Searching in comments for a specific OP of a question and a word used in comments

Question: I would like to search for my username user122424 and a specific word used in comments that I remember  from reading that comment to get back to it. How can I do that?
Comment: To be clear it was a comment directed at you / about you. Not one you wrote?
Comment: IIRC comments are not indexed by Google thus that's expected. SEDE means Stack Exchange Data Explorer. See the answer. // The feaure is unlikely to be added as comments are not considered as relevant.
Comment: @quid Yes, a comment to my question and not written by me.
Comment: I think you have to use SEDE or a datadump, likely somebody else will provide details. There is no way on-site.
Comment: @MartinSleziak it seems I misunderstood something in the past.
Comment: @quid That's not good. What's SEDE ? Could possibly this feature be added to stackexchange site ?
Comment: @quid I have tried google but it hasn't found what I have remembered to be under my question in the comment.
Comment: @quid I somehow doubt that Google distinguishes between posts and comments in some major way - I guess the Google crawler simply checks what it sees on the page. (I agree that it would not surprise me if some comments might be missed by the crawler, especially in case when there is many comments. And certainly Google is rather suboptimal tool for searching comments.) Just to test is here are some Google searches which clearly find posts based on the comments [dictatorship anarchy](https://www.google.com/search?q=dictatorship+anarchy+site:math.meta.stackexchange.com) or ...
Comment: ... [proviso rubbish](https://www.google.com/search?q=proviso+rubbish+site:math.meta.stackexchange.com), in both cases searching on meta. (I hoped I would be able to find some notable comment or clever pun as an example. But since I wasn't able to recall something like that, I just tried with some random comments - but I chose such comments which contain some distinctive word.)
Answer: Stack Exchange API have a function to return replies to specific user, so it is possible that you could somehow search among replies to you using this. But as I am not really familiar with using the API, I won't be able to suggest details of such method.
As mentioned in the comments, you could use the SEDE (Data Explorer). This was suggested also in older similar posts on this meta such as: Searching comments or How to browse or search comments?. You can also check some posts on Meta Stack Exchange, such as: How can I search for specific comments? pr Can I search my comments using some keyword(s)? (There are also a few feature requests about this: Ability to search comments would be useful or Add Ability To Search Comments Only. So if you think this would be a useful improvement, you can upvote those.)
Most likely interpretation of your question is that your looking for the words which contain both your username and also a phrase you're searching for. I will also include some other queries. Don't forget to switch to the site where you want to search (all linked queries are for the main site here on Mathematics). You can change the parameters to look for different phrases. (Parameters can be changed directly in the url or in the boxes below the query.)

You can search for comments containing two different strings, such as 122424 and how. Notice that the query is case sensitive. Here is case insensitive version.
You can also search for comments by a specific user containing the given string. Again, here is also a case insensitive version. (One of the parameters here is the userid of the user whose comments you want to see. Just in case, I'll include links to Help with what is my user id and how do I check it? and What is my user ID?)
And one more query for comments containing the given word which were made under a post posted by a given user. (So in this case the userid is for the user who made the post, not the one of the commenter.) And here is a similar query, restricted just to the questions.
Query searching for combination of the given two words only under posts by a specific user.

Maybe it is worth pointing out that the queries search for a given string which might be a part of a longer word. But you can include also a space as a part of the string you're searching for - so this might help in situation when matches for substring/superstring would cause a problem.
And I will include the usual caveat that the data in SEDE are only updated once a week.
Of course, you can create many other queries - limited basically just by the available data and possibilities of SQL. You can find several examples of such queries in the linked posts.
Comment: [This](https://data.stackexchange.com/math/query/1259738/comments-containing-the-given-two-keywords?word1=122424&word2=how) would be OK for me, but it searches apparently only comments **to me** rather then comments from me and a possible word contained in some other comment. I guess so because all results begin with "@user122424: ".
Comment: @user122424 The query you linked searches for *two specific strings* in comments by *any user.* Since one of the strings is 122424, it is only natural that typically those will be comments mentioning your username. If you use the same query with the parameters [atom and poset](https://data.stackexchange.com/math/query/1259738/comments-containing-the-given-two-keywords?word1=atom&word2=poset), you can see that also one of your comments is among the results.
Comment: Since [you have mentioned](https://math.meta.stackexchange.com/questions/32091/searching-in-comments-for-a-specific-op-of-a-question-and-a-word-used-in-comment#comment142621_32091) that is was comment under your question, perhaps the third query could be useful for you. (The one which searches only among the comments under your posts.)
Comment: You link doesn't work. I remember this was under my question: "[Since user122424 has 3000+ reputations this is not] {possible}" The words in [] may not be precisely as in that comment but the word in {} is exact as in the comment, I believe. The comment I'm searching for is from 6th or 7th month from the year 2020.
Comment: @user122424 I don't really know where is the problem. To the best of my knowledge, this query [should return all comments under your posts containing the string possible](https://data.stackexchange.com/math/query/1261691/comments-on-my-posts-containing-the-given-phrase-case-insensitive?userid=122424&word=possible). Maybe the comment was deleted in the meantime? If the questions is not older than 60 days, you could check whether the question wasn't deleted under "deleted recent questions": [Is there any way to see my deleted questions or answers?](https://math.meta.stackexchange.com/q/13948).
Comment: @user122424 If you say that the comment was posted in the last two month, you could simply check the most recent comments on your posts - there probably aren't that many in that period. You can look at the [in the responses tab of your profile page](https://math.stackexchange.com/users/current?tab=responses&sort=comments) or you could [use SEDE](https://data.stackexchange.com/math/query/1262077/most-recent-comments-on-my-posts?userid=122424).
Comment: Can I reach also comments of my deleted questions ?
Comment: @user122424 Not through searching. But you can access you deleted questions (or answers) if you still have link to them somewhere. (As you probably know - after all, you've been on the site for quite a long time.) Still, there is some limited search for deleted posts that are at most 60 days old (and full search in your deleted posts at 10k+) - if you followed the link from my previous comment, you saw the details there.
Comment: To include at least one example, you should be able to see this deleted question - since it is your question: [Particular non-accessible category](https://math.stackexchange.com/q/3695691). It was posted on May 28 which is less than 60 days - so you should be able to find this question yourself using the "deleted recent question". (And once you reach 10k, then the no longer matters if you want to find your deleted posts.)
Comment: Yes, I can access that question, but can I access also **comments** to it ?
Comment: @user122424 It seems to me that we have digressed from the original question (which was about searching comments) quite a lot. Moreover, when reading some of your comments, it's a bit unclear to me what you're actually asking. Let me suggest that we continue [in this chatroom](https://chat.stackexchange.com/transcript/19138/2020/7/12) (if needed) - chat is more suitable for longer exchanges.


Keeping a leather saddle in good condition

Question: Is shoe polish a good or at least adequate solution for keeping a leather saddle in good condition? And/or better options?
Comment: Possible duplicates: http://bicycles.stackexchange.com/q/3897/1259 or http://bicycles.stackexchange.com/q/1751/1259 or http://bicycles.stackexchange.com/q/2392/1259 ? Do any of these answer your question?
Comment: @zenbike - Not really, but perhaps somewhat indirectly. I don't have a Brooks, but a 12 year old, well used, Selle Italia leather saddle and a quick search about using shoe polish to condition the leather did not get me to those questions. My question got me to an answer that serves my purposes.
Comment: Seems to me saddle soap would be what you'd use.
Answer: I guess shoe polish (the creamy one, not fancier new ones with sylicone and lots of synthetic polymers) at least won't do any harm, but maybe there are better choices.
Manufacturers advise the use of specific products (Brooks Proofide, for example) both for treating the surface against wear and tear induced by friction and the elements, but also for treating the deep layers of the saddle thickness, improving its mechanical characteristics, specially when new and yet uncomfortable, but also after some use and possibly abuse (mainly due to weather).
Leather tanning actually takes the subcutanous connective layer of cattle skin, which is rich in collagen, and treats it so that it can last longer. As such (at least it seems so to me) they have a "natural" affinity for natural substances, specially the lipo-soluble molecules found, for example, in Proofide itself: tallow, beeswax, cod oil, etc.
I like to look at my Brooks as if it was a somewhat living friend: we have a friendship, I treat it nicely and it responds by treating me nice. Even caressing it and silently talking to it is fine (at least is makes ME feel fine).
So with the Proofide I like to think I am giving something it likes: those fatty, variated, long-chain, apolar, gracefully degrading organic molecules, and not the inorganic, synthetic, industrialized, unlively plastified synthetic products one might choose as an alternative.
(and by the way, the thinnest layer once in a while is more than enough: that tiny can of Proofide will last for many years!)
Comment: I've heard people say they have used kiwi neutral shoe polish on their brooks saddles to no detriment.  Will it saturate as deeply as proofide? Probably not.  Using it will help keep it more protected than no product at all.  I'd recommend using it in a pinch if you're out of proofide while on the road, but a tin of proofide is relatively cheap.  Other leather care products which soften the leather may help in the break in period of your saddle, but probably should not be used for long term maintinance.

See sheldon brown's page on leather saddles
http://sheldonbrown.com/leather.html
Comment: That said, don't use a shoe polish containing dye. If you choose to use shoe polish, use the undyed neutral variety.
Comment: Proofride seems like a good option. Looked it up and the ingredients are: Tallow, Cod oil, Vegetable oil, Paraffin wax, Bees wax, and Citronella oil. Compared to shoe polish which has stuff like naphtha, turpentine and dyes in addition to some sort of wax. Proofride's pretty cheap too. FWIW - I don't have a Brooks, but a 12 year old, high mileage Selle Italia saddle that has developed some very fine minor cracking...
Comment: I also like the idea that Proofride covers most of the food groups. You could probably eat the stuff in a dire survival situation. ;~)
Comment: @wdypdx22 that darned paraffin spoils the meal!
Answer: Shoe Polish is ok but it is going to smell and plus the seat will not soak it properly and leave traces on your pants.
I use a glove oil... You can find one in any sports shop ... just look for oil which is used to soften the Baseball gloves. I have used it on my Brooks leather saddle and have had no issues in last 2 years.
Answer: I wouldn't recommend shoe polish with any dye in it at all, because it's only going to get on your gear, and even "neutral" shoe polish is probably less likely to be formulated for a high friction application like a saddle as opposed to a shoe where waterproofing and "gloss" are the more likely goals.
I agree with the previous answer that a natural product is likely to have a better result than the synthetic ones, especially a combination of conditioning oil and wax, like the Proofide that Brooks recommends.
Answer: Do not use glove oil on a Brooks saddle.  A saddle is a hammock in design, a glove is not, oil will break down the leather and make it eventually unable to handle the weight of a rider, and the leather will start to pull away from the rivets and you will have to adjust the tensioner a lot more frequently which will shorten the life of the saddle.
Brooks has been making their saddles for over 100 years, they know how best to treat their saddles.  So follow only their care instructions and not some bicycle guru on the internet, or your local bike shop, or some friend, etc.  Brooks even states in their warranty that the use of any other product other then Proofide on their saddle will void their warranty, end of story.


How large is the First Order in relation to the Empire?

Question: The answer to this question states that all of the remaining Empire supporters eventually became the First Order, but does not describe how large it is. I'm mostly curious in terms of total members and systems controlled.
Comment: Unknown: The First Order is based in the Unknown Regions, so the numbers you seek is unknown.
Answer: At this point, we can only speculate.
However, there is an indication that the First Order is slightly smaller when compared to both the New Republic and the (now disbanded) Galactic Empire. Both quotations are taken from Wookieepedia.

Many within the military believed that despite being outnumbered by the New Republic Starfleet, their technological superiority was so complete that even their smaller navy stood virtually unchallenged

As a result of the incidents leading up to The Force Awakens, it seems that the First Order is numerically smaller in scale than its predecessor.

With the First Order lacking the numerical superiority of the Galactic Empire, better equipped and trained soldiers resulted in higher trooper proficiency than the previous Galactic Empire.

Again, although not specific, we can gather from this that the overall size of the First Order was smaller relative to both the New Republic and the Galactic Empire and that the First Order was, to an extent, measured more by their technological capabilities rather than simply their overall size.
It should be noted that this article compares the First Order to the New Republic. This is not necessarily the same as comparing the First Order to the Resistance.
Answer: In TFA, somebody (I don't remember who) talks about how the First Order is more powerful than the Empire. It is logical to assume that the First Order is the same size, if not bigger, than the Empire
Comment: Welcome to SFF.SE! I'm not sure the logic is correct here, though. The First Order may be considered more "powerful" on the basis that it has the Starkiller Base, which is more powerful than even the Imperial Death Stars. But that doesn't mean the First Order is larger in terms of total members and systems controlled.
Comment: That's a logical fallacy. Size isn't everything. The USSR is bigger than the USA, but they aren't more powerful.


Mathematical methods for analysing melodic contour?

Question: Are there any mathematical methods for identifying melodic shape, identifying motifs and general pattern recognition?
Comment: Perhaps this addresses the idea, http://dmitri.mycpanel.princeton.edu/sciencearticle.html
Comment: Almost all of music theory is ultimately concerned with numbers in one way or another, albeit often disguised...
Comment: I have worked on this issue in the other direction, i.e. generating convincing melodies using a set of mathematical principles. That was difficult but feasible. The other way around, i.e. what was asked in the question, seems to me impossible without making a number of a priori assumptions that in turn would make the result not too interesting. In other words, if you want to analyze music mathematically, you will only discover what you already know.
Comment: @MicrologusSupport I get what you're saying, instead of analysis let's say we want to express our analysis mathematically? Can that be done?given that melodies, more often that not, contain patterns.
Comment: @AmanTrivedi Yes, you can definitely use math, statistics, graphics, charts, and so forth to express your musical analysis. And in this way you may be able to highlight certain aspects that are otherwise difficult to express. And seeing certain mathematical and statistical aspects may stimulate some original insights and stimulate new ideas. So it can help a lot from certain points of view, why not. But even in all these cases, the real work ,the real added value, comes from your own mind, from your own musical intelligence. IMHO
Comment: Totally agree with the last statement! I'm currently invited to give a presentation at a high school about music and decided to highlight certain mathematical aspects of music, mainly regarding patterns and how repetition of sequences can be linked to melodies. It's really annoying after a certain point because, as you said, there's no way (that I can see at least) that the patterns within a melody can be quantified as well as a arithmetic or geometric sequence.
Answer: You might be interested in checking out "Relating Musical Contours: Extensions of a Theory of Contour," a highly influential article in the study of musical contour. As a brief introduction, they consider a cseg (contour segment) to be an ordered representation of a musical line; <502314> is the cseg of the following excerpt:

(In short, you just take the available pitches, order them from lowest to highest starting on 0, and then list each pitch's placement. See the discussion of "c space" in the article.)
From there, you can then relate contours through constructions of matrices:

There's much more to it than that, but hopefully that whets your appetite if you're interested in studying further.
Since this sounds like it's for a high school lecture, you may want to stop there; the math in that article isn't rough at all. But if you're interested in getting into some more advanced math (or just checking out what else is available), I'll also recommend "New Directions in the Theory and Analysis of Musical Contour" and "Fuzzy Extensions to the Theory of Contour."
Answer: You actually should consider checking out the work of Guerino Mazzola and Jan Beran. Both come from Switzerland and seem to have a different approach. Jan Beran teaching at University of Konstanz nowadays, was studying records of different people playing one piece of music and was using analytical methods to study how a piece would sound. Guerino Mazzola seems to concentrate more on how the theory works and is using more algebraic methods to describe music.
"identifying melodic shape, identifying motifs and general pattern recognition" is a question of data analysis and data science, which is using different data sets. So yes, of course, something like this does exist with the right underlying statistical model. Maybe you can find some statistical models in Jan Beran's Statistics in Musicology.


Mounting a TV above a fireplace

Question: So, we have a 65" TV that we are thinking about mounting above our fireplace.   The fireplace is made of brick and has a wooden mantel.  Is it really a bad idea to mount the TV above the fireplace?   I mean obviously I know that heat doesn't do anything good for electronics but we would, at most, have gas logs in the fireplace.  I just wasn't sure just how bad an idea it was.  Thanks.
Comment: Heat rises. The TV will see more heat than it would elsewhere. There are numerous TV shows and others that have done it, and many reports from people online saying don't do it. You wont find many saying it was a good idea because it really isn't. @MichaelKaras nailed it. I have a 22x16' living room with a 8' brick fireplace. We investigated the same idea. Wound up installing it (75") on the wall next to the fireplace with a tilt&swivel extendable mount, it can take a nice angle and covers all seat area of the room. Best idea ever. The hard part was finding a short tv table for under it.
Comment: There exists a product designed to mount a TV over a fireplace mantel.  It's designed to solve some of the problems associated with this mounting place.  Now that you know it exists, maybe you can search for it on the Internet and find it.  The web site for the product has an FAQ and the installation manuals have advice on which fireplaces are suitable and which are not.  I can't say any more or else someone will think I'm trying to sell something instead of trying to help.
Answer: It is a bad idea. TV screens are designed to be viewed basically level from your eyes as you sit in your TV room. If you mount it above the mantel you will forever looking up to see the thing.
The heat thing is also a concern for electronics as you have mentioned. Raise the temperature some and in the best case you will age certain components and shorten the life of the TV.
You would also have to deal with the disfiguring of the brick face of the fireplace when you find that it is a less then optimal place for a TV and decide to take it down.
I fail to see why this is such a fad idea to put TV's up high on the wall.
Comment: I never understood the desire for this mounting location.  Why would someone want to strain their neck at all times.  I advise sitting on the couch and measuring your eye level.  Then, mount the TV's middle at that height or maybe 6" above that.
Comment: I agree with all of this. I have never understood why people do this. I've installed many like this for people and have always tried to talk them out of it. On a number of occasions, they'd had me come back to remove it.+
Comment: @Michael Karas - Meh, it really depends. At our last house we had the TV above the fireplace and it was fantastic. It frees up a lot of space in the room too. There was no neck strain and we had reclining seats so it was a great angle.  Plus, our TV is made such that you can angle it, so we angled it down a bit and that helped a lot.  As for the heat aging the components, we still have the same TV at the house we're in now, and the TV is 8 years old and still working fine.  We had gas logs, and a mantle, so that probably helped.
Comment: @EvilElf Its a convenient unused wall space.  Architects will design the room to make the fireplace an obvious focal point, but people also want the TV to be in the center of the room.  Layout wise, mounting a TV over a fireplace usually looks like the best option, but the height then kills the idea and makes it one of the worst locations to live with long term.
Comment: Coincidentally I just stumbled upon a subreddit that addresses your second sentence, [TV Too High](https://www.reddit.com/r/TVTooHigh/)
Comment: The heat may reduce the visibility of the screen as well. Hot air doesn't stand as still as air at room temperature. Think of the effect you see above hot asphalt in the desert sun, but less prominent.
Answer: It may not be desired, but sometimes it's the only available wall space in the room.  FYI, we mounted our 55" above the fireplace.  But the fireplace was converted to propane at the same time.  I was able to attach it to some paneling that was used to build the fireplace surround, after appropriate reinforcing.
Here's a picture of it completed.  Note that we have not had a problem with the viewing angle.

EDIT 1
I'm sure having the set recessed helps with the heat.  Samsung had all sorts of info in the mounting instructions as to when being above a fireplace would be an issue.
No, I haven't noticed much heat, if any, at the surface of the TV.
EDIT 2 - Answered question from Criggie
The two small panels on either side of the TV were the heatilator (?) outputs.  Fireplace itself is steel/iron plate.  So there's a cavity between the steel and the brick.  Intake vent on the bottom and exhaust at the top on both sides.  Strictly convection, no forced air (fan), so never got much heat out.  The one on the right hides the shutoff valve for the propane log insert.  The one on the left I used to route the FO cable from the box (which is on one of the shelves just to the left) to the TV.
The flat panel TV doesn't put out much heat at all, as all the processing and intelligence is in the (hidden) box.
Comment: Love The Frame TV.  I think the inset your TV sits in keeps much of the rising hot air off of it.  Do you ever notice if the TV gets _any_ additional heat from the fireplace?  I have vented gas logs and things above my mantle don't seem to get very warm at all.
Comment: The bigger the ledge, the more the niche will be isolated from the heat.   I wonder about the TV's own heat output at the top.  Also, what are the two squares behind the lower two corners of the TV - look like thin dado?
Answer: Good idea or not depends on several factors.
1) Is the sitting arrangement normally facing toward the fireplace and how close is the sitting area to the tv.  If the sitting area is close, then you would have the issues of the viewer looking up.  If the sitting area is across the room, then the angle of view to the screen is not that servere.
2) The type of chairs being used.  I have lounge type sofa that reclines, and having the tv up high is an advantage.  You should sit in the area where you plan to watch the tv and see if the height is appropriate for good viewing.
3) As others have stated, is there a heat issue that can cause problems.  Turn on the gas log, and check the temperature where you would mount the tv and see if there is a significant heat in that area.
If the viewing angle and heat is not an issue, if you do go this way, select a mounting system that allows you to tilt and rotate the screen toward the sitting area, so the screen is directed straight to the eye.
Comment: Hello, and welcome to Home Improvement. Thanks for the answer and keep them coming.

Mounting a TV above a fireplace


How do isolating VSO languages differentiate the subject and object?

Question: In some Austronesian languages, which typically lack inflection, subjects appear structurally identical to their objects. What constructs do Verb-Subject-Object languages use to distinguish the two?
Comment: Generally any way of marking the beginning or ending of a noun phrase so that the constituent boundary stands out will do when word order distinguishes arguments. Much the same perceptual solution occurs in English when speakers delete non-subject relative pronouns, leaving two NPs together as the signal for subordination, instead of needing a specific relative clause marker. I.e, _The car Bill saw was red,_ but not _*The car hit Bill was red._
Comment: Maybe it's just me, but can you elaborate a bit? I can't understand what you're talking about.
Comment: You mean besides word order? Quite a few Oceanic languages index their arguments on the verb, which is another way of differentially marking their grammatical relations.
Comment: In Austronesian languages, for instance, NPs are normally marked with terminal determiners (e.g, _itu/ini_ or _-nya_ in BI, which is, granted, SVO), and that serves to distinguish them. In Lushootseed (VSO, but emphatically not Austronesian), only one full NP can occur in a sentence, though there are many pronominal inflections that occur freely, and many verbal inflections that determine the role of whatever NP may occur.
Comment: Is all Indonesian considered BI (or Bahasa Indonesia)?
Answer: Prepositions are one obvious answer. English doesn't need to mark its object because of its SVO order, but it does mark most other roles with prepositions, and you can easily imagine a language that marks its subject or object with a preposition.
Of course I say "preposition" as that's what's typical in VO languages. In Japanese, a moderately synthetic language with some peculiar isolating tendencies, just about all roles are (sometimes optionally) marked with postpositions (Japanese is an SOV language). E.g. from "neko" (cat):
"neko ga": subject
"neko wo": object
"neko ni": indirect object
"neko kara": ablative
"neko ye": lative
In something of a variation on a theme, non-particle words may be used as well. E.g. some of Japanese' relational postpositions ("kara" comes readily to mind) are thought to originally have been nouns, probably the heads of agglutinative genitive constructs. In Trique, an indian language that was probably originally isolating, possessed-case nouns are often used to mark roles. E.g. "body of" can be an object marker (not often used, primarily for disambiguation), "face of" means "to", "hand of" means "from", "stomach of" means "inside", etc.
Alternately, you could use a serial verb structure to reduce a transitive construct to a pair of intransitive cosubordinated clauses. This is also common in Trique. E.g. to say "He said to them" you would literally say "Said he heard they". Though this isn't a very good example (off the top of my head) because both of those have an object of their own: the thing which was said, which comes at the very end.
Yet another method I can think of (though the examples I know of are pretty highly synthetic) is an agency-based system. In such a system, both subject and object are unmarked, and the more agentive noun phrase is taken to be the subject and the less agentive the object; if this is not true in a particular clause, an additional "exception" morpheme is added. If you look at the declension of Proto-Indo-European, there appears to be hints of a system like this, perhaps preceding the well-known PIE case system: specifically, you see that animate nouns were zero-marked in the nominative in some declensions, and inanimate nouns were zero-marked in the accusative.
Answer: Not a VSO language but SVO. Hopefully the principles are still illustrative of what would be possible also in a VSO language.
I've just discovered that Khmer has a particle which marks the direct object. I don't think it's compulsory as I just stumbled across it in a word frequency list and looked it up in a dictionary. I'll check my Khmer textbooks this afternoon.
នូវ
Two examples from the SEAlang Khmer dictionary:

ភ្នែកមានចក្ខុប្បសាទសម្រាប់មៀងមើលនូវរូបារម្មណ៌ដូចកែវយឹត។
The eye has a pupil which has the same function as a lens.
មនុស្សដែលធ្វើនូវអំពើល្អនឹងបាននូវផលល្អ។
A person who does good deeds will reap good results.


Which share icon is the right one? Or should it adapt?

Question: this is not a question regarding a particular problem, it's rather asking for your opinion. Let's say we have a website. It is not visited significantly more often by users of any of the fractions, so statistical argument should be left aside. Which share icon to use when grouping share options? Or maybe should it adapt to the OS user visits the site from? And can we transfer it anyhow to the desktop, so that users who got used to particular representation on mobile can see it also on desktop?
Comment: Related question has good info on grouping under a single share: http://ux.stackexchange.com/questions/10068/social-media-sharing-does-simply-showing-icons-stimulate-action
Answer:
Which share icon to use when grouping share options?

If sharing is important for your business, then use the sharing icons users will recognize. The faster a user finds her favorite social network icon, the likelier she will post the link. Any cognitive load, as in using unfamiliar icons, will decrease the willingness to share content.
That means that you should use the icons recommended on each social media. Share, tweet and pin it as long as the user gets what she expects while clicking the buttons. One example of how this could work, and be nicely grouped is Mashables' articles where sharing activities comes just below the headline but before content:

Or maybe should it adapt to the OS user visits the site from?

That is of course an option, but having real icons instead of the anonymous iOS share or an Android share icons are preumably better. And since this is mobile web, users more familiar with their own mobile web browser sharing buttons will use those instead. An exact duplicate icon on the web page could be confusing.

And can we transfer it anyhow to the desktop, so that users who got used to particular representation on mobile can see it also on desktop?

That's the tricky part, and what is the real argument for using the social medias recommended icons instead of iOS or Android icons. You will not be wrong using standard social media icons, but you could go wrong using iOS or Android icons. Safety first.
Answer: After reading this article I was wondering if there could be a single winner in the case of sharing in case someone wanted to represent it abstractly and to group all the share actions as you mentioned.
After some deep thinking on what sharing would look like, it does not seem to me like two children sharing a chocolate, referring to the icon where you have two hands. Nor is sharing whispering in someone else's ear; this is gossip.
Sharing is take something that is mine and has value and sharing it with a crowd. This is when the image of a person throwing something valueable like money to the crowd came in mind.

Therefore I must conclude the "Y" (old android) is the winner and the most suitable icon for sharing
Comment: I need an argument much stronger than just downvoting. I cannot find how much different, downvoting without explanation, is from bullying


Quantum representation of cube

Question: Let's say I have a square matrix of size $2^n\times 2^n$ with entries being 8 bit integers, where $2^n\times 2^n=b\times b\times b=2^l\times 2^l\times 2^l$, then if I want to represent that matrix in the form of a cube, is the following representation correct?
$$|A\rangle=\dfrac{1}{2^{3k/2}}\sum_{i=0}^{2^l-1}\sum_{j=0}^{2^l-1}\sum_{k=0}^{2^l-1}|A(i,j,k)\rangle\otimes |i\rangle|j\rangle|k\rangle,$$ where $A(i,j,k)$ is the value at the location $(i,j,k)$ and $|A(i,j,k)\rangle$ is the binary representation of the decimal value, and $|i\rangle,|j\rangle,|k\rangle$ are the position coordinates each of length $b$ bits. Can we represent the cube like this?
Comment: $2^9\times 2^9=2^6\times 2^6\times 2^6$, so here $b=64$,  yes binary representation means the binary of the number, for example, $7=|111\rangle $, associating a $ket$ with the binary representation, yes $A$ is the matrix with integer entries with each entry of $8$ bits.
Answer: To be clear, you essentially have a cube consisting of $2^l$ points along each direction, and associated with each point $(i,j,k)$ is an 8 bit integer $A(i,j,k)$?
In that case, a state of $3l+8$ qubits,
$$
|A\rangle=\frac{1}{2^{3l/2}}\sum_{i,j,k=0}^{2^l-1}|A(i,j,k)\rangle|i\rangle|j\rangle|k\rangle
$$
is one possible way of representing the data. It is very reminiscent of quantum fingerprinting schemes.
The real question is what you want to use such a representation for? That will determine if the representation is any good. What you cannot do is use single copies to deterministically extract information about the values of $A(i,j,k)$. This should be obvious - you cannot use $3l+8$ qubits to give you arbitrary access to $24l$ bits of data.
Comment: Yes that is the representation that i also wrote, except for the typo in the normalizing part. I didn't understand the last part of your answer?
Comment: Well, you question "Can I represent it like this?" is answered with a qualified "yes" (it contains all the data, but it depends on what you need to do with the data). I'm trying to check *why* you want to represent that data as a quantum state in order to determine if your chosen representation is any good for that purpose.
Comment: actually, i need this for information scrambling purpose.

Quantum representation of cube


Polyurethane finish over stained wood - can I combine brush and rub on techniques?

Question: I am finishing a coffee table with Polyurethane. Used it many times, but have never managed to completely eradicate those pesky brush marks on the final finish, despite sanding between coats.
So this time I am considering using the rub on method.
Obviously being a coffee table it's going to get heavy use, so would need many many coats.
Can anyone tell me if I can do the first couple of coats using a brush, sanding between coats to get it smooth, and then switch to the rub on method with thinned poly to get a perfect finish?
Comment: more coats isn't always better.  Too many coats could lead to cracks in your poly layer.  Follow the manufacturer instructions.
Answer: I wouldn't recommend using a bristle brush at all. Use either a foam brush or a lambskin applicator. I don't really see a reason to switch between the two, but it should be ok.  Make sure you follow the manufacturers recommendations.  You do not want to begin sanding until the solvents have evaporated and it begins curing.  Also, time between coats has an upper limit.  See the manufacturers website.
Two additional thoughts:
You can use a thinner such as mineral spirits to thin out the polyurethane.  You will need more coats, but it will help eliminate stroke marks.
If you really think a small application like a coffee table will take that much abuse, you could use "Glaze coat". It is a two part that goes on extremely thick and works very well.  Commercial bar tops and table tops often use it. It's not cheap.  Last time I used it I paid $25 for 9SF of coverage, but it goes on smooth and when you are done you could practically weld on it ("slight exaggeration")
Answer: I use very expensive brushes with poly and always have good results, I am talking brushes in the 15-20$ range. I have never had much luck with anything else. After done I clean most of the poly out then put the brush in a jar full of spirits and seal until next time. The problem I see from DIY folks is they try two hard to work the poly it starts to dry and the brush strokes stay. I prefer brushing over rubbing rubbing will take 5x the coats to get the same depth look. I would work on your method of application, no more than 3 strokes reload and apply more. Thinning down the poly can make applications easier but you need more coats. Don't go cheap on your brushes this has a large impact on how the poly is evenly distributed.


Remove Vertical Scroll in Page Viewer web part viewing a Folder

Question: A Page Viewer web part was added to a page. The Page Viewer points to a SharePoint library folder. The folder and its contents are viewed in the IFRAME, but the box has a vertical scroll. I've tried everything to hide, including adding a "overflow:hidden;" css mod, didn't work. Ideas?
edit: meant to say "hide the vertical scroll"
Answer: The scrollbar comes from within the iframe and is therefore inaccessible by CSS on the hosting page.
You can, however, add some JavaScript to the page that is shown in the iframe, that checks the value of a custom parameter in the querystring and adds your overflow:hidden accordingly.
JSRequest.EnsureSetup();
if(JSRequest.QueryString["scrollbars"] == "false"){
    ... remove scrollbars
}

In your iframe configuration you pass the scrollbars parameter with value false to the page.
For example:
https://.../AllItems.aspx?scrollbars=false


Coveo error when accessing index manager: No SecurityProviderConversionHelper found for index: Coveo_master_index

Question: I've installed Coveo (pro cloud edition with the October 2016 package), and after installation I went and changed the farm name and Sitecore account it was using (the account I switched to is still an administrator account). When I tried to access the diagnostic page, I got a YSOD message with "No SecurityProviderConversionHelper found for index: Coveo_master_index." Looking around, I thought it could be because I hadn't kicked off an initial index yet, but when I go to the indexing manager, I get the same error. I don't see this message around the developer or answers sites on Coveo, so assistance appreciated.
Answer: It is a bug introduced with the October package (4.0.450) happening when upgrading and changing the Sitecore account. We are looking for solutions on our side.
Comment: Thanks - I submitted a ticket like we discussed on Slack, so I should be in the system now.
Comment: Hotfix confirmed to be coming soon, will post the link when it's done for folks to know about.
Comment: Should note, Coveo sent me a hot fix for the issue, but has also updated the October release to version 704, which should resolve this issue.
Answer: Did you synchronize after you changed the farm name? You could also do a reindex or a publish.
But I recommend you making sure the configs look good, followed by doing a security cache flush and synchronize.


Problems Downloading Server 12.10

Question: I've been trying to download the ISO for Server 12.10 amd64 for a week now.  None of the MD5 checksums match the posted values.  I am not having any problems downloading from other sites, and I've tried the download from multiple computers.
Answer: The MD5sum of the server file is 4bd3270bde86d7e4e017e3847a4af485 *ubuntu-12.10-server-amd64.iso and the .ISO is found here http://releases.ubuntu.com/12.10/ubuntu-12.10-server-amd64.iso
according to http://releases.ubuntu.com/12.10/
Answer: Try torrenting the files from the .torrent files on the site.  The BitTorrent protocol has built in file checking, so your likelihood of a corrupted download is much lower - plus, file download speeds will most likely be faster!

Problems Downloading Server 12.10


What is divergence?

Question: What is divergence? I was learning about Maxwells equations and don't understand the divergence part of it. Can someone give an intuition of what divergence is in relation to maxwells equation. To give you a sense of language to use I'm 17 and don't do maths or physics at school (I've just recently started loving the two.)
Comment: Wow, I just looked up the Wikipedia page and there isn't a single picture to give the reader intuition. That's depressing.
Comment: The divergence of a vector field is the infinitesimal relative change in volume when transporting a volume element along its flow. The abstract definition in terms of Lie derivative and volume form is quite intuitive here.
Comment: @DanielSank: Add one, don't complain.
Comment: The word itself is quite descriptive. A common definition is the measure to which a vector function spreads out ("diverges"). If you're familiar with differentiation of scalar functions (df/dx etc.), divergence is one of the derivatives of vector functions and shouldn't be that much of a mental leap.
Comment: So wrt Maxwell's electrostatic equations in differential form,  the divergence of the electric field is proportional to the charge creating the field or in integral form the charge "enclosed" by a surface.
Comment: @NikolajK: Indeed.
Answer: Divergence is an operation that maps a vector field $\vec D(x,y,z)$ to a scalar field ${\rm div}\,\vec D(x,y,z)$. How do you calculate ${\rm div}\,\vec D(x,y,z)$?
Either you follow the definitions using derivatives, which you can't if you don't know what a derivative is.
Or you imagine the following: the vector field $\vec D(x,y,z)$ tells you about the direction where something (water) is flowing, and how quickly it is flowing. Effectively, at each point $(x,y,z)$ in space, the magnitude of the vector (recall that a vector is a number combined with the arrow remembering a direction) tells you how many liters of water flow through the surface (orthogonal to the arrow) per second.
To visualize the divergence at a given point, draw a small box (or sphere or any shape) around the point and look how many liters are getting in and getting out of the box per second. Because the vector field is slightly different on opposite sides of the box, the amount of water that gets in from the "top face" of the cube isn't quite the same as the amount that gets out from the "bottom face", and similarly for the other four faces of the cube.
This results in some imbalance – the water is really accumulating or disappearing from the cube. And the divergence ${\rm div}\, D$ is how many liters of the water are being added per second and per unit volume of the cube (the larger cube, the more). It is negative if the water is disappearing.
Water can't really get lost or appear. So maybe I should have talked about some gas which may accumulate or disappear (increasing/decreasing pressure) for a while.
In result, the divergence is positive at points where you have "sources" – the arrows of the vector field are mostly "outgoing" – and negative at points where you have "sinks" – the arrows are mostly "incoming".
The Maxwell equation for $\vec E$ or $\vec D$ tells you that the arrows of the electric field must be mostly "leaving" from the electric charges of one sign, and "arriving to" the charges of the opposite sign. The discussion above is inevitably vague and qualitative. To know what the divergence is quantitatively, you really have to learn something about derivatives etc., but it's not so hard!
Comment: Yes, divergence is what matters the sink-like or source-like character of the field lines around a given point, and it is just 1 number for a point, less information than a vector field, so there are many vector fields that have the divergence equal to zero everywhere.
Comment: So basically, divergence is zero if there is no source or sink whatever the shape of electrostatic field lines?
Answer: Taking your (lack of) knowledge about differential geometry into account, this might be too hard to follow, but here it goes anyway:
Let $u_1,\dots,u_n$ be some tangent vectors with base point $p$ and $\omega$ the volume form, ie $V = \omega_p(u_1,\dots,u_n)$ is the (possibly negative) volume of the parallelepiped spanned by these vectors.
In case of three dimensional Euclidean space, this is just the triple product
$$
\omega_p(u_1,u_2,u_3) = u_1\cdot(u_2\times u_3)
$$
Now, let $X$ be a vector field (eg the electric or magnetic field) and $\varphi$ its flow, ie $p'(\epsilon) = \varphi^\epsilon(p)$ is the point you arrive at when moving along the field lines of $X$, starting at $p$ and with 'velocity' given by $X$ and 'time' given by $\epsilon$.
This maps the tangent vectors at $p$ to $u'_k(\epsilon) = \mathrm T\varphi^\epsilon(u_k)$ at $p'(\epsilon)$. Here, $\mathrm T\varphi^\epsilon$ is the tangent map of $\varphi^\epsilon$ (a kind of multi-dimensional derivative); in coordinates, it is given by the Jacobian matrix.
The volume of the parallelepiped will change from $V$ to
$$
V'(\epsilon) = \omega_{p'(\epsilon)}(u'_1(\epsilon),\dots,u'_n(\epsilon))
\equiv (\varphi^{\epsilon*}\omega)_p(u_1,\dots,u_n)
$$
The divergence at $p$ is the limit
$$
(\mathrm{div} X)(p)= \lim_{\epsilon\to 0} \frac{(V'(\epsilon) - V)/V}{\epsilon}
$$
ie the infinitesimal relative change in volume when transporting a volume element along the flow of a vector field.
The equivalent formal definition in terms of Lie derivative $\mathcal L_X$ reads
$$
(\mathrm{div} X)\,\omega = \mathcal L_X\omega
$$
I also cobbled together an image that might or might not help get the point across:
Comment: Wow! This a very good answer. Thanks so much.
Answer: Here's a derivative-free explanation.  For readers who are doing E&M at the college level, the other answers posted here are more comprehensive, but since the OP has stated a high-school knowledge with little math and physics knowledge, here's the primer:
A vector is a quantity that, in order to be fully measured and described, needs to include both a magnitude (size) and direction.  In Electricity and Magnetism, many quantities such as electric field and force are vectors because not only do you need to describe the size of these measurements, but also the direction that they act in.  Fields like electric fields or magnetic fields change, based on your location.  If an electric field is being produced by a point charge, the strength of the field at a given location will depend on how close the charge is to that location.  However, depending the direction that the field points will also change based on your location.  Divergence is way of measuring how much electric field "spreads out" at a given location.

The picture above shows vectors represented as arrows.  This could represent the electric field generated by a single negative charge located at the origin.  You can see the way the vectors "spread out," or the angles made by the tip of nearby vectors changes as you move around the field.

As a trivial example, if all of the arrows had the same magnitude, and pointed horizontally to the right, like in the picture above, there would be no divergence because the vectors do not "spread out."
Comment: Much easier to think in terms of field lines. Divergence occurs where field lines begin or end.
Comment: The spreading out thing doesn't work either. If you had a field going normally from vacuum into glass, it would look similar to your last picture but the field would be weaker in the glass (but going in the same direction). There is a divergence of the E-field at the interface, but the E-field vectors do not spread out.
Answer: The two maxwell equations using divergence are
$$ div \vec{D} = \rho \\
div \vec{B} = 0 $$
at least in differential form. In integral form they are maybe more clearer for you. They are
$$ \iint_{\partial V} \vec{D} \ d \vec{A} = \iiint_{V} \rho \ dV = Q(V) \\
\iint_{\partial V} \vec{B} \ d \vec{A} = 0$$
The first equation just means the electrical flux $D$ through a close surface of a volume $V$ is proportionate to the electrical charge in this volume. Or in much simpler word, divergence is a mathematical measure of the density of your electrical flux so you can make conclusions of the number of electrical charges. To be a little more precise. The electrical field is something coming out of sources (positive charges) and ends in sinks (negative charges). So if you include just one source with your volume $V$ and a sink is somewhere out of your volume your divergence measures one positive charge $Q$. If your volume include two sources and a sink you will measure again just one positive charge $Q$.
The second equation is the same but with magnetic flux. You will notice the equation is always 0. This is because there are no sources or sinks in magnetic charges, so the divergence of $\vec{B}$ must always be 0.
Answer: As it looks like another question I've supplied an answer to might be duplicated here (and hence closed), I am going to provide a similar but not identical answer here.
In words - divergence is the flux of something into or out of a closed volume, per unit volume.
The best visual picture I have of this is a fluid flow. Imagine water spewing out of a tap - this has positive divergence; the tap is a source of the flow (density times velocity) of the water. Conversely you could imagine water dropping down a plug hole. The flow at the plug hole would have negative divergence because it is a sink of the water flow.
But now you want to deal with Maxwell's equations and electric and magnetic fields. You are probably familiar with the idea the electric and magnetic fields can be represented using "field line diagrams"? Here are field line diagrams for the electric field from isolated positive and negative charges respectively.

In the field line representation, regions of positive or negative divergence are places where field lines either begin or end respectively. For the positive charge, you can see that field lines originate on the charge and spread outwards. The divergence is positive at the charge. At all other points in space around the charge, the field lines are continuous and the divergence is zero. This is the slippery bit of the whole concept, because it is not when you have diverging field lines that you have a positive divergence! It is when the field lines begin. This fully agrees with what Maxwell's equations tell us - that the divergence of the electric field at a point is proportional to the charge density at that point.
The case for the negative field lines is analogous. Here though the divergence at the negative charge is negative, because the field lines are ending there. The divergence in the space around the charge is zero.
Now have a look at this plot of the field lines due to a magnetic dipole (this is a bit like the fields produced by a bar magnet or a current flowing around a loop of wire.

Notice that in this diagram, the lines of magnetic field are continuous; they have no beginning or end (the ones leaving the edge of the picture eventually join up with the ones coming back into the picture). Thus the divergence of this field is zero everywhere. Again, this is what Maxwell's equations tell us - that there are no sources or sinks of magnetic field (no magnetic monopoles) and that the divergence of the B-field is always zero.

What is divergence?


White Dust: Is it bad for electronic devices like smart TVs or phones?

Question: As a side result of using an ultrasonic air humidifier, this white dust thing can be seen on house furniture during its activity. I googled about it but I only found a few articles, saying that it is safe for human body but I found nothing about house devices. Does it have any bad effect on my LED TV? I use a homemade cover for it but, I'm still kind of worried.
Comment: I would not trust the web regarding human safety. Worry about yourself before you worry about your possessions. Use distilled water in the humidifier (buy at local drug store) .... as far as safety for electronic devices, probably not safe if water contains dissolved salts. No idea about other minerals, but i guess that any iron content could cause degradation in electronics performance.
Comment: If you're covering your TV, I'd be concerned about it overheating due to lack of airflow.
Comment: @jwygralak67 Hi there, I'm not using cover when TV is on. Usually, I try not to use humidifier when the TV is on.
Answer: White dust:
https://www.hvac.com/faq/white-dust-concerned/

White dust is usually caused by mineral content in the water that goes into a humidifier. When the mist lands on furniture or other surfaces and dries, it can sometimes leave behind the dried mineral deposits, or "white dust".

The dust is a salt (ionic compound).
The dust should be safe when dry, but as soon as it absorbs moisture it will become electrically conductive.
I would be more concerned about the liquid water that appears before the dust.
You could use distilled water as suggested by @jsotola to avoid the issue altogether.

I was wondering for myself a moment why "normal humidity" doesn't cause the white dust, but only the humidifiers do:
Ultrasonic humidifiers work by splashing water everywhere, the same thing you can do with your arms in water, the only difference being the size of the droplets.
So you should definitively use distilled water as the humidity from an ultrasonic humidifier is basically like splashing water on electrical appliances.
Tiny droplets of distilled water shouldn't be much different from normal humidity which generally isn't an issue.
Comment: Tiny drops of water are still that, drops of liquid water. Humidity in the air is different, it is not liquid. The tiny drops will conduct and depending on the circuit damage it
Comment: @Oslar Skog Hi there, You wrote: "I would be more concerned about the liquid water that appears before the dust." Is it wet when it's being absorbed to the surface or is it just dry dust that is absorbed to surfaces due to its ionized nature? I'm asking this because there's a considerable distance between humidifier device and TV that makes me think that it must become dried out before reaching TV surface or am I wrong?!
Comment: The article suggests that the water dries up and leaves the white dust behind, so I assume it may be humid when adsorbed to surfaces.   But I don't know.
Answer: Ultrasonic humidifiers have a way of vaporizing that causes the lime sediment in water to evaporate and condense on any nearby surface unlike steamer and spin drum (hot & cold types) .
A demineralization water filter can work.
Lime can be harmful , long term , to lead solder joints in copper plumbing, so water softening is recommended to remove the minerals. Boiling water will also leave a white sediment in kettles, coffee boilers and cooking pots, according to how "hard" the water is.
Lime is not conductive or very salty as far as ionic levels are concerned so it will be harmless when dry.
Comment: _Evaporating_ lime would be impressive. In reality, dust is created when an impure water droplet evaporates, leaving a small speckle of dust behind.
Comment: It is the corrosive stuff on copper pipe solder joints caused by hard water and prevented by a water softener.. Perhaps it depends on location but I was thinking of calcite from limestone
Answer: The most practical and economical solution I have found to the problem of minerals depositing on my electronics while I run the ultrasonic humidifier was to buy a small, very affordable water distiller.  It can produce a gallon of distilled water every 4 hours (which in my case is enough to run the humidifier for a little over a full day), while using just under 3kW of power (which cost around 20 cents where I live).  This avoids buying and tossing plastic jugs of distilled water, which cost about 2 bucks a gallon.
The small, positive side effect of running the distiller is that during operation it releases heat, so I run it in the morning, after I leave for work, while the noise doesn't disturb anyone in the family, and sort of heats up the room a little in the meantime.  It shuts down automatically when it's done.  When I get home in the evening, I have a gallon of distilled water, which I mix ~50/50 with tap water.  With only half of the minerals in the humidifier as I would with 100% tap water, the built-in de-mineralizing cartridge/filter does a great job at completely eliminating the white dust.
Comment: I have to recognize that the only reasons I wrote my reply as an answer and not a comment, is that 1) there's no answer-fits-all, as dust-conductivitiy depends on the composition of the minerals dissolved in each household's water (usually calcium and magnesium, but there's a lot more to it), and 2) I didn't have enough "credit" to write comments.
Comment: Welcome to Stack Exchange Electrical Engineering! This is useful information, but it doesn't answer the question of whether the 'white dust' is bad for electronics. (note: I'm _not_ the anonymous coward who downvoted you without any explanation)
Comment: @BruceAbbott It does not answer the question but does provide an alternative so that the question need not arise. Upvoted. Personally I *would* be bothered about breathing stuff dissolved in tap water, irrespective of its effects on electronics


Is it possibly to remarry my wife after three talaqs?

Question: I was married with my ex-wife for 18 years. Before we got married my ex-wife was pregnant. As it was a void one, I gave talaq and remarried her once again. Subsequently, we were living happily until we encountered some differences and again I gave talaq. Subsequently we remarried again and was stable for sometime. Finally in 2012 I gave talaq again. I want to remarry her. However we have had technically 3 talaqs; my question is whether it is possible to marry her without her marrying another person?
Comment: Salam and welcome to Islam SE. Please consider taking your time to take our [tour] and check our [help] to learn how this page works. You should know that there's no way out of this as Quran is crystal clear about the 3rd talaq http://legacy.quran.com/2/229-230
Answer: Short answer - consult a scholar, otherwise advice by lay people may affect your marriage!
In a nutshell, as you have given three talaqs, you are technically divorced. Its not possible to marry her without her marrying another person. This is the severeity to enable people to understand that their actions will be accountable.
Comment: I strongly suggest you to add an evidence to support your claims (see [answer])!


How can I make a warning sign appear when an enemy is behind my character in game engine?

Question: I have a First person shooter game with enemies that are constantly seeking my character. How can I make a warning sign appear when an enemy is behind me? I have tried the near sensor, but it didn't work.
Answer: The near sensor is checking if an object is near.
You requirement is to detect if the enemy is behind the character. Either you use a radar (looking behind the character), or you use the near and check if the detected objects are behind the character.
Nevertheless the near sensor should detect objects already. Are you sure the enemies are in range and detectable (dynamic, or rigid body)?


Spotify opens a new window when you click on the sound tray menu [Loki]

Question: When you use new Loki's Menu to control Spotify, and click on the spotify song, a new window opens each time you click instead of bringing the existing window to the foreground.
see here:   http://i.imgur.com/RBYDbee.gifv
Answer: This application acts against common expectations, so I'd consider it a bug. Please subscribe to the bug report here so that the devs can ask for help testing solutions. If you want to give the open source devs some extra incentive, try putting a developer bounty on the task.


Post apocalyptic novel, one character a centaur with a mouth in the middle of its chest

Question: I read this when I was a kid, so some time in the 80's, may have come out earlier, though. I don't remember that much about it, other than that it was set in a post apocalyptic earth (I think United States, for some reason I've got California in my mind) where forest and wildlife has overgrown all civilization. There's a group of characters on an adventure. I think they are mostly mutated in various ways. One of them is a centaur-like creature. He has a horse body, and a human head and face and mouth, but he eats (mostly fruit) with a mouth that's in his chest. They keep finding "artifacts" that they find mystifying, but you as the reader can identify as various bits and pieces of technology, like a road sign, or a can opener.
Answer: Dark is the Sun by Philip Jose Farmer.
The centaur like being with a mouth in his chest is an Archkerri called Sloosh:

What was not familiar was the creature that had disturbed the beetles. The thing was huge, its head three feet higher than Deyv's. It had four massive legs ending in broad round pads. The body was shaped like a bean pod. That is, the main body was. From its front a trunk reared at a right angle. This was shaped
  like the torso of a man and had shoulders, two arms, a neck, and a head. The  hands had a thumb and four fingers.

As you say, the Archkerri eats fruit through a mouth in it's chest, though it will eat meat as well:

Still, the time Sloosh took in finding and eating food continued to be a trial to Deyv. The Archkerri's mouth was concealed beneath the leaves on the "chest" of the upper body. Finding that out had been a shock to Deyv. It had seemed grotesque and also a little frightening. His grandmother had told him about
  a monster which was human-shaped, unlike Sloosh, but which had its mouth on its breast, and its diet was confined to human children. As a child, Deyv had been threatened with it when he didn't behave.
Sloosh would eat meat, including the rottenest carrion, when it was available. But mostly he ate fruit and vegetables, and he required great amounts of these. To speed up the search for food, the two humans would forage the edge of the jungle. They'd woven some large baskets from reeds, and they used them to store the fruit. Thus, they could walk faster, feeding Sloosh from the baskets. But collecting the food took much time, too.
Comment: When this book came out, I was a Farmer fan. This book ended that. It's one of the worst books I had read up to that point. My brother and I always referred to it afterwards as *Bad Is The Book*.
Comment: THAT'S IT!!!  Thank you so much!
Comment: John, a quick opinion on the book? Is it worth reading?
Comment: @motoDrizzt: it's a long, long time since I read this so my memory of it is a bit vague. My recollection is that it's entertaining but no great work of art. I wouldn't put it on the *must read* list.
Answer: This may be Hiero's Journey, by Sterling Lanier.  I don't remember a centaur, but there is a mutant moose.  Per Wikipedia:

The novel follows the adventures of a priest by the name of Per Hiero Desteen as he explores the mutant-infested wilderness of Canada and North America five millennia after an event called The Death destroyed civilization. Riding a mutant moose named Klootz, with which he is able to communicate telepathically, Hiero attempts to uncover what has become of some colonies that his abbey has attempted to establish. Hiero's eventual allies include Gorm, a telepathic black bear, and Luchare, a princess from the distant kingdom of D'alwah. On his journey he faces many dangers, including mutated humans, mutant beasts, and the evil forces of The Brotherhood of the Unclean

An excerpt from online:

The Computer Man, thought Hiero. That sounds crisp, efficient, and what's more, important. Also, his negative side added, mainly meaningless as yet.
Under his calloused buttocks, the bull morse, whose name was Klootz, ambled slowly along the dirt track, trying to snatch a mouthful of browse from neighboring trees whenever possible. His protruding blubber lips were as good as a hand for this purpose.
Per Hiero Desteen, Secondary Priest-Exorcist, Primary Rover, and Senior Killman, abandoned his brooding and straightened in the high-cantled saddle. The morse also stopped his leaf-snatching and came alert, rack of forward-pointing, palmate antlers lifting. Although the wide-spread beams were in the velvet and soft now, the great black beast, larger than any long-extinct draft horse, was an even more murderous fighter with his sharp, splayed hooves.
Hiero listened intently and reined Klootz to a halt. A dim uproar was growing increasingly louder ahead, a swell of bawling and aaahing noises, and the ground began to tremble. Hiero knew the sound well and so did the morse. Although it was late August here in the far North, the buffer were already moving south in their autumn migration, as they had for uncounted thousands of years.
Morse and rider tried to peer through the road's border of larch or alder. The deeper gloom of the big pines and scrub palmetto beyond prevented any sight going further, but the noise was getting steadily louder.
Hiero tried a mind probe on Klootz, to see if he was getting a fix on the herd's position. The greatest danger lay in being trapped in front of a wide-ranging herd, with the concomitant inability to get away to either side. The buffer were not particularly mean, but they weren't especially bright either, and they slowed down for almost nothing except fire.
The morse's mind conveyed uneasiness. He felt that they were in the wrong place at the wrong time. Hiero decided not to delay any longer and turned south off the trail, allowing Klootz to pick a way, and hopefully letting them get off at an angle to the oncoming buffer.

....

The Taig, the vast boreal forest of conifers which had spread across the northern world at least a million years before The Death, still dominated the North. It was changed, however, with many species of warm country plants intermingled with the great pines. Some plant species had died, vanished entirely, as had some animals also, but most had survived, and adapted to the warmer climate. Winters were now fairly mild in the West of Kanda, with the temperature seldom ever getting below five degrees centigrade. The polar caps had shrunk and the earth was once again in another deep interglacial period. What had caused the change to be so drastic, man or nature, was a debated point in the Abbey classrooms. The Greenhouse Effect and its results were still preserved in the old records, but too much empiric data was lacking to be certain. Scientists, both Abbey and laymen, however, never stopped searching for more data on the lost ages in an effort to help shape the future. The terror of the ancient past was one thing which had never been lost, despite almost five thousand years. That The Death must never be allowed to come again was the basic reason for all scientific training. On this, except for outlaws and the Unclean, all men were agreed. As a good scientist and Abbey scholar, Hiero continually reflected on the problems of the past, even as now, while seeming to daydream in the saddle.
He made an effective picture as he slowly rode along, and not being without vanity, was aware of it. He was a stocky young man, clean-shaven but for a mustache, with the straight black hair, copper skin, and hooked nose of a good Metz. He was moderately proud of his pure descent, for he could tell off thirty generations of his family without a break. It had come as a profound shock in the Abbey school when the Father Abbot had gently pointed out that he and all other true Metz, including the abbot himself, were descended from the Metis, The French Canadian-Indian half-breeds of the remote past, a poverty-stricken minority whose remoteness and isolation from city life had helped save a disproportionate number of them from The Death. Once this had been made clear to him, Hiero and his classmates never again boasted of their birth. The egalitarian rule of the Abbeys, based solely on merit, became a new source of pride instead.
On Hiero's back was strapped his great knife, a thing like a short, massive sword, with a straight, heavy back, a sharp point, a four-teen-inch rounded blade, and only one edge. It was very old, this object from before The Death, and a prize won by Hiero for scholastic excellence. On its blade were incised, in worn letters and numbers, "U.S." and "1917" and "Plumb. Phila.," with a picture of a thing like an onion with leaves attached. Hiero knew it was incredibly ancient and that it had once belonged to men of the United States, which had long ago been a great empire of the South. This was all he or perhaps anyone could know of the old Marine Corps bolo, made for a long-lost campaign in Central America, forgotten five millennia and more. But it was a good weapon and he loved its weight.
He also carried a short, heavy spear, a weapon with a hickory shaft and ten-inch, leaf-shaped steel blade. A crossbar of steel went through the base of the blade at right angles, creating what any ancient student of weaponry would have recognized at once as a boar spear. The cross guard was designed to prevent any animal (or human) from forcing its way up the spear shaft, even when impaled by the spear's point. This was not an old weapon, but had been made by the Abbey armory for Hiero when he had completed his Man. Tests. At his saddlebow was holstered a third weapon, wooden stock forward. This was a thrower, a muzzle-loading, smooth-bore carbine, whose inch-and-a-half bore fired six-inch-long explosive rockets. The weapon was hideously expensive, the barrel being made of beryllium copper, and its small projectiles had to be hand-loaded by the small, private factory which produced them. It was a graduation present from his father and had cost twenty robes of prime marten fur. When his stock of projectiles was exhausted, the thrower was useless, but he carried fifty of them in his pack; few creatures alive could take a rocket shell and still keep coming. A six-inch, two-edged knife, bone-handled, hung in his belt scabbard.
Comment: Don't seem to remember any centaurs in that book.
Comment: I found a copy at http://www.e-reading.club/bookreader.php/1010149/Lanier_-_Hieros_Journey.html, dubious legality, if you want to check.


subdivided/unsubdivided linked split screen

Question: Is there a way to split the viewport so I can view my unsubdivided model in edit mode and my subdivided model in object mode at the same time? I'd like to be able to edit my mesh and see it update on a subdivided version on a separate window. Thanks!
Answer: A trick to do that :

Temporary use a mirror (1) with another object as center, here an empty (2).
You can edit the original and see the mirrored mesh with subsurf.
When finished, remove or hide the mirror modifier.
Just remember that the shape is mirrored... so the left becomes the right, etc.
From that you can set two views in order to choose the rendering mode for each:
Comment: @Matt. The last screen capture shows the mesh with subsurf (left) and without (right) in two separated views... so I dont understand your comment ?
Comment: @Matt, In fact I dont know why I did not thought about the solution you propose... but fortunately, the mirror approach leads to no live update problems...
Comment: This is not quite what the OP is asking for. They want to see their mesh with, and without subsurf at the same time (in different panels).
Comment: oh! I didn't notice that the subsurf was above the mirror modifier. I retract my critique. That's genius!
Comment: I know this is an old thread, but this is indeed an ingenius hack :). Very cool.
Answer: Unfortunately, no there's not a way to do exactly what you're looking for.
There are some workarounds, though. One possibility has been mentioned by Lemon.
Another option is to create another object with a linked mesh. You can do this either by selecting the original and then pressing Alt D. This will make a duplicate object that uses the exact same mesh. In fact, if you change the mesh in one object, it will update in the other. For more information on that, and other methods of doing the same thing, check out the Duplication Section in the Manual.
Once you get them linked, you could remove the Subsurf from one of the objects, and leave it on the other. Then, edit the mesh that doesn't have a Subsurf, and you'll see the changes on the one with Subsurf. You could even go to the point of having two 3D Views, one of them focused on one mesh, and the other focused on the other.
Note: Sometimes updates happen live in edit mode, but sometimes they don't propagate to the other objects until you leave edit mode. Either way, this is probably as close as you can get in Blender.
Answer: You can create a new 3d view window and under the Tools panel (N hotkey) / Display check Only Render. This will make that view only show the final mesh.
Comment: Ahh I see. Well my current suggestion then after experimenting is to duplicate linked (Alt+D) shortcut key. The 2nd mesh will update from the 1st mesh, **however** it only works in object mode. So you have to toggle back and forth with the tab hotkey.
Comment: This is not actually the case. From the Manual: "While the option displays the regular view-port without distracting elements, the objects displayed **are not matching the final render output.**

Options such as restrict-render, **modifiers render option,** dupli-parents and render layers are **not taken into account.**"
Comment: https://www.blender.org/manual/editors/3dview/display/panels.html
Comment: Lol, great minds think alike.


Kosher wines and agricultural laws of the Torah

Question: I write an article about kosher wines and ask for help. Tell me, in the production of grapes, the agricultural laws of the Torah operate only on Israeli soil? If in another country the wine producer wants to produce kosher wine, should he comply with them? I'm talking about the laws of the Orlah, Shmita, Ma'aser, Kilayim. Since when can only a Jew touch the grape? From the moment of harvesting or from the moment of entering the grapes into the wine press? Can a Jew trust not Israeli producers of kosher wine?
Comment: Are you asking only about Torah law, or Rabbinic law as well?
Answer: If you're writing an article, the best thing to do is speak to a real-life expert. I'd recommend calling the Orthodox Union, Star-K, or the like and they should be able to put you in touch with someone actually responsible for certification. (Or if you want a more European angle, try the London Beth Din.)
But broadly speaking:

Shmitah and Ma'aser apply only to Israeli soil. If you pick up a bottle of kosher wine made in Israel and read the label carefully, there will usually be additional information near the kosher certification saying that these issues have also been addressed.
The requirement for kosher wine to be made by Jews starts from when it's "grape juice", i.e. pressing the grapes. Plain old table grapes bought at any grocery store (assuming they didn't grow in Israel) are kosher, no matter who handled them; and kosher wine producers don't have to worry about who picked or handled the grapes.
"Non-Israeli producers of kosher wine" -- if the wine is properly certified kosher, that means that it was handled by Jews from pressing until the bottle was sealed. There are kosher-certified wines available from France, Italy, Argentina, Spain, Australia, and the US, to name a few -- in all of those cases, there are Jews located there, making sure it's kosher. As long as you trust the certification, these are just as kosher as wine made in Israel (albeit they did not have the same tithing requirements). As many of these certifications are well-regarded, plenty of kosher wines are imported into Israel, with their French/Italian/Argentinian/etc. certifications then endorsed by Israeli certifiers. (It's similarly not uncommon, for example, if you're a US importer of Spanish wines, to talk to a US kosher certifier like the OU, have them check the Spanish kosher certification, and if they're satisfied, add the OU symbol, which the American consumer is used to seeing.)
Comment: You ignored her request for Orlah   and Kilayim.
Comment: @WAF I think the question is about how it's practically done today, at which point we follow all the laws -- Written, Oral, rabbinic.
Comment: You might want to differentiate between Written and Oral Torah requirements, since the question does not.
Comment: IIRC it's not really pressing the grapes but when you skim off the skins and seeds after pressing (it could be modern technology does that instantaneously with an open filter or something)
Answer: Shalom's answer is missing your request for laws of Orlah and Kilayim.
Specifically:
Orla: (Source: Kitzur Shulchan Aruch 173)

Most of the laws of Orla apply outside of Israel.
Relevant to vines: if a branch of a vine was buried and a new vine grew where it protrudes, there is no problem of Orla on the new vine. However, in Israel, the new vine becomes Orla if the buried branch is cut. Outside of Israel the new vine will not be Orla in this case.

Kilayim:(Source: Shulchan Aruch, Yoreh De'ah 296)

One may not plant Kilayim anywhere, nor may one ask a non-Jew to plant Kilayim.
To be considered Kilayim outside of Israel one has to plant 2 types of grains or vegetables together with the vine. In Israel the laws are stricter.
Outside of Isreal one need not check that the grapes are fom Kilayim; unless one knows for sure they are, they are permitted.
Comment: Thank you! You explained these complex ones in a much simpler way than I could. (That's why I'd left them out, I didn't want to drown the questioner.)


Is this going to be safe in the rain?

Question: Is this going to be safe in the rain?The contractor left it like this & the property manager doesn't care. It's directly under my bedroom window, so I'm a bit concerned.
Answer: No it is not safe. NEC requires all conductors to be installed in an appropriate enclosure or totally removed. I suppose I should give you NEC Article 110.3 for the reference that does not allow what your picture is showing.
You might want to quote this to your property manager and contractor.
Needless to say this is an unsafe situation and you might mention that they have a certain amount of liability if in fact some one is injured because of their lack of action. I am not sure if you are dealing with the installer or directly with the owner of the contracting firm that left it that way. Usually the owner is a lot more concerned than there employees. If that doesn't work I advise you to contact your AHJ have have them deal with the problem.
Stay safe and good luck.
Comment: Also, water will enter that conduit and end up... where?
Comment: That's what I thought!!

Is this going to be safe in the rain?


Is ubuntu installed with wubi have some differnces from general one

Question: When I install Ubuntu with wubi - is it the same if I simply install it? Like disk formatting, etc? Because I need ubuntu for mongodb and need to be sure it will be work as fast as normal one.
Answer: My understanding is that it is a bit slower for IO.
What performance differences are there when installing with Wubi?
...but to the best of my knowledge, wubi won't work with anything after 12.04.
http://ubuntuforums.org/showthread.php?t=2209033


The derivation of fractional equations

Question: Recently I saw some physical problems that can be modeled by equations with fractional derivatives, and I had some doubts: is it possible to write an action that results in an equation with fractional derivatives? For example, consider a hypothetical physical system with the principle of least action. Is there a "wave equation" with the time-derivative $3/2$? Does such a question make sense?
Comment: Here is the tome our group did a lot of work out of: [Metzler, R. (2000). The random walk's guide to anomalous diffusion: a fractional dynamics approach. Physics Reports, 339(1), 1–77. doi:10.1016/S0370-1573(00)00070-3](http://www.sciencedirect.com/science/article/pii/S0370157300000703). It is a great introduction to the subject. There should be an arxiv preprint available but I don't have the number handy.
Comment: Out of curiosity, what sort of physical problems work this way?
Comment: @Spencer I saw the first time in anomalous diffusion. You can see here, for example: http://www.pfi.uem.br/mfi/disserta_teses/teses_pdf/angel_akio_tateishi_2010.pdf (in portuguese). This is a investigation of a system governed by a non-Markovian Fokker-Planck equation that are related with the comb model.
Comment: Forces proportional to velocity, such as friction for example, can be described by putting fractional derivatives in the Lagrangian.
Answer: Fractional derivatives are nonlocal, but actions are usually assumed to be local.
Comment: Dear @space_cadet, no, what you write is not correct. QGR is right that whenever fractional derivatives appear, the action is nonlocal. It's enough for some terms to appear, whether they're leading or not, and the action has to be nonlocal. At the end of your answer, you admit that you don't really know why they're nonlocal. Well, it's because the you may write $\partial_t^k$ as $E^k$ in the Fourier transformed energy representation, and the transformation of the operator $E^k$ back to the $t$ basis is nonlocal.
Comment: @Boy, @genneth - thanks. @Lubos, all I was saying is that, AFAIK, having non-local terms is fairly common, eg. higher derivative theories of gravity. So being non-local should not be a obstacle for an action with fractional derivatives, as @QGR seems to suggest.
Comment: the locality or non-locality of a Lagrangian density depends on the highest order of derivatives in its various terms. Terms with upto second order derivative (eg. kinetic terms) are local. Terms with derivatives of order 3 and higher are non-local, with the degree of non-locality being measured by the order. So a non-local term in an action does not imply that the variational problem is ill-defined. Also why are fractional derivatives non-local? Even better, what is a fractional derivative? Thanks.
Comment: @space_cadet sloppy physicist thinking here, but I think it can be made precise: imagine taking a taylor series of the fractional derivative --- it would need to go to infinite order, and thus it would be highly non-local.
Comment: @space_cadet, a fraction derivative is a simple example of "pseudo-differential operator". It's an operator that can be easily defined for example with fourier transform (like Lubos Motl sayed). You can define operator that in Fourier Transform is equivalent to $\sin{k}$...Fraction derivative is simpler, in Fourier Transform is a multiplication for your transform variable $k$ with fractional exponent ;-)
Answer: When I've seen fractional derivatives I've assumed that one place where they would naturally arise is in physical situations where there's a fractional dependency on time.
For example, random walks typically result in movement proportional to $\sqrt{t}$. Googling for "fractional+derivative+random+walk" on arxiv.org finds some papers that explore this:
http://www.google.com/search?q=fractional+derivative+random+walk+site%3Aarxiv.org
So I'm wondering if there's a way of relating some of the diffusion versions of QM with fractional derivatives.
Comment: Exactly this is indeed done [here](https://en.wikipedia.org/wiki/Fractional_quantum_mechanics).

The derivation of fractional equations


custom post type and hidden url : what is the cleanest way to build CPT with custom page template?

Question: I recently built a website were I needed to let user edit the custom post type archive page with elementor. So I decided to use page templates instead of archive pages, that way,I can build my pages with code (custom loop) and elementor (widgets).
But after navigating in my website, I spotted strange behaviours. I'm sorry I have many questions, but I think they are all related to the same topic : the cleanest way to build CPT with page.
1-For my page template :
http://localost/mytheme/all-lessons

If I type for example, an url with the name of my CPT,
http://localhost/mytheme/lessons (the former CPT archive url)

I'm redirected to the first post of that CPT
http://localost/mytheme/all-lessons/lesson-1

I didn't made any redirection rules so I don't understand.
For all my custom post type I use the same code, with hierarchical=> false and has_archive =>false:
$args = array(
    'label'               => _x('Formation', 'text_domain'),
    'description'         => _x('Formations', 'text_domain'),
    'labels'              => $labels,
    'supports'            => array('title', 'editor', 'thumbnail', 'comments', 'revisions', 'custom-fields'),
    'hierarchical'        => false,
    'public'              => true,
    'show_ui'             => true,
    'show_in_menu'        => true,
    'menu_position'       => 5,
    'menu_icon'           => 'dashicons-admin-home',
    'show_in_admin_bar'   => true,
    'show_in_nav_menus'   => true,
    'can_export'          => true,
    'has_archive'         => false,
    'exclude_from_search' => false,
    'publicly_queryable'  => true,
    'query_var'           => true,
    'rewrite'             =>  array( 'slug' => 'toutes-nos-formations' ),
    'capability_type'     => 'post',
    'show_in_rest'          =>'true'
)

The strange thing is that for one of those CPTs, if I type the name of the archive page, I see a 404.

So Is there a way to completely disable CPT archive page system, so no one can access to those archive pages built by wordpress and I wouldn't have those strange behaviours ?
I have a custom post type for which I don't need single pages. They exist in backend because I 'm just displaying them in a grid, in a page template.

How can I do to entirely hide those single pages url ? because I dont want a user to see those page that are not styled at all.

As I'm using custom page, I loose the normal wordpress navigation system (current-menu-item ) So when I'm in a single CPT, the custom page in the menu doesn't highlight. Is there a simple solution for that ?
Answer: Ok maybe it's not a definitive answer, but for question 3 : this thread give a solution to highlight custom posts parent menu item, even if using a page template instead of archive page.


Can I verify that a "forgotten" subaddress belongs to my wallet?

Question: Consider the scenario where I delete my wallet then restore it from the seed phrase. Now all sub-addresses are lost. Then, I recover my sub-addresses by other means (e.g. logs). Can I verify that they actually belong to my wallet, and can I add them back to my wallet to use them again?
Answer: When restoring a wallet from seed phrase, you do not lose your subaddresses. This is because subaddresses are deterministically derived from you wallet keys. Therefore there is never a scenario whereby you would need to restore subaddresses "by other means" or " add them back to my wallet". By restoring a wallet, you have all the subaddresses too.
Getting technical, it is also possible to verify if you own a given subaddress. To do this you would need to create all the subaddresses that cover the range of possible indexes of the subaddress you wanted to check for a match. E.g. if you knew your wallet only had 2 accounts and up to 100 subaddresses, you would create the first 100 subaddresses for account 0 and account 1, then one of those will match the address you are checking.
Comment: An easy way of generating all those subaddresses [knaccc subaddress-js](https://github.com/knaccc/subaddress-js) module.
Comment: I made an offline [command-line utility](https://github.com/dan-da/subaddress-derive-xmr) for deriving addresses from mnemonic, seed, or private view key + public spend key.

You can generate any number of subaddresses you want.


Is there any way to bake texture from world space to UV?

Question: Hi I have a material with environment texture mapped with object space (like environment), and would like to bake it into the object UVs.
Now everything looks good in editor, I just make it look the same in Unity preferably with baked texture to improve the quality and so on. The problem is that I cannot find the way of bakeing it with the object's UVs
To be specific.
- I have an object with its own UVs
- Assigned a material with object space (environment texture mapping), which is
  nothing to do with object UVs
- I would like to bake the material texture as it looks but onto the object UVs
Is there any way to do this?
I don't mind bake the texture into vertex color and then bake it to texture whatever again. just want to avoid to doing arrange the rendered texture to fit into UVs as it is tedious and does not always fit well. Any ideas? Thx in advance!
Answer: Well I just figured it out. You can just bake it. super easy
What I did

Assign a material with HDRI environment texture based on object space mapping to your object.
Unwrap your object
go with bake and make sure bake the map you used in your shader i.e used diffuse node then bake diffuse, Emission then emit etc.

Baked image is perfectly projected on your UVs :)


Meaning of lines in Charging History details view in 4.2.2 Jelly Bean

Question: In 4.2.2 Jelly Bean when one goes to Settings -> Battery Use and tap the graph at the top can find the History details of the charging/discharging of the battery. There are some other historical data below the diagram:  - Mobile network signal was cleared  - Charging seems to be clear (green when charged, black when discharged)  - Screen on is also OK (blue when lit on, black otherwise)  - Wi-Fi may be similarly indicates the On/Off state of the function  - Awake is a mistery for me I can not see any correlation between the graph and the On/Off state of the phone  - Finally What does the GPS on line exactly indicate?
I have some GPS problem and try to report it. I need to know whether this line indicates the On/Off state of the GPS module or the positioned/lost position state. On my screen it is almost totally black however the module was switched on a day before. There are two or three momentary blue ticks. What do they indicate anyway?
Comment: posting a screen shot may help
Comment: I know. I have the screenshot but how to post it?
Answer: When the screen is off and no apps are running in the background (e.g. to check email), your device goes into a low-power state called sleep. In this mode, the CPU runs more slowly (or maybe the main CPU is turned off and a smaller, more efficient one takes over) to save power.
The Awake line in the battery chart shows when the device is not asleep: that is, it shows blue when the screen is on or when an app is running in the background. Depending on what kind of background apps you use, you might see brief ticks every 15 minutes or every hour, where the device woke up to perform some scheduled task. If there are long blue segments even when the screen is off, then some buggy app is keeping your device awake. You can investigate which with a tool such as Greenify or Wakelock Detector, and if an app is keeping the device awake, you should report this to the developer.
The GPS on line indicates when the GPS receiver is powered on. This happens whenever an app requests a precise location, and it'll show blue regardless of whether the GPS receiver has calculated a position or not. A brief tick means the GPS was turned on and then turned off as soon as it calculated a position. This is used by Google Play Services' geofencing functionality, by Google Location Sharing, Google Now, and other similar apps that don't track you all the time but want to sample your location occasionally.
Answer: Enabling GPS and using GPS are two different things, when you enable the use of GPS on the menu/toggle, you are just allowing the use of GPS, that dose no mean you acutely using it, when you see in the graph the little blue lines, that means that some application tried/used the GPS and get the exact location (e.g google now).
starting with Android 4.4 you can check which application used the GPS and when under the App permission menu.


Including GPL code into BSD project

Question: I have an open source project which I distribute under BSD license. I would like to include parts of iwlib.c, which is part of iwlib project, and which is released under GNU GPL 2.
To my understanding this is not possible unless I also change the license of my project to GPL 2, which seems quite silly. Is this correct? Can I overcome this limitation by, say, changing the code a bit (e.g. by changing variable names, removing comments etc)? Or by asking permission to the author?
Comment: @curiousdannii, why not write that as an answer.
Comment: To understand the philosophical underpinnings of the GPL, the [preamble of the license text itself](https://www.gnu.org/licenses/gpl-3.0.en.html#preamble) is a pretty good place to start. Perhaps the fairest way I can restate your above statement is that the GPL strives to disadvantage/exclude proprietary software at all costs, versus permissive licenses which strive to propagate code while being agnostic about proprietary use. Stallman (the first author of the GPL) is nothing if not philosophically opinionated, so he naturally created a very opinionated license.
Comment: It's not silly, it's the entire point of the GPL license. You don't get to take advantage of the GPL project unless you commit to giving your users the same rights as those you use the GPL code under. You can always ask the author for an exception, but why would they give you one? Changing the code a little would **not** be a legal way around the license.
Comment: I understand. Thanks for the replies. Then I must conclude that the main goal of GPL is literally to spread itself as a license as much as possible (as opposed to facilitate the flourishment of open source code).
Comment: The goal of the GPL is to ensure that open source projects remain open source. You should read [The History of the GPL](https://www.free-soft.org/gpl_history/) which outlines the events that led to the creation of the license. After reading that article, it should make 100% perfect sense why the license works the way it does.
Answer: You cannot overcome this limitation by changing the code a bit.  The GPL specifically protects against this, and, arguably, it is the central idea of the GPL.
Your only options are:

Change your license,
Ask the author if they will license their code to you under a different license, or
Find or create an alternative implementation with a BSD-compatible license.

Note that option #3 may also violate the GPL if you choose to write your own replacement and you don't do it cleanly from the ground-up (thus without looking at the original work as reference or ideas).
Comment: I hope you agree with the small addition with which I try to make even more clear what 'from groud-up' means. If not, feel free to revert
Comment: @planetmaker Thanks.

Including GPL code into BSD project