MARCHIVELIST(1)

💫 MARCHIVELIST(1) 💫

okay bestie, so this is mArchiveList from the Montage era — a whole manual page, and yes I read the whole thing so you don't have to. buckle up 🎀

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✨ NAME ✨

mArchiveList — grab yourself a whole list of archive images from the IRSA server. it's giving personal shopper but for sky data 💅

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🌸 SYNOPSIS 🌸

mArchiveList survey band object|location width height outfile

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🦋 DESCRIPTION 🦋

so basically? you hand it a spot on the sky, an archive name, and a size in degrees, and it goes and talks to the IRSA server and comes back with a list of archive images. that list has everything you need in it so that mArchiveGet can do the actual downloading. match made in heaven fr fr 💖

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👑 ARGUMENTS 👑

• survey — pick one, bestie, from this lil lineup:
  • 2MASS
  • DSS
  • SDSS
  • DPOSS
• band — case insensitive, so don't stress about caps 🫶 your options are:
  • (2MASS) j, h, k
  • (SDSS) u, g, r, i, z
  • (DPOSS) f, j, n
  • (DSS) DSS1, DSS1R, DSS1B, DSS2, DSS2B, DSS2R, DSS2IR
• object|location — either an object name or a coordinate string, and NED is the one who resolves it for you. ⚠️ tiny but crucial: if your string has spaces in it, you must wrap it in double quotes.
• width — how wide your area of interest is, in degrees.
• height — how tall your area of interest is, in degrees.
• outfile — the path to the output table. where the magic lands. ✨

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🌈 RESULT 🌈

[struct stat="OK", count=num-images]

outfile is an ASCII table stuffed with image metadata for whatever region and survey you asked about. and the last column of that table? it's a URL that mArchiveGet can use to fetch the image. no cap, that's the good stuff 🔥

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💀 MESSAGES 💀

• OK — [struct stat="OK", count=num-files]
• ERROR — Can't open output file outfile
• ERROR — Error message from IRSA's ImgList service
• ERROR — Couldn't find host hostname
• ERROR — Couldn't create socket()
• ERROR — hostname: connect failed

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🍓 EXAMPLES 🍓

wanna pull metadata and file handles for 2MASS J-band images covering a half-degree by half-degree area around m31? say less:

mArchiveList 2mass j m31 0.5 0.5 2mass_m31_j.tbl
       [struct stat="OK", count=18]

output file: 2mass_m31_j.tbl.

and if you're after GPFS file handles for SDSS u-band images:

mArchiveList -s gpfs sdss u m101 0.2 0.2 sdss_m101_u.tbl
       [struct stat="OK", count=16]

output file: sdss_m101_u.tbl.

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🙈 BUGS 🙈

okay so this is the part where we keep it real, because these are actual caveats and you need to know them:

• the drizzle algorithm has been implemented but has not been tested in this release. it's giving "shipped it, haven't looked at it" 😭
• if a header template contains carriage returns (like, if it was created or modified on a Windows machine), the cfitsio library will be unable to read it properly, and you'll get this error: [struct stat="ERROR", status=207, msg="illegal character in keyword"]. so yeah, watch out for that.
• for the background correction algorithms, it's best if the area described in the header template completely encloses all of the input images in their entirety. if parts of input images get "chopped off" by the header template, the background correction will be affected. so the recommendation is: use an expanded header for the reprojection and background modeling steps, and then go back to the originally desired header size for the final coaddition. also, the default background matching assumes there are no non-linear background variations in the individual images (and therefore in the overlap differences). if you're at all uncertain about that, it's safer to turn on the "level only" background matching — that's the -l flag in mBgModel.

no gatekeeping here, just telling you what the page says. 🫶

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💜 COPYRIGHT 💜

2001-2015 California Institute of Technology, Pasadena, California

if your research uses Montage, please include this acknowledgement, word for word: "This research made use of Montage. It is funded by the National Science Foundation under Grant Number ACI-1440620, and was previously funded by the National Aeronautics and Space Administration's Earth Science Technology Office, Computation Technologies Project, under Cooperative Agreement Number NCC5-626 between NASA and the California Institute of Technology."

also, the Montage distribution includes an adaptation of the MOPEX algorithm developed at the Spitzer Science Center. iconic behavior honestly 👑

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and that's the whole page, bestie 💅 this was Montage 5, dated Dec 2016 — go forth and list some archives, you absolute main character 🌟💖