GML2GV,GV2GML(1)

💖 GML2GV,GV2GML 💖

okay bestie, sit down, hydrate, because today we're talking about a two-for-one situation: gml2gv and gv2gml, the GML-DOT converters, both living in section 1 of the manual (that's General Commands Manual energy, iykyk). two icons, one page, no notes. 🎀

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✨ SYNOPSIS ✨

gml2gv [ -?v ] [ -ggname ] [ -ooutfile ] [ files ]
gv2gml [ -y ] [ -?  ] [ -ooutfile ] [ files ]

look at them. so tidy. so slay. 💅

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🦋 DESCRIPTION 🦋

so here's the tea, bestie:

• gml2gv takes a graph that's written in the GML format and converts it into a graph in the GV format — and yes, GV is the thing that used to be called DOT, the glow-up was real. ⭐
• gv2gml goes the other way around: it takes a graph in the GV format and hands you back a graph in the GML format. 🔁

it's giving translator besties. one speaks GML, one speaks GV, they're each other's duolingo streak. 🦉

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👑 OPTIONS 👑

The following options are supported (and yes, we're going through every single one, no skipping, that's the rule 💖):

• -v — turns on verbose mode. it will simply talk to you more. main character behavior honestly. 🗣️
• -y — uses attributes according to yWorks.com documentation instead of the GML specification. so like, a different rulebook for the attributes. pick your canon, bestie. 📚
• -? — prints usage information and then exits. it's the "what do you want from me" flag. 🙈
• -ggname — the string gname gets used as the name of the generated graph. and if multiple graphs get generated, the subsequent graphs use the name gname appended with an integer. so gname, then gname + a number, then another number, etc. cute little sequel naming convention, very franchise of them. 🔢
• -ooutfile — prints output to the file outfile. and if you don't give it one? gml2gv uses stdout. so it just yells into your terminal, as nature intended. 📢

🌸 OPERANDS 🌸

The following operand is supported:

• files — names of files containing 1 or more graphs in GML. and if you don't specify any files operand at all, the standard input will be used. so you can just pipe it in like the tech-savvy legend you are. 🫶

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🎀 RETURN CODES 🎀

• returns 0 if there were no problems during conversion ✨
• returns non-zero if any error occurred 💀

so like, 0 = good vibes, anything else = the vibe check failed. 😭

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💀 LIMITATIONS 💀

okay this is the part where we get real, bestie, because the manual is about to humble us:

• the graph and graphics models of GV and GML differ significantly, so the conversion is at best approximate. it's not a perfect match, it's a vibe-based approximation. 🫠
• in particular, it is not clear how multiedges are differentiated in GML, so multiedges are created in GV with no user-available key. that's just how it is, no cap.
• also, no attribute information is lost, in that any GML attributes that aren't converted to GV equivalents are retained as attributes in the output graph. nothing gets ghosted here, everything is kept. 🥰
• at present, gv2gml does not support subgraphs and clusters. nope. not supported. don't ask. 🚫
• in addition, there does not appear to be a standard mechanism for specifying default node and edge attributes in GML, so any attributes are repeated for every node and edge. yeah. every single one. it's verbose like that. 😮‍💨

no fr, remember: this conversion is approximate, gv2gml has no subgraph/cluster support, and multiedges come out of GML with no user-available key in GV. the manual said it, so we said it. 🫡

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💜 AUTHORS 💜

• Emden R. Gansner <erg@research.att.com> — the icon, the moment, the legend who wrote this. 👑

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🌈 SEE ALSO 🌈

• dot(1)
• libcgraph(3)

go read those next, bestie, that's the homework. 📖✨

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and that's the whole page! 💅 this was GML2GV,GV2GML(1) from the General Commands Manual, dated 24 June 2011 — yes, that's the source/version-and-date sign-off, we're closing it out with a lil curtsy 🎀. mwah, go convert some graphs, you've got this. 💖🦋🌸