IPE is an extensible drawing editor software specially targeted at making figures for inclusion into LaTeX documents, as well as multi-page PDF presentations. This repository contains a small extension of IPE, a so-called ipelet. The ipelet in this repository aims at provinding an automatic tool for drawing linear arrangements of graphs, also called embeddings.

This ipelet is a tool aimed at easing the process of drawing and manually editing linear arrangements of graphs. It can draw a graph from a head vector input and also from an edge list. Vertices can be mapped to positions indicated by their indices, or indicated by an arrangement function and/or an inverse arrangement function. Users can also label the vertices using math-text, and calculate metrics on the linear arrangement.

Users will find a complete guide at this ipelet's wiki. Here is a screenshot of the main dialog:

and a few examples of what it can do:

Copy all the .lua files into your ipelet directory. In Ubuntu, this is ~/.ipe/ipelets/. Visit the home webpage of IPE for more information.

• Updated wiki

• Implemented drawing of bipartite embeddings.
• Minor adjustments in (vertical and horizontal) spacing between embeddings.

• Merged the two ipelets made on July 23rd, 2021 into a single one. This way it is easier to input the data.

• Added new ipelete to visualize arrangements in a circular ordering.
• Refactored much of the code so as to avoid repetition.

• Added option to bicolor the vertices of the graph. The algorithm will successfully bicolor the vertices following the constraints of the graph coloring problem if the graph is bipartite.

• Place position labels in the same vertical line as the vertices.

• Added calculation of the number of edge crossings.

• When using the head vector, add the arcs to the ipe document in a way that the 'forward' arrow points from the head to the dependent. In other words, edges now follow the natural direction of the edge (u,v), i.e., from u to v, where u is the head and v is the dependent.
• Improved automatic spacing, and corrected spacing when not using automatic spacing.

• Vertex labels now have to be separated with a '&' (the delimiter) character. Therefore, the string "a & b & c & d" produces the strings "a ", " b ", " c " and " d".

• Implemented a better automatic spacing that takes into account all the dimensions of a text object, namely, its height, width and depth. Only available on IPE 7.2.24 or newer.

• Implemented a first approach to a better vertical alignment of the arrangements. Waiting for the next release of IPE to be able to retrieve the height and depth of a text object.

• Added more slots in the dialog for arrangements. Now users can draw up to 4 arrangements for the same graph without having to open the ipelet as many times as arrangements they want to draw.

• Moved usage guide from this README to the brand new wiki for this ipelet.

Renamed 'linear sequence' by 'head vector' and added new features:

• indicate vertex labels in a separate input text box. This works even for head vectors.
• modify the arrangement of a head vector by specifying a linear arrangement or an inverse linear arrangement.

• Split the main file embedding_visualizer.lua into several files, each starting with ev_.

• Extended the Ipelet to apply an automatic spacing between the labels of the vertices.
• Updated the examples and added new ones.

• Extended Ipelet to admit linear sequences.
• Uploaded new examples (of the new feature) and updated old examples.
• Code is now substantially better documented.

• The objects created (marks, arcs, labels, ...) are selected to ease future manipulations when several arrangements are to be added to the document.

• Display markers as the vertices of the graph.
• Extended the format of input strings.

• Extended the ipelet to admit two diferent representations of a linear arrangement. The actual linear arrangement and the inverse linear arrangement (the so far so-called sequence).
• Fixed bugs (in the first extension).
• Allow users to choose the x offset.
• In case the arrangement was given (not the inverse), add the labels of the positions at the below the vertices.

• Extended the ipelet to accept string and character values for the description of the graph and the embedding.
• Change label's text to say "Sequence" instead of "Embedding".

• Created repository with first version of the ipelet.