lidR: no slot of name "header" for this object of class "LAScatalog"

edit: This question does share an answer with , and the problem is the same: lastrees() does not work on LAScatalogs. However, I'm going to leave this question up, because I think the code and error message makes it easier to find.  I'm using lidR 2.0.3 (from the rocker/geospatial image). I would like to perform tree segmentation on an entire LAScatalog using the Li 2012 algorithm:   #### setup #####################################################################  # load packages library(here) library(lidR)  # load normalized point cloud catalog (just a pointer to the tiled point  # clouds) normalized_als =    readRDS(here::here('02-data',                    'lidar',                    'aerial',                    'normalized_als_catalog.rds'))    #### configure catalog ######################################################### # set catalog output path  lidR::opt_output_files(normalized_als) =    here::here('02-data',              'lidar',              'aerial',              '02-segmented',              '{ID}_segmented')  # don't use any points with Z below 0 when making the CHM lidR::opt_filter(normalized_als) =    paste0(lidR::opt_filter(normalized_als), ', drop_z_below 0')  # use n-2 cores to process lidR::opt_cores(normalized_als) = as.integer(parallel::detectCores()-2L)  # use a 20m buffer lidR::opt_chunk_buffer(normalized_als) = 20  # process by files - this may preserve the lasheader? lidR::opt_chunk_size(normalized_als) = 0  # run the algorithm, writing the segmented point cloud to disc segmented_als =    lidR::lastrees(normalized_als,                algorithm = li2012())    The last call to lastrees returns:  Error in algorithm(las):     no slot of name "header" for this object of class "LAScatalog"   I've confirmed that the individual las files DO have valid headers, but it seems that lidR::li2012() is assuming that "las" is a LAS object, not a LAScatalog. The call fails at line 219 of lidR/R/algorithm-its.R:   if (las@header@PHB$`Max Z` < hmin)   My question is: Is my code incorrect, or is this a bug in lidR::li2012()? I'm trying to follow the examples on , but I don't 100% understand how lidR maps LAS-based functions over LAScatalogs, and it's very possible that I am misusing the lastrees function. (Is there some catalog_apply() approach that I should be using?) The li2012() function seems to expect a LAS object specifically, not a LAScatalog (which doesn't have a comparable header slot). How can I pass an actual LAS object to li2012()? I would just iterate over the separate tiles, but would like to use the buffering functionality offered by LAScatalogs. Alternatively, was the data validation checking for li2012() written with a LAS object in mind, and causing it to break when given a LAScatalog or a LAScluster?  I would be happy to email a reproducible dataset, but I believe the issue should be reproducible with an arbitrary catalog: Either my code is written incorrectly, or li2012() can't currently be used on LAScatalogs.


Python Fundamental Counting Principle Possible Permutations

If given a list of strings such as arr = ["abc", "efgh", "ij"], I want to know all the combinations starting from the first word to the last using recursion. so the output will look like this: aei aej afi afj agi ... chj  all the codes I see are just using the permutation of one string. I've been thinking that the concept is something like the fundamental counting principle like the one in the picture but I can't really put it into code.


How to add a tag to my favourite tag list. I could search for a tag but don't know how to add that to my favourite tag list.


How to run Repeated Measures to find difference between gender (without change of condition)?

I would like to test for the difference of measures between genders. Repeated measures were carried out. What test would you suggest is best for this and what would be the degrees of freedom considering:      there is no change in conditions uneven group size (females=6 and males=4) missing repeated measures (8 levels) between 3 subjects**     The Data Explained There are 6 females and 4 males = 10 subjects in total 28 Repeated measures (events or levels) per person with no change in condition except time.  28 x 10 subjects = 280 repeated measures (rm)  At each level there should be:   19 ordinal independent variables (IV)   from which  7 continuous dependent variables (DV) are recorded  19 (IV) x 7 (DV) =  133 measures (one level per subject) 133 x 28 rm per subject = 3724 measures (all levels per subject) 3724 x 10 subjects  = 37240 total measures of data   Missing data (from the expected totals as described above)  8 levels of data between 3 subjects are missing:  2 events (rm) missing for 2 males  4 events (rm) missing for 1 female 280 rm - 8 rm  = 272 rm in total 8 missing rm x 133 measures per rm = 1064 total measures missing  37240 - 1064 = 36176 total measures of data


First time entry to Schengen area with student visa

I am currently living outside EU and I recently got a student visa from Germany (multi), but I would like to travel first to Sweden to visit a friend and then flight to Germany. Would that be a problem for extending my student visa, if I don't enter first Germany as a visa issuer?


Importing Drawings ( DXF,DWG ) in Altium

I'm having trouble importing DXF / DWG into Altium.  I followed File-->Import-->selected my dxf,dwg-->config-->Information show Done!!-->and nothing shows up on my mechanical layer.  I'm using Altium Version 15.1  Any tips or workarounds ?  THK


I have one equation* inside caption* in table as follows. \documentclass{article} \usepackage{amsmath,caption} \begin{document} \begin{table} \center \caption{This is a sentence.} \caption*{This is a sentence. This is a sentence. This is a sentence. This is a sentence. This is a sentence.} \begin{equation*} THISEQUATION=THISEQUATION. \end{equation*} \caption*{This is a sentence. This is a sentence. This is a sentence. This is a sentence. This is a sentence.} \begin{tabular}{cc}\hline 1&2\\ 3&4\\\hline \end{tabular} \end{table} \end{document}  I separated the caption* above because it cannot include equation* inside, so the resultant spacing of equation* is incorrect. Is it possible to let the caption* have the equation* inside?


Let $S^1 = \{(x, y) \in \Bbb R^2 : x^2 + y^2 = 1 \}.$ Let $D = \{(x, y) \in\Bbb R^2 : x^2 + y^2 \le 1 \}$ and $E = \{(x, y) \in\Bbb R^2 : 2x^2 + 3y^2 \le 1\}$ be also considered as subspaces of $\Bbb R^2.$ Which of the following statements are true?  a. If $f : D \to S^1$ is a continuous mapping, then there exists $x \in S^1$ such that $f(x) = x$.  b. If $f : S^1 \to S^1$ is a continuous mapping, then there exists $x \in S^1$ such that $f(x) = x$.  c. If $f : E \to E$ is a continuous mapping, then there exists $x \in E$ such that $f(x) = x$.


How to remove an icon from launchpad that does not appear in the Finder?

I have moved an installer into the launchpad (uTorrent-Installer). The problem is that I would like to remove it now but as it is an installer it doesn't appear in "Applications" in the Finder. I can't right-click the icon to remove it nor can I drag and drop it into the trash.  Can I delete apps from launchpad?


Post-Hoc pairwise comparison for slope (interaction term) in R?

I have been using scripts from package "Agricolae" but realised today that it compares only between the intercepts.   I expect that since i am testing for the interaction term using ANCOVA, the post-hoc test should do that as well instead of being a more general comparison. Or am i wrong? Are there are scripts/methods that does pairwise comparison for "slope" and "intercept"?? If Scheffe is not available, what is the next best option for unequal sample sizes?


$f$ is analytic function on open unit disk, and $|f(z)|\le 1-|z|\forall z\in D$, we need to show $f\equiv 0$, just a hint please.


Does grapple end the Invisibility spell for the grappler?

I was looking through the  when I noticed this:  When you make a Strength (Athletics) check to grapple or shove someone, are you making an attack roll? Again, the answer is no. That check is an ability check, so game effects tied to attack rolls don’t apply to it. Going back to an earlier question, the hex spell could be used to diminish a grappler’s effectiveness. And if the grappler’s target is under the effect of the Dodge action, that action doesn’t inhibit the grapple, since Dodge doesn’t affect ability checks.  I had always played that the 2nd-level invisibility spell would end on a grapple, since it counts as an attack, but this seemed to suggest otherwise. I researched this a bit and found  from December 2015, which seemed to suggest that it was indeed an attack roll:  Grappling/shoving an enemy does end the sanctuary spell on you, since you have made an attack.  My best guess is that you must take the Attack action to perform an ability check, as grappling in the PHB is called a “special melee attack” (PHB p. 195), although that doesn't make a huge amount of sense:  [...] you can use the Attack action to make a special melee attack, a grapple. [...]  Do these two answers by Crawford contradict each other? And should the invisibility spell end when a grapple is attempted? The description for the invisibility spell says:  A creature you touch becomes invisible until the spell ends. Anything the target is wearing or carrying is invisible as long as it is on the target's person. The spell ends for a target that attacks or casts a spell.


Proving that the limit doesn't exist for $x$ other than $0$

I have a problem/proof that I can't quite solve.  Let $$f(x)=\begin{cases}x^2\quad &x \in \mathbb{R} \setminus  \mathbb{Q}\\-x^2 \quad &x \in \mathbb{Q}.\\ \end{cases}$$ Prove that $$\lim_{x\to n} f(x)$$ doesn't exist for $n$ other than $0$.  Maybe I can use the regular epsilon-delta proof? I tried that but wasn't sure of what assumptions I could make with the absolute values. I would appreciate any help.


How do sites moderate self-answered questions?

Historically our beta site has discouraged self-answered questions. The site has been running for 6 years (3 questions/day, 98% answered, 3 ½ answers/question, and very few questions are closed). The topic of the site can be a bit "" (like Parenting, or amateur History), sometimes opinionated, and not entirely dry and technical like Stack Overflow. We have discouraged self-answered questions -- because, as one of the moderators says,  I'm strongly opposed to giving green light to quasi-questions posted with the sole intent to share an opinion, an unsolicited teaching, rambling, philosophical musings etc. [...] self-answering [might be] utilized to take advantage of the SE platform to push unsolicited info at the audience [...] I'm not convinced we should greenlight a random newbie getting on the proverbial soap box [...]. How are we to decide who is allowed to get on the box and who's not? I suppose the main issue here is community self-moderation or rather the lack thereof.  My experience of other SE sites has been that self-answering isn't an important feature -- that the large majority of topics, and of the most upvoted answers, are all people answering other people's questions. So IMO if the community votes it wants to avoid people using self-answered questions to preach on the topic of their own choice (i.e. by posting a rhetorical question and self-answering), then that's fair enough -- i.e. it's not a huge diversion from SE's core mission as a Q&A site. I'm aware that SE also usually  and hopes its sites may become like Wikis (which IMO is fair enough when the subject matter is like SO's). My fear is that self-answered questions may be:  Mostly summaries of or references to material already available online elsewhere A bit spammy (e.g. a summary of something on the OP's blog or YouTube channel) Someone might flood the site with unlimited self-answered topics It can be preachy -- users who disagree in their answers within one topic might use further self-answered questions to continue their disagreement into other topics People (or trolls) might post extremist, unorthodox, unwelcome, controversial views on topics of their own choosing.  Someone recently argued though that "experts" want to be able to post self-answered topics and won't frequent the site if they are not allowed to.  What's your experience (and on which site)?  Are self-answered topics a problem, a distinct category, difficult to control or to quality-control?  How do you (do you even) prevent people posting the kinds of low-quality or problematic content which I listed above)? What implements the prevention -- is it the community, the moderators, or some site-specific policies about what content is welcome?  Do self-answered questions seem a bit spammy sometimes?  says,  Always solve the asker's problem. A good answer should at minimum allow the person whose question you're answering to solve their problem. Not all questions can be answered this way, but if you don't think you can write up a complete solution then you're better off looking for a different question.  ... but a problem with self-answered questions is that there isn't even an asker -- the post is unsolicited, it's not cooperative like answering someone else's question.    Historically when someone posts a question in order to self-answer it, a moderator says, "That's not really conventional on this site, this is a Q&A site which is preferably for answering other people's questions". So we've had little experience with allowing self-answered questions -- and having to quality-control or moderate them. How does a site cope with the various kinds of problem listed above, without deprecating all self-answered questions categorically?


find: equal file size limit but different unit returns different result

I noticed that the these two commands to list files below 5 GiB produce different results:  find . -type f -size -5368709120c find . -type f -size -5G   Specifically the one that uses kilobyte unit (5368709120c) returns additional files that are larger than the maximum file size returned by the one that uses the GiB unit (5G).  From the find manual page I read the following:  -size n[cwbkMG]           File uses n units of space.  The following suffixes can be used:           `b'    for 512-byte blocks (this is the default if no suffix is used)           `c'    for bytes           `w'    for two-byte words           `k'    for Kilobytes (units of 1024 bytes)           `M'    for Megabytes (units of 1048576 bytes)           `G'    for Gigabytes (units of 1073741824 bytes)  The size does not count indirect blocks, but it does count blocks  in sparse files that are not actually allocated.  Bear in mind that the `%k' and `%b' format specifiers of -printf handle sparse files differently.   The  `b'  suffix always denotes 512-byte blocks and never 1 Kilobyte blocks,  which is different to the behaviour of -ls.   So, given that the unit of G is 1073741824, 5G should be 5368709120c. Is the issue due to how sparse or indirect blocks are counted?  Thanks in advance for the help.


If someone keeps entering and exiting my bedroom, and I want him to stop. Should I say:   don’t come in and out of my bedroom.   Or   don’t go in and out of my bedroom.   Is this just a case of directional difference between the verbs ‘come’ and ‘go’, or is it that only one of them fits as part of an idiomatic construction?  Also, apart from ‘in and out’, are there any other expressions/phrases that can express the same idea succinctly?


My parents are travelling from Jeddah to Cairo, arriving in Terminal 3.  Their connecting flight to Dubai doesn't leave until 30 hours after they arrive in Cairo. They are Pakistani passport holders.    Is there a possibility they can get hotel once they reach Cairo? They are ready to pay for one day hotel stay.  Can someone guide me on this?


I want to format a USB-Drive (/dev/sdc) and make multiple partitions each of a different type using fdisk. My fdisk uses sectors(not cylinders) to create a new partition. /dev/sdc1 <- NTFS  (10GiB) /dev/sdc2 <- Fat32 (04GiB)    Can someone please provide the step by step method to be used in a terminal ?


Geany compiler , c programming, Ubuntu 14.04, can't show program output

I wrote a simple program to print "hello world". The compiler shows a message "Compilation finished successfully". But the out put of the program, I can't see anywhere.    As using codeblocks a new terminal comes out with the program output. How can I see the program output using geany compiler.


Why does a generic varargs method called from another generic method return Object[]?

I encountered the following code in Joshua Bloch's Effective Java book but I can't understand why the pickTwo method returns Object[]? The method toArray returns Integer[]. So why does pickTwo return Object[]? I think it should return Integer[].  Joshua Bloch's book says that:     The type of this array is determined by the compile-time types of the arguments passed in to the method, and the compiler may not have enough information to make an accurate determination. Because this method returns its varargs parameter array, pickTwo will always return an array of type Object[].   public class JavaApplication52 {      public static void main(String[] args) {      System.out.println(toArray(1,2,3));      System.out.println(pickTwo(1,2,3));     }      static <T> T[] pickTwo(T a, T b, T c) {         switch (ThreadLocalRandom.current().nextInt(3)) {             case 0:                 return toArray(a, b);             case 1:                 return toArray(a, c);             case 2:                 return toArray(b, c);         }         throw new AssertionError(); // Can't get here     }      static <T> T[] toArray(T... args) {         return args;     } }   OUTPUT:  [Ljava.lang.Integer;@6d06d69c [Ljava.lang.Object;@70dea4e


Do you NEED BIND running next to Apache on a production env (apache is using virtualhosts)?

Good afternoon to you all. My question is perhaps a simple one. Say I have a webserver running (Linux + Apache) I have a few domains I'd like to point to this machine. all great and dandy BUT! Do I need a dns server like BIND to be running as well? or can I just host multiple websites using just apache and the virtual hosts? thanks guys!


I am adding following JVM parameters to connect the application via JMX. After connected the application via jconsole over JMX, is there a menu that shows me the running application PID?  -Dcom.sun.management.jmxremote  -Dcom.sun.management.jmxremote.port=5592  -Dcom.sun.management.jmxremote.authenticate=false   -Dcom.sun.management.jmxremote.ssl=false   Linux Redhat 6.2 java JDK 1.6


I have Ubuntu 16.04 and want to install C++ free compilator what shall I write in terminal?


How to read/write system RAM via physical address

My system is based on x86(64-bit) and it has 8GB RAM. I have set reserve 100MB of 8GB using memmap=100M@0x40000000.  For this way does it guarantee to reserve the 100M of RAM? Can I access the 100MB of RAM using address 0x40000000 in both user and kernel space? Of course I understand to need translate the physical to virtual address.


Adding more information to a PostGIS table via QGIS

I have a table within PostgreSQL/PostGIS that contains all point data. I need to add another large dataset to this existing table without overwriting the table. When I go into DB Manager within QGIS and try to import the new information I keep getting an error saying that the table I'm trying to write to already exists.   How can I add more information to this table without over writing the existing information already in the table? I wish to be able to do this with QGIS because it does all of the GEOM information for me.


Im trying to figure out how to reverse the string temp when I have the string read in binary numbers   istream& operator >>(istream& dat1d, binary& b1)     {                   string temp;       dat1d >> temp;     }


Hey, on using the parameters areEqualByThreeDecimalPlaces(-3.1756, -3.175), i am getting an error: More in the Details below

From the code below, after subtracting, in this case, for the variables numDiff1 and numDiff2, to chop off the whole number, the variable numDiff2 is reduced to  -0.174999999 which doesn't make sense as it is supposed to be -0.175. There seems to be a Bug in Java. Please let me know. Thank you. Is there any other alternative for this? public static boolean areEqualByThreeDecimalPlaces(double numOne, double numTwo){ //For the first parameter int num1 = (int) numOne; double numDiff1 = numOne - num1; // numDiff1 = -0.1756000000000002 numDiff1*=1000; int numFin1 = (int)numDiff1;  //Second parameter int num2 = (int) numTwo; double numDiff2 = numTwo - num2; numDiff2 = -0.17499999999999982 numDiff2*=1000; int numFin2 = (int) numDiff2;   if(numFin1 == numFin2){     return true; }else{     return false; //False }  }


I am currently in the process of learning how AES actually works and that works great as of now but when it comes to the Rijndael's key schedule I have a question. From what I have read, I have to make a expanded key that is 240 bytes in size to supply enough subkeys to the whole process of a AES encryption using a 256 bit key. Does this mean that I need to make the expanded key exactly 240 bytes or can I make it 256 bytes and discard the last 16 bytes? I ask this because from what I understand, each round of the key expansion gives me 32 bytes of round keys. In that case I have to do 8 rounds of key expansion to supply the encryption with enough subkeys since 7 rounds will only give me 224 bytes.


Building an archive of deleted questions

Back when the first discussion about deleted questions came up, I  building an official unofficial read-only archive for good deleted SE content.  I had a plan to build something like this:    Each link would point to a 1:1 scraped StackOverflow (or other SE network) deleted question (of course with a big fat disclaimer to the top, historical data, legal stuff, yada yada yada - and of course after asking Stack Exchange for permission, seeing as this would go far beyond what the CC license allows.)   I also registered a domain name that would (IMO) suit nicely, overflown.org.  However, when thinking about it, I realized doing this properly is a lot of work. You would have to:   build a scraper that can use a 10k+er's OpenID to fetch the deleted question (using the API or the data dump is for wusses. If we go through all this trouble, we want a historical document of what the site looked like "back then", right?) edit the page's DOM to remove dynamic elements, remove the "deleted" CSS classes, remove all the voting abilities from the buttons, and add the "this is historical data" disclaimer fetch - this is the biggest part and applies even if you use the API or data dump - all linked image resources (even those from imgur - even images used only in deleted questions could be purged one day), store them, and link them fetch all associated CSS style sheets and store them intelligently - preferably in a way that you don't fetch a copy of each file for each page (as normal page scrapers do), but also in a way that doesn't break if SE update their style sheets   long story short, I won't be in a position to build this any time in the foreseeable future - with old work, new work, and studying, I really have enough on my plate already.  Of course, if somebody else in the community feels like giving this a try, cool! But what I was really thinking is - maybe this is something Stack Exchange should build after all?   I know Jeff's  on these questions is used to be     @system I did think about a sweet place for them, in the bitbucket. – Jeff Atwood♦ Dec 29 '10 at 1:54   but come on. Think about it:     Future deletion discussions and changes in on-topicness policy would become way more relaxed because the popular and loved stuff has a place to go. A site for "overflown" questions could be curated by selected community members, who decide whether a contribution deserves to be archived or not.  A separate domain name (I'm happy to donate overflown.org for the purpose if desired) and the separate site design would create enough distance to the Stack Exchange network: it would be crystal clear that this read-only archive is for historical purposes only, and the existence of a question there does not mean you can ask something similar on one of the live sites. The pages would be 1:1 scrapes of what the site looked like at the time of the scraping, making it a general historical archive as well. These questions traditionally drive a lot of traffic. The possibility of continuing to show ads in the usual places would allow Stack Exchange to take advantage of that traffic without endangering content quality on the SE network. Hosting an archive like this is a job for a business, not us regular joes. A private project hosted by some community member can go down once they forget to pay a bill, or decide they want to password protect their private blog or photo album. The ideal place to host a site like this is at a company with professional admins that intends to stay online for a long time.    How about it?


"team of engineers IS standing by" or "team of engineers ARE standing by"?

Which is correct: "Our team of engineers is standing by" or "Our team of engineers are standing by"?


Finite ratios between pairs of infinities

I know that there are infinities of different magnitudes for countable things (e.g. via Cantor's diagonal argument), and that the ratios of the sizes of two such infinities may itself be infinite. However, how do ratios of infinities work for uncountable things? And can the ratio of two infinities of uncountable things be finite? Consider an infinitely large two-dimensional plane, consisting of a point $p$ and two unit vectors $v_1$ and $v_2$ rooted at $p$. Divide the infinite plane into two regions: $A$, the region of space spanned by the "wedge" centered at $p$, the "short way around" between $v_1$ and $v_2$, and $B$, the remainder of the plane (the "long way around"). The areas $|A|$ and $|B|$ are infinite, however it would seem that $|A| \over |B|$ is finite, since if a circle of any nonzero radius centered at $p$ is intersected with $A$ and $B$, the ratio of the areas of the two intersected regions would always be be the constant value $\theta \over {2\pi - \theta}$, where $\theta = cos^{-1}{{|v_1 . v_2|} \over {|v_1||v_2|}}$. (Actually maybe I am mistaken, and points on a plane are countable, by extension of Cantor's argument to two dimensions...)


Prove that for any integers $x, y$ and $z$ and any integer $k$that if $x \equiv_k y$ and $y \equiv_k z$ then $x \equiv_k z$

I was wondering if my proof is right and if there are better methods of solving this proof?   My proof:   Assume  $x \equiv_k y$ and  $y \equiv_k z$ is true. This means that :   \begin{align}x &= y + kq,&&\text{where }\;q ∈\Bbb Z,\tag{1} \\ y &= z + ka,&& \text{where } a ∈ \Bbb Z. \tag{2} \end{align}  By substitution of $(2)$ into $(1)$ we get:   \begin{align} x &= z + ka + kq \\   &= z + k(a + q),&&\qquad \text{where }\: a ∈\Bbb Z \text{ and } q ∈ \Bbb Z \end{align}  This proves $x \equiv_k z$ is true. $\blacksquare$


i try to instal mavros in ros kinetic ubuntu 16.04, but i cannot install    $ ./install_geographiclib_datasets.sh bash: ./install_geographiclib_datasets.sh: Permission denied   I tried:   sudo chmod -x ./install_geographiclib_datasets.sh   but it doesn't fix that permission. what should i do to fix this??


If Republic credits are no good, what is used for or what is money called on Tatooine? Water would be an obvious currency but some form of 'cash' is seen being used.


Where does the period go when using parentheses?

Where should the period go when using parentheses? For example:     In sentence one, I use this example (which has a parenthesis at the end.)   Should the period be inside, or outside of the parentheses? What about if the entire sentence is a parenthetical (as below)?     (Where does the terminal punctuation go here?)   Is there a hard and fast rule?


Proving $\binom{2n}{n} \geq \frac{2^{2n}}{n+1}$

How can I prove this? $$\binom{2n}{n} \geq \frac{2^{2n}}{n+1}$$ I tried using AM-GM but it didn't help.


Many people say that in C++ endl is much slower than \n when printing a string. They explain that endl flushes the buffer and \n doesn't. In the book C Primer Plus it's said that      "Sending the output from the buffer to the screen or file is called   flushing the buffer."   and that      "The standard C rules for when output is sent from the buffer to the   screen are clear: It is sent when the buffer gets full, when a newline   character is encountered, or when there is impending input."   So isn't technically printing an newline character flushing the buffer and still why is endl slower ?


Transfer from NRE account to a local Indian account is it taxable

This may sound like a repeated question yet I would like to be sure on the answer.  I am currently working in US. I do occasional transfer from my US account to my Indian NRE account (ICICI Bank) which I believe is not taxable as per the clause. Also I do have a Home Loan account (with IDBI Bank) in India. Now been at onsite I can afford transferring some additional funds so that I can close my Home Loan as early as feasible.   I usually transfer my monthly EMI's along with some additional cash from my ICICI NRE account to IDBI account. Now the question is, Is the amount transfer to my IDBI account taxable as per the Indian policies?


Proof that $\vert\int_a^bf(t)dt\vert\le\int_a^b\vert f(t)\vert dt $ for complex integration

The following proof is given in my notes: Write the complex integral $\int_a^bf(t)dt = Re^{i\theta}$ where $$ R=\int_a^bf(t)dt. \quad(1) $$ On the other hand, $$ R=\int_a^be^{-i\theta}f(t)dt.\quad(2) $$ Write $e^{-i\theta}f(t)=U(t)+iV(t)$ where $U(t)$ and $V(t) $ are real-valued functions. Then because R is real,  $$ R=\int_z^bU(t)dt\quad(3) $$  But now, $$ U(t)= Re\ e^{-i\theta}f(t) \le e^{-i\theta}f(t)=\vert f(t)\vert\quad(4) $$ Therefore, from the properties of real integrals, $$ \int_a^bU(t)dt\le\int\vert f(t)\vert dt $$ which proves the desired result.  I have trouble figuring out how each of the numbered equations actually hold. After writing the integral as $\int_a^bf(t)dt = Re^{i\theta}$ How can we say that (1) and (2) hold. (3) sort of makes sense as R has to be real.


What is $\Delta t$ in the time-energy uncertainty principle?

In non-relativistic QM, the $\Delta E$ in the time-energy uncertainty principle is the limiting standard deviation of the set of energy measurements of $n$ identically prepared systems as $n$ goes to infinity. What does the $\Delta t$ mean, since $t$ is not even an observable?


Show that arithmetic mean of numbers obtained is $\frac{n+1}{r+1}$

Consider the smallest number in each of the $n \choose r$ subsets (of size r) of $S = \{1, 2, \ldots, n\}$. Show that the arithmetic mean of the numbers so obtained is $\frac{n+1}{r+1}$   I've tried counting the number of times every integer appears, but it seems too complicated (for me). Is there any way this can be done without induction?


How come for loops in C# are so slow when concatenating strings?

I wrote a program that runs a simple for loop in both C++ and C#, yet the same thing takes dramatically longer in C#, why is that? Did I fail to account for something in my test?   C# (13.95s)  static double timeStamp() {     return (double)(DateTime.UtcNow.Subtract(new DateTime(1970, 1, 1))).TotalSeconds; }  static void Main(string[] args) {     double timeStart = timeStamp();      string f = "";     for(int i=0; i<100000; i++) {         f += "Sample";     }      double timeEnd = timeStamp();     double timeDelta = timeEnd - timeStart;     Console.WriteLine(timeDelta.ToString());     Console.Read(); }   C++ (0.20s)  long int timeStampMS() {     milliseconds ms = duration_cast<milliseconds> (system_clock::now().time_since_epoch());     return ms.count(); }  int main() {     long int timeBegin = timeStampMS();      string test = "";      for (int i = 0; i < 100000; i++) {         test += "Sample";     }       long int timeEnd = timeStampMS();     long double delta = timeEnd - timeBegin;      cout << to_string(delta) << endl;     cin.get(); }


Fine the value of $P(n+1)$ given values of $P$ from 1 to $n$

$P(x)$ is a polynomial of degree $n$ that satisfies $P(k)=\frac{k}{k+1}$ for $k=0,1,2,3,...,n$. Find $P(n+1)$.  What have I tried: I have literally no idea how to do questions of this kind. Also, in general what is the method solving such questions where they say a polynomial behaves a certain way with a range of numbers and expect you to extrapolate the next value?  Thank you!


My Mac is getting really slow, what should I do?

I bought a Mac (13", early 2011) almost 5 years ago. When I first got it, it was running under OS X 10.7 and it was pretty fast. I've being upgrading it ever since and it's now running under Mac OS X 10.11.  I guess it didn't totally survive the upgrades because, today, there's a lot of bugs, freezes, lags, "spinning beach ball" appearing,... for example, when I write something on a normal program/editor, the cursor freezes for a few seconds, then catches up to what I'm writting.  As you can guess, that's really annoying! I've been thinkning about upgrading the hardware but I don't know what to do: should I change the RAM to 8 GB - 1 333 MHz (currently my computer has 4 GB - 1 333 MHz)? Or should I upgrade to an SSD (which is pretty expensive and difficult to install)?  Thank you very much.


Using 'a' or 'an' different in speaking and writing

There is an acronym- RPD. In a ppt, made by my teacher for the students, there is a sentence-  When the posterior abutment opposes the edentulous space or a RPD.  However as I speak this sentence I automatically use an RPD due to the sound of 'aar' for R. So is it correct that a same sentence is written and spoken but one with 'a' and other with 'an'? Or something is wrong, me or the ppt?


I have seen many schematics using 22 ohm resistor in series with digital signal lines.  I was wondering is this always a MUST or there are there some special scenarios where we don't need them since they lower the signal's bandwidth.   For instance, are they needed on 48MHz signal line which is cca. 2cm long?  Is this somehow connected to STM32 output speed capabilities (low, high, ultra high speed, etc.)?


Stopping overnight at London Heathrow - do I need an arrival visa and what kind?

In May I'm stopping at Heathrow Airport for 24 hours, on the way to New York from New Delhi. I'm an Indian passport holder and I have a 10 year US visitor visa.  Can I leave the airport and which visa would I need for that?


Word for people who have the same affliction

Suppose two people meet and learn that they both suffer from similar or analogous afflictions – e.g., they both:   Spilled their meal on the floor. Have been walking through the same desert, both looking for something lost Are suffering from diseases with similar characteristics   Is there a single word that could allude to this relationship or the fact that they share a similar or analogous affliction or misfortune?  This is a more general case of   Neither that nor "partners in misfortune" works because the people in question are not (necessarily) partners or fellows.  I don't want to assert more than that "they're in the same boat" (to incorporate the first answer).  E.g., none of the following attempts work: "We are affliction twins."  "She is my relationship sympathizer."  "You are my co-sufferer."


I am experiencing a weird unknown behavior in excel. The sheet I want to export to a csv file consists of 4 columns with data like this:  site.aspx|de|lblChanges.Text|some text that will be used somewhere   Now what happens is, if the last column containg the text has doublequotes in it, Excel adds another double quote to it for every double quote already in it.  Example:  site.aspx|de|lblChanges.Text|some text that will used somewhere here   Gets transformed into  site.aspx|de|lblChanges.Text|"some text that will used somewhere here"   Notice the extra doublequotes at the beginning and the end, which clearly should not be there. this data gets inserted in a database and used as text resources for globalization. If I render a literal control with those extra double quotes the functionality breaks.  How can I supress this behavior in Excel?


I have this cat then sed operation:  cat ${location_x}/file_1 > ${location_y}/file2 sed -i "s/0/1/g" /${location_y}/file2   Can this be done in a single line?  I might miss such a way , but that explanation seems to me to deal with the opposite of that, and I fail too unite the above cat and sed into one operation without double ampersand (&&) or semicolon (;) and getting closer to assume it's not possible, but it's important for me to ask here because I might be wrong.  Not all readers are English speakers are familiar with the terms "ampersand" or "semicolon" so I elaborated on these.


Wasn't Rey cold on Starkiller base? Shouldn't this have impacted her somehow?

Rey grew up in an environment that was desert like. For her entire life prior to the movie, she was used to a warm environment (at least daytime).    It's clearly snowing, but she is wearing the same outfit she routinely wore on a planet that was described by Star Wars wiki with a climate of "." We don't know how cold the base was, but it's snowing, so clearly colder.  While I might not be a Jedi-in-training, when I go to an environment that is significantly colder it affects me physically. And I live in a climate which has seasons - not having grown in a desert for 20 years.  Shouldn't Rey have been somehow physically affected by this? Or at least.. been really cold?  Inspired by


I'm having problems trying to overload the post increment operator in C#. Using integers we get the following results.  int n;  n = 10; Console.WriteLine(n); // 10 Console.WriteLine(n++); // 10 Console.WriteLine(n); // 11  n = 10; Console.WriteLine(n); // 10 Console.WriteLine(++n); // 11 Console.WriteLine(n); // 11   But, when I try it using classes, it looks like the objects are exchanged.  class Account {     public int Balance { get; set; }     public string Name { get; set; }      public Account(string name, int balance)     {         Balance = balance;         Name = name;     }      public override string ToString()     {         return Name + " " + Balance.ToString();     }      public static Account operator ++(Account a)     {         Account b = new Account("operator ++", a.Balance);         a.Balance += 1;         return b;     }      public static void Main()     {         Account a = new Account("original", 10);          Console.WriteLine(a); // "original 10"          Account b = a++;          Console.WriteLine(b); // "original 11", expected "operator ++ 10"         Console.WriteLine(a); // "operator ++ 10", expected "original 11"     } }   Debugging the application, the overloaded operator method, returns the new object with the old value (10) and the object that has been passed by reference, has the new value (11), but finally the objects are exchanged. Why is this happening?


I have a Figure with 3 images inside (a) (b) and (c) when I want to write the description of each image in the figure this description is not so well aligned I mean I would like to see something like this:   Figure 2  (a) Image corresponding to...            (b) Image corresponding to...            (c) Image corresponding to...    Everything aligned in the center just like in the other figures.  But instead of that I am having.     Figure 2 (a) Image corresponding to... (b) Image corresponding   to...(c) Image corresponding to...   I do not know if I was clear enough but I would appreciate any answer  Thanks a lot.


Let R and S be binary relations on a set A. Solve for each case: If R and S are i) reflexive, ii) symmetric, iii) transitive, what would R∪S be?

I had a similar question just now and it peaked my interest on binary relations. Solving i) "Assuming R and S are reflexive so: Let x ∈ A.  Then (x, x) ∈ R and (x, x) ∈ S (reflexive property of R and S). R ∪ S would then be reflexive as well, since (x,x) ∈ R ∪ S." Does that make any sense? As in, is this correct to assume? How would one go about proving it for R ∩ S? If R ∩ S = (x,x) it'd also be reflexive, wouldn't it? What about the symmetry and transitivity of R ∩ S?


What is the difference between \big[ (or equivalently \big() and \bigl[? Is it always necessary to mention l (left) and r (right)?


How to get time difference in minutes in PHP

How to calculate minute difference between two date-times in PHP?


Can we define an ordered pair as $(a,b)=\{a,\{b\}\}$? It seems like a good definition to me. It fits, $$(a_1,b_1)=(a_2,b_2)\iff (a_1=a_2 )\wedge(b_1=b_2)  $$


Find the maximum value of $x^3 + y^3 + z^3$ where $x, y, z \in [0, 2]$ and $x + y + z = 3$.

Given that $x, y, z \in [0, 2]$ and $x + y + z = 3$. Calculate the maximum value of $$\large x^3 + y^3 + z^3$$   I'm done. Should you have different solutions, you could post them down below. Having a solution there already, I want to see unfamiliar thoughts.


Which path is a relative pathname in a shell script relative to?

If a bash script contains a relative path ( to specify a file, a directory, ...), which path is the relative path  relative to,    the pathname to the parent directory of the bash script, or the current directory where we run the bash script?   If I may ask, do similar questions in a Python script, in a Java program, in a C program, in a C++ program, .... have the same answer?  Thanks.  I don't see any similarity with the linked question. I am asking about what a relative path in a program is relative to.


I forgot the passcode for my iPad restrictions. How can I disable them?

I added restrictions to my iPad and I forgot the passcode for them, now what? Is there a way to remove it without resetting the device?


Using custom fonts without administrator rights?

I know you can put custom fonts in say C:\Windows\Fonts and applications will be able to find and use them. However this is only possible when you have administrator access to the machine, which is rarely the case in shared environments.  Is there a general way to use custom fonts from some other location suitable for non-admin users? If not, is there any manner specific for Adobe Fireworks (CS3) and Office 2007?  I'm interested mainly in XP and Vista, but a solution that works for other Windows versions would be great.


If $a_n$ monotonic, $a_n>0$, and $\sum\sqrt {a_na_{n+1}}$ converges, prove $\sum a_n$ converges.

need help solving this problem:  Given $a_n$ monotonic, $a_n>0$.  prove that if $\sum\sqrt {a_na_{n+1}}$ converges then $\sum a_n$ converges.


Is there anyway to expand my MacBook Air's hard disk?

I have a 2011 MacBook Air(11-inch), I am using OS X 10.9, but I only have 64GB Flash Storage, and I  want to expand the storage of MacBook Air's hard disk. I asked geniuses at Apple and they told me the answer is no. So, is this possible?


Why doesn't a particle in uniform circular motion fall into the centre?

If a object is in uniform circular motion, I know there is a acceleration directed radially inward. If that's the case, shouldn't there be a velocity radially inwards at some time. If that's true. Why does it not fall in that direction? know that i am a idiot. Please help me see how it works.


I Am only 12 years old and I'm constantly wondering and trying understand how gravity really works. On YouTube everyone always talks about objects wrapping space time  around themselves and uses the analogy of a trampoline. I still don't understand gravity because if space were like a trampoline, then earth would be spiralling in towards the sun along with all the other planets, right? So could someone explain to me how gravity really works without the trampoline analogy.


My right arrow key doesn't work anymore. Maybe it's a hardware failure but is there an easy workaround maybe a software key remapping? I have tried to open my pc to no avail.


Let $f(z)=\sum_{n=0}^{\infty}a_nz^n$ with radius of convergence equals to $R$. Show that for every $r<R$:  $$\frac{1}{2\pi}\int_{0}^{2\pi}|f(re^{it})|^2dt=\sum_{n=0}^{\infty}|a_n|^2r^{2n}$$  I tried this:  $$\int_{0}^{2\pi}|f(re^{it})|^2dt=\int_{0}^{2\pi}f(re^{it})\overline{f(re^{it})}dt=\int_{0}^{2\pi}\sum_{n=0}^{\infty}a_nr^ne^{int}\sum_{n=0}^{\infty}\overline{a_n}r^ne^{-int}dt= \int_{0}^{2\pi}{\sum_{n=0}^{\infty}\sum_{k=0}^{n}}a_k\overline{a_{n-k}}r^ne^{int}$$  But this is about it. Any ideas?  Thanks!


MS SQL Server: Do multiple queries in a batch ever execute in parallel and if so what happens when the second query is dependent on the first?

If I have a batch of two different SELECT statements, is it possible for them to be executed in parallel (if the SQL Optimizer deems it to be the most efficient execution method)?  If the first SELECT statement is selecting into a temp table and the second SELECT statement is then inserting into that same temp table, does that prevent it from being possible for the two statements to be ran in parallel?  (I'm guessing the answers are yes and yes :).


my MiKTeX can't find the package fancyhdr

I have tried installing it but it just says not found like this  LaTeX Error: File `fancyhdr.sty' not found.  Type X to quit or <RETURN> to proceed, or enter new name. (Default extension: sty)  Enter file name: kpsewhich fancyhdr.sty  ! LaTeX Error: Missing \begin{document}.  See the LaTeX manual or LaTeX Companion for explanation. Type  H <return>  for immediate help.  ...                                                l.12   Then I tried to manually install it through MikTeX package manager(admin) and it just give me this message  MiKTeX Problem Report Message: The MiKTeX web service has rejected your request. Possible reason: too many requests arriving from your IP address. Data: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN""http://www.w3.org/TR/html4/strict.dtd"> <TITLE>Service Unavailable</TITLE> <META HTTP-EQUIV="Content-Type" Content="text/html; charset=us-ascii">
Service Unavailable

HTTP Error 503. The service is unavailable.
   Source: Libraries\MiKTeX\PackageManager\PackageManager.cpp Line: 132 MiKTeX: 2.9 OS: Microsoft Windows 8 Home Premium Edition, 64-bit (build 9200) Invokers: explorer SystemAdmin: yes PowerUser: no Root0: C:\Users\Benjamin\AppData\Roaming\MiKTeX\2.9 Root1: C:\Users\Benjamin\AppData\Local\MiKTeX\2.9 Root2: C:\ProgramData\MiKTeX\2.9 Root3: C:\Program Files (x86)\MiKTeX 2.9 UserInstall: C:\Users\Benjamin\AppData\Roaming\MiKTeX\2.9 UserConfig: C:\Users\Benjamin\AppData\Roaming\MiKTeX\2.9 UserData: C:\Users\Benjamin\AppData\Local\MiKTeX\2.9 CommonInstall: C:\Program Files (x86)\MiKTeX 2.9 CommonConfig: C:\ProgramData\MiKTeX\2.9 CommonData: C:\ProgramData\MiKTeX\2.9   so hope u know how to do it


I recently just lost some time figuring out a bug in my code which was caused by a typo: if (a=b)  instead of: if (a==b)  I was wondering if there is any particular case you would want to assign a value to a variable in a if statement, or if not, why doesn't the compiler throw a warning or an error?


Recovery mode shell prompt with read-only file system?

I'm trying to install a video driver on my Ubuntu 16.04 system, and the instructions caution me to set runlevel to prevent the X server from starting. Using what was posted in  I've had problems doing that, so as a workaround I decided to boot to recovery mode and use the "root shell prompt" option.  This worked fine until I tried to run the run file and fouond that I forgot to set the executable bit.  I entered a cdmod command. It came back with the message "readonly file system."  So I have to return to the X server to start a terminal window and set the executable bit.  Except that once I do, I won't be able to use the run file anyway because it has to write files to do its job.  So recovery mode gives me root access but makes the file system read only? What? Is this some kind of stupid joke?


Can lightning be used to solve NP-complete problems?

I'm a MS/BS computer science guy who is wondering about why lightning can't (or can?) be used to solve NP complete problems efficiently, but I don't understand the physics behind lightning, so I'm posting here.  What seems peculiar to me about lightning is that it seems to follow the "easiest" path to a given destination, as opposed to just the shortest path. This seems analogous (identical?) to the weights in the traveling salesman problem.  Since the lightning process ionizes the air and seems to pick the easiest route quickly, I have 2 questions:  1) Does lightning use a method similar to Dijkstra's approach (such that a "good enough" path is found in polynomial time, but not necessarily the "best of all options")? Is it basically an NP "solver"?  If the answer to the above question is "no" and it is indeed the best pick:  2) Could the selection process of lightning be used in a computer algorithm to solve a traveling salesman-type problem in polynomial time, and  3) If not, could an arbitrary series of weighted nodes be physically set up somewhere and have electricity passed through it and have the results fed back into some kind of computer mechanism for every time a user wants to know a shortest path?  If you could use this approach to solve NP-hard problems quickly, you would have your name on the news and maybe in the history books. So why hasn't anyone used lightning to solve this problem?  UPDATE: Another aspect I find interesting: when lightning strikes it ionizes the air to find the shortest path. If the world were totally flat (and the clouds were also) this would ionize all the air equally. Which leads me to believe the route "picked" by the lightning incorporates all points, which seems to be a requisite for finding the best of all solutions.


Cannot mount NTFS volume; fixntfs doesn't resolve the problem

I am trying to mount a USB harddrive with NTFS.  Ubuntu displays this eror message:   sudo fixntfs didn't resolve the problem.   linuxcomprrrr@rr-a-computer:/home/rrrr# sudo ntfsfix /dev/sdd1 Mounting volume... Failed to load runlist for $MFT/$DATA. highest_vcn = 0x1ba0a, last_vcn - 1 = 0x1a60a Failed to load $MFT: Input/output error FAILED Attempting to correct errors... Failed to load runlist for $MFT/$DATA. highest_vcn = 0x1ba0a, last_vcn - 1 = 0x1a60a Failed to load $MFT: Input/output error FAILED Failed to startup volume: Input/output error Checking for self-located MFT segment... OK Failed to load runlist for $MFT/$DATA. highest_vcn = 0x1ba0a, last_vcn - 1 = 0x1a60a Failed to load $MFT: Input/output error Volume is corrupt. You should run chkdsk. linuxcomprrrr@rr-a-computer:/home/rrrr#    How can I fix the volume from Ubuntu?


How to align two images side by side if one label has more lines

I have two same sized images and want them side by side with a caption under them.  My code looks like this:   \begin{figure}[H] \centering \begin{minipage}{.5\textwidth}   \centering     \includegraphics[width=\textwidth]{3}     \caption{label1}   \label{fig:test1} \end{minipage}% \begin{minipage}{.5\textwidth}   \centering     \includegraphics[width=\textwidth]{4}     \caption{label2}   \label{fig:test2} \end{minipage} \end{figure}   which works fine until one of the labels has 2 lines, than it looks like this:    and I woud like to prevent it to look something like this:    How can it be done?  Thanks


I am new to Stack Overflow. After commenting repeatedly on an answer from somebody, suddenly a warning (automatic, I guess) popped up: "Please avoid extended discussions in comments. Would you like to automatically move this discussion to chat?"  I get the idea behind this move. Only problem: As a newbie, I can't use chat rooms. Wouldn't it be better to show this warning only, if you actually can use chat rooms?   On a side note: These automatic warning messages might scare away new users. My first posting got a warning like "Postings with these headlines are often down voted and deleted". It nearly made me leave the site. Maybe a less restrictive warning, if you are not a repeat offender, would increase the attractiveness to new members.


How can you figure out which program/process is creating a file?

Suppose there's a file that keeps appearing in my home directory automatically even after I delete it. Knowing nothing more about it, is there a way to figure how what keeps putting that file there? Is there a way to track down the program/process that creates it?


Particularly, does proc always list the VmRSS value in kB? I can't find a solid answer on the , although it appears that it sticks to one unit.


Limit to infinity and infinite logarithms?

When trying to evaluate$$\ln(\ln(\ln(\ln(\cdots\ln(x)\cdots))))$$I noticed that the answer was bound to be complex for any $x$.  Plugging in a very, very large real number in for $x$ will eventually become complex, and the $\log$ of a complex number is always complex or imaginary.  But what happens when we try to evaluate $$\lim_{x\to\infty}\ln(\ln(\ln(\ln(\cdots\ln(x)\cdots))))$$  We see that $$\lim_{x\to\infty}\ln(x)=\infty$$Meaning that if we try to do this repeatedly, we should still get infinite as our final result.  But we also see that for arbitrarily large $x$ where $x$ is real and finite, the result is a complex answer.  Which creates a sort of contradiction.  What does it evaluate to?!?!


I heard someone make an assertion that 'We cannot really prove that there is reality.'.  'Reality' here would mean the universe and everything in it. You could look at an apple and think its an apple but it could really be something else, and we cannot really prove its "appleness".  My initial answer was the mere fact that having a notion for reality is proof enough that there is such a thing.  My question is: Is that a sufficient answer? Is there a proof that reality exists? Or is the question a valid one to begin with?


I'm stuck. Help (I don't know what happened)

I was modelling for an hour, then this happened. I saved, closed it and came back but the same thing was still there.... help....


Should we reword the closure text for duplicate questions?

On the Gaming.SE Meta, I asked  regarding how the duplicate close reason text (for when a question is voted as a duplicate by the community) should be changed.  From my post, here is what the current close text states:    My proposal was to have it changed to something that refers to editing the question to be more clear and allow for it to be reopened.  My suggestion was:     This question has been asked before and already has an answer. If those answers do not fully address your question, or if your question is actually different than the duplicate, [please edit your question] to be more clear and allow for it to be reopened.   Where the part within the [ ] would be a link to the edit page for the question.  It is to my understanding that usually we don't recommend people to ask a new question but to rather edit the current one and allow for it to be reopened. In fact, most of the time when someone asks a new question, it's flagged as a duplicate of the duplicate (at least over on Arqade).  The reason I ask this here, is because I flagged my post for a moderator to view it and have the changed implemented/submitted to SE, but they said it's an Exchange wide close reason, and that we couldn't change it.   So, should we reword the closure text for duplicate questions or is asking a new question the proper protocol?


Can we remove the ( ) bracket from Theorem 1.2.1 ( [7])

Can we remove the ( ) bracket from the environment like Theorem 1.2.1 ( [7]).


Dual monitor DELL P2415Q MacBook Pro 13" early 2015

Does anyone know if I can connect two 4k monitors running at 60Hz to my MBP 13" early 2015, 3.1 GHz Intel Core i7, 16 GB 1867 MHz DDR3, Intel Iris Graphics 6100 1536 MB). Specifically, I am interested in the DELL P2415Q.  My understanding is that I can connect 2 monitors with res 3840 x 2160 via the two thunderbolt ports, but only one can run at 60Hz, the other must run at 30Hz.  Any help is appreciated!  Thanks!


Intraclass correlation coefficient vs. F-test (one-way ANOVA)?

I'm a little confused regarding the intraclass correlation coefficient and one-way ANOVA.  As I understand it, both tell you how similar observations within a group are, relative to observations in other groups.  Could someone explain this a little better, and perhaps explain the situation(s) in which each method is more advantageous?


Let $p, q > 1$ such that $\frac{1}{p} + \frac{1}{q} = 1$. Then $$|\sum\limits_{i = 1}^n x_i y_i| \leq ||x||_p ||x||_q, \;\; \forall x, y \in \mathbb{R}^n.$$ I have to prove it considering $$u = \frac{x}{||x||_p} \;\; \text{and} \;\; v = \frac{y}{||y||_q}$$ and using $\bf{Young's}$ inequality. Can someone, please, give me a hint?


Why is my camera limited to a shutter speed of 1/250th when the flash is up?

Sometimes in bright backlight and with large aperture (f2.8) I want flash at high shutter speeds.  But when I pop the flash up on D7000 it caps the shutter speed to 1/250th, which overexposes the shots and makes everything look like a nuclear bomb just went off.  What's the logic behind the limiting of the shutter speed when using flash? Is there anything I can do to get flash  + faster shutter speeds?


Ubuntu 15.04 doesn't start with nvidia driver

I upgraded from Ubuntu 14.10 to 15.04 and since then when I use the proprietary Nvidia driver Ubuntu doesn't boot.   It shows "Starting 219" on my secondary screen and on my primary screen it shows something like "Starting Display Manager" and at this point it gets stuck.


How to create an image with complex gradient?

I need to create an image like this, but I do not know what software or technique to use. I tried to use the Mesh Tool in Illustrator, but the result is odd, also I tried to blur an image in Photoshop, but I need to use some particular colors.


When modifiers applied, sculpting doesn't work correctly

I have made a mesh with mirror- and subsurface modifiers but when I apply them and switch to sculpt mode, it says "the object has non-uniform scale, sculpting may be unpredictable".     When I try to sculpt, the result is with any sculpting tool this:    Sculpting works with any object/mesh but this and if I try to recreate it with the same methods as this one, it does the same thing.


Retrieve ResultSet from MySQL using ArrayList in Query

I'm not sure how to write it in a way the query will take all the values stored in the excludeRooms and use it in the query then add the results to the tableRoomsData vector  Code:      List<String> excludeRooms = new ArrayList<String>();     Vector<String> tableRoomsData = new Vector<String>();      m.dbConnect();       PreparedStatement stmt = m.getCon().prepareStatement("SELECT * FROM room_view                 WHERE room_num != ?");     //get all data where room_num is not equal to the room numbers stored in excludeRooms       result = stmt.executeQuery();      while (result.next()) {     d.add(result.getString("room_num");     d.add(result.getString("room_type");     }   PS.  I'm a total newbie in Java and is trying to create a program alongside learning on my own. This is also my first time to post a question here so I hope you could bear with me on my formatting.         Thank y'all in advance!


What's the word for prefacing an attack with "I'm sorry for having to do this, but"?

There is a single obscure word whose very definition is when one says "I'm sorry for saying this, but" or "I hate to tell you this, but", and then proceeds to do the very opposite and attacks or lambasts the person they're talking to. For the life of me I can't find it and I've searched high and low. Can someone please help me? Many thanks and cheers!


How to create remote desktop access application using java?

I have two computer in different network.I want to control one system from another.Both system have windows 7 operating system.Do any one have any idea how to do it?? I don't want to use team viewer or any other application.


How do I save progress on local Flash games?

Before Adobe Flash completely shut down I downloaded a bunch of .swf files along with the Flash Player application so I could play them once it all went offline. But after playing a game, I'm not sure how long it is, but the progress I made would eventually disappear no matter what the game. I'm not sure if it's different since I'm not doing it in a browser, but how do I save the progress for these games permanently?


nullPointerException error driving me crazy

So I'm doing a project on Arrays using 2 classes and a tester class but I keep getting a nullPointerException error. I know what the error means essentially and I believe the problem lies in my Tank class provided below and its constructor to be more specific. The Tank class uses my class Fish and is supposed to create an array of fishes, and the tester then creates a new Tank object.   public class Fish{    private int weight;   private String name;    public Fish(int w, String n){     weight = w;     name = n;   }    public void feed(){     weight = weight + 5;   }    public int getWeight(){     return weight;   }    public void setWeight(int w){     weight = w;   }    public void setName(String n){     name = n;   }    public String getName(){     return name;   }    public void starve(){     weight = weight -5;   }    public String toString(){     return name +"'s weight is: " + getWeight();   } }   Here is the Tank class:  import java.util.ArrayList; public class Tank{    private boolean isFish = true;   private int size;   private int index = 0;   private Fish[] fishArray;   private ArrayList<Fish> fishTank = new ArrayList<Fish>();    public Tank(int i){    fishArray = new Fish[i];   }    public Tank(){     fishArray = new Fish[10];   }    public void feedFish(int i){     fishArray[i].feed();   }    public void addFish(Fish f){     fishArray[index] = f;     size++;   }    public void starveFish(int i){     fishArray[i].starve();   }    public String getNameFor(int i){     return (fishArray[i].getName());   }    public int getWeightFor(int i){     return (fishArray[i].getWeight());   }    public int getTotalWeight(){     int w = 0;     for(int i =0; i< fishArray.length; i++){       w = fishArray[i].getWeight() + w;     }     return w;   }    public Fish getLargest(){     int heaviest = Integer.MIN_VALUE;     for(int i = 0; i < fishArray.length; i++){       if (fishArray[i].getWeight() > heaviest)         heaviest = fishArray[i].getWeight();       index = i;     }     return fishArray[index];   }    public Fish getSmallest(){     int small = Integer.MAX_VALUE;     for(int i = 0; i < fishArray.length; i++){       if (fishArray[i].getWeight() < small)         small = fishArray[i].getWeight();       index=i;     }     return fishArray[index];   }    public boolean doesExist(Fish f){     for(int i = 0; i < fishArray.length; i++){       if(fishArray[i].getWeight() == f.getWeight() && fishArray[i].getName().equalsIgnoreCase(f.getName()))         isFish = true;       else isFish = false;     }     return isFish;   }    public ArrayList<Fish> transfer(){     for(int i = 0; i < fishArray.length; i ++){       fishTank.add(fishArray[i]);}     return fishTank;   } }   as you can see, I am trying to build an overloaded constructor inside the tank class that creates an Array of fish objects but I'm having some trouble getting it to work. I believe that this is where my error is coming from in my tester class:  public class TankTest{   public static void main(String[] args) {      Tank tank = new Tank();     tank.addFish(new Fish(10, "Doris"));     tank.addFish(new Fish(12, "Marlin"));     tank.addFish(new Fish(7, "nemo"));     tank.addFish(new Fish(15, "bubbles"));     tank.addFish(new Fish(18, "gill"));     tank.addFish(new Fish(5, "peach"));      tank.feedFish(3);     tank.starveFish(2);     tank.starveFish(4);     tank.feedFish(5);     tank.starveFish(1);     tank.feedFish(0);     tank.feedFish(2);     tank.starveFish(5);     tank.starveFish(1);     tank.feedFish(3);     tank.feedFish(1);     tank.feedFish(5);     tank.starveFish(0);        System.out.println("The total weight is : " + tank.getTotalWeight());     System.out.println("The largest Fish is : " + tank.getLargest().getName() );     System.out.println("The smallest Fish is : " + tank.getSmallest().getName() );      tank.transfer();    } }    Any help would be appreciated


"Simple Touch UI" not available in ubuntu-sdk

I've installed the ubuntu-sdk according to :  sudo add-apt-repository ppa:ubuntu-sdk-team/ppa && sudo apt-get update && sudo apt-get install ubuntu-sdk   But when following the  I find some discrepancies between the tutorial and my setup.  It says:  Select the Projects > Ubuntu > Simple Touch UI template and click   But all I get is    So I choose to go HTML5 and two steps further I'm at the Kit selection page which says  No valid kits found.   Any ideas where to go from here?  The system is Ubuntu 13.04


Ubuntu 16.04 locks up when screen turns off

I have just set up a desktop box with Ubuntu 16.04.  It is working fine, except it locks up when the display shuts off per system settings under brightness & lock.  I researched this a little and found  that suggests editing /etc/default/grub to set   GRUB_CMDLINE_LINUX_DEFAULT="quiet splash usbcore.autosuspend=-1"   and  that says the parameter you have to change on recent Ubuntu releases is "autosuspend_delay_ms".  I have tried both using the procedure in the first link, and the autosuspend value remains 2 even after changing the grub conf file and restarting it. I can't find out what the 2 value that is set is supposed to indicate.    The second link suggests some other things to try but it's not clear that these apply to Ubuntu. I don't want to mess around until I know I'm doing the right thing because I don't want to hose my nice clean install.  Other things I've read says this applies to laptops that shut down USB to save power, but this is a desktop so maybe usbcore.autosuspend is not even what is causing the lock up.     Can anyone recommend a way to proceed?


Inline code in comment causes overflow of code container outside of answer/question comment section

Using Chrome Version 90.0.4430.93 (official Build) (64-bit) on Linux, this happens :


Schengen visa for two stop overs in Germany? I do have a valid F1 visa for US

I am travelling to USA from India and I have two layovers in Germany (Frankfurt and Dusseldorf). Do I need a transit visa or a Schengen visa?   Will I be exempted from Schengen visa, since I hold a valid f1 visa?


How to leverage a user defined variable in a command to create a condition in an if

I have a script which takes input for two variables from users. Then, I try to use those variables in a command which is in turn being fed into a condition in an if. However, the user input value is not replacing my variables and as a result, my command is not working -  # Get acl and dc values echo "Type the ACL name:" read acl echo "Type the DATACENTER name" read dc # see if sw-list-cisco file exists in ~/$acl directory" if [ ` ls -1 ~/$acl/sw-list-cisco > /dev/null | wc -l ` -gt 0 ]; then     echo "Going to do something" else      echo "no match !!!!!!!!!!!!!" fi   The if [ ` ls -1 ~/"$acl"/sw-list-cisco > /dev/null | wc -l ` -gt 0 ]; condition doesn't seem to be replacing $acl with the user input value. I have verified manually that sw-list-cisco exists in the ~/$acl directory.  What am I missing?


How to deselect part of a selected range in Excel 2013+

I'm using Excel 2013 and I'm having trouble deselecting part of a range that has been selected.  For example, if I select column C then Shift+click column E all the columns from C to E are selected.  Now say I want to deselect column D, leaving columns C and E selected.  I used to be able to Ctrl+click on the column and it would appear white, showing that it was deselected (the remaining selected columns would stay grey).  Now, however, when I Ctrl+click on column D instead of appearing white it gets darker.  The more I Ctrl+click the darker it gets.  According to the following Microsoft Support article this is a change in the design of Excel from 2013 onwards:    Their work-around is just to deselect everything and only select the columns I want.  Is there no way now that I can deselect part of a selected range?


I am a Jamaican who lives and works for the government as an educator in Japan. I would like to travel to the UK for several reasons.   Even though I have a 10 year U.S. visa, as a black woman, I do not feel safe staying in the U.S. at this time. I have a friend I haven't seen for years who lives in London I need to buy a wedding dress and some clothing items, unfortunately Japan doesn't cater to curvy women   I am nervous about the application process because it is rumored that Jamaicans have a hard time. So here are my questions   Should the amount shown in my bank account reflect the cost of my stay in London, as well as the airfare and hotel costs? I'd like to pass through the UK to go to Jamaica for 5 days, and then an additional  4 days in London, should my bank account reflect the amount for my trip to Jamaica as well?


Why doesn't gcc produce a warning for this

I mistakenly forgot to include the name of a function when writing a statement. Only in debugging did I find this out as everything compiled fine. I am surprised that gcc did not produce a warning for a C program like this.  int x =0, a=1, b=2, c=3, d=4, e=5, f=6, g=7;      printf("\n%d %d %d %d %d %d %d %d\n",x,a,b,c,d,e,f,g);  x = (a,g=b+c,d,e,f);      printf("\n%d %d %d %d %d %d %d %d\n",x,a,b,c,d,e,f,g);  x = a,g=b+c,d,e,f;      printf("\n%d %d %d %d %d %d %d %d\n",x,a,b,c,d,e,f,g);   The code should have read functionName(a,g=b+c,d,e,f) but was missing the function name.  The syntax  x = (a,g=b+c,d,e,f) results in x = f The syntax  x = a,g=b+c,d,e,f   results in x = a  In both cases g was properly calculated as b+c.  Wouldn't a warning of the first version x = (...) been in order? What valid stand alone expression would appear with (...) in this way. The byproduct is the inclusion or exclusion of the parens also results in two different values for x. Setting x=f due to the parens looks like a fall out from the way the machine code was generated as opposed to being syntactically driven.   Seems that a warning should have been flagged that perhaps this grouped expression was really the parameters of a missing function call. Better to catch a warning like this than having to discover the issue during debugging.


Ho can I make a figure like the following with tikz package?


I have an 29" LaPierre Hardtail. What is the difference between 29" wheels and smaller ones?  I'd like to know this not only for single trails but also on the road and / or downhill trails.


Are there some magic lines to be placed in the preamble that would, like in CSS,  specify how each generic section or subsection in the whole document should be formatted?


Set custom added PATH vars to work in each Terminal session

I ran these 2 commands simply in the terminal:  export PATH="$PATH:/home/milkncookiez/Developer/android-studio/bin" export PATH="$PATH:/home/milkncookiez/Developer/PhpStorm/bin"   in the 2 bin folders I have the files studio.sh and phpstorm.sh. In that same terminal session when I simply wrote the name of the files - the programs were ran.  When I opened another terminal - did not work. I added these both lines in the ~/.profile file, opened a new terminal session but it still does not work. How do I set the 2 variable changes to be permanent for all terminal sessions?


First off, I am fairly new to Linux so any help will need to be fairly step-by-step.  I have an HP Stream 14 on which I just installed Ubuntu 16.04. No dual boot; it will be the only OS I have. It has no ethernet port so I cannot connect to the internet to run a sudo apt-get update or anything like that. It has the Broadcom BCM43142.  I have tried installing dkms and bcmwl-kernel-source as well as Software & Updates -> Additional Drivers but it says "No additional drivers available."  Output of sudo lshw -class network:     *-network                       description: Network controller        product: BCM43142 802.11b/g/n        vendor: Broadcom Corporation        physical id: 0        bus info: pci@0000:01:00.0        version: 01        width: 64 bits        clock: 33MHz        capabilities: pm msi pciexpress bus_master cap_list        configuration: driver=bcma-pci-bridge latency=0        resources: irq:35 memory:fe900000-fe907fff    Output of lspci:   00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1566 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Mullins [Radeon R3E Graphics] (rev 02) 00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Kabini HDMI/DP Audio 00:02.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 156b 00:02.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 00:08.0 Encryption controller: Advanced Micro Devices, Inc. [AMD] Device 1537 00:10.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB XHCI Controller (rev 11) 00:11.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] (rev 40) 00:12.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 39) 00:13.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 39) 00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 42) 00:14.2 Audio device: Advanced Micro Devices, Inc. [AMD] FCH Azalia Controller (rev 02) 00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 11) 00:14.7 SD Host controller: Advanced Micro Devices, Inc. [AMD] FCH SD Flash Controller (rev 01) 00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1580 00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1581 00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1582 00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1583 00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1584 00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1585 01:00.0 Network controller: Broadcom Corporation BCM43142 802.11b/g/n (rev 01)    Output of rfkill list all:   0: hci0: Bluetooth     Soft blocked: no     Hard blocked: no


The difference between: I’ve been rescued and I was rescued?

Can you tell me what is the difference between:  I have been rescued  and  I was rescued  I know the first one is in the present perfect tense (so it’s an unstated time in the past and has an importance in the present, is it right?) and the second one, is in the simple past tense but I can’t seem to understand the subtle differences.


Show there is an unique complex number $z \in D(0,1)$ such that $ze^{\lambda-z}=1$

I need to show there is an unique complex number $z \in D(0,1)$ such that $ze^{\lambda-z}=1$ where $\lambda>1$. I know already, from the intermediate value theorem, there is an $z \in ]0,1[$ that satisfies this. How do I prove this z is unique in $D(0,1) \subset \mathbb{C} $? Thank you!


the chief of the National Se-curity Guard (NSG), which fought  the intruders, told me   that  he was certain there were six terrorists in-side. He said two terrorists hiding  in the airmen’s billet,which was blown up, could have  been caught alive had leitunent colonel  Niranjan not died while handling the bodies  of the four terrorists killed  earlier.   In this sentence how the speaker using "have been caught alive had".   can u express the meaning of sentence


I find myself quite often in a situation where I edit a question or an answer and I would like to also leave a comment explaining reasons behind my edit so that a user can also understand and maybe don't do the same mistake again. Also 9 of 10 situations are similar, if not the same, like those I already went through in the past.   removing a tag from a title removing an IDE tag from tags where it's not relevant to the question formatting code posted as a plain text ...   I would like to have there a picker with standard and custom comments so that I edit a post, select a comment if needed and it would post the comment below the post on save.  I know that many people do these tasks every day and do not leave an explaining comment, I don't do it myself when accessing SO via phone, for example. I believe that this feature would help to spread some basic rules among new users as they tend to not read them directly.


How do I GRANT for all tables across all schemas

I want to  GRANT SELECT     ON ALL TABLES     TO foo;   But postgres tells me I have a syntax error at "TO". It expects a GRANT like:  GRANT SELECT     ON ALL TABLES     IN SCHEMA public     TO foo;   We have a handful of tables that have been sharded such that public, shard123, and shard124 all have a table my_table, and public.my_table is the parent of both shard123.my_table and shard124.my_table. I've GRANTed SELECT to foo for public schema, but foo doesn't have permission for any of the shard schemas.  I've also done:  ALTER DEFAULT PRIVILEGES     FOR ROLE dba     GRANT SELECT     ON TABLES     TO foo;   ...which should automatically grant for any new tables and schemas made from now on.  There are 1000 < n < 10000 shards/schemas, so GRANTing separately for each shard/schema is impractical.  How can I GRANT to a role for all existing tables across all existing schemas (all shards)?  Or even better, can I GRANT for all schemas LIKE 'shard%'?


Convergence of product of convergent series

Given $a_n, b_n$ such that $\exists N   \forall n>N  a_n, b_n \geq 0$ I want to show that if $\sum_{n=0}^{\infty}a_n$ and $\sum_{n=0}^{\infty}b_n$ converge then $\sum_{n=0}^{\infty}a_n b_n$ also converges.  I tried to show it in the following way, if $\sum_{n=0}^{\infty}b_n$ converges, then $\lim_{n\rightarrow\infty}b_n=0$, so there exists $n_0$ such that $b_{n_0}\geq b_n$ for all $n\gt n_0$, therefore $a_n b_{n_0}\geq a_n b_n$, so that $\sum_{n=0}^{\infty}a_n b_n\leq \sum_{n=0}^{n_0}a_n b_n+b_{n_0}\sum_{n=n_0+1}^\infty a_n$, and as my series is bounded by sum of finitely many terms and tail of convergent series multiplied by a constant it's also convergent. Is my proof correct, or are there any flaws in my reasoning?


Dimension & non - locality problem in string theory

I have some questions with string theory:   Why is it that there is exactly 4 large spacetime dimensions while the rest remain small? It is a nonlocal QFT. How could that fit in GR?


Today I read in Wall Street Hournal next title:     Wells Fargo to Pay States About $575 Million to Settle Customer Harm   Claims   Why do they use “to” after Wells Fargo? Was there omitted something?


Hi i have total 3 partition in windows7   (C) Windows OS (D) erase all content for ubuntu (E) For files    I want to install Ubuntu on D drive. How to install Ubuntu here?   And after installing Ubuntu here is the left partition become 2 only in Windows.   Please help me.


Sorry for the vague title--I don't want the title to be a spoiler.  I've seen the movie three times, and the last two times I looked specifically for clues to this question, but found none.  The final scene in  shows       Cobb's top spinning, as he goes off to be reunited with his children.  The top continues to spin, then the movie ends, without telling us if the top topples--and therefore revealing whether he's in the "real world" or still in a dream. Do we know if he was in a dream at the end of the movie?   I'm assuming the answer is that we simply cannot know.  But did I miss anything?  Were there clues that I missed?


What's the logic behind the fake/real computer chip?

So in Now You See Me 2, after the Horsemen steal the computer chip that Walter Mabry wanted, Daniel goes to the market to try to hand over the chip to someone from the Eye, but it turns out he was tricked by Walter. He's cornered and ordered to give it up, but Dylan cuts in and saves him.  Dylan gets beaten up and half-drowned, but the Horsemen save him. Right then, Jack says the chip is a fake. Then there's a whole scene where they're discussing what to do and how they could suddenly have a fake chip, and how they lost the real one.   But later, on the plane, Daniel is coerced into giving Walter the chip, which turns out to be real again. So was it real the whole time? Or was it switched with a fake, and right up till the end, the Horsemen were still pretending it was real? And if so, where did the real one go?


Is it common practice to a write recommendation letter for oneself and let the professor sign it?

I am an undergraduate student at a Chinese university. Recently I asked for recommendation letters from two professors at my university, one Chinese and the other American, in order to apply for a summer program at a US institution. I have taken courses from both of these professors and performed quite well.   Upon hearing my request, the Chinese professor asked me to first write the recommendation letter for myself and then send it to him so that he can modify and sign it. The foreign professor, on the other hand, wrote the whole letter all by himself. I was later told by my classmates that it is the "common practice" for many professors in China to ask the student to write the recommendation letter for himself and then sign it.  Now my questions are: (1) Is the same thing a "common practice" in western universities? (2) Is it ethical for professors to transfer the load of writing the recommendation letters to students themselves? (3) I feel extremely uneasy when trying to write something that is supposed to praise myself. Is there any method for overcoming this uneasiness?  I would sincerely appreciate any help in answering my questions. Thanks!


Completing the square but in different situation

Solve the equation $$x^2+4\left(\frac{x}{x-2}\right)^2=45$$   My attempt,  I decided to use completing the square method, so I change it to $$x^2+\left(\frac{2x}{x-2}\right)^2=45$$  But I never encounter this before. Normally, for example $x^2+4x=5$, we can change it to $x^2+4x+(\frac{4}{2})^2=45+(\frac{4}{2})^2$. But in this question is different. Could someone give me some hints for it? Thanks in advance.


In The Lord of The Rings: The Fellowship of The Ring, the Fellowship passes through the Mines of Moria, which is an evil infested wasteland. It is unknown to Gimli how this happened as he still thought it would be maintained by Dwarves. I've also heard somewhere else in LOTR of someone being referred to as a refuge of Moria. So my question is; how did Moria go from a Dwarven mine to an evil-filled hole? If it mentions this in the book I may have missed it.


What is the max length of browser URL for Window.Open

I have this GWT code that opens a new browser window to show a text file.       Window.open("data:text/plain;base64," + Base64.byteArrayToBase64(textBytes), "_blank", "");   My questions are:   How long is the maximum URL part that a browser can handle? And what is the maximum bytes that this code will be able to handle properly?


Can we prove Conservation of Angular Momentum without assuming internal forces are central?

The only proof I've seen of Conservation of Angular Momentum assumes that the internal forces of the system act along the line joining particles i and j (i.e. - all internal forces are central.) Can we prove Conservation of Angular Momentum without this assumption?  If not, how can we apply conservation of angular momentum to systems that involve collisions, such as the following:  A uniform circular turntable is at rest in the $xy$ plane and is mounted on a frictionless axle, which lies along the vertical $ z$ axis. I throw a lump of putty (mass $m$) with speed $v$ toward the edge of the turntable. When the putty hits the turntable, it sticks to the edge, and the two rotate together with angular velocity $\omega.$ Find $\omega.$


Problem while saving a pdf file from a browser using Ubuntu 18.04

This newly appeared in Ubuntu 18.04 and was not seen in previous versions.  First when we save a pdf from a browser (firefox and chromium), a dialogue box pops up asking us to enter the file name and/or choose a location.   Secondly In previous versions of Ubuntu, this dialogue box could be dragged around to any location on the screen, in 18.04 this does not happen and what is worse the popup dialogue box freezes the entire browser so that one can not scroll down the background page.   This becomes especially irritating as while saving a file I generally give a file name similar to the title of the article, but with this new feature, the dialogue box blocks the title and forces me to do extra work.   Is there a workaround? Can this be changed in upcoming updates?


//intent.putExtra(EXTRA_MESSAGE, "abc"); intent.getStringExtra(Home.EXTRA_MESSAGE) == "abc" // false intent.getStringExtra(Home.EXTRA_MESSAGE) == getString(R.string.abc) //false (with R.string.abc=="abc")  String abc = "abc"; intent.getStringExtra(Home.EXTRA_MESSAGE) == abc //false   Why everything is false? If I print the values with a toast they're apparently identical.  Thanks.


How to install Deepin desktop in ubuntu 19.04

I tried this command but it doesn't work   sudo add-apt-repository ppa:leaeasy/dde   it says  Reading package lists... Done                                                   E: The repository 'http://ppa.launchpad.net/leaeasy/dde/ubuntu disco Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.   I also tried changing "disco" to "bionic" in  /etc/apt/sources.list.d/leaeasy-ubuntu-dde-disco.list  but when I try to install it with this   sudo apt-get update sudo apt-get install dde   it says   Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  dde : Depends: dde-desktop but it is not going to be installed        Depends: deepin-wm but it is not going to be installed E: Unable to correct problems, you have held broken packages.   I also tried   sudo aptitude install dde   it installs but I am not able to start dde with startdde because the binary is not in the path.  I also don't see any Deepin entry in login menu.   and I tried all answers in  and  but no luck.   does anyone know how can I install dde?


How to update/upgrade any phone to Android 4.4

Variations on this question appear to be a common unanswered question; often they have a comment or two that I don't understand. I'm hoping someone can answer with some general background information, the concepts.  E.g. I see reference to "rooting". Do I need to root a phone before I can upgrade it? I've had previous Android phones that got auto-updated (either by the carrier or manufacturer: I just find a message that says: "a new update has been downloaded, click here to install"), and I didn't need to root them.  E.g. Can any smartphone be upgraded to Android 4.4? If not why not? And why might a manufacturer not want users to update their phones? Are some manufacturers more open to having phones updated, and some not? Does anyone keep a list of "upgrade-hostile" manufacturers?  E.g. does the phone being sim-locked (to a specific carrier) matter?  I'm not going to say what my phone is because that will distract from the more general answers I'm after.


I am a complete new-be when it comes to Linux and even more so when it concerns Ubuntu.  I want to configure the IPv4 settings to have automatic assigning of IP address but manual assigning for DNS. How do I do it?  Please teach me how to do it step by step.  Please take a look at the image to get an idea of what I am asking.  Thank you in advance.  Windows DNS settings example:


Quick logic question about $P\leftrightarrow Q$, terminology

I know that if we have $P\rightarrow Q$, $P$ can be called the antecedent and $Q$ the consequent or conclusion. If we have $P \leftrightarrow Q$, are there names for what we would call $P$ and $Q$ here?  I am writing a proof where I am proving $P \leftrightarrow Q$ and I already showed $P\rightarrow Q$ and I am trying to show $Q\rightarrow P$ but the statement of $Q$ is long and I was wondering if there is a word for $Q$ that I could use.


Is it true that only the positions of the first and last letter in a word matter, the rest can be scrambled?

I read this sometime ago,     Aoccdrnig to a rscheearch at   Cmabridge uinervtisy, it deosn't mttaer   in waht oredr the ltteers in a wrod   are, the olny iprmoetnt tihng is taht   frist and lsat ltteer is at the rghit   pclae. The rset can be a toatl mses   and you can sitll raed it wouthit   porbelm. Tihs is bcuseae we do not   raed ervey lteter by it slef but the   wrod as a wlohe.   I'm guessing that the Cambridge research probably doesn't exist, but is it true that we can normally understand a sentence whose letters are scrambled in this way?


Is there anything that says The Doctor must be a man? I would love to see The Doctor come back as a ginger girl, and my friend tells me he thinks The Doctor cannot change gender. Is this true? If so where does it say that?


How to compile a document that you can search the pdf for latex math formulas?

Is it possible to compile a latex-document in such a way, that you can search for math formulas in the resulting pdf file by searching for the corresponding latex code? For example open the resulting document in evince and search for \int_3^5 f and you will find all occurrences the typeset math formula where the source contained \int_3^5 f.  The normal pdf search function should be unaffected.   I think in principle this should be possible since you could parse the math information at compile time and add them appropriately to the pdf ocr layer. However is there already a package or option which implements this?


SSH connection problem with "Host key verification failed..." error

I can connect to another Ubuntu machine in my LAN via SSH. On both of then PC's I installed   but from another Ubuntu computer I can not connect to my PC via SSH and I got this error:     Host key verification failed...


I would like to advertise my  on StackExchange. After spending 10 minutes creating a 220x250 image, I was told that new users can't link images. I have been around a while on SO, so I feel this is a little over-protective. I need at least 10 points. Can someone upvote me, please?


How to return two values from one method

I am trying to create a method that returns the fastest marathon time from an array (int times[]) of times, and also gives the corresponding name of the individual who ran that time.  The names of individuals are in a separate array (String names[]). The order of times[] corresponds to the order of names[], meaning the name of the person in names[0] has a running time of times[0], and so on.    I have been able to return the lowest integer from times[].  I am having trouble figuring out how to link the lowest time to the name of the runner, and print both values (e.g., names[0] + ": " + times[0]).  Any help would be appreciated.  *I would like to see how this is done without the use of a pair class.  Here is my code thus far.  public class Marathon {  static int i = 0;  public static Integer firstPlace(int[] value) {     int time = value[0];     while (i < value.length) {         if (value[i] > time) {             time = value[i];             i++;         } else {             i++;             continue;         }     }     return time; }  public static void main (String[] arguments) {     String[] names = {             "Elena", "Thomas", "Hamilton", "Suzie", "Phil", "Matt", "Alex",             "Emma", "John", "James", "Jane", "Emily", "Daniel", "Neda",             "Aaron", "Kate"     };     int[] times = {             341, 273, 278, 329, 445, 402, 388, 275, 243, 334, 412, 393, 299,             343, 317, 265     };      System.out.println(Marathon.firstPlace(times)); } }


Virtnetwork Cannot Start Virtualizor KVM

I have a problem with my virtnetwork. I have set the correct network interface on master setting Virtualizor but it said     /etc/sysconfig/: error fetching interface information: Device not   found Error: No ip address found.   when I try to run  service virtnetwork start   Does anyone can help me? Here is my network interface "ifcfg-ens9"  NAME="ens9" DEVICE="ens9" ONBOOT=yes NETBOOT=yes UUID="805c90c6-a8d2-49f1-8707-44696466a9fa" IPV6INIT=yes BOOTPROTO=none TYPE=Ethernet DNS1=127.0.0.1 DEFROUTE=yes IPV4_FAILURE_FATAL=no IPV6_AUTOCONF=yes IPV6_DEFROUTE=yes IPV6_FAILURE_FATAL=no IPADDR=xxx.xxx.187.234 PREFIX=29 GATEWAY=xxx.xxx.187.233 IPV6_PEERDNS=yes IPV6_PEERROUTES=yes   Looking forward for the solution. I don't know whats wrong the setting above.


I'm mostly a .Net person at the moment, but I've been playing with Java some lately-- exploring what's out there.  Now I'm looking for the Java equivalent for WPF.  I know I could find an OpenGL library or two out there, but that's not really as rich or simple as the WPF system.


If we take point (2,1) as the center point and ... then point (3, 3) is transformed into point ___

So I was practicing for an exam, and through my studying I found this problem. I really don't know how to solve it although the answer must not be too complicated since the question that came with this one were fairly simple. I first thought that maybe I could use vectors to solve this problem. I tried using this equation:    I noticed that this wouldn't help since I would then have the following equation :. I would have two variables to solve for using only one equation so I couldnt solve it.   I also thought of using geometry thus making a triangle with two sides equal to sqrt(5) thus it would have an angle of 45 degrees and two of 67.5 degress. I could then proceed to use sine rule but this wouldn't work out for me since I am supposed to do the problem with calculator.   Can someone help me?


How to set one header for each page using multicols

I want to use multicols in my document and also having a small box on each page (upper left) to be drawn automatically. I already tried \AtBeginPage hooks but the box didn't print at proper position... I've defined \header for what I want as a box:    MWE:  \documentclass[10pt,landscape,a4paper]{article} \usepackage[utf8]{inputenc} \usepackage[ngerman]{babel} \usepackage[utopia,sfscaled]{mathdesign} %\usepackage[lf,minionint]{MinionPro} %\renewcommand{\sfdefault}{phv} %\usepackage[lf]{MyriadPro} \usepackage{multicol} \usepackage[top=0mm,bottom=0mm,left=0mm,right=0mm]{geometry} %\usepackage{hyperref} \usepackage{lipsum} \usepackage[framemethod=tikz]{mdframed} %\usepackage{fancyhdr} ---> ??? \usepackage{microtype}  \renewcommand{\baselinestretch}{.8} \pagestyle{empty}  \global\mdfdefinestyle{header}{% linecolor=gray,linewidth=1pt,% leftmargin=0mm,rightmargin=0mm,skipbelow=0mm,skipabove=0mm, }  \newcommand{\header}{ \begin{mdframed}[style=header] \footnotesize Some Text Inside\\ Page~\thepage~of~6 \end{mdframed} }  \makeatletter \renewcommand{\section}{\@startsection{section}{1}{0mm}%                                 {.2ex}%                                 {.2ex}%x                                 {\sffamily\bfseries}} \makeatother \setlength{\parindent}{0pt}  \begin{document} \footnotesize \begin{multicols*}{5} \header \lipsum\lipsum\lipsum\lipsum \end{multicols*} \end{document}   Is there a way I could achieve this result having the box automatically at upperleft column for each page and no text will be drawn above the box?


Prove by induction that $3\mid n^4-n^2$ for all $n \in \mathbb{Z^+}$, $n\ge2$.

Claim: $3\mid n^4-n^2$  for all $n \in \mathbb{Z^+}$, $n\ge2$. What I've done so far: Base case: Let $n=2$. Then $\exists k \in \mathbb{Z}$ such that $12=3k$, namely, $k=4$. Thus $3 \mid 12$ and hence the claim holds for $n=2$. Assume for positive integer $m \ge 2$ that $m^4-m^2=3k'$ with $k' \in \mathbb{Z}$ I substituted $m+1$ for $n$, and have $(m+1)^4 - (m+1)^2$ $=$  $\sum_{i=0}^{4} {4\choose i} m^i \cdot 1^{4-i} - (m+1)^2= m^4+4m^3+6m^2+4m+1-(m+1)^2=m^4-m^2+4m^3+6m^2+2m=(m^4-m^2)+4m^3+6m^2+2m=3k'+4m^3+6m^2+2m$ I'm stuck. Would this be the correct way to go? Reattempt Proposition: $3 \mid n^4-n^2$ for all $n \in \mathbb{Z^+}, n \ge 2$ Lemma: $3 \mid (m-1)m(m+1)$ Proof. Suppose $m \in \mathbb{Z}$. By the QRT, we have $m=3q+r$ $\,\ni\, r \in \{0,1,2\}$, and $q=\lfloor{\frac{m}{3}}\rfloor$. We want to show that $(m-1)m(m+1)$ is divisible by 3. Clearly, if any one of the three factors in $(m-1)m(m+1)$ is divisible by 3, then the product must also be divisible by 3. $\cdot$ Case 1 ($r=0$): If $r=0$, then $m=3q$ is divisible by 3. $\cdot$ Case 2 ($r=1$): If $r=1$, then $m-1=(3q+1)-1=3q$ is divisible by 3. $\cdot$ Case 3 ($r=2$): If $r=2$, then $m+1=(3q+2)+1=(3q+3)=3(q+1)$ is divisible by 3. In either case, one of the three factors in $(m-1)m(m+1)$ is divisible by 3. Thus $3 \mid (m-1)m(m+1)$. Therefore, the product of any 3 consecutive integers is divisible by 3. Proof. Base case: Let $n=2$. Then $\exists k \in \mathbb{Z}$ such that $12=3k$, namely, $k=4$. Thus $3 \mid 12$ and hence the claim holds for the base case. Assume for positive integer $m \ge 2$ that $m^4-m^2=3k$ for some $k \in \mathbb{Z}$. We need only to show that this implies that $3 \mid (m+1)^4-(m+1)^2$. $(m+1)^4-(m+1)^2= \sum_{i=0}^{4} {4\choose i} m^i \cdot 1^{4-i}-(m+1)^2=(m^4-m^2)+4m^3+6m^2+2m=(m^4-m^2)+3(m^3+2m^2+m)+(m^3-m)$. By the inductive hypothesis, $3 \mid(m^4-m^2)$. And since $(m^3+2m^2+m) \in \mathbb{Z}$, it follows that $3 \mid 3(m^3+2m^2+m)$. Note that $(m^3-m)=m(m^2-1)=(m-1)m(m+1)$. By the Lemma, $3 \mid (m^3-m)$. Thus we have $3 \mid (m^4-m^2)$, $3 \mid 3(m^3+2m^2+m)$, and $3 \mid (m^3-m)$. To show that their sum is divisible by 3, let $k_1,k_2,k_3 \in \mathbb{Z} \,\ni\, m^4-m^2=3k_1, 3(m^3+2m^2+m)=3k_2$, and $(m^3-m)=3k_3$. Thus $3k_1+3k_2+3k_2=3(k_1+k_2+k_3)=m^4-m^2+3(m^3+2m^2+3m)+(m^3-m)$, where $(k_1+k_2+k_3) \in \mathbb{Z}$. Hence $3 \mid (m+1)^4-(m+1)^2$. Therefore, by induction, $3 \mid n^4-n^2, \forall n \in \mathbb{Z^+}, n \ge 2$


India to Glasgow via Dublin Etihad Airways

I am travelling from India to Glasgow via Dublin on Etihad Airways. I am an Indian citizen and have a UK standard 6-months visa (which has not been used before).  The flight from Abu Dhabi to Dublin arrives at Terminal 1, and the connecting flight from Dublin to Glasgow (operated by Aer Lingus) departs from Terminal 2. Do I need an Irish visa for this transfer?  If you have taken a similar flight, please share your experience in transiting from T1 to T2 in the Dublin Airport.