XYCPT(1)

💖 XYCPT(1) — the girlies' guide to xycpt 💖

sooo this is the User commands page for xycpt, bestie. It lives in the cptutils fam (v1.82, if you're keeping score 🎀). Let's get into it.

---

✨ NAME ✨

xycpt — generate GMT colour palette table (cpt) files from column data. yes literally that's the whole job and she does it flawlessly 🦋

---

🌸 SYNOPSIS 🌸

xycpt [-b rgb] [-d] [-f rgb] [-h] [-n rgb] [-o path] [-r registration]
      [-u] [-v] [-V] [-4] [-5] [-6] [path]

---

💅 DESCRIPTION 💅

okay so xycpt makes discrete or continuous cpt files out of the simplest possible input — like, just some sample values describing your colour (or greyscale) range, and she takes it from there. main character energy tbh 👑

Your input is 1–4 columns, and the way she reads them is very specific, so listen up:

• With 2 or 4 columns, that first column gets interpreted as a (double) z value. 🍓
• With 1 or 3 columns, the z value is taken implicitly — she just knows.
• With 1 or 2 columns, the final column is taken as a greyscale value.
• With 3 or 4 columns, the last 3 columns are taken as RGB values. 🌈

And the I/O vibe? She reads from stdin if you don't hand her a file as the final argument, and she writes to stdout if you don't specify the --output option. no cap 💖

---

✨ OPTIONS ✨

quick heads up before we dive in: in all of the rgb specs below, the format is always red/green/blue, where each colour component is an integer in the range 0 to 255. got it? good. slay. 💅

• -b, --background rgb — sets the background colour of the output.
• --backtrace-file path — pick a file for her to write a formatted backtrace into. 🫶 heads up tho: the file only gets created if a backtrace actually happens, which is typically when an error occurs.
• --backtrace-format format — sets the format of the backtrace written to whatever file you gave to --backtrace-file. Your choices are plain, xml or json.
• --comments-generate — makes a comment in the output file with summary data (the date of creation, plus the name and version of the cptutils package). cute, informative, iconic ✨
• --comments-read path — reads the comments from path and adds them to the output gradient. the format is just a plain text multi-line document with no comment delimiters — she'll add those herself, don't worry 💖
• -d, --discrete — output a discrete cpt file. (the default is continuous, fyi.)
• -f, --foreground rgb — sets the foreground colour of the output.
• -h, --help — brief help. short king behavior 😌
• -n, --nan rgb — sets the NaN (no data) colour of the output.
• -o, --output path — write the output to path instead of stdout.
• -r, --registration string — for discrete conversion (so, when you're using --discrete), this specifies upper, middle or lower registration of the data value. For the upper and lower types, the final (respectively the first) colour is omitted from the output — only the z value gets used. For middle registration, all the colours appear in the output. 🌸
• -u, --unit — colour values get specified as floating point numbers in the range 0–1 instead of as integers in the range 0–255.
• -v, --verbose — verbose operation. she'll tell you everything 🗣️
• -V, --version — version information.
• -4, --gmt4 — use GMT 4 conventions when writing the cpt output: the colour-model code is uppercase, and the colours are separated by spaces.

⚠️ This is incompatible with the -5 and -6 options of course.

At present this option is the default, but that will change at some point. So if your use of the output depends on the GMT 4 layout (like, it's being consumed by a custom parser, for example), specify this option explicitly. fr fr, don't get caught out. 💀

• -5, --gmt5 — use GMT 5 conventions when writing the cpt output: the colour-model code is lowercase, and the colours are separated by a solidus for RGB and CMYK, and by a dash for HSV.

⚠️ This is incompatible with the -4 and -6 options of course.

• -6, --gmt6 — as the -5 option, but this one allows the HARD_HINGE and SOFT_HINGE directives in place of the explicit HINGE = directive. 🔥

⚠️ This is incompatible with the -4 and -5 options of course.

---

🎀 AUTHOR 🎀

J.J. Green — we stan 👑

---

and that's the whole page bestie!! this gorgeous thing comes from cptutils version 1.82, dated 9 July 2024 — so yeah, she's giving current, she's giving maintained, she's giving everything. now go make some cpt files, you absolute icon 💖✨🦋🌸💅🫶👑🌈⭐