.. py:function:: add_diagram_edge(diagram, src, left, dst, expr, points = None) Add a graphical edge between two equations in a graphical diagram. * The source of the edge is identified by the local variable defined in the source equation. * The destination of the edge is identified by the parameter of the expression of the target equation. It is an ``ExprId`` instance referring to the left variable. To ease the creation of graphical diagrams, the destination of the edge can be specified with an integer, representing the input pin index of the target equation. :Parameters: **diagram** : :obj:`suite.NetDiagram` Diagram containing the source and destination equations. The diagram specified can be either graphical or textual, or it can be ``None``. However, it cannot be ``None`` if the scope contains at least one diagram. **src** : :obj:`suite.Equation` Source equation of the edge. **left** : :obj:`suite.LocalVariable` Local variable associated with the edge. **dst** : :obj:`suite.Equation` Target equation of the edge. **expr: Union[suite.Expression]** Parameter to connect to the edge or the input pin index of the target equation. **points** : :obj:`List`\[:obj:`Tuple`\(:class:`python:int`, :class:`python:int`)], default: :data:`python:None` Coordinates of the segments composing the edge, expressed in 1/100th of mm. When ``None``, the value is set to ``[(0, 0), (0, 0)]`` so that the SCADE Editor computes default positions when the model is loaded. :Returns: :obj:`suite.Edge` .. .. !! processed by numpydoc !!