How do you find the blunders in your large surveys?

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How do you find the blunders in your large surveys?

Postby reeffish1073 » Jan 8, 2014 5:31 pm

Been catching up on some data entry and cartography work lately and noticed after i added 5 surveys in and brought the line plot over to Illistrator that the line plot was seriously skewed out! There were two loop closures here too, so i went and untied the closures and still the line plot is skewed out. How would you look for the error? Make a test dat.file and start deleteing the last 5 surveys till the line plot aligns again. Have reverified data entry and all seems well. figured untieing the loop closures would correct. but its the old surveys that are skewed out too! Any thoughts or suggestions welcome.

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Re: How do you find the blunders in your large surveys?

Postby driggs » Jan 24, 2014 11:08 am

If using Compass, I'd first check out its built-in support for identifying blundered loops and shots. I'd also ensure I was using a recent version of the software, and make sure my Survey Editor was configured to warn on backsight* errors greater than 2°.

If this still doesn't help, you may be in for a long evening of paging through stacks of mud-caked survey notes trying to tell a "1" from a "7", identifying missing or misplaced decimals or negative signs, looking for sketches that don't match the computer lineplot (did the book person accidentally flip back and frontsights, were they dyslexic when recording numbers)?

See also this list of potential cave survey blunders by Bob Hoke and Pat Kambesis, many of which you'll unfortunately be helpless in correcting without sending a team back underground.

* ... if you aren't doing backsights, your survey is probably a work of fiction anyway. Keep draftin'!
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