of parameter values to expand to

Returns

A list of (parameterized) nodes (i.e., ‘bar-p-1’, ‘bar-p-2’, and ‘bar-p-3’).