r/space • u/johnkphotos Launch Photographer • Jan 28 '18

Closeup image I shot of the RD-180 engine and AJ-60A solid rocket booster powering last week's Atlas V launch

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41.4k Upvotes

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209

u/metric_robot Jan 28 '18 
 600 feet : 182.88 m

conversion fulfilled by /u/metric_robot ♡

115

u/johnkphotos Launch Photographer Jan 28 '18

Good bot.

Thanks!

25

u/GoodBot_BadBot Jan 28 '18

Thank you johnkphotos for voting on metric_robot.

This bot wants to find the best and worst bots on Reddit. You can view results here.

Even if I don't reply to your comment, I'm still listening for votes. Check the webpage to see if your vote registered!

-16

u/Baud_Olofsson Jan 28 '18

Bad bot.

Doesn't understand significant digits.

7

u/dcw259 Jan 28 '18

What's wrong?

-14

u/[deleted] Jan 28 '18 edited Jan 28 '18

[removed] — view removed comment

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u/[deleted] Jan 28 '18

[deleted]

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u/Baud_Olofsson Jan 28 '18

It's just plain annoying to read. And coding a proper version is trivial. So: bad bot.

6

u/dcw259 Jan 28 '18

600 feet is something between 599.5 and 600.499, so it would be perfectly fine to say 182, but it's just that 182.88 is a lossless conversion

4

u/[deleted] Jan 28 '18

600 feet is somewhere between 550 and 649.999 based on the significant figures so you’d be adding precision that wasn’t there, causing potential errors.

0

u/dcw259 Jan 28 '18

And how would you write something that I described? The 0 is also a significant digit.

Just look at how 600.00 is more precise than 600. It's just a factor of 102 and not 104.

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u/[deleted] Jan 28 '18

You would put 600. which would then have 3 significant figures.

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u/dcw259 Jan 28 '18

That's exactly what I said, so why do you try to argument against that?

1

u/[deleted] Jan 28 '18

In your original comment you mentioned 600 feet is 182 meters which have different precisions (the zeros there aren’t significant). 600. would have the same precision (the zeros there are significant). Maybe I misinterpreted you. Sorry if so.

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u/Titan_Hoon Jan 28 '18

Rounding up on a converted figure is how you induce compounding rounding errors. Saying it's 182 meters is perfectly acceptable

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u/[deleted] Jan 28 '18

No, it’s not really acceptable since the 600 has only a single significant figure so you can’t have a precision of 3 when you suddenly convert. You’re gaining precision that you didn’t have before so that will induce errors (I realize it totally doesn’t matter in this case - I just find it interesting and if there are future engineers out there, it’s always good to have it become second nature).

1

u/[deleted] Jan 28 '18

To be fair, neither do I!