Graph Creator

  • Graph Creator

    Grade:

    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.

    Activity

    Instructions

    Use the Vertex Tools and Edge Tools to create your graph, and then use the Graph Explorer to investigate your graph and the problem it represents. At any point the Clear All button on the bottom right can clear your entire workspace.

     

    Vertex Tools

    • 3550addvertexAdd Vertex 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.
    • 3550 select_vertexSelect Vertex 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.
    • 3550 snap-to-gridSnap 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.
    • Label 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.
    • Show Degree toggles between showing and hiding the degree of each vertex.

    Edge Tools

    • 3550 add-edgeAdd Edge 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.
    • 3550 add-directed-edgeAdd Directed Edge adds directed edges between two vertices. The direction is determined by the order in which the vertices are clicked.
    • 3550 bend-edgeBend Edge 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.
    • 3550 select-edgeSelect 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.
    • 3350 complete-graphComplete Graph 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.
    • Weight 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.
    • Show Weight toggles between showing and hiding the weights. Hiding the weight does not erase the value.
    • Directed toggles between showing an edge as a directed or undirected edge.
    • Direction switches the direction of a directed edge.

    Graph Explorer

    • 3550 highlighterHighlighter 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.

    Common Tools

    • 3550 delete-selectedDelete Selected deletes individual vertices or edges using the tools on the respective toolbars.
    • 3550 color-paletteColor Palette 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.
    • 3550 hide-toolbarHide Toolbar 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.