recognizing the motif

Question: I encounter the term motif in composition books, and still have no idea what a motif is. Many sources (including some dictionaries) try to define it as "prominent sequence of notes" or "basic theme of a melody", or even "repeatable part".
But hey, after all both brick and window are fundamental elements of a house. So, which one is the building block? Both?
I mean, motif and measure and theme and melody are all considered building block of a piece of music. So, how do we can differentiate them?
Comment: Have you read the article in Wikipedia at https://en.wikipedia.org/wiki/Motif_(music)? It has sound files that you can listen to.
Answer: A motif could be a melodic or rhythmic fragment. We're not talking about semantic building blocks like meter or harmonic language, but musical building blocks. The immortal example of a large-scale piece built off of a prominent motif is Beethoven's Symphony No. 5 in C Minor.

The first four notes are the rhythmic and melodic motif, which is used compositionally in transposition, inversion, and variation through the entirety of this first movement.
Comment: For any unique piece of music, most musicians familiar with structural analysis of music will come to the same conclusion. There are plenty of pieces with no recognizable motif whatsoever, but it's a common occurrence in many classical styles. The "rules," like many things in music, are not well-defined; but if you can identify a musical snippet that is self-contained enough to be an _idea_, and then analyze how that idea is elaborated upon in the remainder of the piece, you're probably safe calling that idea a motif.
Comment: Also fun is [New Horizons in Music Appreciation](http://www.youtube.com/watch?v=f0vHpeUO5mw).
Comment: So, if you give 10 composers a unique song, and ask them to specify motif, do they all come to the same answer? I mean, is motif recognition is composer based, or is it robust enough to have rules and formulas to be found? :)
Answer: Another use of a motif is as a "Leitmotif" ("leading motif") in an opera, associated with a character, thing or idea.  It can be long enough to be considered a "theme" but usually it is shorter; sometimes only a few notes or a single chord.  Sometimes it is only played once at a time, but sometimes layered on itself or on other music in complex ways.
Some composers of music for animated cartoons used leitmotifs.  Carl Stalling did the play-it-once thing in Bugs Bunny cartoons, quoting well-known pieces of music:  "Powerhouse" for a factory, "The Lady in Red" when Bugs Bunny dressed up as a woman, etc.
The first Popeye cartoon had an original song, "Popeye the Sailor Man".  The theme was used as a motif in all of the rest of the Popeye cartoons.  At the beginning it might be heard in a jaunty rhythm as Popeye walks down the street.  When he eats spinach, it is played fast and loud by a trio of trumpets, and then during the resolution it becomes a heroic march.  This is based directly on techniques pioneered by von Weber, Wagner, and especially Liszt.
Answer: A "motif" is a basic sequence of rhythm and/or melody that is used as the "building block" to a "theme", which is a larger overarching musical idea.
NReilingh's example of the first movement of Beethoven's 5th is an excellent example of the use of a motif to create a theme. The four-note motif is an identifiable repeating block within the "theme" that is Beethoven's 5th.
Here's another example, a personal favorite of mine (EDIT: replacing a dead link):
Comment: Still not clear to me. Still I have nothing to formulate a motif and differentiate it with theme. Motif is smaller than theme? How to determine? By length?
Comment: the link is dead

recognizing the motif


How do I deploy the personal ordnance drop?

Question: I've had the ordinance drop icon in Halo 4 infinity multiplayer on my screen (upper middle center). My question is what button do I press to select/deploy the ordinance drop? I can't find any help on this.
Answer: The ordnance drop is triggered by pressing a direction on your D-Pad.  Which direction you push depends on which of the 3 ordnance choices you'd like.  Left, down, and right represent different ordinances, as indicated by the icons in the top center of your HUD.
Answer: As agent 86 says, the left/down/right arrows on the D-Pad will select your drop. Bear in mind that not every drop is a power weapon, and will contain a selection of power weapons, grenades, overshield/speed boost and other weapons such as the needler.
The drop will land around where your gun recitle is pointing, so don't use it when zoomed in through a sniper rifle unless you want to donate your ordnance to the enemy. If you are out in the open the caniseter will be dropped by the Infinity (yes, it's possible to splatter enemies and destory vehicles with it) or if you're in cover such as caves, it will be teleported in.
There's also no need to call in the drop as soon as you get it - ordnance drops "roll over" after you die so if you see you have a sniper or binary rifle waiting for you, it might be an idea to wait until you die and then choose a loadout with Active Camo and the unlock that shows the motion tracker while zoomed in.
Answer: what agent86 and tombull89 say are true. but they're missing something. there is a tactical package you can unlock called "Requisition." it allows you to request your choice of ordnance drops. its useful in PVP but i dont know if it helps in spartan ops.
Answer: If the ordanance doesn't give you options you like, don't just use it to use it. Wait until your out of amo or in some cases don't have another gun


How would plants survive an extremely long, cold night

Question: On my planet, the whole day lasts nine years. The day lasts 4.5 years of incredible heat, with glaciers from the night providing water. The night starts with the sunset, during which violent tornadoes occur and enters into the night lasting four and a half years before another set of tornadoes and then the cycle restarts. Animals migrate to survive these conditions but plants cannot do this. Many plants other than trees just spread their seeds and die during the winter in the real world. How would annual plants such as trees and cacti survive tornadoes as well as four and a half years of darkness and cold?
Comment: Baobabs are an example of plant that can store water to last for years, and which can grow so massive that they can probably resist a tornado (though I have no evidence, even annedoctal, to support the part about resisting a tornado).
Comment: Not sure I understand why there would be that much turbulence, but the more I considered it one could come up with a scenario where the time of "day" would be roughly equivalent to a climactic zone. e.g. late afternoon would be desert, morning would be temperate spring. The temp wouldn't drop fast at sunset, because the ground would still be pretty hot. On earth it takes about 4 minutes for the sun to move through 1 degree of the sky, on your planet you are talking more like 9+ days for the same movement. Noon is going to be a moving hotspot.
Comment: @Seeds your are correct, that is how my concept of seasons work on this world. The reason there are tornadoes is because cold air from the night mixes with hot air from the day. This is how tornadoes are made
Answer: Most plants would rely on seeds, and would have multiple cycles during the 39,420 hours of daylight. The seeds would probably have some temperature sensitivity so as to not germinate just before dusk.
Other plants might have hardened cores, where most of the plant could go dormant and lose most of it's water to prevent cell rupture, while a small place in the center would stay alive.
Trees could grow very deep roots to store energy harvested during the long day time, and at night would use geothermal heat from deep underground to keep from freezing completely. Because trees grow slower, they might not depend on seeds, but instead sprout something like basal shoots, which would form into new trees, pulling energy and warmth from the parent until they can put down their own deep roots and become self sufficient.
One fun idea is a plant that "migrates". It likes a certain light level, and doesn't do well in bright sunlight or in darkness. It's area is in the higher latitudes where the sun is not directly overhead. It's a creeper and is constantly growing toward the best light, meaning that it's growth is mainly in one direction, following the sun. As it's old growth moves closer to dusk it dies off and rots, putting nutrients back into the soil for it to utilize the following day as the planet rotates back to the relative location of the plant.
Luckily for the plant, there are no large bodies of water at that latitude that might block it's path.
Answer: I'd like to point out that during that 4.5 year day these plants are going to have to keep growing, maybe even go thorugh multiple fertility phases, otherwise everyone would simply starve (imagine if all plants only produced fruit once in 4 years).
This implies that energy stored is consumed over time, so I'm not sure how much energy they will have available for the start of night.
That being said, here's some ideas:
Hybernation
These plants just store a lot of energy, then go into hybernation mode. They husband their resources, and many of them survive the long night.
Multiple Ways of Producing Energy
There are plants which thrive in darkness. Many plants on this planet might have evolved a sort of dual energy production system. One chlorophyll based, one similar to what mushrooms utilize, or maybe even carnivorous (eating insects, or small mammals).
Circle Of Life
Some plants may indeed die during the long night, yet leave their seeds behind to bloom when the sun comes up again. The tornadoes themselves may carry these seeds over from the day-side.
Perennials/Weird Energy Storage
Some plants may develop ways to store energy in massive underground root systems which they all draw power from (think of Avatar and the way in which all trees were connected).
Comment: Sorry, I should have been more clear, the whole day is 9 years. day and night included, I'll edit to make clearer. Great answer though, love the avatar idea
Comment: I edited it to reflect the correct numbers. Here's a question for ya though: how do seasons tie in with this day/night concept? Does the night bring with it very cold temperatures, or not?
Comment: The planet lacks an axial tilt, there are no seasons
Comment: That simplifies things then.
Comment: yeah, it came down to either doing complex climate maps with seasons I don't necessarily need or want. Or just not have seasons, the choice made itself
Comment: I'd love to know why I got a down-vote.
Comment: me to, your answer is definitively the best
Answer: From plants'perspective, that's not so different from Earth as it could seem.
In most climates in Earth, plants undergo periods of inactivity for several months a year, and in certain desert climates inactivity can even take years - until it rains. In those resting periods plants can remain in several forms: seeds, underground organs, or even the whole plant in a latency state. There is even a widely used classification of plant life forms based on how they deal with where buds remain in the disfavourable season.
The nine years cycle might be harder -colder, longer- than anything on Earth, but it's not very different from we have here, and some strategies that work for Earth plants (seeds?) are likely to work in the OP's planet.
Comment: Same for the plants near the polar caps.
Probably more so, since the dormant-making factor here is light/cold
Answer: My first thought was: It's Mushroom time!
Your photosynthetic plants would go through multiple cycles during the day, adapted for unrelenting sunlight. Trees and woody plants would have to hibernate, at night, and store enough to stay alive until the sun came back. The rest would just use seeds, and wait for light.
At night there would be fungus, and everything else that grows without light. Probably a lot that would be killed by light. There'd be lots of dead plants for them to use as nutrients. The woody plants of daytime would need some protection during the night, to keep from getting eaten.
Comment: ...and I forgot to indicate that annual type plants are ones that die every year, perennials are the ones that come back every year/more than once.
Comment: You know you can edit your answer right?
Comment: Fungi would'nt be able to do anything either in freezing temperatures, sorry
Answer: Annual plants could certainly make it with seeds that lie dormant during the "night", or winter. Sub-zero night temperatures can aid in prolonging seed viability while dormant. Even on Earth, plants like Lithops can produce seeds which remain viable for a few years without freezing.
At such a slow rotation , convection cells create strong winds which may also assist in seed dispersal. It's almost like tidal locking. Surface winds blow towards the bright side, so that each generation of seeds takes its part in the perpetual chase of the sun.
Migrating animals can easily migrate to the "twilight zone" and beyond. On their way, they eat fruits and disperse their seeds.
Perennial plants have different strategies:
1- blur the boundary between plant and animal. Give your plant the ability to move, and swim if necessary. After all, it's a SLOW rotation!
2- Remain active through the winter because oceans and atmosphere bring some heat to the other side. The atmosphere should be thick enough. They can harness wind power when light is absent: think of electrostatics due to wind friction.
3- Give them the ability to remain dormant if everything else fails. The plant starts to grow early. It has 4.5 Earth years to grow ans store enough sugars and minerals. When it's too cold, they hibernate.
Dealing with tornadoes: annuals can bend like grass. Perennials must store food in big roots and very short and stocky trunks. Barrel-cactus shape or even dome-shaped are best.


Seeking shapefile of hexagons that covers world?

Question: I'd like a persistent .shp that covers the world in hexagons (preferably of a decently small area)–does anybody know where I could find something like this, or perhaps what software I could use to make one? MMQGIS freezes whenever I try to export something of this size.
Comment: Could you specify how small "decently small" is? Also, what projection will you be using?
Comment: ArcGIS Users can use http://blogs.esri.com/esri/arcgis/2013/05/06/a-new-tool-for-creating-sampling-hexagons/ Create Hexagon Tessellation http://www.arcgis.com/home/item.html?id=03388990d3274160afe240ac54763e57
Comment: have you checked this https://www.arcgis.com/home/item.html?id=b073c9aa774649f6b8122631334b58f5#overview? I did not find how to download them as shapefile, but it maybe it is possible
Comment: also see https://gis.stackexchange.com/questions/310555/using-uber-h3-from-qgis
Answer: It's probably easiest for you to create your own hexagonal grid shapefile. Many GIS have built-in tools for creating hexagonal grids of any desired resolution and orientation. For example, in the cross-platform and open-source GIS Whitebox GAT, for which I am a developer, you can use the Create Hexagonal Vector Grid tool to create a hex-grid shapefile for the world using a countries shapefile as the base.

You can specify any desired resolution and whether the grid should be vertical or horizontal (a consideration when working with hex-tessellation). In fact, I enjoy working with hexagonal grids so much that I also wrote a tool for Whitebox GAT that performs hexagonal binning (like a hex heatmap). The following is an example for density of world cities:
Comment: Simple and brilliant!
Answer: Uber has recently developed H3, which is a geospatial indexing system using multiple hexagonal grids of different sizes organized hierarchically.
There is an R package called h3r that makes it easy to work with Uber's h3 in R. There are also Java and Java-script bindings of H3.
Answer: Note that it is impossible to partition a sphere into hexagons only; such a partition must contain some non-hexagonal cells. For example, every resolution of Uber's H3 contains exactly 12 pentagons amongst the hexagons.
You can generate .shp files of hexagonal global grids for all or part of the globe using the free software DGGRID ( http://www.discreteglobalgrids.org/software/ ). If you're an R user you can use dggridR ( https://github.com/r-barnes/dggridR ).
Answer: You can use QGIS to create hexagons, but I think Uber H3 is a better solution for most analysis. Here is a link to a tutorial for QGIS.
Comment: just to be clear, the tutorial is about how to create generic hex maps in Qgis, not how to use H3 hex grids in Qgis.


Yemenite Sefira

Question: What is the source for the custom that Yemenite Jews people count Sefira in Aramaic? and why do they do it?
Comment: What is the source for Americans to count in Hebrew?
Answer: Otzar Ta'amei Haminhagim (cf.) explains that it is a remnant of a time when the spoken language was Aramaic. Since the primary purpose of s'fira is the keeping track of days it is preferable to count in a language that enables the counter to keep track - i.e. a language the counter understands.
Comment: @SimchasTorah - Because the spoken language for (most of) us is not Aramaic.  I have a friend (who is neither a Yemenite nor is Aramaic his mother tongue) who counts Sefirah in English.
Comment: @SimchasTorah My rule has always been, if you have to read the night's count inside because you can't in your head smoothly figure out what to say in Hebrew, you should just be counting in English.
Comment: Which leaves the question why we do not
Answer: They preserve the Babylonian custom, where the native tongue of most people was Aramaic. The earliest attestation of saying the sefira in Aramaic of which I am aware is in the siddur of R. Saadia Gaon (see here, bottom of the page).
Comment: Rav Saadia Gaon's translation is in Judeo-Arabic, not Aramaic.
Comment: did you even look at the page? yes Resags commentary and translation is in Arabic but the formula for Sefirath ha`omer used in his siddur is in Aramaic
Answer: See Shulchan Aruch Orach Chayim 489, 1 in Magen Avraham sk 2 reported textually in Mishna Berura sk 3 :

ופשוט שמותר לספור בכל לשון ודוקא בלשון שמבין ואם אינו מבין לשון הקודש וספר בלשון הקודש לא יצא דהא לא ידע מאי קאמר ואין זה ספירה כן נראה לי.
And obviously, it is allowed to count in all language, only language which he understands; if he doesn't understand Holy Language (Hebrew) and has counted in Holy Language, he doesn't fulfill the Mitsva, because this is not a count.

The source of this discussion may be in Mishna and Gemara Massechet Sota, (Mishna 7, 1) we can understand from the Tosfot Yom Tov that the intended effect of some verbal mitsvot contains understanding. For counting it is easy to understand.
What if someone said and understand and someone ho doe's not understand wants to fulfill by hearing him?
The Berayita in Menachot 65b taught: "וספרתם לכם, שתהא ספירה לכל אחד ואחד" that each one need to make the count. So, the count of the few people who understand is not relevant for the "non-understanders". But the Bet Yosef reported from the Teshuvat Harashba that one may fulfill the mitsva through the count of the Shaliach Tsibur. Magen Avraham explains that by the rule of Shomea Keone (who heard is as if repeat what he heard). We can ask if this can help when the person who heard does not understand what is said, but who speak understant what he says. I am pretty sure that the answer is negative.
Aramic was the language the most used in Jewish's areas, the lingua franca this is also the reason for which the Targum is in Aramean.

Yemenite Sefira


Do mathematicians Switch Fields of Expertise?

Question: I'm curious if it is common or quite rare for mathematicians to change their area of expertise, whether it be after their PHD or mid-career, how radical this change might be, whether it's often for reasons of evolving tastes or rather conforming to the type of research done at their institution, and any other thoughts anyone has on how mathematicians stake out the fields they will be producing research in, thanks =].
Comment: The great mathematicians usually seem to be involved in many fields.  I can't say much about great mathematicians today, but I looked up Terry Tao a few days ago and his research interests are extremely varied it seems.
Comment: If I remember correctly, Grothendieck didn't get into algebraic geometry until fairly late (it wasn't his thesis). Another example: Quillen studied partial differential differential equations in graduate school and went on to become a leading homotopy theorist.
Comment: There are a couple of relevant MO posts [here](http://mathoverflow.net/questions/69937/changing-field-of-study-post-phd) and [here](http://mathoverflow.net/questions/12684/switching-research-fields), and I like Gower's concise answer in the second link (recommended in a comment in the first link). Adam's answer below is in the same vein.
Comment: To supplement Akhil's comment: many people are aware that Grothendieck did not begin in algebraic geometry, many people seem unaware of the fact that he made fundamental contributions to the field he began in--- the theory of topological linear spaces, and specifically Banach spaces (Albrecht Pietsch's *History of Banach spaces and linear operators* is a good reference, although for Banach space enthusiasts only).  There are people in this area who say things like "if I remember correctly, Grothendieck went on to do things besides Banach space theory," and aren't kidding.
Comment: Wow, excellent comments everyone, very informative, thanks
Answer: I think it's rare for people to make a radical shift all at once, largely because it takes a long time to master a field.  However, it is much more common to start in field $X$, get interested in an adjacent field $X'$, then in an adjacent field $X''$, etc.  Iterate this enough times, and you end up someplace quite different from where you started.
If you are interested in working in a field which is a little different from your usual one, the best way is to seek out a collaborator in that field.  Probably my most productive collaboration started because I got interested in a problem in a field in which I was not an expert and approached someone who was.
Answer: If you define "area of expertise" narrowly, then all mathematicians change areas of expertise.  It's extremely rare for people to focus on only one kind of problem.  If you look at the publications of anyone who has been publishing for decades, you will see considerable drift in what they work on.
If you define "area of expertise" broadly, I think you will find that most people do not change areas of expertise.  Rather than "expertise", it might be more accurate to talk about interest.  Most people's broad mathematical interests do not change that much.  If someone doesn't care about geometry at age 30, you will probably not find them doing geometry at 50.  If someone is steeped in geometry in their 20s, what they do in their 50s often has a geometrical "flavor" even if is not pure geometry.  The methods and tools that people use change a lot, sometimes drastically.  But the underlying interests tend not to.  There are exceptions, of course, but that's why people notice them--- they're exceptional.  Nobody is astonished to see an geometer, broadly defined, stay an geometer.
All of the abrupt shifters I personally know switched shortly after grad school.  These shifts often occur because one's focus in grad school is determined more by the environment (e.g. an advisor, the faculty at at a single school) than the individual.  It takes years to develop mathematical tastes.  In the meantime you sort of adopt, or try out, the tastes of the people you are learning from.  It's not unusual for a grad student to accumulate enough material for a dissertation in area X, while in realizing in the process that they are more interested in Y. So you see CVs where someone does a thesis and a handful of papers in X, and suddenly it's just Y after that.
You ask if researchers shift to "conform to the type of research done at their institution."  I would say a definite no to this.  At research universities you do have to conform (at least partially) to get hired in the first place.  If you look at mathjobs.org, for example, you will see that research universities usually specify (at least partially) a research area in job announcements.  So: if you don't conform a little, you don't get hired--- or, more likely, you don't apply in the first place.  If you are hired then you have interests in common with at least some faculty, and it's natural that you might work with them.  But generally speaking, once you're hired, nobody really cares what your research direction is, provided that you have one (and are otherwise playing an active role in the department).  If you only publish sole-authored papers, or only publish with people from universities besides the one that you work for, no reasonable person will hold that against you.  There is no pressure to conform in the sense that I think you are asking about.
A final thing, on your choice of words in "how mathematicians stake out the fields they will be producing research in."  Generally mathematicians do not choose a field first and then begin producing research (except perhaps at the very beginning, ie grad school).  Research problems come first, and over time, depending on what the perspectives and tools one acquires, one finds oneself situated in a given field.  For example, it's rare for someone who has not done X in the past to just wake up and say "OK, I'm going to do X now."  What's more common is they will be working on a problem that isn't explicitly about X, and in trying to solve it, they eventually realize (or learn form someone else) that some X might help.  So they go and study X a bit.  Sometimes this leads to a solution to the original problem, and case closed, and they don't think about X ever again.  And sometimes it's a dead end.  But sometimes it leads to them reading the literature on X, thinking about X more often, maybe eventually contributing to the literature on X.  This is the kind of gradual shift of interests Adam Smith talked about in his answer.  It doesn't generally arise out of a conscious desire to switch fields or to "stake out" a field.  It just happens.
Answer: From my experience, a radical area change is rare, but this does happen. In grad school I knew a numerical analyst who started as a number theorist. Another professor I knew in grad school had wandered from field to field throughout his career. He started in topological groups and ended up in mathematical physics. One my colleagues started in differential equations and then mid-career decided he would switch to difference equations (this isn't as big a move as my previous two examples).
Why do people switch? Sometimes a field "dries up". Results get hard to come by and it's time to move on to greener pastures. Sometimes people get bored with their field and just want to try something new. I think this sort of thing is, for the most part, rare because it takes time to build up the background necessary to get started in a new area.
Edit: An interesting example of a major mathematician who "switched" fields is L. E. J. Brouwer. See:
http://en.wikipedia.org/wiki/Luitzen_Egbertus_Jan_Brouwer
http://www-history.mcs.st-andrews.ac.uk/Biographies/Brouwer.html
Brouwer left topology and analysis (you may know "Brouwer's Fixed Point Theorem") because of a major philosophical shift. He didn't believe in that stuff anymore.
Answer: It is not that uncommon for interests to drift, but the commonly cited examples (e.g., Grothendieck, Quillen, Serre, Mazur, Gelfand, Witten) of impact on relatively distant fields are extremely atypical. The fact that famous mathematician M was able to do top work in subject X, and then again in a faraway subject Y (and later in Z, and ...) says more about famous mathematicians than what is possible under more common conditions.  Late-career changers of specialty such as Mumford, Smale, Freedman or Langlands demonstrate that there is more freedom with a Fields Medal or without teaching obligations.  Somebody of more ordinary abilities and circumstances may be more limited.
In computer science Len Adleman spent a year in a biology lab and learned the techniques that he used to found DNA computing, but his case is similar to that of the Fields winners.
Paul Cohen's work in set theory might be an example but he switched to a field that had not reached maturity, still had its most basic questions left open and was not a densely populated research area at the time.  Mumford and Langlands both ventured out of very technical, mature subjects into what was at the time relatively open mathematical territory.
Hales' work on computational approaches to the Kepler conjecture and proof formalization was a switch from his original interests in representation theory.
It's hard to cite lower-profile examples, because they are less visible and not heard of as often.  Changes are most common in the first few years after the doctorate.
Answer: For a period of time, Robert Langlands switched from number theory to studying mathematical physics in statistical mechanics.


Colorful term for someone with a long-overdue library book

Question: I'm trying to find a humorous term for someone who still has an overdue library book after a number of years. I first came up with "delinquent lendee", but I'm sure there's something more apropos or alliterative.
Comment: Personally I'd call them a "dead-tree deadbeat."
Comment: Why beat around the bush? Call them what they are; a petty thief.
Comment: @TomO'Connor: such, uh, long-term borrowings are rarely *intentional* in my experience, so *thief* doesn't seem to apply. Plus, overdue fines are a good source of library income if/when they are collected, so such people are really benefactors-in-waiting.
Comment: Taserian, you could improve your question by giving us some more criteria to choose the best answer. Do you want to imply mild or severe disapproval? Is humor the most important consideration, or is transparency (i.e. the ability to convey the intended meaning without extensive context)? Etc. etc. Right now, this question is in danger of being closed as "not constructive", because there is really no objective way to choose a best answer.
Comment: This cartoon seemed appropriate: http://www.smbc-comics.com/index.php?db=comics&id=396#comic
Comment: @Marthaª Theft is still theft whether intentional or not.
Answer: How about ... tome raider?
Or book keeper (not to be confused with bookkeeper)
Comment: I like tome raider a lot, I'll be using it.
Comment: "There is one thing you should learn/When there is no one else to turn to/Call...for English Chicken! (_cluck, cluck, cluck, cluck_)/Call...for English Chicken! (_cluck, awk!_)" (with apologies to [Super Chicken](http://en.wikipedia.org/wiki/Super_Chicken) )
Comment: I'd like to chime in that while I do also like *tome raider*, my upvote is mainly for *book keeper*, which I find deliciously wry.
Comment: Haha, thanks, @Gnawme... I know what my avatar is going to be now.
Answer: Here are a few I came up with, choose one that suits you:

Book-Bandit
Book-Clip
Book-Plunderer
Book-Pocket
Book-Lifter
Library-Climber
Library-Breaker
Book-Breaker
Biblio-Bandit
Lendup-Artist
Biblio-Bezzler
Biblio-Prowler
Book-Prowler
Comment: I like *Bilbo-Bandit*. (Biblio Baggins?)
Comment: @muntoo lol. also, Biblio-Hobbit. :D
Comment: Lol -- none of them accounts for a simpleton who just failed to show up. Too bad. :)
Answer: Assuming they have no intention of actually returning the books, you might call them biblioklepts.
Comment: Biblioklepts! I like the word, myself, but I'm not sure if my audience would get the idea directly.
Comment: @taserian You work at a library no? A library should encourage learning. If you've got it in you, encourage them to look it up. **Use this one**
Comment: I don't work at a library; this was used in a Toastmasters speech. . .
Answer:
tome hoarder
book miser
deadbeat borrower
literary liberator
slow reader
library annex (particularly if they have a number of books)
library benefactor (due to overdue charges)
Comment: I literally (dare I say it?) laughed out loud at *slow reader.*
Comment: Yes, *slow reader* is excellent!... if provided sufficient context.  The other (also very good) choices on this list are less dependent on knowing beforehand that we're talking about severely overdue library books.  Indeed, for many of them we can figure out the context from the term itself.
Answer:
reference renegade
dewey decimal delinquent
archive absconder
folio fugitive
overdue outlaw
circumforaneous card catalog crook
hard cover criminal
"his library card was his mugshot"
the unshushable
Comment: That's a lot of alliteration.
Comment: @Caleb - Alliteration is mentioned by the OP, but yes, it is.
Comment: I loved this, but "Dewey decimal delinquent" and "archive absconder" ruined my ability to breathe, since I was laughing so loud!
Answer: Perhaps scofflaw could be appropriated for this use.  It's probably what I would say in the same situation, off the top of my head.
Answer: I believe the accepted term is "delinquent borrower", but that's not very colorful.
Answer: Someone who has borrowed and kept a library book for such a long time that the book is now ancient history could be called a biblionecrophile.
If they haven't returned the book because they suffer from an obsession with hoarding books, then they're a bibliomaniac.
Comment: perhaps you meant `lignonecrophile` or `necrolignophile` for someone obsessed with dead treas?
Answer: How about using "The Loan Ranger"
Answer: (Just checked to make sure you're an American over 30)
How about Costanza or even "Can't Stands Ya".
Answer: AWOR: Absent WithOut Renewal.
Easy to remember.
[a la AWOL: Absent WithOut Leave].


What kind of wok should I get?

Question: I saw the question on the site about preparing a wok, but I'm curious what kind I should get. I have heard of stainless steel, carbon steel, aluminum, etc. Also, there's a non-stick variety. I'm new to stir fry and will be cooking on an electric ceramic stovetop.
Answer: You should get a carbon steel wok with two short handles (not one long handle).
You want the steel to build up a patina of oxidized oils, which rules out stainless steel and aluminum and non-stick. You could conceivably get a cast-iron wok, but those are really heavy.
You want the two small handles so you can pick up the wok, but you don't want long handles that will dump hot oil or food everywhere if you bump them. Unlike a saute pan, you don't toss the pan, you toss the food. (Tossing the pan pulls it away from the flame, which is bad when stir-frying!)
Your best bet is to go to an Asian grocery. You'll be assured of getting a product at a good price. Shouldn't cost more than $25, I don't think.
Oh, one other question is what sort of stove you have. If you have an electric stove, (a) I'm sorry, and (b) you have to get a flat-bottomed wok. If you have a gas stove, you can either get a flat-bottomed wok or a round-bottomed wok, but the latter only if you get a wok ring that holds the pan just above the flame. You want as much heat going into that pan as you possibly can manage!
Comment: As one of the electric stove people, I'd recommend the flat-bottomed wok over the ring -- you get better contact, and better heat transfer.  I'd prefer using a saute pan to a round wok and just not over-crowd the pan (which may require cooking in batches)
Comment: addendum -- if you have a serious commercial wok burner, which you don't, but if you did, then you'd want the long handle so you can toss the pan and get tasty burned oil flavors. But you don't, which is why your home-cooked Chinese food won't be as good as that at a good restaurant.
Comment: another addendum -- if you don't have a gas burner, or maybe even if you do, get a standalone induction burner (under $100), and use that for wok cooking. The heat is only in the _bottom_ of the pan, which is what you want. Gas tends to go up the sides, which is inefficient, burns your hands, and isn't ideal for stir-frying.
Answer: The Cook's Illustrated/America's Test Kitchen testers argue forcefully that a wok on an electric stovetop is suboptimal -- they're designed to sit on top of a fire or gas burner with flames licking around the base, and a wok's small area of contact with the heat source when used on a conventional hob results in something more like stir-steaming than stir-frying. They recommend a 12" frying pan/skillet instead. Other people's experiences may vary, but I haven't bothered with a wok since university and I would definitely question the need for one to make great stir-fry.
Answer: The best and cheapest solution I've ever see is the one I have.  It requires a deck, patio, or something though.
I went to Chinatown in Toronto and at a restaurant supply store bought a carbon steel wok.  It was about $25.  You can get them anywhere.  The secret to wok cooking is temperature.  In the US, burners are generally limited to 15k btu.  You need much more for the authentic taste.
What you need is a wok burner.  I bought one for one $100 at the same store.  It's basically a 7 inch wide triple fire ring burner made of cast iron.  It's enclosed in a 15x15 inch frame which the wok will properly rest on.  It's very strong and pretty large so I also use my 20 quart pressure canner on it.
This burner hooks up to propane, but you can get ones that use natural gas.  It's 66k btu.  Absolutely the best and cheapest purchase I've made in years.  It uses much less gas than grilling, is much faster, and I use it for a larger variety of food.
Note: these types of burners are not rated for indoor use.  They are incredible though.
Comment: I would go with cast iron. With a thicker bottom  Those are getting hard to find even in Asia. So carbon steel. As you need a hot bottom in them to cook. The wok burner is a + . But not a must.  You also want a lid for the wok, A 1/2 round rack & a round rack to set inside it.  All set. Most cooking in them is stir fry. But they are good for frying food & steaming with the racks in them. Flat bottom is best for stoves. The thick bottom is best for even heat across the bottom as you stir fry. But as said hard to find.
Comment: What brand was the wok burner? I'm struggling to find anything with that level of BTUs less than $1000
Answer: http://www.seriouseats.com/2010/06/equipment-how-to-buy-a-wok-which-wok-is-the-best.html
Read this. Great advice.
Woks CAN work great on an electric range. But you have to buy carbon steel, not non-stick.
Don't listen to the nay sayers. It works great. Try it!!
Comment: Non-stick is basically a euphemism for "short life span".
Answer: Supposing that you have a gas stove, a simple and cheap thin steel wok will stand you in great stead. They are tough, light and easy to shake about, and will take a wonderful seasoning with use.
(Seasoning refers to the layer of cooked in oil which gives the wok its "non-stickness". it is very important to avoid washing up liquid, just cleaning it with hot water and a brush or similar).
I personally like a long handle; but a wok ring is essential as Harlan says.
Comment: And to translate for the Americans : "washing up liquid" == "dish soap"
Comment: Seriously? "Dish soap"? Wow, learn a new thing every day...
Answer: I've experimented with a few. As mentioned here non-stick woks get quickly ruined with the high heat you need and given that you pay extra it probably isn't worth it.
Probably my main advice would be to get a wok of the right size, for cooking at home I suggest tending towards smaller rather larger. Obviously a smaller wok is easier to heat up.
Personally, I would go for a cheap and cheerful steel wok which requires a bit of seasoning. Don't use heavy astringent chemicals or abrasives when cleaning it.
Answer: For an electric stove, I wouldn't even bother.  Buy a good quality dutch oven and use that instead.
For a gas stove, carbon steel or just plain-old-steel is vastly preferable to aluminum, stainless, and especially to nonstick.  According to Mrs. Chiang's cookbook, aluminum and stainless won't hold the heat right.  According to me non-stick is a bad idea; the high heat will destroy the coating, and you will end up with non-stick stuff in your food.
Go to your local chinese grocery, and get it there.  Prices will be cheaper and quality higher.
Comment: Why not use a wok for an electric stove?
Answer: I would suggest a flat bottomed carbon steel wok, only due to your heat source of the ceramic/flat top range.  Any other type of wok would probably not give you good results.  Anything with a non-stick surface is going to be a limiting factor when it comes to high heat.  And stir frying needs quite a bit of heat.  A round bottom would also not be effective as it would not have the surface area to transfer heat.
If you were able to upgrade to a portable gas cooker, this would greatly improve your stir frying experience.  I would still recommend a flat bottom wok, as western style gas ranges are made for flat bottom pans, and do not concentrate it in the center for a wok.  Thin carbon steel, as to transfer the heat to the food easier.  As for handles, I would suggest one handle, just to keep the flame/heat away from your hands.  If you had a wok ring to keep things stable, then a round bottom would be better.  The round bottom is easier to flip/move food.
Answer: I got an aluminum filled stainless steel wok. One short handle, one long. Gas range.
Works quite well, even, fast heat distribution.
No worries about having to season the thing or dry thoroughly to prevent rust.
Wok temperatures frequently get too high for teflon to last more than a year. You might as well pour money down the drain on one of those.
My Wok is 8 years old, and happy, shiny as the day I bought it.
I use it a lot.
Slightly flat bottom, so it doesn't go rolling everywhere.
Answer: Since you are new to stir fry I would suggest you to buy the non stick one. So you don't have to worry about seasoning the wok and all that. Then if you find yourself in the future in the need of a different wok you can buy it then.
For now I'll go with the easiest one
Comment: This is not good advice. The whole point of stir-frying is that the bottom of the pan be *extremely* hot and the food gets progressively stirred onto and off of the bottom of the pan, developing browning and flavor but not burning because of the constant stirring. You cannot do that with a nonstick pan. You'll ruin the teflon and fill your food with carcinogens. If someone doesn't want to deal with high-heat cooking, they should stick to whatever flat pans they happen to already have. My suggestion is the real wok, plus a copy of From the Earth, a great Chinese vegetarian cookbook.

What kind of wok should I get?


How is NIST's Key Wrap (using AES GCM) different than normal AES GCM Authenticated encryption?

Question: From what I could gather, it seems like that NIST's key wrap (publication) provides similar security like AES-GCM Authenticated encryption. If this is true, why did we need a separate specification for key wrap in the first place ?
Answer: You can find some info in section B.2. "Comparison of Functionality with Other Authentication Methods" in NIST SP 800-38F, where it said:

Many authenticated encryption algorithms ... provide an efficient means of authenticating associated data that is not confidential ...

Digital signatures on ciphertexts or MACs on ciphertext can be verified without decrypting the ciphertext. ...

So obviously, NIST KWs don't allow authentication without decryption or associated header data.
But apart from NIST, you may also be interested in the paper Deterministic Authenticated-Encryption, where it gave a treatment on what does it mean to be a "key-wrapping" mode. To summarize, we can look at the following quote from the introduction section:

We call the goal deterministic authenticated-encryption (DAE) ... In a DAE scheme, encryption deterministically turns a key, a header, and a message into a ciphertext.

Where as traditional AEAD as treated semi-conanically in RFC5116: An Interface and Algorithms for Authenticated Encryption, a nonce/IV needed to be provided so as to provide so called "semantic security".
As to

Q: why did we need a separate specification for key wrap in the first place?

Determinism decreases the likelihood that misuse of the schemes happens, as could with non-deterministic schemes running on top of broken RNGs or compromised state.
Comment: I guess you could create an argument around the fact that key wrapping doesn't require a RNG *or state* to be kept. If the IV is non-random, it must be created using some kind of counter or pseudo-random scheme. Just thinking along here :)
Comment: GCM doesn't require IV generated using RNG, but I don't know how to edit this fact into the answer body nicely, so here it's in the comment.
Comment: " **If multiple invocations are necessary on
the same data for a system, then one method for ensuring that the ciphertexts are different would
be to prepend the data with a fixed-length nonce before invoking the authenticated-encryption
function.**"

This means that even these schemes need some sort of nonce if they're invoked multiple times, making it essentially similar to vanilla AES GCM.

@DannyNiu
Answer: One advantage is the recommended maximum number of invocations using a single key.

No limit on the number of invocations with KWP-AE or KW-AE. Encryption is stateless. (NIST SP 800-38F, "5.4 Limits on the Number of Invocations")
$2^{32}$ maximum invocations with AES-GCM using random nonces to avoid nonce collisions with a $2^{-32}$ security margin. Encryption is almost stateless - must be sure that keys are rotated before passing  $2^{32}$ encryptions. (NIST SP 800-38D, "8.3 Constraints on the Number of Invocations")
$2^{48}$ maximum blocks ($2^{47}$ maximum 256-bit keys) encrypted with AES-GCM using unique nonces to avoid a birthday collisions of encrypted blocks with a $2^{-32}$ security margin. Encryption is not stateless - synchronized persistent state is required over the lifetime of the key when encrypting.

Huge disadvantages vs AES-GCM and other modes and algorithms are:

No security proofs
Extremely slow
Only 64 bits of authentication
No modern conveniences such as AAD

To get practically limitless bounds - at least $2^{64}$ invocations using a single key with random nonces - you can use XChaCha20-Poly1305 or AES-GCM-SIV.
To use NIST-compliant algorithms and modes you may need to use longer nonces and add an explicit key-derivation step and then use AES-GCM - see Amazon KMS's approach for example.


Can I create a new color group based on an image that is on my artboard in Adobe Illustrator?

Question: I have an image of a beautiful Betta Siemese fighting fish and I'd like to create a new color group based on the colors that appear in the image. I placed the image on my artboard in Illustrator and want to know if there is a way that Illustrator can identify the colors and create a color group accordingly. So far, I clicked on the image on the artboard, clicked the New Color Group icon, selected the option Create from Selected Artwork selection in the popup window and clicked OK. However, the folder that is created does not contain any of the swatches. It comes up as an empty color group. If anyone knows how to get this to work, please share. Thanks a million! ~ Staci Jc
Answer: Use the Live Trace feature on your placed image. Go to Window > Object > Image Trace, and pick some options which allow you to get a traced art object in color. Now, expand your tracing by pressing the "Expand" button which should have appeared on your top bar of the Illustrator application. Only after this, would your raster image be converted into Illustrator shapes, so now you can create a new color group and you will find it populated with the swatches rather than empty.
Answer: Place the image
In the swatches below there is icon like folder (new color group) click on it and a pop name it.
Now click on the eye droppper and select the color
As soon as you click on the color the color is shown.
Drag that color onto the folder you have made it.


Does anyone know what this piece of glassware is?

Question:
I recently found this piece of lab glass with a jacket and spout. It says eubilicmeter but I cannot find any information about it online and I do not know what it is supposed to do.  It is hollow in the middle, sort of bell shaped. What is its name and what is it for?
Answer: I believe this is an ebulliometer, from the Latin ebullientem (to boil).
It's a used to measure boiling points. Clearly, there are some spelling issues with the sharpie label here.
Comment: There might be fewer spelling errors that it first appears.  I'd say that the sharpie could be "eobiliometer" (allowing for handwriting, especially on a slick surface, and where it looks like some ink might have rubbed off), which only mistakes an "i" for a "ul".
Comment: It certainly was supposed to read  'ebulliometer', but the question is if it really is an ebulliometer? It does not look like one, maybe it's just a part of it. It is a vessel with double walls with vacuum in it (see that sealed tube at bottom right?). The central volume is thermally insulated - an ebulliometer must have a part that is heated, I don't see anything like that here.
Comment: Yes seems like that
Comment: Actually, this is a fun question to punt over to the Indoeuropean SE. :)


Plain vanilla risk parity with trends forecasting power

Question: I have built an asset allocation model (plain vanilla risk parity) but I would like to adapt the initial asset allocation with respect to potential futures changes in the trends of the assets under management. Let's say I'd like to add a little bit of "active", staying in a quant framework. For instance, I'd like to forecast a switch in the bullish trend of fixed income securities to a bearish one and get a hedged position (reduce duration for instance) in my allocation.
Could you please suggest the main references by either academics or professionals for quant forecasting models (macro, investors' sentiment, behavioural etc.)? Any advise would be much appreciated.
I would appreciate something similar also with respect to liquidity: is there any quant model to tune my liquidity investment using forecasting methods?
Answer: Thierry Roncalli adresses the issue of expected returns in risk parity in Introducing Expected Returns into Risk Parity Portfolios: A New Framework for Tactical and Strategic Asset Allocation. Maybe this preprint  contains some useful ideas for you,


ubuntu server no audio output

Question: I need to deploy linux ubuntu servers (no desktop) with the ability to play audio files from command line.
After installing the ubuntu 12.04 server edition I installed:
sudo apt-get install libasound2
sudo apt-get install alsa-utils
sudo apt-get install mplayer

and then added my user to the audio group
sudo usermod -a -G audio myusername

After these operations I opened amixer and did rise all outputs to 100% on.
The problem is that I still cannot have any audio output.
I know for sure that the audio card works since when I run lubuntu live 12.04 on the same pc I can hear the audio output.
Does anybody know what I'm missing to have the server edition play audio files?
EDIT:
Well I found out the problem was the "Simple mixer control 'PCM',0" was off and this was the reason why the audio was not working. The command
amixer -c 0 set 'PCM' 90% on

did solve my problem. Well at least I think in this post there are all the command needed to activate audio on an ubuntu server. To display the current audio levels just type
amixer

and finally, after 'PCM', it is important to check that 'Master' is 100% on:
amixer -c 0 set Master 100% on

Comment: Output from mplayer?
Comment: Thank you the problem was solved, I missed the [off] on PCM
Answer: I recently had a similar issue on my Ubuntu 12.04 system. Clearly sound was working on the system since I had no issues with games and mpg123, but I was unable to get any audio output from mplayer. I solved it in this simple way:
sudo apt-get install mplayer2

ubuntu server no audio output


Check whether contact(s) are available

Question: I'm trying to build a contact list based on a available contacts.  However, how do I find a contact's availability?  I've synced my contacts list to Outlook, however looking through the available columns there doesn't seem to be anything for whether available status?  What is the best approach, is it necessary to check each contacts calendar?
Answer: You can use the Exchange Web Service API to get contact availability information. Details and samples can be found here: http://msdn.microsoft.com/en-us/library/exchange/jj220501(v=exchg.80).aspx#AvailabilitySection

Check whether contact(s) are available


What are some recommended open source tools for web browser history analysis?

Question: I'm looking at a series web browser histories from various browsers (IE, Chrome, Firefox, etc) and need to do some analysis.  All of these browsers store data much differently, but I was wondering if there was an open-source tool suite out there that would help me to analyze all of them.  If this is just wishful thinking, are there any open-source tools commonly used or is this type of analysis usually done manually?
Answer: Web Historian - not open source, but free (as in beer)
"MANDIANT Web Historian helps users review the list of websites (URLs) that are stored in the history files of the most commonly used browsers, including: Internet Explorer, Firefox and Chrome."
Odessa - just for IE, but open source
Answer: Another (not open source, but free) solution will be to use Nir Sofer's tools (you can find them here) with a batch file (built by you..)
Nir offers Cookies/Protected storage/Cache/History query software for all of the big browsers, that can be used through the console (he provides the flags and tutorials on his site for each freeware).
Since all of Nir's output files are exactly the same,  you can write a simple batch file that will dump all of the outputs to the same file and then analyse them with a program of your own.
Answer: Would be happy to know of any particular open-source tool that helps with analyzing all browsers.
One resource I bumped into which seems reasonably up-to-date and covers IE, Firefox and Chrome is Digital Forensics with Open Source Tools: Using Open Source Platform Tools for Performing Computer Forensics on Target Systems: Windows, Mac, Linux, Unix, Etc (Cory Altheide, Harlan Carvey). The link is to the google books online version, which has some pages missing.


Find the values of a and b

Question: Please help, I am stuck on the following question:
$$(x-a)^2=x^2-12x+b$$
Find the values of $a$ and $b$
Can you show me the working out?
Comment: Open term in LHS, compare both sides
Answer: Hints:
$$\begin{align*}(1)&\;\;(x-a)^2=x^2-12x+b\iff x^2-2ax+a^2=x^2-12x+b\\{}\\(2)&\;\;\text{Two polynomials are identical iff the coefficients of corresponding powers of $\;x\;$ are identical}\end{align*}$$
Answer: The left-hand side equals $x^2-2ax+a^2$. Comparing linear coefficients, we get $-2a = -12$ or $a=6$. Comparing constant coefficients, we get $b=a^2=6^2=36$. Hence $a=6$ and $b=36$.
Answer: If you don't know the theorem used implicitly in some of the other answers (that polynomial functions are identical iff they have equal coefficients), you can proceed more simply as follows. Expanding the square and subtracting it from the RHS yields
$$ (2a-12) x + b-a^2\, =\, 0$$
Evaluating the above at $\,x = 0\,$ yields $\,b-a^2 = 0\,$ so $\, b = a^2,\,$ so the above becomes
$$ (2a-12)x\, =\, 0$$
Evaluating the above at $\,x = 1\,$ yields $\,2a-12=0\,$ so $\, 2a=12,\,$ so $\, a=6,\,$ so $\, b = a^2 = 36.$
Answer: Well, firstly you should expand the expression and get
$$x^2-2ax+a^2=x^2-12x+b$$ then cross out $x^2$
$$a^2-2ax=b-12x$$
Which means that
\begin{cases}
-2ax = -12x \Rightarrow a=6\\
a^2=b \Rightarrow b=a^2=6^2=36\\
\end{cases}
So $a=6$ and $b=36$

Find the values of a and b


What's your favorite forum that combines the passions of Sound Design AND Music Composition?

Question: I'm wondering which forum do you prefer that covers both sound design and music composition?
Answer: Personally, I wouldn't like to read that kind of forum. Don't get me wrong but I prefer to follow Pros that are skilled in specific area than listen to people who "have some knowledge about this and maybe heard about that". If I have some questions about sound design google always sends me here on SSD, so it's just perfect :)
Oh, I hope it doesn't sound rude.
Answer: In a media context?
Answer: I presume you mean in terms of community; perhaps looking for a site similar to Social Sound Design but with an emphasis on music?
Have you tried Tape Op message boards?
Answer: hit the books man, and use your common sense...nobody taught others how to do things...plus many of those people are suffering form "the prince" commplex...they are good but they hit the saturation point where their big heads get on their way...as an artist I believe in collaboration, hard work of group of people who are dedicated and believe in making things open-source...If you look at todays music and movie industry, you will see its just the same cliche thing over and over again...why cause, everyone in the business is so blinded with goal of making money and fame, they forget the first reason they got into this field...sad but capitalism is killing every single industry...hence the mainstream genres, which I will not even bring up...plus its up to you if you wanna waste your day laming on internet or reinforce your foundation, by revising what you know, as they say don't take advice from someone who doesn't have it...do more with less.


Design Patents- What exactly are these patents on?

Question: What exactly is the patent FOR on the following items?  I see no notice of color, finish, size, materials, assembly method, etc.
D652759 (Pendant-Slit Pupil),
D683254 (Pendant-Round Pupil),
D682730 (Pendant Oblong Pupil),
D653151 (Plug-Slit Pupil),
D670191 (Plug-Round Pupil),
D674719 (Plug-Oblong Pupil),
D662005 (French-Slit Pupil),
D671439 (French-Round Pupil),
D665693 (French-Oblong Pupil),
D674720 (Post-Oblong Pupil),
D672681 (Post-Slit Pupil)
Answer: Usually when we think of a patent we are thinking of a utility patent. They cover the function of something.
These are all design patents. Design patents only cover the ornamental aspects of a item of manufacture. Ornamental can mean shape, texture, finish, color, printed material, patterns, reflectivity, translucency, etc. In many cases, as in the ones of these I have looked at, only the shape and a decorative pattern are shown and claimed. There are some design patents that say "in one embodiment the back is shiny" or "the back and front are in contrasting colors".
What something is made of and how it is made are complete non-issues in design patents. Just what it looks like is at issue.


Refering to Allah (SWT) as "him"?

Question: I was watching a khutba on youtube and the Imam referred to Allah (SWT) as "him". If you need a context to go with this the sentence was, "Allah (SWT) doesn't need us, we need him." I sometimes feel awkward when talking about my mom and referring to her as "she" so I was wondering if it is rude/haram to refer to Allah (SWT) in a term we use to refer to one another? Or is it that I'm just thinking too deep into it since no one is really trying to commit shirk?
Answer:
[Surat al-Ikhlaas]
Say, "He is Allah , [who is] One,
  Allah , the Eternal Refuge.
  He neither begets nor is born,
  Nor is there to Him any equivalent."

Using common pronouns to refer to God
The first line of the above surah is one of many examples where God refers to Himself using the simple pronoun "هو" (He), the same pronoun used by Arabic speakers around the world to refer to each other.  Not only does He use it thus in His own holy scriptures, but in this case it is an explicit command — as per the imperative "قل" (Say) — to use the same term when referring to Him (at least in this context).
Similarly, the fourth line includes the pronominal suffix "ه" (Him), again the same suffix used by Arabic speakers everywhere.
So in the case of Arabic, at least, there is no reason to believe that referring to God by such common pronouns is in any way disrespectful, much less haram.
English is not Arabic
In Arabic, a gendered pronoun doesn't necessarily indicate that the noun it's replacing is somehow "male" or "female".  While nominally male, the pronouns "هو" and "ه" are also regularly used for inanimate objects with no discernible gender at all, such as "قمر" (Moon) or "كتاب" (Book).  As such, even though God is referred to as "هو", it doesn't necessarily mean that He is male like a human or an animal is male.  God is, of course, above all of His creation, and there are none like unto Him.
In English, however, the male pronoun does not work like that; "He" typically refers to a noun that has a clear physical gender, whereas "It" is used for those with no gender.  As Shaykh Hamza Karamali from the SunniPath Academy explains in a relevant article,

The presence of the neuter gender in English and its absence in Arabic
  (or French) causes linguistic mismatch. A consequence of this mismatch
  is that in English, if one uses the masculine or feminine pronoun to
  refer to something that is without natural gender, one is representing
  the thing  as a person, usually for powerful rhetorical effect. This
  rhetorical device is called personification, and is often used by
  poets.

This concept of "personification" is, I feel, the crux of OP's problem: By using the masculine pronoun "He" in English, it implies that God is somehow comparable to mere mankind, and that He is Himself somehow male.  However, using the gender-neutral "It" can be seen as demeaning; while "He" runs the risk of personification, "It" runs the opposite risk of depersonification, of treating the referenced noun as naught more than a mere object.
Gender-neutrality (or lack thereof) in English
As this problem of personification is a direct result of using a gendered pronoun, one way of getting around this issue in English would be to use the singular pronoun "They", which is gender-neutral.  This however introduces yet another potential avenue of misinterpretation: that of plurality (God forbid).  I feel this is, and will remain, a major factor in it not being adopted among English-speaking Muslims to refer to al-Wahid.
The universal "He" has historically been used for cases of gender-neutral or gender-inconclusive nouns, and much like the Arabic "هو" it didn't necessarily imply actual maleness.  However, recent movements forwarding gender equality have brought attention to the inherent masculinity of this pronoun, and left no true gender-neutral pronoun in its place — a problem that has been plaguing editors and writers (at least those overly concerned with political correctness) for a while now — and while there have been attempts to introduce new pronouns to the English language to fill this void they have yet to achieve significant mainstream support.
One common practice (adopted, I believe, from the Christians in their earlier English works) is to capitalize the pronoun "He" whenever it directly refers to God; despite having no Islamic basis, this particular construction is well-established among the English-speaking world as referring to a deity rather than a regular person.  While the word would still be pronounced exactly the same as the common "him" in spoken language, capitalizing it as one would a proper noun communicates a completely different meaning (similar to the difference between "god" and "God") which is not otherwise seen in English.
In conclusion
The use of "him" — especially when capitalized as "Him" — to refer to the Almighty has a history of use in English that doesn't necessarily imply personification or masculinity, and no other pronoun has stepped up to take its place yet.  Short of abandoning pronouns altogether and always referring to God by name (despite the fact that pronouns are clearly condoned in Arabic), the English language does not really provide any alternatives.
Never forget that God is al-Aleem, so regardless of the words you use or the limitations of the language you speak, God knows best whether you mean to glorify or to offend Him.
Answer: How to address Allah SWT is a major issue faced by Their (Unke) slaves. In the Qur'an Allah SWT addresses Themself in whatever manner pleases Them, but we cannot use that Authority to communicate with Them. We know very well how much praises Allah SWT expects from us slaves, then how can we take the liberty to use this type of disrespect of addressing Them as 'He' or 'Him'. In Urdu there are words like 'hum', 'aap' used often as respectful for or by respected individuals. When a slave of Allah SWT is so much conscious of respect, how is it acceptable to use disrespectfull
addressing Allah SWT? We do not know Allah SWT's Personality. But we can imagine what it could or has done. They has formed the whole Universe, have made the whole world inhabited, guarding the whole Universe without sleep, made so many marvelous creations now being discovered and utilzed by science. Can we not attribute the most highest respectful address? I regret that I cannot find words to express more respectful address of Allah SWT.
Answer: I'm pretty sure with a capital it's a Royal He. So maybe with lower case like "he"?
But I think searching up "Royal He" on google or any search platform(to an extent) will clear your doubts God SWT willing.
Have you heard of "Royal He"?
Have you guys not heard of it? I'm pretty sure its specific to God SWT so how is disrespectful the capitalized version?

Refering to Allah (SWT) as "him"?


What is the intuition behind TD($\lambda$)?

Question: I'd like to better understand temporal-difference learning. In particular, I'm wondering if it is prudent to think about TD($\lambda$) as a type of "truncated" Monte Carlo learning?
Answer: TD($\lambda$) can be thought of as a combination of TD and MC learning, so as to avoid to choose one method or the other and to take advantage of both approaches.
More precisely, TD($\lambda$) is temporal-difference learning with a $\lambda$-return, which is defined as an average of all $n$-step returns, for all $n$, where an $n$-step return is the target used to update the estimate of the value function that contains $n$ future rewards (plus an estimate of the value function of the state $n$ steps in the future). For example, TD(0) (e.g. Q-learning is usually presented as a TD(0) method) uses a $1$-step return, that is, it uses one future reward (plus an estimate of the value of the next state) to compute the target. The letter $\lambda$ actually refers to a parameter used in this context to weigh the combination of TD and MC methods. There are actually two different perspectives of TD($\lambda$), the forward view and the backward view (eligibility traces).
The blog post Reinforcement Learning: Eligibility Traces and TD(lambda) gives a quite intuitive overview of TD($\lambda$), and, for more details, read the related chapter of the book Reinforcement Learning: An Introduction.
Answer: I am a novice in Reinforcement Learning and I have been struggling for several monthes about the TD()'s logic. Initially it seemed to me that it was a successfull purely heuristic formula without any theoretical foundation. But nowadays,  I understand it simply as a mean's calculation, using the recurrent formula that states that when you a have a mean and a new value arrives, it modifies the mean by an amount equal to its difference with it (the mean) divided by the new values number.
To summarize, the exposed mean calculation is an instance of a general formula of recurrent mean calculation that uses as increasing factor for the difference between the new value and the actual mean multiplied by any number between 0 and 1. By the way, this number - usually called  step size parameter - can be dynamic, and in the first paragraph (usual mean calculation) its amount is the inverse of the number of values considered in the mean's calculation.
Intuitively, we can understand that it is an accurate estimation procedure independently the initial (guessed or not) value. With a high number of estimates (new values arriving), the initial values fades its importance, and that it can be extended to treat many (lambda) new values simultaneously.
Until now I have not found this explanation nowhere, even if it is very simple, and I am not so sure that it is sound. I will appreciate if someone let me know if this intuition is correct and if it has already been exposed somewhere.


What happens to marriage on the New Earth

Question: I think I can safely say that humans were designed not to operate as a single solitary person but as part of a unit of two -- both as referenced by Gen 3:16-17 (see mentions of husband and wife in said passages) and ingrained feelings that appear to be a part of every person I know of (near as I can tell anyway...). However, there also seems to be support for there being no marriage after we are resurrected in Matthew 22:30. Can someone clear up my confusion on this topic?
Answer: Putting the verse you just cited (Matthew 22:30) back into context will clear up a bit of your confusion. First of all, the question was posed by the Jewish leaders about tedious Jewish customs in an attempt to catch Jesus off guard, as they frequently tried to do. The chapter even goes as far as to specify that they were Sadducees, which did not even believe in the resurrection. Furthermore, Christ's answer that they will not be married nor given in marriage refers to this contrived example (if you look at the KJV translation, it says "they" rather than "people") and not to couples in general. So this verse does not provide much support against marriage after the resurrection.
My experience is that most Christians agree that marriage between husband and wife is ordained by God...at least for this mortal life. The Bible does not say much else about marriage after death, and there doesn't seem to be a consensus among the various denominations as to the state of marriage after death.
Answer: Another great question! Marriage is an earthly covenant set in place by God and is terminated when the flesh dies (death). You're right in your assumptions that there is no marriage after we die. On top of Matthew 22:30 (which personally I think is quite plain), there is 1 Cor. 7:39: "A wife is bound by law as long as her husband lives; but if her husband dies, she is at liberty to be married to whom she wishes.." and also in Eph. 5:31: "For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh.". The keyword here being flesh of course. Not only does the Bible speak of sex here, but it talks about a covenant that is bound by the flesh.
Marriage is an earthly symbol that represents a heavenly perfection. The marriage between God and man. We-as the bride of Christ-are betrothed to Him forever. That is the only marriage that will continue throughout eternity. What would be the purpose of marriage in eternity? If we read 1 Cor. 7 we realize that people are given in marriage because of the desires of the flesh (7:2, 7:9, 7:36). In eternity we will a spiritual body much like our current body, but totally different at the same time. Insead of a person that's ruled by our flesh we will be a people ruled by our spirits (by the Holy Spirit). 1 Cor. 15:44 says, "It (our bodies) is sown a natural body, it is raised a spiritual body. There is a natural body, and there is a spiritual body.".
In the book of Revelations John pains a beautiful picture of the Church as the Bride of Christ. That marriage is finally consummated symbolically when Jesus returns. There is even a marriage supper! In the age to come we won't be serving ourselves in everyday life, but Jesus. We will fully be given to Him. If we think that spending eternity serving Jesus is going to be boring then we probably have some theology wrong. The Creator of the universe in all His majesty comes and lives with us. He makes His home here. God with man- the ultimate act of humility and intimacy.
Answer: HI I don't know if the old marriage laws will hold true.  But I believe we will be able to make a better covenant with our spouses if we are truly soul mates and made for each other.  I don't beleive for one minute that the relationship we cultivated in marriage will simply disappear and not matter.  I can't imagine not being bonded to my spouse in eternity even in the event that one of us should die.  In my heart there is no better match for me out there and I believe that will continue throughout eternity.  So I believe we will continue to have relationships with our loved ones, whether they be family, friends or spouses.
Comment: Welcome to the site! I'd invite you to read the [FAQ] as well as http://meta.christianity.stackexchange.com/questions/692/what-makes-a-good-supported-answer
Answer: 1) In the resurrection it is our flesh that is raised up out of the grave. We don't get some other body to replace it so any covenant in our flesh (ie: with our spouse) will likely still remain (One Flesh).
2) In Mat 22:29 when Jesus said "You are ignorant of the law" he may have been referring to Deut 24:4 which would clearly states that the others "may not take her again to be his wife". So the last of the seven men would be her husband. The the others "may not take her again to be his wife".
3) In 1 Cor 6:16-20 it is mentioned that in the resurrection we are "raised up by his own power" then it says that we should not fornicate because "he that committeth fornication sinneth against his own body. What? Know yea not that your body is the temple of the Holy Ghost". My point is that once resurrected we are are still effected by our sexual union in our flesh, which brings me to point number 4.
4) Rev 14:4 The 144,000 male virgins that will be set apart unto Christ after the first resurrection are said to be "not defiled with women", which makes little sense if our bodies are remade with no union with which to be defiled by.
These are the few scriptures that I hope answer this question.
Comment: Where is your evidence for these points? Point 1 seems very contentious - what about those whose bodies get destroyed? What about those whose bodies get turned into fertiliser, into food, and then into other people's bodies?
Comment: @curiousdannii, Thank you for your question. In point 1 I am referring to the long standing religious tradition that Jesus in fact shows scars in his hands to Thomas in John 20:27. Also to 1 Corinthians 15:52 that states that those that are alive and remain are "changed" and the "dead raised". This would be a strong indicator that our bodies are changed not replaced. I hope that answers your question. If it does not please let me know.
Answer: Anyone who assumes we will not still be with our spouse after death, Doesn't understand. When God intended a perfect world, He made a Man, and His woman in Paradise with perfect commumion with him...The World was good there. God, Man , and Woman.
As for the verse that explains not marrying during the resurrection, I am sure He meant the title and reproduction.
Comment: Welcome, from a newcomer to another! What do you mean by "He meant the title"? And do you have any Scriptural or doctrinal basis for this claim?
Comment: Welcome to Christianity.SE. We are happy to have you participate and answer questions here. This question, however, falls below the par for what we prefer for answers. This particular question is a bit out of scope as well because it is old (when we were first starting out). Please see the [faq](http://christianity.stackexchange.com/faq) and read the meta posts linked there. Then read some of the newer, highly voted q's and a's to get a feel for what we expect out of answers. Hope to see you around.


(no longer seeking answers) How to filter hiss from amp to speakers?

Question: I picked up an inexpensive 2x120W amplifier to drive my 8-ohm desktop speakers, and it produces a bit of a hiss, particularly when the treble is mixed further up which is what it seems to need. Is there a product or technique to put something between the amp and speakers that will filter this out?
Answer: No chance whatsoever.  At the output of a power amp, "hiss" is nothing you can get rid of without getting rid of the signal in the high frequencies as well.
However, you may want to check that the amp is receiving a signal at the proper level it expects.  If the signal level is too low and you compensate by turning up the amp, you'll automatically turn up preexisting hiss as well as hiss from the preamp stages.  This is nothing you can fix at power stage levels.
Comment: Is there really no chance whatsoever? Not even with a linear supply and proper grounding? Please elaborate.
Answer: If the amp is the source of the hiss there is nothing you can do. Some computer headphone jacks have weird noises going through them when devices are connected. But if it's not that and the hiss is before the amp you can try this:
Make sure that the signal going into the amp is balanced and at line level or at least shielded.
Make sure your connections are proper and wire gauge is right, and that the computer and power amp have the same ground.
Answer: Is it a 50Hz humming, or just a hiss? If it is the former, see http://www.electronic-products-design.com/geek-area/electronics/audio/solving-audio-hum-problems.
Is your system grounded properly? Do you use shielded cable?
On my system, I reduce volume to a point where hissing/humming is inaudible, and increase volume at the audio source (TV, radio). I am certain some component in my amplifier (the switching mode power supply comes to mind) is misbehaving and emitting some highfrequency noise, but I don't have a good enough oscilloscope to find the source.
Another cause can be the amplifier chip itself receiving a lower voltage than it can handle. I have some off-the-shell TDA7297 amplifier boards which hiss horribly at 12V, but this goes away when they receive 18V.
The good news is that you can play an audio file through this amplifier, and make a recording of it with Audacity, then compare it against the original. With some effort, you can learn the frequency of the hissing.
My best guess is the switched mode power supply - you will need a real linear power supply.  Ask on the hamradio.SE. My second guess is too low a voltage to the amplifier chip.
Hope it helps.
Edit:
It seems the most prudent approach is to go through the amplifier with an oscilloscope that can show waveforms down to 5mV.
It's also recommended to have a central grounding point (to avoid ground loops I presume). Ground is just 0V, I would run shielded wire from all the boards in the amplifier directly to 0V at the DC voltage input.


Accessing the return value from an IronRuby Dsl

Question: I am trying to create a Dsl which will have instances that live in
individual Dsl .rb files and then run them from the CLR.
I want to create and set the values of the Clr object in IronRuby and
then somehow have access to the CLR object after the .rb Dsl instance
file has run.
Here is my Clr object which is very simple at the moment:
namespace Horn.Core.Dsl
{
    public class BuildMetaData : IBuildMetaData
    {
        public string Description { get; set; }
    }
}

I have the following module which I am using to specify my Dsl and which
will create an instance of the BuildMetaData specified above:
module MetaBuilder
  module Dsl
    module Main
      attr_accessor :metadata
      def install(name, &block)
        @metadata = Horn::Core::Dsl::BuildMetaData.new
        yield self if block_given?
      end

      def description(desc)
         @metadata.Description = desc
      end

      def get_metadata
          @metadata
      end

    end
  end
end

include MetaBuilder::Dsl::Main

I somehow want to be able to get the @metadata property from the Clr
code after an instance of the Dsl has ran.
An instance of the Dsl looks like this currently:
install :horn do
  description "A .NET build and dependency manager"
end

My C# code looks like this currently:
var engine = Ruby.CreateEngine();
engine.Runtime.LoadAssembly(typeof(BuildMetaData).Assembly);
engine.ExecuteFile(buildFile);
var klass = engine.Runtime.Globals.GetVariable("get_metadata");

Is there anyway I can get at the @metadata property without having to
pollute the Dsl instance?
Answer: For anyone who is interested, I managed to solve this by creating a
singleton to house an instance of the BuildMetaData class.
My Ruby code ended up looking like this:
module MetaBuilder
  module Dsl
    module Main

      def install(name, &block)
        yield self if block_given?
      end

      def get_from(name, url)
        puts name
        puts url
      end

      def description(desc)
         meta.metadata.Description = desc
      end

      class MetaDataAccessor
        attr_accessor :metadata

        private
        def initialize
          @metadata = Horn::Core::Dsl::BuildMetaData.new
        end

        public
        def self.instance
          @@instance ||= new
        end

        def self.get_metadata
            @metadata
        end
      end
    end
  end
end

def meta
  MetaBuilder::Dsl::Main::MetaDataAccessor.instance
end

class ClrAccessor
  def get_build_metadata
    meta.metadata
  end
end

include MetaBuilder::Dsl::Main

I created the MetaDataAccessor to keep a singleton BuildMetaData
instance.
I could not work out the C# code to access a fully qualified class that
is nested in between modules so I created the ClrAccessor class to
provide access from the Clr.
My C# code ended up looking like this:
var engine = Ruby.CreateEngine();
engine.Runtime.LoadAssembly(typeof(BuildMetaData).Assembly);
engine.ExecuteFile(buildFile);
var klass = engine.Runtime.Globals.GetVariable("ClrAccessor");
var instance = engine.Operations.CreateInstance(klass);
buildMetaData = (BuildMetaData)engine.Operations.InvokeMember(instance,
"get_build_metadata");

I am fairly sure there is an easier way but for me it is progress.
Any input into this "round the houses" approach would be appreciated.


Kunneth formula for motivic cohomology

Question: I was wondering when the Kunneth formula holds for motivic cohomology:
$$
  H^p(X,A(\alpha)) = \bigoplus_{i+j=p;\beta+\gamma = \alpha} H^j(X,A(\beta)) \otimes H^i(X,A(\gamma))
$$
where $H^p(X,A(\alpha))$ is defined as you wish: by higher Chow groups, Hom groups in $DM(X)$, etc... The case I'm most interested in is $A= \mathbb{Q}$ and $M(X) \in DM(\mathbb{Q})_{\mathbb{Q}}$ in the thick sub-triangagulated category generated by the $\mathbb{Q}(n)$, $n\in \mathbb{Z}$.
Answer: I now remember a nice argument, why there's no Kunneth formula for Chow groups of $X \times X$ unless $X$ has a Tate motive. Let $X$ be smooth projective of dimension $d$.
We start with a decomposition of a diagonal:
$$
[\Delta] = \sum_{i,j} \alpha^i_j \beta^{d-i}_j \in \oplus_i CH^i(X) \otimes CH^{d-i}(X)
$$
We can assume $\alpha^i_j$ are linearly independent.
In this case we can show that $\alpha^i_j$ form a basis of Chow groups and
$\beta^{d-i}_j$ is the dual basis.
Indeed, as a correspondence $[\Delta]$ acts as identity on Chow groups,
so for any class c, $$c = [\Delta]c = \sum_{i,j} \alpha^i_j deg(\beta^{d-i}_j \cup c),$$
and the claim follows if we substitute $c = \alpha^i_j$.
Now $CH_i(X) = Hom(\mathbb Z(i)[2i], M(X))$ and we can consider the set of $\alpha^i_j$ as a morphism of motives $$\oplus_{i,j}\mathbb Z(i)[2i] \to M(X).$$
A simple computation shows that it is an isomorphism with the inverse given by $\beta^i_j$.
And of course, on the other hand, if $X$ has a Tate motive, then Kunneth formula for Chow groups follows (it doesn't answer the question, since I only consider smooth projective varieties).
Answer: I don't think so; for example if X is Spec(Q) then this doesn't seem to be true.  If you define, for any $Y$ in this thick subcategory, $\mathbb{H}(Y)$ to be the bigraded ring $\oplus H^s(Y, \mathbb{Q}(t))$, then I'd expect there to be a spectral sequence of the form
$$
{\rm Tor}^{{\mathbb H}({\rm Spec} \mathbb{Q}))}(\mathbb{H}(X),\mathbb{H}(X)) \Rightarrow \mathbb{H}(X \times X)
$$
instead, i.e. you should take the module structure over the motivic cohomology of a point into account on the righthand side of the formula you were proposing.
Answer: Correct me if I'm wrong. I think here is how it goes.
For any $X$ and any Tate motive $M$, there is an isomorphism of modules over $H^{\*,\*}(Spec F)$:
$$H^{\*,\*}(M(X) \otimes M) = H^{\*,\*}(X) \otimes_{H^{\*,\*}(Spec F)} H^{\*,\*}(M).$$
Remarks.

Right hand side makes sense, since $H^{\*,\*}(M)$ is indeed a module over $H^{\*,\*}(Spec F)$
When $M = M(\mathbf P^n)$, this is the the statement of the projective bundle theorem.
It's unclear to me how to write down the individual terms $H^{p,q}(M(X) \otimes M)$ it terms of cohomology $M(X)$ and $M$.

To prove the theorem in this form it is sufficient to consider the case $M = \mathbf Q(n)$.
Note that $H^{\*,\*}(\mathbf Q(n))$ is $H^{\*,\*}(Spec F)$ with bidegree shifted by (0,n), therefore tensoring with this module is the same as shifting the bidegree by (0,n).
And the same thing is in the left-hand side, according to Voevodsky's Cancellation Theorem.
Answer: There is a paper by Dugger & Isaksen called Motivic Cell Structures in which they establish a Künneth formula for various cohomology theories that are represented in the $\mathbb{A}^1$-homotopy category, provided the object $X$ satisfies some sort of cellularity condition which is similar to the requirement of having a Tate motive.
Of course, as Tyler suggested this Künneth formula is of the form of a spectral sequence over the motivic cohomology of the ground field, to wit $\mathrm{Tor}_{H(\mathrm{spec}\; k)} (H(X) , H(Y)) \Rightarrow H(X \times Y)$.
In general, this spectral sequence fails, as can probably be seen by all the counterexamples already given, and certainly can be seen by considering $\mathrm{spec}\; \mathbb{C} \times_\mathbb{R} \mathrm{spec} \; \mathbb{C}$ with $\mathbb{Z}/2$-coefficients, where the motivic cohomology rings are known in their entirities (These calculations also appear in papers of Dugger & Isaksen on the motivic Adams spectral sequence).
Answer: Very briefly, I believe the following is true: Motivic cohomology does not satisfy a Kunneth formula on the level of cohomology groups, but it does satisfy a kind of Kunneth formula on the level of some suitable derived category of sheaves. This should hold true in general for any Bloch-Ogus cohomology theory, I think.
Answer: Did you mean $H^p(X \times X, A(\alpha) = \dots$?
I 'm pretty sure Kunneth formula doesn't hold for motivic cohomology in general.
I think you'll get the wrong statement even when you specialize to the case of Picard group of a product of two curves of genus > 0.
However, for Tate motives over $\mathbf Q$ it probaby does hold. Seems like it's sufficient to check the case of $\mathbf{P^n}$ for which motivic cohomology "coincide" with the usual cohomology.
Comment: This is exactly what I had in mind. In the case of a mixed Tate motives, it feels like this is equivalent to Ext^2(A(0),A(n)) = 0 for the base field but I don't know how to turn this intuition into a proof. Any thoughts?
Comment: I had a wrong impression, that $H^{p,q}(Spec(F), \mathbf Q)$ is nonzero only for $p=q=0$.
However, since it is not the case I agree with Tyler Lawson, that the formula must have tensor product over $H^{*,*}(Spec F)$ or something like that.
Otherwise even H^{*,*}(X \times Spec(F)) doesn't satisfy the decomposition.

Kunneth formula for motivic cohomology


Should I delete my own question if it turns out trivial after a comment?

Question: I had not given this question enough thought before asking it.  I went straight to looking for a reference without thinking about it.  Somebody pointed out the obvious solution in a comment.  Should I delete the question or give the commenter the chance to turn this into an answer (and earn reputation) ?
Comment: My own opinion is that it's fine to delete if you wish, before someone posts an answer. After someone posts an answer, it gets a lot stickier. I think you conveyed your appreciation well to the respondent; I think that's enough in this circumstance.
Comment: This is technically OT here but: in my mind it is more important you do something about the  [math.se] version: self-answer or delete, but please do not let the question just sit there unanswered.
Comment: Yes that was always the plan. I'm just busy with a toddler arm.
Comment: If you think that someone else might benefit from the answer, it does no harm to leave the question on the site. You can ask the commenter to turn the comment into an answer or, if necessary, provide a CW answer yourself. If you think the question is unlikely to be worth anything to others, you can delete it as Todd suggests.
Comment: I deleted the question on mathoverflow. It still lives in math.se where it is probably appropriate.
Comment: Toddler asleep, question updated: http://math.stackexchange.com/questions/1386382/sign-patterns-in-kernel-and-rowspace-of-a-matrix/1416164#1416164 Thanks for all your input.  Out of curiosity: Why don't you answer the question and we are having this discussion in the comments?
Comment: @Todd I prefer(at  least from now on) to not delete my question which  turns out trivial after a  comment. Because this would respect the  commenters help. But  I have  a  general question on the  philosophy and reason of  deletion:
Comment: What would be happen if  all question would  remain forever?So no longer we see "vote to  close" by 5 participant?
Answer: To answer the comment question, "Why not just answer the question instead of discussing in comments?", my belief is that your question is both too general and too specific for meta.  The specific question for meta was your question above, and (except for one snag), the specific meta question has served its purpose and could be deleted too.  The general question, how to decide, is a good question to which there is no good answer.  The community may decide a question should be closed if it does not meet certain criteria, but aside from not being spam or unfriendly, there are no rigid technical criteria.
In short, there is no good answer to the question.  It really depends on many factors, not just the content of the question.
Gerhard "This Answer Is A Snag" Paseman, 2015.08.31
Comment: - Lol such meta