SHORTG(1)

okay bestie, pull up a chair, because this is shortg 💖 — it lives in section 1 of the manual under User Commands, and honestly? it's giving graph-theory legend. no cap.

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✨ NAME ✨

shortg — the manual page for shortg 2.9.3 🫶

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🦋 SYNOPSIS 🦋

shortg [-qvkdu] [-i# -I#:# -K#] [-fxxx] [-S|-t] [-Tdir] [-Z#] [infile
[outfile]]

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👑 DESCRIPTION 👑

Remove isomorphs from a file of graphs. that's the whole assignment, and it eats every time 🔥

If outfile is omitted, it is taken to be the same as infile. If both infile and outfile are omitted, input will be taken from stdin and written to stdout.

The output file has a header if and only if the input file does. no extra vibes, no missing vibes, exactly matching energy ✨

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• -s — force output to sparse6 format 💅
• -g — force output to graph6 format 💅
• -z — force output to digraph6 format. If none of -s, -z, -g are given, the output format is determined by the header or, if there is none, by the format of the first input graph. The output format determines the sorting order too. As an exception, digraphs are always written in digraph6 format. 🌀
• -S — use sparse representation internally. Heads up bestie: note that this changes the canonical labelling. Multiple edges are not supported. One loop per vertex is ok. 🎀
• -t — use Traces. Note that this changes the canonical labelling. Multiple edges, loops, directed edges are not supported, nor invariants. 😭
• -k — output graphs have the same labelling and format as the inputs. Without -k, output graphs have canonical labelling. -s, -g, -z are ineffective if -k is given. 👑
• -v — write to stderr a list of which input graphs correspond to which output graphs. The input and output graphs are both numbered beginning at 1. A line like

23 : 30 154 78

means that inputs 30, 154 and 78 were isomorphic, and produced output 23. so like, a little group chat of graphs fr fr 💬

• -d — include in the output only those inputs which are isomorphic to another input. If -k is specified, all such inputs are included in their original labelling. Without -k, only one member of each nontrivial isomorphism class is written, with canonical labelling. 🦋
• -fxxx — specify a partition of the vertex set. xxx is any string of ASCII characters except nul. This string is considered extended to infinity on the right with the character 'z'. The sequence 'x^N', where x is a character and N is a number, is equivalent to writing 'x' N times. One character is associated with each vertex, in the order given. The labelling used obeys these rules:
  1. the new order of the vertices is such that the associated characters are in ASCII ascending order
  2. if two graphs are labelled using the same string xxx, the output graphs are identical iff there is an associated-character-preserving isomorphism between them.

If a leading - is used, as in -f-xxx, the characters are assigned to the vertices starting at the last vertex, and the new order of the vertices respects decreasing ASCII order. 🔄

• -i# — select an invariant (1 = twopaths, 2 = adjtriang(K), 3 = triples, 4 = quadruples, 5 = celltrips, 6 = cellquads, 7 = cellquins, 8 = distances(K), 9 = indsets(K), 10 = cliques(K), 11 = cellcliq(K), 12 = cellind(K), 13 = adjacencies, 14 = cellfano, 15 = cellfano2, 16 = refinvar(K)) 🌈
• -I#:# — select mininvarlevel and maxinvarlevel (default 1:1) 🎯
• -K# — select invararg (default 3) 🎯
• -u — write no output, just report how many graphs it would have output. In this case, outfile is not permitted. 💀
• -Tdir — specify that directory "dir" will be used for temporary disk space by the sort subprocess. The default is usually /tmp. 📁
• -Z# — specify memory for sorting (number followed by %, K, M, or G) 🧠
• -q — suppress auxiliary output 🤫

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okay real talk bestie: -k quietly makes -s, -g and -z do absolutely nothing, and -u means you don't get to name an outfile at all. read the fine print, it's iconic for a reason 🎀

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and that's the whole page, you ate that 💅 this was shortg 2.9.3, from September 2026, section 1 of the manual. go remove some isomorphs, bestie, you've got this 🫶✨🌸