MCXDIAMETER(1)

💖 mcx diameter(1) 💖

okay so bestie, welcome to the mcx diameter manual page, USER COMMANDS edition ✨ this is the one that measures how stretched out your graph is, and honestly? it's giving main character energy.

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🌸 NAME 🌸

mcx_diameter — compute the diameter of a graph 🦋

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✨ SYNOPSIS ✨

mcx diameter [options]

okay so real talk, mcxdiameter is not actually a program, no cap. this page is just documenting what the mcx program does when you invoke it in diameter mode. 💅

and btw, these options are accessible in all mcx modes: -h, --apropos, --version, -set, --nop, -progress <num>. they get described over in the mcx manual page, iykyk.

mcx diameter [-abc <fname> (specify label input)] [-imx <fname> (specify
matrix input)] [-o <fname> (output file name)] [-tab <fname> (use tab
file)] [-t <int> (use <int> threads)] [-J <intJ> (a total of <intJ> jobs
are used)] [-j <intj> (this job has index <intj>)] [--summary (output
diameter and average shortest path length)] [--list (list eccentricity
for all nodes)] [-h (print synopsis, exit)] [--apropos (print synopsis,
exit)] [--version (print version, exit)]

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🎀 DESCRIPTION 🎀

mcx diameter computes the diameter of a graph. periodt. 💅

okay so here's the tea: your input graph should be symmetric. if it's a directed graph, the results will be unpredictable 😭 — like, genuinely, we do not know what you'll get. but for label input this is literally irrelevant, because mcx diameter will just build a symmetric graph out of your input anyway. iconic behaviour fr fr. 🦋

if you specify your input graph/matrix with the -imx option, it has to be in mcl matrix/graph format. you can also use label input instead with the -abc option. for a description of these two input formats, go peek at mcxio(5) 📖

by default, mcx diameter reads from STDIN and expects matrix format. and if you wanna specify label input from STDIN, use -abc - ✨

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💅 OPTIONS 💅

• -abc <fname> — (label input) the file name for input that's in label format. 🎀
• -imx <fname> — (input matrix) the file name for input that's in mcl native matrix format. 🦋
• -o <fname> — (output file name) the name of the file to write output to. 💖
• -tab <fname> — (use tab file) this one makes the output print with the labels found in the tab file. and with -abc, it'll additionally construct a graph only on the labels found in the tab file. if you use this option together with -imx, the tab domain and the matrix domain are required to be identical. no wiggle room, bestie. 🙈
• -t <int> — (use <int> threads)
• -J <intJ> — (a total of <intJ> jobs are used)
• -j <intj> — (this job has index <intj>)

so, computing the diameter of a graph is time-intensive for large graphs 😮‍💨 if you've got multiple CPUs available, consider using as many threads as you can. and on top of that, you can spread the computation over multiple jobs/machines. these three options are described in the clmprotocols manual page. 📚

the following set of options, if given to as many commands, defines three jobs, each running four threads:

-t 4 -J 3 -j 0 -o out.0
-t 4 -J 3 -j 1 -o out.1
-t 4 -J 3 -j 2 -o out.2

and then you can collect that output with:

mcx collect --add-column -o out.all out.[0-2]

• --list — (list eccentricity for all nodes)
• --summary — (output diameter and average eccentricity)

the default mode is --list, which results in output of the eccentricity of all nodes. so like, the eccentricity of a node is the distance to any node that is the furthest away from it. and the diameter of a graph is the maximum of the eccentricity taken over all nodes in a graph. 👑

heads up bestie: in this mode, mcx diameter will not output the diameter itself. if you want just the diameter and the average eccentricity, use --summary. 💅

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🌈 SEE ALSO 🌈

mcxio(5), and mclfamily(7) for an overview of all the documentation and the utilities in the mcl family. 🫶

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and that's the whole vibe, bestie!! 💖 this page is from mcx diameter 22-282, dated 9 Oct 2022. go forth and measure some diameters, you've absolutely got this. periodt. ✨🎀🦋💅