# What is the exact meaning of "to calculate under the carpet"? **URL:** \ **Category:** Factual Questions\ **Created:** [November 7, 2014, 10:00am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965 "2014-11-07T10:00:34Z")\ **Posts on this page:** 16\ **Page:** 2
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 9, 2014, 11:18am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/21 "2014-11-09T11:18:53Z")
A thought just occurred to me when it comes to neologisms/newly coined phrases/variations of well-worn phrases and idioms, and it’s this:When is it proper use them? How much time should be given to neologisms before it’s proper to use them? It’s personal taste, but also a question of common sense think. An earlier phrase like " fall culpable to" seems like an illogical construction, which is why I avoid it. Yet it is being used. I’d like some of your opinion on that subject. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [November 9, 2014, 11:52am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/22 "2014-11-09T11:52:47Z")
All of these sorts of phrases, idioms, etc should probably only be used as a light garnish to speech. If you use too many, there is a risk of mixed metaphor, or just sounding superficial and buzzwordy. ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [November 9, 2014, 9:59pm UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/23 "2014-11-09T21:59:35Z")
If you like a turn of phrase and think it makes obvious sense, use it. If you see it enough that you think people will recognize the meaning, use it. If you think it sounds stupid and makes the user an ass, don’t use it. If it is confusing and you have to ask someone what it means, you might not want to use it. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 9, 2014, 11:22pm UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/24 "2014-11-09T23:22:32Z")
Thanks Mangetout and Irishman. But it seems to me that some writers write perhaps to be read by other writers and often (it seems to me) target a certain audience (high-brow writers). Having read many Christopher Hitchens essays, there is no doubt that he was one of the most original writers of the post-WWII generation. I don’t think I’m going to question his use of English, even if some of his phrasing seems dated or just very unique. I probably won’t repeat some of them, because they wouldn’t work very well in my hands. Then there are the low-brow columns of the New York Post or Huffington Post. It’s English, but if I see a phrase I’m not familiar with, it’s probably because I’m not familiar with a certain type of environment that uses those types of phrases on a daily basis, or it’s could be sloppy writing. I’m inclined to believe that more often than not, it’s the latter case. ---
**Author:** ![missred](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/missred/32/14096_2.png) [@missred](https://boards.straightdope.com/u/missred)\ **Post date:** [November 10, 2014, 12:50am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/25 "2014-11-10T00:50:12Z")
Perhaps to calculate under the carpet is meant to take into consideration the unknown “sweepings” into one’s calculations. ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [November 10, 2014, 1:11am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/26 "2014-11-10T01:11:57Z")
[QUOTE=M.R. O’Donohoe] “Before making this powerful simplification, we consider some implications of the use of floating-point arithmetic which will be swept under the carpet in so doing. These points often cause problems for the software designer rather than the numerical analyst” [/QUOTE] I’ve never seen “calculate under the carpet” ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [November 10, 2014, 1:48am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/27 "2014-11-10T01:48:46Z")
> [@davidmich](#): > > … Having read many Christopher Hitchens essays, there is no doubt that he was one of the most original writers of the post-WWII generation. I don’t think I’m going to question his use of English, even if some of his phrasing seems dated or just very unique. I probably won’t repeat some of them, because they wouldn’t work very well in my hands. Then there are the low-brow columns of the New York Post or Huffington Post. It’s English, but if I see a phrase I’m not familiar with, it’s probably because I’m not familiar with a certain type of environment that uses those types of phrases on a daily basis, or it’s could be sloppy writing. I’m inclined to believe that more often than not, it’s the latter case. Those are both situations to avoid those turns of phrase. Either you’re not comfortable using it, or you aren’t familiar with it and can’t be sure it’s a common expression. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 10, 2014, 7:50am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/28 "2014-11-10T07:50:40Z")
Originally Posted by M.R. O’Donohoe “Before making this powerful simplification, we consider some implications of the use of floating-point arithmetic which will be swept under the carpet in so doing. These points often cause problems for the software designer rather than the numerical analyst” Where is the above from? I couldn’t find it online. Perhaps Melbourne,you can give me link to the above quote. " floating-point arithmetic which will be swept under the carpet " I hadn’t come across this before. Is it possible that what I read is some derivation of the above usage? So is it as Mangetout suggests “creative accounting” or as missred suggests “unknown sweepings” ---
**Author:** ![Wendell\_Wagner](https://avatars.discourse-cdn.com/v4/letter/w/8491ac/32.png) [@Wendell\_Wagner](https://boards.straightdope.com/u/Wendell_Wagner)\ **Post date:** [November 10, 2014, 8:47am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/29 "2014-11-10T08:47:23Z")
No, this is just another use of the term “sweep under the carpet.” What the passage is saying is that there are some interesting/odd/weird/disturbing/stupid (or whatever) implications of using floating-point arithmetic. The author says that they will deliberately ignore these implications because they would be too complicated to explain or because explaining them would show that the use of floating-point arithmetic might invalidate the calculations. The author will therefore ignore these implications in order to get through their explanation of the subject without complicating what’s being written. They are thus “sweeping under the carpet” the implications. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 10, 2014, 9:48am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/30 "2014-11-10T09:48:37Z")
That’s it! Thanks Wendell Wagner. I’m pretty sure that’s how the author I read meant to use the phrase “calculate under the carpet”; to sweep away anything that would invalidate a calculation. I remember reading Peter Ackroyd’s biography of Isaac Newton and talking about Newton not being above fudging his calculations, but I don’t thing I read it there. I’ll have another look. ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [November 10, 2014, 12:46pm UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/31 "2014-11-10T12:46:17Z")
> [@davidmich](#): > > Originally Posted by M.R. O’Donohoe > “Before making this powerful simplification, we consider some implications of the use of floating-point arithmetic which will be swept under the carpet in so doing. These points often cause problems for the software designer rather than the numerical analyst” > Where is the above from? I couldn’t find it online. Perhaps Melbourne,you can give me link to the above quote. > " floating-point arithmetic which will be swept under the carpet " > I hadn’t come across this before. Is it possible that what I read is some derivation of the above usage? > > So is it as Mangetout suggests “creative accounting” or as missred suggests “unknown sweepings” I found it here [Numerical Analysis | PDF | Numerical Analysis | Matrix (Mathematics)](http://www.scribd.com/doc/171225976/Numerical-Analysis) but it is a PDF and requires registration so I did not read it. ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 10, 2014, 1:16pm UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/32 "2014-11-10T13:16:39Z")
Thanks Bob++. Thank you all. Very helpful davidmich ---
**Author:** ![davidmich](https://avatars.discourse-cdn.com/v4/letter/d/e56c9b/32.png) [@davidmich](https://boards.straightdope.com/u/davidmich)\ **Post date:** [November 10, 2014, 2:01pm UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/33 "2014-11-10T14:01:55Z")
In case you’re interested I just looked up Ackroyd’s biography. The phrase isn’t there. p. 85 “He was not averse, however, to fudging or doctoring figures so that he might pretend to a higher degree of accuracy than he had actually accomplished” ---
**Author:** ![GrumpyBunny](https://avatars.discourse-cdn.com/v4/letter/g/bc8723/32.png) [@GrumpyBunny](https://boards.straightdope.com/u/GrumpyBunny)\ **Post date:** [November 10, 2014, 4:27pm UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/34 "2014-11-10T16:27:49Z")
Perhaps you mean a back-of-the-envelope calculation? I’ve never heard the phrase “to calculate under the carpet”. This sounds like a malapropism that happened during a home improvement project. 🙂 Edit: NM – I should read the entire thread before responding. Interesting usage by the author. ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [November 12, 2014, 2:15am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/35 "2014-11-12T02:15:00Z")
> [@Melbourne](#): > > I’ve never seen “calculate under the carpet” M.R. O’Donohoe quotation is from [Numerical Analysis I]([people.ds.cam.ac.uk/nmm1/arithmetic/na1.pdf](http://people.ds.cam.ac.uk/nmm1/arithmetic/na1.pdf) ‎) ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [November 12, 2014, 5:01am UTC](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965/36 "2014-11-12T05:01:53Z")
> [@Wendell\_Wagner](#): > > What the passage is saying is that there are some interesting/odd/weird/disturbing/stupid (or whatever) implications of using floating-point arithmetic. The author says that they will deliberately ignore these implications because they would be too complicated to explain or because explaining them would show that the use of floating-point arithmetic might invalidate the calculations. The author will therefore ignore these implications in order to get through their explanation of the subject without complicating what’s being written. They are thus “sweeping under the carpet” the implications. Close: he is using “swept under the carpet” in standard usage. But what he’s saying is that he intends to make a simplification, but the simplification he is going to make will gloss over some aspects of floating point arithmetic. So he will first list those implications. Typically in science, when engineers/etc make simplifications, they have to be aware of what those simplifications overlook or exclude. In other words, what are the conditions that the simplifications are valid? Like when it it acceptable to use Newtonian physics versus Relativity? (Actually, we usually learn it the other way around - when is it required to use Relativity because Newtonian physics is inadequate?) What O’Donohoe is doing is creating a simplification, but he is listing explicitly the complications that will be neglected by using that simplification for his analyses. His justification is that the complications affect the software designer, and his discussion is for the numerical analyst, who won’t see those problems. [Previous page](https://boards.straightdope.com/t/what-is-the-exact-meaning-of-to-calculate-under-the-carpet/703965.md?page=1)