FV(1)

✨ FV(1) — the FITS file viewer/editor that lives in your terminal-adjacent heart ✨

okay so bestie, welcome to the fv manual page (that's "User Commands", section 1, for the record 💅) — and no cap, this little icon is about to become your main character.

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🎀 NAME 🎀

fv — a tool for viewing and editing FITS format files. yes, FITS. the astronomy file format. we're doing science today, bestie 🌌

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🌸 SYNOPSIS 🌸

fv

that's it. that's the whole synopsis. iconic, honestly.

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🦋 DESCRIPTION 🦋

fv is a FITS file viewer and editor developed at the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA / GSFC. NASA. literally NASA made this. we're using NASA software to look at space pictures and honestly? that's the vibe 🚀✨

To start up fv on Unix workstations, enter fv in a command window. that's the whole thing. you just type it and go.

you can optionally append the name of a FITS file, or multiple files, to be opened. so like:

• fv ngc1316o.fit — opens a single file, one (1) galaxy, we love to see it 🌀
• fv ngc* — opens all the FITS files in the current directory whose name matches the string. glob city. the whole neighborhood. we stan a wildcard 💖

On Windows PCs you can start fv either by double clicking on the fv desktop icon, or by dragging a FITS file from, say, Windows Explorer onto the fv icon. drag and drop, the original "slay" 💅

It is also possible to set up your Windows or Unix environment so that you can just double click (in the File Manager or on an e-mail attachment) on a FITS file that has a standard extension like .fit or .fits and then have fv automatically start up and open that file. so you click the file, fv wakes up, opens it, no thoughts, just vibes 🫶

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✨ OPTIONS ✨

• -cmap m — Set the colormap. and bestie, there are layers to this one:
  • m=0 — Default behavior. I.e. choose the "best" colormap. it just... knows. trust it 👑
  • m=1 — Force POW to setup a new private pseudocolor colormap (very safe). very safe!! the manpage said it, not me 💚
  • m=2 — Force POW to use truecolor mode (very safe, but looks bad on low color displays and runs slower than pseudocolor). Note: this will cause powSetupColormap to look for a truecolor visual; if it can't find one, it will allow the main Tk code to pick a visual, but POW will still use "truecolor mode" (i.e. the Tk photo widget) to display images. so like... it's safe, but it's giving "graphics card from 2004" 😭
  • m=3 — Force use of the screen default colormap. This should be reasonably safe now, but often won't be what you want. "reasonably safe" is doing a lot of heavy lifting in that sentence bestie 🙈
• -winmanager 1/0 — Turn Window manager On and Off. 1 = on, 0 = off. binary queen 🌈
• -quiet — Startup fv without open dialog and stay open even if all files are closed. no pop-ups, no closing on you. loyal fr fr 💜
• -module modName or -modName — Load a web module into fv. two ways to say the same thing, because options deserve range ✨
• -version — Display fv Version. know your version. respect your version 🎀
• -user — Logon with user ID. hi, it's me, your user ID 👋

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🌈 ENVIRONMENT 🌈

The environment variable FVTMP defines what directory fv will use to create temporary files. so if you ever need to tell fv where to make its little temp mess, that's the variable. set it, love it, keep your /tmp tidy 🧚

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💖 AUTHOR 💖

Text copied from heasoft's web page at https://heasarc.gsfc.nasa.gov/docs/software/lheasoft/ftools/fv/doc/startFv.html

(crediting your sources is a whole personality trait and honestly it's hot ⭐)

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🔥 SEE ALSO 🔥

The program is documented fully by the online help that can be accessed from the built-in help viewer. so when in doubt, open the help viewer inside fv — the full tea is in there, iykyk 🍓

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reminder bestie: FITS files are real data, so play nice, and if a colormap "should be reasonably safe" maybe don't make it your whole personality 💀

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and that's the page!! brought to you by Heasoft, dated July 2009 — yes she's a vintage icon and she still serves 👑✨ thanks for reading, go open a .fits file, mwah 💋