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Use this vertex-edge tool to create graphs and explore them. Investigate ideas such as planar graphs, complete graphs, minimum-cost spanning trees, and Euler and Hamiltonian paths.
to create your graph, and then use the
to investigate your graph and the problem it represents. At any point the
button on the bottom right can clear your entire workspace.
creates a new vertex on your workspace. Vertices are automatically labeled sequentially A–Z then A'–Z'. The maximum number of vertices allowed on the workspace is 52.
selects one or several vertices to move them or change their properties. To select more than one vertex, either shift+click individual vertices or use your mouse to draw a rectangle around the vertices you would like to select.
Snap to Grid
displays a grid that all vertices will snap to when moved or added. This is helpful when arranging a graph into a rectangular array.
changes the letter label of a vertex. It can only be used on one vertex at a time. Labels are restricted to the letters A–Z and A'–Z' and must be unique.
toggles between showing and hiding the degree of each vertex.
adds an edge between two vertices. Click once on each endpoint to draw the edge. If you click the same vertex twice, it creates a loop. Several edges can be added between the same pair of vertices.
Add Directed Edge
adds directed edges between two vertices. The direction is determined by the order in which the vertices are clicked.
bends or stretches any existing edge. When the tool is activated, all edges will display a red control point. Move the control point to bend the edge.
selects one or several edges to change their properties. This tool cannot move edges. Several edges can be selected at once in the same manner as with the Select Vertex tool.
draws a complete graph using the vertices in the workspace. It erases all existing edges and edge properties, arranges the vertices in a circle, and then draws one edge between every pair of vertices.
sets the weight of an edge or set of edges. The default weight of all edges is 0. Weights can be any integer between –9,999 and 9,999.
toggles between showing and hiding the weights. Hiding the weight does not erase the value.
toggles between showing an edge as a directed or undirected edge.
switches the direction of a directed edge.
highlights vertices and edges. Several elements can be highlighted at once in the same manner as with the Select Vertex tool. Click the blank background to deselect everything. If edges are highlighted, a running Sum of All Weights will be displayed in the toolbar.
Highlight Euler Path
highlights edges on your graph to help you find an Euler path. Edges that would not create an Euler path are restricted.
Highlight Hamiltonian Path
highlights edges on your graph to help you find a Hamiltonian path. Edges that would not create a Hamiltonian path are restricted. A running Sum of All Weights will be displayed in the toolbar as you build your path.
deletes individual vertices or edges using the tools on the respective toolbars.
changes the color of selected vertices or edges. If an element color is changed, that will become the default color for new elements of that type.
is in the bottom center of the toolbar. Use it to hide the toolbar and give yourself more workspace to create and explore your graph.
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