# Question:Can Maple import the graphs generated by nauty or plantri  (an inspiration from Mathematica)

## Question:Can Maple import the graphs generated by nauty or plantri  (an inspiration from Mathematica)

Maple 2022

I've been asking a similar question：

How does Maple call external programs such as nauty?

Recently I used Mathematica to call these gadgets very succinctly, so I revisit the topic, and maybe Maple can do it as well, but I just didn't do it the right way.

• nauty and Traces are programs for computing automorphism groups of graphs and digraphs. There is a small suite of programs called gtools included in the package. For example, geng can generate non-isomorphic graphs very quickly.
• plantri and fullgen are programs for generation of certain types of planar graph.

We note that binary executables of above two programs for Windows are not officially available. Fortunately, I recently compiled them by cygwin.  Of course, other operating systems can make it easier to use them. See attached two compressed files of compiled nauty and plantri programs for Windows.

The official websites of the two programs are listed below.

So, I found that Mathematica works very well for running these programs by Import. We list the following two examples: first example is to get all non-isomorphic 10-order 2-partite connected graph, and the second example is to get all 14-order non-isomorphic  quadrilateral graphs (the planar graphs in which any face is 4-face).

```glist10 = Import["!D:/nauty27r3/geng -c -b 10", "Graph6"]; // AbsoluteTiming
Length[glist10]```

`g14 = Import["!D:/plantri52/plantri 14 -q -g ", "Graph6"] // AbsoluteTiming`

I tried maple's Import or ImportGraph functions, but both failed.

```restart:
with(GraphTheory):
L:=ImportGraph("!D:/nauty27r3/geng -c -b 10 -g",output=list):
L2:=Import("!D:/nauty27r3/geng -c -b 10 -g"):
```

Error, invalid input: GraphTheory:-ImportGraph uses a 2nd argument, format (of type {string, symbol}), which is missing
Error, (in Import) must specify format for this input

The problem seems to be not recognizing compilations symbols " !".  I don't know if Maple can do this like mathematica.

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