( How-To ) Ultra Low-Profile PCB Stacking

Recently I found myself needing to stack two small circuit boards on top of each other for a modulation project. The problem is that the areas I want to connect together on the two boards have no components or traces on them, and traditional pin-style stack ups (even machine headers) leave an unwanted gap between boards.  How can I stack the boards flush with on another and have a minimal gap between them?  I have seen  which shows an approach to stack boards permanently flush together, but I need a solution that is removable.


Can flying creatures choose to hover, even if they don't have hover in their flying speed?

Some creatures have a fly speed.  Some creatures with a fly speed also have the ability to hover specified.  The PHB, in Chapter 9: Combat, Movement and Position, Flying Movement says:     Flying creatures enjoy many benefits of mobility, but they must also deal with the danger of falling. If a flying creature is knocked prone, has its speed reduced to 0, or is otherwise deprived of the ability to move, the creature falls, unless it has the ability to hover or it is being held aloft by magic, such as by the fly spell.   The conditions in this paragraph that would result in the creature falling have to do with having movement involuntarily removed or restricted.  That might suggest that if you don't have "hover" in your flying speed, you can't hover.  But there is a difference between being knocked unconscious, or frozen, or webbed, or otherwise rendered unable to move, and choosing to hover, by flapping your wings, or standing on your jets, or whatever.  So, can flying creatures choose to hover, even if they don't have hover in their flying speed?


How does supervisor contribute to students' papers

I know my question maybe too broad, but as someone who's planning to stay in academia, I want to ask anyone who is supervising PhD students about how you contribute to their papers in order to be included as authors.  Do you just need to discuss the problem (e.g what is it? Is it feasible or worth to be solved), point them to potential directions and review the drafts? You can also help writing other sections which don't directly involve in solving the problem such as: introduction, motivation or conclusion. This is the approach that my supervisor and most lecturers in my department are taking.  Or, do you have to directly take part in solving the problem such as analysing it, designing system, performing experiments and evaluating results?


Using SED to remove specific line in a conf file

Im running against the wall in this command.. I want to remove the line: include "/etc/nginx/software.conf";  from the file called website. I've tried: sed -ri '/include \"/etc\/nginx\/wesbite.conf\"\;/d' website  A simple sed command works fine.. but all this special letters confuses me. Any suggestions please? Thanks alot.


I'm thinking about upgrading my lens. I am currently using a canon 4000d with its kit lens 18mm - 55mm, as I don't have the money at the minute to upgrade both (want to upgrade to a full frame in the future) I think upgrading the lens would be better than upgrading the body. Does anyone have any ideas on what I could upgrade to? I take specifically landscape photos. I understand that the crop sensor on the 4000d has a crop factor of 1.61 so that means I'm not getting 18mm, I'm getting 28/29mm at its widest. Would be looking for something that's abit wider and better quality! Any suggestions would be appreciated it!


The sum of odd powered real numbers equals zero implies the numbers are inverses

Show that if real numbers $a_1,a_2,\ldots,a_n$ satisfy  $$a_1^l+a_2^l+\cdots+a_n^l=0$$ for every odd $l$, then for any $a_i$ we can always find some $a_j$ (not necessarily different) such that $a_i+a_j=0$.


Given three circles with every two tangent, does there exist a circle between them tangent to all three?

Consider three circles with every two of them tangent. Does there exist a circle between them which is tangent to all three?


Not able to understand difference of function in class & defining it as prototype in Javascript OOP

I'm not able to understand what exactly is the difference by defining the function inside the class function & defining it as prototype. Here is my code.      PART 1  function myContent() {      this.toUserID = "1234";     this.loadMainLabel = function(url) {         alert("url:"+url);     }        }  var objMyContent = new myContent(); objMyContent.loadMainLabel("www.google.com");   PART 2  function myContent() {      this.toUserID = "1234";           }  var objMyContent = new myContent(); myContent.prototype.loadMainLabel = function(url) {     alert(url); } objMyContent.loadMainLabel("www.google.com");   Both gives the same output.. But, what exactly is the difference? Any thoughts would be appreciable.   Cheers!


What do missing an Oxford comma and having it mean respectively here?

in trending says  The highlights of his waning administration include encounters with Rudy Giuliani, a healthcare disaster and a dildo collector.   says  People keep telling me this sentence is a perfect example of the need for the Oxford comma, but I am here to tell you that @BCDreyer knew EXACTLY what he was doing when he wrote this sentence, and I am fully here for it, one hundred percent.  What do missing an Oxford comma and having it mean respectively in the first tweet? (I am having trouble to understand why it is being discussed.)


reverse forking .. extracting a repo from another repo

I have opened a repo on github, started coding after that i found my self building a Generic Application model for the projects in my domain, now i want to extract the application model from my repo to another repo.  i can fork the repo and remove the files related ,particularly, to my project, but i will be miss-using the "fork" operation.  And also this command   git merge origin/upstream   will reproduce my project specific files.  it sounds like a reverse forking .. how to implement that ?


I found my .MobileBackups folder quite large, it weighs 160 GiB. Shouldn't the .MobileBackups folder be wiped after the Time Machine 'backup session'?   Since I have backup done on my external drive how can I get back my 160GiB of HDD space? Can I simply remove this folder or maybe set some limit of mobile backups?


Tax implications of transferring money to retired parents (India)

I transfer some amount of cash to my parents for their groceries every month. What are the tax implications for this amount? Do I get any tax exemptions for this sum?


Find all positive integers $a, b$ such that $3^a = 2b^2 + 1$. This means that $\displaystyle\frac {3^a − 1} 2$ is a perfect square. Then checking for a few small values I get a few solutions as: $(a, b) \in \{(0, 0), (1, 1), (2, 2), (5, 11)\}$ How to proceed to find out all the possible solutions? Please help. High Regards, Shamik Banerjee


Calculating the smoothing capacitor for a power supply

Trying to build a simple 9V power supply using a 7809 voltage regulator and full wave rectifier. The load current from the regulator is 1A. So I = C*dv/dt, therefore,  C = I*t/(delta V)    To my understanding t is the time between the two peaks or the time the capacitor supplies the load. So if t is reduced, shouldn't the ripple increase ?, so isn't ripple (delta V) dependent on t ?, if so then why is delta V just arbitrarily chosen without considering t ?


Why don't we consider jerk in physics classes?

When I got more into physics, I started asking myself if just like acceleration represents the growth of speed, something else could also represent the growth of acceleration itself. And it came that is exists and is called jerk. Before I thought about this, I thought that acceleration was the highest derivative that made sense on physics.  My question is, why can we perform accurate calculations without account for jerk? I never needed it in a single physics class! I've also read that it is seldom used.  Also, while position, speed and acceleration seem familiar to me due to everyday experience, why doesn't jerk seem familiar to me? I never tell someone when driving a car "you're jerking too much", whereas I could say "you are accelerating too much".  Is it that jerk has little influence because it is almost constant? Even if it is not, what about higher order derivatives? Why don't derivatives higher than acceleration have much influence on calculations? We perform a lot of reasoning in everyday life without resorting to it!


Would 'There are 300,000 dollars in my bank account' be correct usage?

Would using there are instead of there is be acceptable in utterances that talk about quantity? For example,        There are 300,000 dollars in my account.    There are 20 gallons of petrol in my tank.


Does $\displaystyle\sum_{n=1}^{\infty} \frac{2^n}{n^n}$ converge?

Hey I'm pretty new to university math and one of my assignments wants me to determine whether this formula converges or diverges. My reasoning was that it is bigger than 1/n and that diverges. so it should diverge as well.


Duplicate contacts in iPhone 4 with two Exchange accounts, one is Lotus Traveler

I have two exchange accounts on my iPhone 4. One that connects to my gmail, the other connects to my work's Lotus Notes. There are no overlapping contacts in the two accounts. There are also no contacts saved locally on my phone.   When I enable contacts in both accounts, I get two identical entries for each of the contacts in my gmail. If I disable the Notes exchange account, then there are no more duplicates. If I have Notes contacts enabled, and gmail contacts disabled then I have no contacts at all.  Does anyone know what is going on? Is this a problem with having multiple exchange accounts or is it a Lotus Traveler problem? (I tend to blame Notes for all the trouble in the world, but that is just my bias)  Thanks all.


I understand monsters only spawn in a 9 x 9 grid of chunks centered on the player, and I assume they stay around while they remain within that distance of you. But do they despawn as soon as you move away from them? Or do they remain? If so what (if anything) causes them to despawn? Are the rules any different for passive mobs?  Will running far away from an area and then coming right back clear it of monsters?


Why is the resulting UV map stretched out when unwrapping my object?

So, I've been unwrapping semi-circular objects and this happens:     I wanted to know if it is a configuration setting that I'm screwing up or something like that. I can edit it but it is a huge pain, in some tutorials they just work. This is killing me slowly and surely.


CSV text files loading error / crash in QGIS 2.18.8

I got a problem when I try to load tab-separated text files in the "Create a layer from the delimited text file" tab (that one with de comma symbol). After normally selecting the X and Y fields and clicking OK, the reference coordinate system (SRC) selector screen appears, then the program closes by itself. I had uploaded more than a hundred of this type of file by the same procedure in the previous version of QGIS (2.14 Essen) and have no problem, but since I updated to version 2.18.8 (Las Palmas) I can not load any files or .CSV type.   Do anyone knows what's happening? Am I doing anything wrong?


find the probability that more than 50 of the observations of the random sample are less than 3

Let X1,X2,...,Xn be a random sample of size n=72 from a distribution with pdf f(x)={1/x2    1<x<infinity 0      otherwise Find the probability that more than 50 of the observations of the random sample are <3 (less than 3).


Tag badges - high relative effort for low reward on low traffic tags

This is a mild annoyance for me. I answer SO questions inside a very specific area. The tags which I answer in the most are very low traffic, and yet I still require 100 up-votes for a bronze badge.   This is inherently unfair. To get a tag badge in a more popular tag would take far less time and effort (and indeed, less depth of knowledge about the subject matter).   I have required 124 distinct answers to amass 100 up-votes in one tag, which has taken me about 15 months. I am an expert in my subject matter but despite this I'm fairly certain I won't ever make the gold badge for that tag.   I would like to see the tag badges awarded on a sliding scale, based on how many other users have the badge (or another, perhaps better, measure of how popular the tag is). This would help incentivise subject matter experts to monitor and answer in the less popular tags.


How to get Ubuntu to ask for my password at login screen again?

I used to have a password prompt but then I, from somewhere in User Accounts, unchecked "Require a password for login." Now, I want Ubuntu to prompt for a password again at login screen, mainly because I have to manually unlock the login keyring whenever I access Dash or other services, which is a pain at best.  I also searched another question, namely . It was of no help because the OP's question is "I have a password but Ubuntu doesn't ask for it."  Also, the two answers provided there don't solve my problem at all. They discuss completely other things.  Is there no simple mechanism? Because intuitively, if there's a checkbox option to bypass password requirement, there should be an equally hassle-free facility to again require the password.


How can I edit/create new launcher items in Unity by hand?

Will Unity allow making custom launcher icons from .desktop files or via menu editing system? (Right now the launcher doesn't give the option to "keep in launcher" on all programs.  For some programs I use, I have to make custom launchers or .desktop files.  For instance, daily blender builds are generally just folders with an executable.  In basic Gnome or KDE, I can make a new menu entry with the menu editing system. Then, I can also add it to Docky either from the menu or by dragging a .desktop file to it. Unity launcher doesn't support drag and drop, so thats not a bug or anything, but when I open a .desktop file, it has unpredictable results. Most time it will not have "keep in launcher". Sometime it will have a pinnable item without the .desktop's icon, and if I pin the item to the launcher, it will not call upon the program again after closing it. I've also gotten it to just work with a .desktop file for celtx.


has some interesting links under Related questions: the links don't have titles.    A little investigation shows that's not surprising; they link to answers instead of questions, and those don't have titles:


How can I tell if my variable is discrete or continuous?


css - What's difference between display:none; and visibility:hidden;?

What's exactly the difference between display:none; and visibility:hidden; they both do the same thing.  What sorcery is that?


An example where the output of the k-medoid algorithm is different than the output of the k-means algorithm

I understand the difference between k medoid and k means. But can you give me an example with a small data set where the k medoid output is different from k means output.


How to add (programatically) a custom icon in the Finder's sidebar favorite list?

When Dropbox (for example) is installed, it adds a “Favorite Item” in the Finder Sidebar Favorite Items List with his own icon and pointing to its custom folder. How do they do it ?  I’ve tried adding with PlistBuddy modifying the com.apple.sidebarlists.plist, but this is too limited, since I cannot add binary data, the bindings, TemplateSystemSelector, and other stuff needed in the array of the dictionary.  Maybe it’s a simpler way through Xcode coding…   Notice that with "Favorite Servers" is easier since it has just a Name and URL, and the icon is not customizable. So I'm not asking about Servers, but Favorites Items ;-)


If all minors are $0$, the rank is at most $n-2$

Can anyone prove/disprove the following statement?  Given a square matrix of size $n\ge2$, if all of its $(n-1)$-rowed minors are zero, then $\operatorname{rank}(A)\leq n-2$.  I'm having trouble connecting the information on the minors to what I have to prove.  Thank you in advance.


what might be defining the $PATH variable?

I'm currently exploring and experimenting with my linux just for fun and educational purposes.  I have deleted the content of the /etc/bash.bashrc and /etc/profile and I don't have any configuration in the home directory for both root and local users, I also perform a reboot.  However when i run printenv PATH the values of the path was still there which is:   $PATH=usr/local/sbin:/usr/sbin:/sbin:/usr/local/bin:/usr/bin:/bin:/usr/games   what might be defining the $PATH?  EDIT:   I forgot to mention that I'm using Kali linux.  I've found one of the culprit is in the /etc/profile.d/kali.sh as mentioned by a guy named flyingdrifter in the comment section of this thread ->  (although his distribution is LinuxMint).   Now the $PATH variable has been reduced to   $PATH=/usr/local/bin:/usr/bin:/bin:/usr/games   which means that there are probably one last file that setting the PATH variable.


My Colombia visa is on my previous passport. Since I have run out of pages, I have obtained a new passport. Can I still travel with both passports and enter the country?


Can workspace switching Ctrl + Alt + Arrows be changed?

Can the workspace switcher be changed so that it works like it used to in 10?  When switching workspaces in Unity you need to use both the horizontal arrow keys, but if you want to get to workspace 3 and 4 then you must use the vertical arrow keys. This is annoying.  Can I change it so that I can access all workspaces by hitting the horizontal arrow keys only?


How do I search for code fragments that are punctuation? For example, how do I search for the strings ||: or ->?

How do I search for code fragments that are punctuation?  For example, how do I search for  ||: or -> ?  Is there a way to search for these sorts of things in StackExchange? Here's what I've already know: Google can find it.  See:  Google's results:  ...    But both  and , can't seem to find these.  (I think DuckDuckGo can't find it because StackExchange can't find it.  , but I'm not sure about just how this works.)


How can I know if terminating chkdsk caused corruption?

, but I came to not sure about this issue and thought I should ask a follow up question to clarify the details.  First, I ran chkdsk /r on drive which got some physical bad sectors. this was my mistake cause of data loss with marking bad clusters, so I canceled chkdsk on stage 4 (bad cluster searching in user files) and 1~3 stages are passed with no errors, in that time chkdsk was working like freezing on stage 4.  So basically chkdsk didn’t show any “Windows replaced bad clusters in file 25702” or any kind of messages on stage 4 while running, I canceled it before chkdsk show the messages.  So my guess are in two ways:   chkdsk didn’t detect any bad cluster, errors at the point when chkdsk running as screen show chkdsk was doing some, fixing bad clusters and just couldn’t show messages for while because i canceled. in this case data is already changed.   I am pointing at possibility of 2.  This issue make me paranoid and I want to know is there any way to make sure, this drive is already gone and I moved all data to new drive after cancel chkdsk. I hope data is not changed but, if there is way to know chkdsk didn’t do anything (yet) to data as prompt screen showed, it is fine. Any advice is welcome to make conclusion.


If $F$ is closed, does there exist a finite measure on $[0,1]$ with support $F$?

If $X$ is a metric space, $\mathcal B$ is the Borel $\sigma$-algebra, and $\mu$ is a measure on $(X, \mathcal B)$, then the $support$ of $\mu$ is the smallest closed set $F$ such that $\mu(F^c) = 0$. Show that if $F$ is a closed subset of $[0,1]$, then there exists a finite measure on $[0,1]$ whose support is $F$.  My Solution:   Let $F$ be a closed subset of $[0,1]$ and $\mu_F$ be defined by $\mu_F(B) = m(B \cap F)$ for any $B \in \mathcal B_{[0,1]}$. Since $F$ is a closed subset of $[0,1]$, it is in $\mathcal B_{[0,1]}$ and $\mu_F$ is a measure. The measure is finite since $\mu_F([0,1]) = m([0,1] \cap F) \leq m([0,1]) = 1$ and since $\mu_F(F^c) = m(F^c\cap F) = m(\emptyset) = 0$, the support of $\mu_F$ is $F$.   My questions:  Why do we need the condition that $X$ is a metric space to define the support?  Is my answer correct?


Difference between theoretical physics and mathematical physics?

I'm a huge fan of mathematical physics and I know what the formal definitions of those  two areas are, I've seen them. But I still get completely baffled when someone asks me to explain it simply. The difference is obvious to me, but I just can't seem to put it into words in a satisfying enough manner. So I'm asking you to help me...  What is the essential difference between  and ?  or if you prefer the rephrased version...  What was the motivation for introducing the name "mathematical physics" as a separate entity?  (It doesn't matter if you're one of those people who don't like labels, the thing is that we do have these two separated very often in academia.)


How to put an acute on an i using Biber: issues with "\'{\i}"

I use some packages with require utf8. Here is the main file:  \documentclass[a4paper,titlepage]{report}  \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usepackage[american]{babel} \usepackage{csquotes} \usepackage[backend=biber,style=alphabetic]{biblatex} \addbibresource{refs.bib}  \begin{document} \nocite{*} \printbibliography[heading=bibintoc] \end{document}   And here is the reference file:  @MISC{Example,     author = {Author with spec\'{\i}al character},     title = {Title} }   I have no issues with composing special characters like \H{o} (ő) or \k{a} (ą). However, when I try to compose \'{\i} (í), I get the following inputenc error: "not set up for use with LaTeX". It seems like double compositions are not allowed. A solution is to use \'{i} instead, but not removing the dot is ugly. Surely there must be a better way?  Note: I have tried to add \DeclareUnicodeCharacter{00ED}{\'{\i}} to the preamble, but it doesn't help either.


Biblatex: nested citations with the \textcites command

I'd like to type a citation within the text and another citation inside the parenthesis for the year, something like this:     The work of Author 1 (year; cited by Author 2, year)   For this, I've tried different options of the \textcite command but without results. Also I saw the solution posted , which works for multiple citations within parenthesis but not for in-text citations.  Any suggestion?


How to return two vectors from one C++ function

I am using  C++ lib, and created two vectors using  std::vector in a function. But how can I return back the two vectors in one function? Is it possible to merge the two vectors into an array or a matrix in order to return them,


What is the difference between "source x", ". x" and "./x" in Bash?

I have one bash source run.sh as follows,  #!/bin/bash if [ $# -ne 1 ]; then     exit fi ...   when I execute it in two ways, there are different behaviors. The first way is,  source run.sh   It will close the terminal after execution. The second way is,  ./run.sh   this will simply finish running the script, and stay on the terminal. I am asking if there is a command for exiting a bash scripts for both source run.sh and ./run.sh execution. I have tried return too, which does not work well under ./run.sh execution.  More generally, I am interested in why this is happening, and what's difference between using "source" and "." for script execution?


Optimal Binning with respect to a given response variable

I'm looking for optimal binning method (discretization) of a continuous variable with respect to a given response (target) binary variable and with maximum number of intervals as a parameter.  example: I have a set of observations of people with "height" (numeral continuous) and "has_back_pains" (binary) variables. I want do discretize height into 3 intervals (groups) at most with different proportion of people with back aches, so that the algorithm maximizes the difference between the groups (with given restrictions for instance, that each interval has at least x observations).  The obvious solution to this problem would be to use decision trees(a simple one-variable model) , but I can't find any function in R that would have "maximal number of branches" as a parameter - all of them divide the variable into 2 gropus  (<=x and >x). SAS miner has a "maximum branch" parameter but I'm looking for a non commercial solution.  some of my variables have just a few unique values (and could be treated as discrete variables) but I want to discretize them as well into a smaller number of intervals.  The closest solution to my problem is implemented in the smbinning package in R (which relies on ctree function from party package) but it has two drawbacks: it's impossible to set the number of intervals (however, you can find a way around it by changing the p parameter) and it doesn't work when data vector has less than 10 unique values. Anyway, you can see the example output here(Cutpoint and Odds columns are crucial):  Cutpoint CntRec CntGood CntBad CntCumRec CntCumGood CntCumBad PctRec BadRate   Odds  LnOdds     WoE     IV 1   <= 272   9081     169   8912      9081        169      8912 0.1874  0.9814 0.0190 -3.9653 -0.6527 0.0596 2   <= 311   8541     246   8295     17622        415     17207 0.1762  0.9712 0.0297 -3.5181 -0.2055 0.0068 3   <= 335   2986     163   2823     20608        578     20030 0.0616  0.9454 0.0577 -2.8518  0.4608 0.0163 4  Missing  27852    1125  26727     48460       1703     46757 0.5747  0.9596 0.0421 -3.1679  0.1447 0.0129 5    Total  48460    1703  46757        NA         NA        NA 1.0000  0.9649 0.0364 -3.3126  0.0000 0.0956   Oh, I'm fully aware that binning results in information loss and that there are better methods, but I'm going to use it for data visualization and treat those variables as a factor.


What are the printing differences between arrays and arrayLists?

I have a question about printing differences between arrays and arrayLists.   Why am I able to use System.out.println(points) and System.out.println(intsArrayList); to print out the points stored in the arrayList and the Integer wrapper class, but I cannot do the same for points stored in arrays or integers stored in arrays? Why can I print the entire ArrayList using System.out.println but I can't print the entire array using System.out.println? The following is my code.  package practice; import java.util.ArrayList; import java.awt.Point;  class Main{     public static void main(String[] args) {         ArrayList<Point> points = new ArrayList<Point>();         points.add(new Point(10,20));         points.add(new Point(30,40));         points.add(new Point(50,60));         System.out.println(points);          Point[] points1 = new Point[5];         points1[0]=new Point(70,80);         points1[1]=new Point(90,100);         System.out.println(points1);          int[] intArray = new int[]{ 1,2,3,4,5,6,7,8,9,10 };          System.out.println(intArray);          ArrayList<Integer> intsArrayList = new ArrayList<Integer>();         intsArrayList.add(new Integer(1));         intsArrayList.add(new Integer(2));         intsArrayList.add(new Integer(3));         intsArrayList.add(new Integer(4));         intsArrayList.add(new Integer(5));         System.out.println(intsArrayList);       } }   The following is my output:  [java.awt.Point[x=10,y=20], java.awt.Point[x=30,y=40], java.awt.Point[x=50,y=60]] [Ljava.awt.Point;@70dea4e [I@5c647e05 [1, 2, 3, 4, 5]   edited for typo.


Will deadlocks occur when deleting rows from a table when being added to by another process?

I have to archive data from a table into another table whilst the original table is in use.  The archival process is to copy the rows into another table and then delete the rows from the original table.  The rows to be archived are selected by a column that has the Identity property.  A factor is that the table from which the rows are being archived will be in use - new rows will be written into the table as the archival process is running.  This is a 24/7 application that cannot be stopped.  The rows that are being deleted are at the low end of the Identity column numbering whilst the new rows will be being added at the end of the table.  My concern is deadlocks.  Is there a chance that deadlocks could occur between the 2 processes?   The archival process will be run from a Stored Procedure?  Should I set the DEADLOCK_PRIORITY to LOW to ensure that if a deadlock does occur that the archival process will be killed and not the running application?  Should I also set TRANSACTION ISOLATION LEVEL?  Thanks


Possible impact of antimatter on space-time?

Is it possible somehow that antimatter (-ve mass) could create an upside curvature on spacetime, as it bulges outward rather than inward as in case of real matter (+ve mass)?


How to deal with 100+ levels in categorical variable in multiple linear regression?

Im trying to model: Y~x0+x1+x2+x3+x4, were Y is a continous variable (cost), x0 is the intercept, x1 is a continous variable (days) and x2-x4 are categorical variables with mulitple levels. The categorical variable x2 have 156 levels (each level representing a different diagnosis code, i.e. lung cancer, migraine etc). I want to include x2 in the model but I dont want 156 different dummy variables, were each dummy variable represent a diagnosis code.   Here is a picture of the frequencies of each level (censored):   About 2/3 of the levels are significant at 0.05, when Y~x2.  What is the best way to deal with this kind of problem in R?


Start up pre logon wallpaper location/infomaiton?

I really like the image that comes up right now, but how do I find out WHAT image it is and WHERE his picture was taken?? If I can find the image, I can find the location.


Download games from steam to another drive

I'm having a little trouble to get Max Payne 3 installed on my pc. The trouble is that I have only 20 gb of free space left on my ssd where my steam is installed, and there is no way for me to create extra room. Now the Max Payne 3 game is about 30gb in size.  But because it is so big, there is no way for me to download the game. What i would usually do is download the game and then cut and paste it to my other drive and make a symlink.   But because there is no way for me to download the game I can't do that. Is there a way for me to trick steam into thinking that it is installing/downloading the game on my ssd while it is actually doing that to the other drive?


I just submitted a bounty on a question and I typed a custom reason. Here is what I saw:  I know that I typed the bounty message correctly, because it . This is only a problem with the display of the bounty message submission box. I am using Firefox 24.0. Notice that not only is what I've typed corrupted, but also the leftmost characters in the number of characters remaining and the Enter a custom... header and the Are you sure... message and the Back button are also cut off.


I'm going to the dry cleaner's - why the apostrophe S?

"Dave's car" means the "car of Dave".   But why do we need the apostrophe S in: I'm going to the dry cleaner's ?  Is there another way to say this phrase? For example: I'm going to the establishment of the dry cleaner? (that sounds completely off to me).


Allow 10k to vote to delete on locked rejected migrations

While wandering through Software Engineering Stack Exchange, sometimes a close vote finds its way onto a question from Stack Overflow that was migrated back in '11 and it gets closed.  When this happens:   The question is locked All answers from Stack Overflow are deleted   This, in of itself, isn't a bad thing, but it is locked now.  This means that a 10k user cannot vote to delete on it, nor will the automatic deletion scripts act upon it.  The only way to clean up this question (which might not have any answers on it anymore) is to flag it for moderator action.  I've got more than a few helpful flags from this... but it really isn't all that much 'fun' bugging the moderators over very routine janitorial duties that 10ks should be able to do themselves... And I'm sure the mods are bored reading the "this is a locked rejected migration"  The request: Allow 10k vote to deletes to be cast upon question that was locked as part of a rejected migration.  If you really want to be nice, allow 20ks to cast vote to undelete on the answers.  Sometimes things need to be closed, but some answers need to remain if the question isn't of the type that should get deleted wholesale.    Should the roomba scripts clean these up automatically regardless of other conditions?  No.  There is nothing broken with the roomba as to how it handles rejected migrations - there's nothing special about them, other than that they are locked.  There are many possible reasons for a rejected migration.  It could be too broad.  It could be unclear.  It could be a any of the local off topic reasons.  Expecting the roomba to delete these questions (positive up vote, has an answer)  is incorrect - rejected migrations are closed questions and its as 'simple' as that.  One solution to this would be to make it so the migration isn't locked when its rejected.  This would:   Allow 10k to delete Allow people to down vote (and feed the roomba) Allow people to edit (and make into a reopenable question)   Whatever the case, when there's a question I'm going to cast a close vote on that happens to be a migration that should get deleted currently the workflow is "notify a mod that I've close voted it so that they can delete it because I can't..." (see  (Software Engineering 10k link))  And if it shouldn't get deleted, its a "wait until it closes, flag it to unlock it and undelete various answers that are actually not bad" (see  and )  Note that another solution to the request above is: Don't lock rejected migrations on the target site, which would also solve a number of issues... though it was done for a reason and I'm not completely sure of the business requirements behind that.


Proof there is an irrational number $r$ in every intervall $a < r < b$

Proof that for $a,b \in \mathbb{R}$ there is an irrational number $r$ so that   $a < r < b$. Basically, proof, that between any two irrationals, there is another irrational r.    I'm sure there are already many ways out there how to do it, however I have troubles proving it in the following way:  (1) For every $x,y \in \mathbb{R}$ there is a bijective function between $[0,1]$ and $[x,y]$ (already proven)  (2) $\frac{\sqrt{2}}{2} \in ]0,1[$  (3) Now  when mapping $[0,1]$ onto $[x,y]$ $\frac{\sqrt{2}}{2}$ will also be mapped into the new intervall, therefore there has to be an irrational number in $[x,y]$  Now the problem I see is, that for example $\frac{\sqrt{2}}{2}$ could be mapped onto a rational number and therefore I'd have to proof, that there is a different irrational in $[x,y]$. It'd be nice if you could help me complete the proof.


I am just being introduced to logic in mathematics. Let $P$ be "He is an honest person." and $Q$ be "He can be the President.". My lecturer was saying that "only if" means $P\rightarrow Q$, while "if" means $Q\rightarrow P$. I simply cannot wrap my head around this.  So let us consider the following two sentences.   One can be the president only if one is honest. One can be the president if one is honest.   How are the two statements any different in meaning?  However, according to the definitions, the first statement is of the form $P\rightarrow Q$, while the second is of the form $Q\rightarrow P$ and I know that $P\rightarrow Q$ and $Q\rightarrow P$ clearly have different meanings.  Any explanations regarding the difference between both terms and how/when to use which will be greatly appreciated!


How to create a method that exchanges the location of two class variables?

I'm trying to create a method that can exchange the location/reference of two class variables, but I can't change the reference of the class variable that is calling the method (this), so I'm wondering is there any way to get around this.  public void exchange(Card x) {     Card y = this;     this = x;  //this doesn't work     x = y;  }


Where did Sauron go after his defeat in the Second Age?

Sauron was defeated in the War of the Last Alliance and his spirit fled from his body. Where did he flee away and hide for thousands of years? Are there any details as to where he went or is it just plainly 'his spirit left his body and didn't return until the Third Age'?


Do gravitational lenses have a focus point? Could I burn space ants?


Retrieve increments of rows from multiple rows

I am trying to find a way to retrieve a subset of rows from multiple rows returned; and increment through the subset.  So as an example:  Table A as 1000 records. I do a select * to retrieve all records, but I only want the first 100. Then, I want subsequent queries to return the next 100, and so on, until I reach the end (1000'th row).  If anyone knows how to do this please advise.  Thanks in advance.


Centering a picture in the background of beamer

How to make the figure logo centered in the background, its a circle \documentclass[aspectratio=169,xcolor=table]{beamer}  \usepackage{tikz}      \newsavebox\mybox     \savebox\mybox{% \setstretch{1.0}         \tikz[opacity=0.1]\node[align=center]{%                     \includegraphics[width=7cm]{logo} \\            };     }      \usebackgroundtemplate{     \usebox\mybox}  \begin{document}  \begin{frame}    \end{frame}    \end{document}


As you can see, it starts bugging up, it's pretty hard to explain it, but look at the picture.  Demo:     Markdown:  **http://url.com/user?u=__username__**


I was told that the dynamic library is good because it can save RAM, it's only needed while the program is running.  Now I have a question: if a program can be executed, can I say that all of dynamic libraries that it needs have been there (there wouldn't be any dymanic librariy missing error)?  Saything that a program comes from a link of three .o files, and each .o file needs a dymanic library. If I remove one dynamic library, can I still make the program run?  As I know, we have two ways to load a dynamic library:   Load a dynamic library when we link object files, for example, g++ a.cpp -ltest, here we link the dynamic library libtest.so to our program, if we remove the libtest.so, we would not be able to execute the program. Load a dynamic library with the system api function: dlopen. In this case, as my understanding, if the execution of the program doesn't touch the code of dlopen, we would not have any error.   If I'm correct, could I say if the execution of the program has no error, it means all of dynamic libraries it needs are definitely there?


What is the difference between apt-get and aptitude?

Can anyone please tell me difference between 1 and 2   sudo apt-get install vlc  sudo aptitude install vlc   I tried installing vlc with 1 and it did not work, but with 2 it did. I don't get the difference...


Possible Duplicate:          I have doubt to this problem., $X=(0,\pi/2)$ and the metric is $d(x,y)=|\tan x-\tan y|$ is it complete metric space?  I took one example $x_n=\frac{1}{2^n}$ is a cauchy sequence in $X$, $d(x_n,x_m)=|\tan\frac{1}{2^n}-\tan\frac{1}{2^m}|\rightarrow 0\notin X$, so it is not complete?


I am trying to figure out how to do the infinite summation:  $$ \sum_{n=0}^{\infty} n x^n \qquad 0 \leq x < 1$$  The series converges so it seems to me that the limit must exist, but I'm having difficulties trying to find an exact answer for it. It is very much like an infinite geometric series, but the multiplication factor $n$ makes that you can't use the usual trick. The furthest I came was writing it out as:  $$ x + 2 x^2 + 3 x^3 + 4 x^4 + \dots$$  but that doesn't get me anywhere. Can someone give me a hint?


jquery - Click event not working for dynamically created button

My requirement is to create number of buttons equal to the json array count. I was successful in creating buttons dynamically in jquery. But the method in .ready function of jquery is not called for the click action. I have tried searching in SO. Found few solutions but nothing worked for me. I am very new to jquery. Please help...  my code: jQuery:  $(document).ready(function() {     currentQuestionNo = 0;     var questionsArray;     $.getJSON('http://localhost/Sample/JsonCreation.php', function(data)     {            questionsArray = data;         variable = 1;             //CREATE QUESTION BUTTONS DYNAMICALLY ** NOT WORKING         for (var question in questionsArray)         {             var button = $("<input>").attr("type", "button").attr("id", "questionButton").val(variable);              $('body').append(button);                          //Tried using .next here - but it dint work...             //$('body').append('<button id="questionButton">' + variable + '</button>');             variable++;         }         displayQuestionJS(questionsArray[currentQuestionNo], document);     });         $("button").click(function()     {          if ($(this).attr('id') == "nextQuestion")         {             currentQuestionNo = ++currentQuestionNo;         }         else if ($(this).attr('id') == "previousQuestion")         {             currentQuestionNo = --currentQuestionNo;         }          displayQuestionJS(questionsArray[currentQuestionNo], document);      });    function displayQuestionJS(currentQuestion, document)  {     document.getElementById('questionNumber').innerText  = currentQuestion.questionNumber;     document.getElementById('questionDescription').innerText  = currentQuestion.quesDesc;     $('label[for=optionA]').html(currentQuestion.optionA);     $('label[for=optionB]').html(currentQuestion.optionB);     $('label[for=optionC]').html(currentQuestion.optionC); }  HTML content <form method="post" name="formRadio">  . &nbsp;
 <input type="radio" id="optionA"> </input>
 <input type="radio" id="optionB"> </input>
 <input type="radio" id="optionC"> </input>
  <button id="previousQuestion">Previous Question</button> <button id="nextQuestion">Next Question</button>

  <input type="submit" id="submitButton" name="submitTest" value="Submit"></input> </form>   EDIT -- Sample .on Method code - Separate file: WORKING - THANKS A LOT       <button id="button">Static Button</button>


How to insert a nice tilde in a lstlisting?

How do I insert a nice tilde that is centered in the middle in a lstlisting? I found another thread about  but I can't apply it because the method described there only works outside of lstlisting as lstlisting displays all the text literally. Any ideas?  Here is how the tilde looks in my document at the moment - it's at the very top of the font and I would like it to be in the middle (like ~ this).    Here is the LaTeX for this fragment:  \section{Remove duplicate, consecutive lines (emulate "uniq")}  \begin{lstlisting} awk 'a !~ $0; { a = $0 }' \end{lstlisting}  Variables in Awk don't need to be initialized or declared before they are being used.


How/Where do I check my ubuntu laptops's CPU usage?


Is there any Android distribution statistic for single countries?

I'm looking for statistics for android distributions for individual countries but the main source of information, , only have information for the entire world. There was also  but it hadn't really received a satisfying answer (it points to a blogpost with statistics for specific apps which is not terribly useful).  If I'm making an app for a single country I need information about what distributions are being used in that country. Google doesn't seem to be releasing such information, even if we were willing to pay for it (which we might if pricing was reasonable).


Threading Confusion/Unexpected Behavior: wrong parameter value received when creating threads in a loop

Update 19.June.2020: Alexei Levenkov suggested  - my issue may have nothing to do with threading. I've been using C# for almost 20 years and never knew this and have never knowingly been affected by it. Now I'm a little worried about everything that I've ever done...Thanks Alexei! I have some C# code that creates threads to pass parameters to a method to page through some data. One of those parameters to the method is the counter for the loop that creates the threads. Using Console.WriteLine(), I can see that the value to pass to the method is 0 on the first iteration, but the method receives 100, which is the value of the increment for the loop, as if it's receiving the value after the subsequent iteration of the loop or the iterations are sharing a framestack or whatever somehow. It seems impossible because skup is just a value type int. I do not have this problem when Repository.Configuration.UseThreading is false. I am not very familiar with threading, so I wonder what I have told it to do that could cause this. I tried creating an Int32 from skip just to pass to the method but had the same result. Whatever the issue is, it's hard for me to understand the consequences where I pass other parameters. The first thing the method in the thread does is show the value that it recives, which is 100: private void LoadBatch(EntryPointer entryPointer, ContentTypeWrapper contentTypeWrapper,     int skip, Action<EntryPointer> action) {     Console.WriteLine("LoadBatch: " + skip);     //...  Here is the code that creates the threads: foreach (ContentTypeWrapper contentTypeWrapper in contentTypeWrappers) {     if (contentTypeWrapper.EntriesLoaded == contentTypeWrapper.EntryCount)     {         Repository.Instrument.Warn(this, $"contentTypeWrapper.ContentTypeUid"             + $" already loaded or {contentTypeWrapper.EntryCount} entries; skip");         continue;     }      for (int skip = 0; skip < contentTypeWrapper.EntryCount;         skip += Repository.Configuration.QueryLimit)     {         if (Repository.Configuration.UseThreading)         {             new Thread(() => LoadBatch(entryPointer, contentTypeWrapper, skip, action))                 .Start();         }         else         {             LoadBatch(entryPointer, contentTypeWrapper, skip, action);         }     }  If I make this change, it works the way that I would expect: for (int skip = 0; skip < contentTypeWrapper.EntryCount;     skip += Repository.Configuration.QueryLimit) {     int mySkip = skip;      if (Repository.Configuration.UseThreading)     {         Console.WriteLine("Passing to LoadBatch: " + mySkip);         new Thread(() => LoadBatch(entryPointer, contentTypeWrapper, mySkip, action))            .Start();


A number with an interesting property. $abcd=a^b c^d$

I am finding a 4-digit number $abcd$ (in base-10 representation) satisfying the following property.  $$abcd=a^b c^d$$  I have been running my mind around this problem since a long time, but got no success.  I wrote a python program for a number with this property, and got the answer to be $2592$ since   $$2592=2^5\times 9^2$$  But I am looking for a purely mathematical way to solve this problem.   Thanks!


A word for realising the insignificance of human life against the scale of the universe and enjoying it

A man sits on a bench considering his woeful burden. He looks up at the stars and compares the distance from here to his house and here to the furthest visible star Deneb. Suddenly his problems seems pitifully faint and untroubling. He laughs and relaxes in his seat, staring at the ducks.     Look again at that dot. That's here, that's home, that's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there—on a mote of dust suspended in a sunbeam.   ~Carl Sagan      I really believe that if the political leaders of the world could see their planet from a distance of 100,000 miles their outlook could be fundamentally changed. That all-important border would be invisible, that noisy argument silenced. The tiny globe would continue to turn, serenely ignoring its subdivisions, presenting a unified façade that would cry out for unified understanding, for homogeneous treatment. The earth must become as it appears: blue and white, not capitalist or Communist; blue and white, not rich or poor; blue and white, not envious or envied. ~Michael Collins, astronaut   I'm looking for a noun or verb that describes this positive enlightening experience.


Pagination for 'Type to find users' results does not work

On , type a couple letters ("Jo" for example), then click on [2] or [Next].  This takes you to , which is the second page of all users sorted by reputation, not the second page of usernames containing the search text.


Parse Json object using jquery or javascript

Below is the response I am getting from one of my authentication API.  {"auth":"413e193fe7d10011230b:cea7abe015a6c8d2a78c8dbb48a21f769f65e79441809e918d6e7e98913aeca3","channel_data":"{\"user_id\":\"969696\",\"user_info\":{\"name\":\"Sandra Smith\"}}"}   I would like to get values user_id and user_info from the above response using jquery or javascript. How can I do that?


Should the Citizen Patrol badge be grouped with Deputy and Marshal badge

On the  page in HelpCenter in the section Moderation Badges, the Citizen Patrol batch is listed alone and not grouped with the Deputy and Marshal badge, that are also awarded for flagging.  Should it be grouped? The badges for editing (Editor, Strunk & White, Copy Editor) are grouped.  Or is the Citizen Patrol badge awarded for flagging no matter if the flag is helpful or not?


Filtered questions counter not showing number new questions

I have created some filters in the  section of StackExchange. Normally, it displays the number of new questions next to the list in a way: my list (23)  However, it does not happen now since few days, even though there are new questions matching the filter. I see this happened some time ago  but not pinging the answerer since he did not connect for two days now and he is "formerly a dev at Stack Exchange :)".


How do I reopen a question with has an accepted answer that is obsolete or broken?

There are questions which have accepted answers but the answers are either irrelevant to the present day context (though the question is still relevant) or link to web pages that no longer exist.  Here is an example of a question answered with a dead link:    Here is an example of a question answered with a solution that is no more applicable today (the answer targets an obsolete version of the subject application while the question does not specify the version):    I am interested in getting up-to-date answer to both the questions. Can they be reopened?


Outlook signatures location suddenly changed

I have an installation of Outlook 2010 that used to look for signature files in %appdata%\Microsoft\Signatures. However, recently it created a folder in Application Data\Microsoft\Signatures in the user profile folder and started using that instead.  As I use another application that uses the Outlook signatures in the AppData folder, I need them to be there.   Why did the location suddenly change to the Application Data instead of the AppData folder? How can I revert to the old settings?   I have checked the registry key that sets the folder to a different location, this is set correctly.


Is there a difference between a photo taken using GND filters or applying exposure blending in PP and the HDR technique?


My question is should an airline staff have checked the visa before issuing a ticket?

My brother bought a ticket directly from an airline office. He is a US citizen, but when he arrived at the airport, the airport staff offloaded him and gave the reason as his Pakistani visa was expired. When we came back to the airline office we asked why they did not check his visa before issuing the ticket. The airline staff said that this is not their responsibility. That it is always the traveler's responsibility. Can you please tell me if the staff is right?


ubuntu 18.04 apt-get upgrade problem "redirection loop encountered."

I have recently upgraded from Ubuntu 16.04 to 18.04. Now, when I run apt-get upgrade, I get the following error.  larry@VUbuntu15:~$ sudo apt-get upgrade [sudo] password for larry:  Reading package lists... Done Building dependency tree        Reading state information... Done Calculating upgrade... Done The following packages have been kept back:   linux-generic linux-headers-generic linux-image-generic The following packages will be upgraded:   libvte-2.91-0 linux-libc-dev 2 upgraded, 0 newly installed, 0 to remove and 3 not upgraded. Need to get 1,146 kB of archives. After this operation, 0 B of additional disk space will be used. Do you want to continue? [Y/n] y Err:1 http://192.119.223.46:80/data/0116fed259cd0925/us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 libvte-2.91-0 amd64 0.52.2-1ubuntu1~18.04.2   Redirection loop encountered Err:2 http://192.119.223.46:80/data/011634d2c0cdf482/us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 linux-libc-dev amd64 4.15.0-30.32   Redirection loop encountered E: Failed to fetch http://192.119.223.46:80/data/0116fed259cd0925/us.archive.ubuntu.com/ubuntu/pool/main/v/vte2.91/libvte-2.91-0_0.52.2-1ubuntu1~18.04.2_amd64.deb  Redirection loop encountered E: Failed to fetch http://192.119.223.46:80/data/011634d2c0cdf482/us.archive.ubuntu.com/ubuntu/pool/main/l/linux/linux-libc-dev_4.15.0-30.32_amd64.deb  Redirection loop encountered E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?   If I run sudo apt-get update --fix-missing, I get the same errors.  What does the "Redirection loop encountered" mean? How can I fix this error?  No problems with apt-get update. The sources.list file seems to be OK.


So what I am trying to prove is for any real number x and natural number n, prove $$x^n-1=(x-1)(x^{n-1}+x^{n-2}+...+x+1)$$   I think that to prove this I should use induction, however I am a bit stuck with how to implement my induction hypothesis. My base case is when $n=2$ we have on the left side of the equation $x^2-1$ and on the right side: $(x-1)(x+1)$ which when distributed is $x^2-1$. So my base case holds.   Now I assume that $x^n-1=(x-1)(x^{n-1}+x^{n-2}+...+x+1)$ for some $n$. However, this is where I am stuck. Am I trying to show $x^{n+1}-1=(x-1)(x^n + x^{n-1}+x^{n-2}+...+x+1)$? I am still a novice when it comes to these induction proofs. Thanks


I am trying to insert a list/enumerate(aligned with bullet points) in a tabular environment like this . However, my current code is only able to achieve .   My current code is:   \documentclass{article} \usepackage{multirow} \usepackage{siunitx} \usepackage{tabularx} \begin{document}    \begin{table}[htp] \centering \begin{tabular}{|c|c|} \hline  Date & Tuesday 21/01/2020 \\ \hline  Location & Fraser Noble building; Room FN112  \\ \hline  Start time & 10:00  \\ \hline  End time & 12:00  \\ \hline   \multirow{5}{*}{Present} & Samuel Panza (Scribe) \\           & David Agyeman \\            & Denzil Matthews \\           & Christopher Hyde \\           & Nay Htet Hein \\ \hline  Absent with apologies & Ifeanyichukwu Samuel Anene  \\ \hline Absent without apologies & - \\ \hline Agenda & Initiation of Development of dry base case \\ \hline  \multirow{5}{*}{Items of Discussion} & Identification of the design specifications of dry stream \\ & base case and the initiation of the development of a \\ & design that separates a  dry stream into a HP gas stream \\ & at 200 bara gas with a maximum cricondenbar of 110 bara, \\ & and an oil stream with a true vapour pressure 0.95 bara at 37.8\si{\celsius} \\ \hline  Actions undertaken & \\ \hline  Next meeting & Thursday 23/01/2020 16:30 - 19:00 \\ \hline \end{tabular}  \end{table}   \end{document}


Let $a,b,c,d$ be real numbers such that $a<b < c<d$. Express the set $[a,b] \cup [c,d]$ as the difference of two sets

I am not sure how I would express these sets as a difference. My original attempt was to show that it is the set $[a,d]$ and take away the universal set. I would appreciate any help. Thank you in advance.


All polynomial parametric curves in $k^2$ are contained in affine algebraic varieties

I have started working through the textbook Ideals, Varieties, and Algorithms by Cox, Little, and O'Shea and I am stuck on one part of an introductory question.  The question begins by getting one to show   (1) If $f(t)$ and $g(t)$ are polynomials of degree $\le n$ in $t$, then for $m$ large enough, the monomials  $$[f(t)]^e[g(t)]^f$$ with $e+f\le m$ form a linearly dependent set in $k[t]$.  The next part of the question asks one to deduce      (2) If $C\,:\,x=f(t),\,y=g(t)$ is any polynomial parametic curve in $k^2$, then $C$ is contained in $\textbf{V}(F)$ for some $F\in k[x,y]$.   I have demonstrated (1), but I am at a loss as to how to use that fact to prove (2). It doesn't seem like it is supposed to be a hard problem, but never the less I am having trouble wrapping my head around it. Additionally I assume that for (2) we are not interested in the trivial solution $F=0$.  [Added for completeness]  To do part (1), we recognize that if $\deg(f),\deg(g)\le n$, then $$\deg\left([f(t)]^e[g(t)]^f\right)\le ne+nf\le nm$$ Hence if we have more than $nm+1$ polynomials of the form $[f(t)]^e[g(t)]^f$ then we have a dependent set (since $d+1$ is the dimension of the vector space of polynomials of degree less than or equal to $d$). Now we simply count the number of polynomials in this form (this was an exercise before the problem) - it is $\binom{m+2}{2}=\frac{1}{2}(m+1)(m+2)$ from a standard application of . Ensuring $m$ large enough (specifically $m>2n-3$) gives us the conclusion.


I am newbie to Mac world! After unzipping the apache-maven binaries, I was trying to check its version from the terminal using a command, mvn -v But there I saw message restricting me its access, here is the screen shot.  Do I need to have any other permissions to access this?


How to find an exponential generating function if we know a usual generating function?

Suppose we know a usual generating function of a sequence $a_0,a_1, a_2 \ldots :$ $$ f(x)=a_0+a_1 x+a_2 x^2+\cdots, $$  Question. It is possible to find an exponential generating function for the sequence $a_0,a_1,a_2 \ldots  $ if we know its usual generating function?


Was Albus Dumbledore actually testing Harry in Book 1?

Towards the end of Book 1, Albus Dumbledore takes a broom to the Ministry of Magic whereas he could have Apparated. Then he somehow decides to return midway and simply knows Harry went after the stone without anyone needing to inform him and just arrives in time to take Harry to the infirmary.   Then there’s the fact that despite being able to detect magical signatures he failed to recognise Lord Voldemort’s presence. Also we have to ponder the nature of the obstacles: Fluffy, Devil's Snare, Flying keys, A Giant Chess Board, A test of logic and finally the Mirror of Erised. Harry receives a flute on Christmas from Hagrid, Devil's Snare is a plant known by first-graders, Harry is an amazing Seeker, Ron is a chess prodigy and Hermione is the smartest witch of their year. Does this seem like a set-up to you? Was Dumbledore risking Harry's life to test if he was capable enough? All facts recounted from memory so obviously I failed to add the specific quotes and some facts may be wrong but I believe most of them are right.


HP Pavilion complains about Bitlocker saying TPM is not found. Is there a setting that I need to enable in the motherboard or is there an update for it?


`find` with multiple `-name` and `-exec` executes only the last matches of `-name`

When I'm using  find . -type f -name "*.htm*" -o -name "*.js*" -o -name "*.txt"  it finds all the types of file. But when I add -exec at the end:  find . -type f -name "*.htm*" -o -name "*.js*" -o -name "*.txt" -exec sh -c 'echo "$0"' {} \;  it seems it only prints .txt files. What am I doing wrong?  Note: using MINGW (Git Bash)


Integral with trig functions and substitution

How to integrate: $\int_0^T\cos(T-s)\sin(s)ds$? I was trying to use $\cos(a+b)=\cos a\cos b-\sin a\sin b$ and substitute $\cos(s)=u \Rightarrow \sin(s)ds=du$ but it does't help.


The phrase for when: working in a group to divide responsibility and reduce malicious intent

I am trying to think of what the name of the word/phrase is for when: An important task (not a difficult one, but a mission critical one) is at hand and instead of one person being assigned to it, a group takes on the responsibility to mitigate any consequences happening to one person in case something goes wrong and also to prevent a mistake or malicious intent occurring from one persons doing. (NOT because the task is big and needs to be divided in a group.) E.g.   Two different people needing to turn a key each in a device simultaneously to launch a missile.  Group of people tallying up votes for an election in case one of them were bridged to rig the outcome.


Is there any way to have an image on an html page default to another image if the original source isn't there?

I have a website with images of people.  Sometimes the server with all of the images goes down and my website shows broken image links.  I wanted to see if there is anyway on a webpage to have the following logic where you src one picture but if it doesn't load properly then default to another picture as a backup?  I am fine if it requires js or jquery, etc . .


Why do the terminal attributes look different from outside the terminal?

If I open up a terminal (xfce4-terminal 0.6.3, but I doubt it matters) and I look at what terminal attributes are set (BASH is running in the terminal),  $ stty -a speed 38400 baud; rows 24; columns 80; line = 0; intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = M-^?; eol2 = M-^?; swtch = M-^?; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; discard = ^O; min = 1; time = 0; -parenb -parodd -cmspar cs8 hupcl -cstopb cread -clocal -crtscts -ignbrk brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc ixany imaxbel iutf8 opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0 isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke -extproc   then I have a whole bunch of terminal attributes. Fine enough. If I then take a look at what terminal I'm using:  $ tty /dev/pts/0   then, on a new tab of my terminal (which new tab happens to be /dev/pts/1) I look at the terminal attributes of my first terminal, it seems to have slightly different terminal attributes:  $ stty -a -F /dev/pts/0 speed 38400 baud; rows 24; columns 80; line = 0; intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = M-^?; eol2 = M-^?; swtch = M-^?; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = <undef>; discard = ^O; min = 1; time = 0; -parenb -parodd -cmspar cs8 hupcl -cstopb cread -clocal -crtscts -ignbrk brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl ixon -ixoff -iuclc ixany imaxbel iutf8 opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0 isig -icanon iexten -echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke -extproc   Notably, the original terminal here appears to not be in canonical mode, it has no literal next special character...  So why does this happen? I'd like to be able to look at things like this to see, e.g., if modern ed uses canonical mode, but if there's a Heisenberg problem of looking at it from another terminal, I don't know how I'd do it.  So, my two main questions:   Does the terminal just appear to have different attributes when I look at it from another terminal? (e.g. is my first terminal still in canonical mode, but stty -a -F returns incorrect information?) If the terminal does really change attributes when I switch to the other terminal, how does it know? Is the 1st terminal somehow informed when I'm not directly looking at it?   P.S.: I tried this on the Linux Console also, just to make sure it wasn't a pseudo-terminal thing. Same results.


When is the proper time to use the word "persons" in a sentence instead of using "people"?


Everytime I start my MacBook Pro (which is set to automatically boot into my account) I get the error message "unable to unlock login keychain" with 3 options - continue (which will give me errors as I use my computer whenever I need the login keychain) create new keychain (I know this creates a new keychain, but does it copy all my keys?  Or are they lost now?)  or Update keychain password.  I've used the password which I think should work, but it doesn't.  Now my machine auto logs in, and I get the error, and at the moment I'm clicking continue.  I've tried using keychain repair, which finds no errors.  Please: How should I trouble shoot my keychain errors?  How do I fix my keychain errors?  Is there any way to keep all my old passwords, or have I lost those?


Why did Morgoth curse Hurin instead of killing him? Was it because he knew that if he killed him he would never be able to find Gondolin?


InDesign CS5: Placeholder for "number of pages in a document"?

Much as I loathe Microsquish's Word, it does allow you to insert into a header or footer the automated text "Page X of Y."   When using InDesign, it's easy to set up the "Page X" part on a master page. But is there any placeholder character for the Y? That is, it will count the number of pages in the document, either in an absolute or a relative-to-the-section fashion? Every now and again I narrowly miss sending out something with a footer which reads "Page 4 of 3," and I would love to know if there's some way around that.


Calculating the probability of a function being real when it has random variables

I'm trying to calculate the probability of   $ax^2+bx+c$ root being a real number when the variables $a,$ $b,$ and $c$ values are all randomized by throwing a standard die.   I got to the point where I can get the probability by calculating the chance of $b^2-4ac>0$, but I'm not sure how I can conveniently carry on from here and my attempts at doing it by hand (finding every possible real occurrence and calculating them by the total outcomes) have failed me.   In other words, the values of $a$, $b$ and $c$ are within $\{1,2,3,4,5,6\}$ and each of the three variables is randomly picked from that list with no special weighting (so $\frac 16$  chance to get any of the $6$ values).


I wrote a script (replace.sh) that replaces a ~ with ~\n. I was wondering how can I call this script with multiple arguments.  #!/bin/bash  for i in "$*"  do   sed 's/~/~\n/g' "$i" done   For example I would like to call ./replace.sh text1 text2. It cannot read   the contents of text1 are: 1 ~ 1 ~ 1. After calling the script it should be  1 ~ 1 ~ 1 ~


Okular does not want to open pdf's saved through Zotero

I am very new to Linux / Ubuntu and have been playing around with it for the past week. I have come across a problem I can't seem to fix.  If I want to open a PDF with Okular, which has been stored / filed through Zotero, I get the following message:   Could not open file:///home/ingrid/snap/zotero-snap/common/Zotero/storage/GI4FVK9I/Vranken - 2020 - Rooted Hauntology Lab Attempts at vegetal curatio.pdf   The only program that can open the files seems to be pdf viewer, but this does not have the functionality I need.  Thank you for helping me out!!


When does a dual of a compound proposition equal itself?

So I am studying computer science and right now I am stuck on a problem.  When does s∗ = s, where s is a compound proposition?  So far the only thing I can come up with is:  s* = s when the compound proposition is composed only of the same           propositions. (ex. p ∧ p = p ∨ p)  The book defines duality as:  The dual of a compound proposition that contains only the logical operators ∨, ∧, and ¬ is the compound proposition obtained by replacing each ∨ by ∧, each ∧ by ∨, each T by F, and each F by T. The dual of s is denoted by s∗. (Discrete Mathematics and its Applications, Rosen, 7e)  Any help would be great, this is a tricky one.


How can I start to learn web development?

I'm very interested in learning web development and have learned some basics regarding HTML and CSS a few years back from W3Schools, but I never learned how to develop websites that are up to today's standards, i.e. free-flowing sites without the use of tables to govern the design of the site.  What are some good resources that I can start with?


Install program on external HDD with Mac Book Pro

I'new in the Machintosh world. I'am running out of space on my Mac, so i try to install Epic Games and Fortnite on external HDD. Is it possible? How can I do?  Thanks


Store each animation frame as new object

Is it possible to store each animation frame as a new object? I searched quite a long time now on google and was wondering that I cannot find any information about this.  I just have a simple model with a simple pose animation and I'm looking for a way to get each frame stored as a new object, that I end up with maybe 100 objects "frame001", "frame002", "frame003", ...  I need this for a game engine that does not support bone animations, but I can fake such an animation by exporting this object (as a collada) and then setting only one of the "frame-objects" visible in this engine.    I tried to write a quick and dirty python script myself after some basic reading, but unfortunately the most important action (the conversion to a mesh) does not work:  import bpy  count=0  for x in range(bpy.data.scenes["Scene"].frame_start,bpy.data.scenes["Scene"].frame_end):     bpy.ops.object.duplicate_move()  bpy.ops.object.select_all(action='DESELECT')  obs = bpy.data.objects bpy.data.scenes["Scene"].frame_current=0         for ob in obs:     bpy.ops.object.select_all(action='DESELECT')     if ob.type == 'MESH' and ob.name.startswith("model"):         if count>0:             ob.select=True             bpy.ops.object.convert(target='MESH')             bpy.data.scenes["Scene"].frame_current+=1         count=count+1


Can I make my dough for dinner rolls ahead in bread maker and refrigerate overnight?

I want to make my dough for dinner rolls tonight in my bread maker and bake in the morning. Will this work? Also do I cut and shape before putting in the fridge for the night or do I do this in the morning before baking?  Thank you.


Protagonist finds coin from a parallel universe, lets it guide him via flipping heads/tails

This is a short story that I read several (5?) years ago. I don't believe it was new, but I don't remember how old it was, either. If I had to guess based on style, I would say that it was probably written sometime in the 80s or 90s.  The protagonist comes across an old coin that isn't from anywhere -- at least, not from anywhere that he or coin dealers or historians can identify. Somehow, he gets the idea that the coin is from another, parallel reality, and he decides that it would "want" to go home, if it could. He starts to travel, and whenever he comes to a decision about where to go next, he lets a coin toss (using that coin) decide the issue. The transition from one reality to another is gradual, not sudden like going through a portal, more like elements of reality being gradually replaced as he goes from one place to another.  Eventually, he does get to the place where the coin originated, at which point the plot (if I'm recalling correctly) devolves into a rescue-the-princess-from-the-clutches-of-the-evil-king/sorcerer/vizier scenario.  The parallel universe that the coin came from is full of deserts and has an "Arabian Nights" flavor. I think the protagonist meets a djinn/genie in the desert when he first gets to the right universe, but that could be something I'm mixing in from a different tale.  I'm drawing blanks on more specific details, but hopefully someone will recognize it from the above.


Symbolizing layer with graduated colors by date/time field?

I've got a layer of polygons where each has a date associated with it.  I want to color the polygons with graduated colors, but I want the colors to start with the newest polygons and fade to the oldest polygons.  So far I haven't been able to find a way to do this in ArcMap (<= 9.3.1) other than to create a new field and calculate some integer or float value based on the date.  Is it possible to use a date or time field directly?   The data is natively a date-time value There are far too many records to use any unique-value renderer Converting the date to a numerical field is an answer for a different question.


Who has a winning strategy in "knight" and why?

Perhaps, this game is already known, but I did not find anything about it, I call  it "knight".  The rules :   Player 1 chooses the starting square of a knight on a normal 8x8 - chessboard.  The players alternately move the knight to a square which was not already   visited. The player having no more move loses.  Which player has a winning strategy and why ?


What could be the effects of telling a small child "The bad man is going to come" as a threat to enforce good behavior?

My childhood best friend's family would tell their young daughter, maybe 5-7 years old things like "Im gonna call the bad man" or "The bad man's gonna get ya if you dont be good." I dont think they did this a whole lot but even if it was a rare thing for her parents, her older brother definitely took advantage of her fear on this "bad man" thing.   It definitely made her straighten up, but Im wondering if this discipline strategy, "fear of a thing" can have negative side effects.   Now that I'm writing this question, I guess Christians do this with the Devil / "You'll go to Hell if you dont live right", and children are probably more scared by this teaching than adults, if my childhood memory serves me correctly. So if the "bad man" fear disciplinary strategy is a bad thing for kids, might the religious version also have negative effects on them?


How remove Sakura R-727II range hood to clean inside?

I don't know how range hood is fixed under panel. By way, what do you call this fixation under panel?


upgrade Ubuntu 16.04 without losing data

I am using Ubuntu 14.04 LTS. I want to upgarde to Ubuntu 16.04 via the software updater application. I have lots of data in my laptop. Also I am having useful softwares related with my work.  Now I wish to upgrade my system without losing any data and software. Ca n I do it?. or else what is the procedure to upgrade Ubuntu without losing old data.


Do I need a transit Visa in Bangkok? Travelling from Singapore to Lucknow and transit at Bangkok

I'm travelling from Singapore to Lucknow (India) with transit at Bangkok. Here are the flight details:  Singapore - Bangkok : Thai Airways Bangkok - Lucknow : Thai Smile  Do I need a transit visa at Bangkok? I am getting mixed info that's why seeking more info if someone had travelled this route before.  I have travelled from Singapore to other Europe, India and Japan before and both legs were on Thai Airways and I didnt require a transit visa at BKK.  But in this instance, my second leg is on Thai Smile so not sure probably they follow the same rules.


There is an eject key on the upper right corner of my Magic Keyboard. Since I'm neither using the eject key directly nor any of the shortcuts associated to it, I would like to remap it to a symbol that I use more often. That is in my case the backslash.   How can I remap the eject key to backslash, preferably without using third-party software? I'm using High Sierra version 10.13.3 on a Macbook Pro 2017.


I want to ask the difference between "need to do" and "need to be doing." Here is an example"  We need to do this as soon as possible.  and:  We need to be doing this as soon as possible.


What is an easy to use web GIS stack to use for making fictional maps?

I am looking for a technology stack that would allow me to have some sort of OSM-driven custom map with as-easy-as-possible editing via a web frontend. I would require this for creating custom fictional maps for roleplaying games, so they wouldn't have any connection to the real world at all.  As for editing capabilities, I'm eyeing openstreetmap.org's current default web editor, iD. But to be honest, I have no idea what software I would need to make it all work together. I also have only limited knowledge when it comes to setting up virtual machines. If a ready-to-go appliance exists somewhere (or something that requires only trivial extra effort), I would be super grateful.  Edit/clarification: by "fictional map" I mean exactly that, a completely made-up map that very likely doesn't re-use a single node from Earth's actual map but instead is made-up from ground zero. I intend to use OSM for this, mostly because of the easily transferable data format, my (limited but still somewhat present) acquaintance with editing and the vast landscape of readily available mapping/rendering tools. I do intend to use most tags as they would be used on OSM, so editor presets are fine as they are for Earth's non-fictional map.  Edit/clarification #2: it should be web-based as we're physically scattered through-out the world. If we only passed an .osm file around, I fear that we could bump into very inconsistent vaguely different versions of said fictional map too easily.


I currently have a Windows 10 pen drive that isn't in use at the moment. I try to format the drive on disks, and the terminal using mkfs.vfat /dev/sdc1 and all I get is;  mkfs.fat 4.1 (2017-01-24) mkfs.vfat: unable to open /dev/sdc1: Read-only file system   Is there a way to format this to any file system? I'd like to use it for other things.


ok so I download Kali Linux to a usb stick plug it into my computer and I had to change my EFI to legacy I did everything went smoothly until I wanted to get back to windows 8 I restart my computer go into my boot options and windows boot is gone. So I don't have windows 8 someone plz help.


I know this question has been asked a lot, but none of the answers i have found have helped me.  I have a HP laptop that I have put Ubuntu 17.10 on and ever since the first boot it could not find any wifi or bluetooth adapters. I have tried to install Realtek drivers but it has not worked. My Wifi and Bluetooth adapters are built-in.  when I run lspci -nnk | grep -iA3 net the output is      02:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. Device [10ec:d723]     Subsystem: Hewlett-Packard Company Device [103c:8319]     Kernel modules: wl 03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 15)     Subsystem: Hewlett-Packard Company RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [103c:832c]     Kernel driver in use: r8169     Kernel modules: r8169   Thank you for your help.


PDFLatex, tikz, simple flows, ! Undefined control sequence.  \c@lor@to@ps

I wanted to draw a simple protocol flow using the tikz package. However, I got some errors and really don't know how to deal with them.  Here's the code in LaTeX:  \documentclass[12pt]{article} \usepackage{tikz} \usepackage{tkz-base,tkz-fct} \usepackage[utf8]{inputenc} \usepackage[english]{babel} \usepackage{graphicx} \usepackage{psfrag} \usepackage{amsmath} \usepackage{msc} \begin{document}  \begin{figure*}[!h] \center \resizebox{12cm}{!} { \begin{msc}{$IJS_{NK, dec/enc}$} \small \setlength{\instwidth}{1.7 cm} \setlength{\instdist}{2.3 cm} \setlength{\bottomfootdist}{0.2 cm} %\setlength{\instwidth}{2 cm} %\setlength{\instdist}{3.75 cm} \setlength{\envinstdist}{1.2 cm} \setlength{\topheaddist}{0.5 cm} \instfoot  \declinst{I}{\scriptsize new node}{$I$}  \declinst{R}{\scriptsize neighbour node}{$R$} \declinst{J1k-1}{\scriptsize intermediate nodes}{$J_{1:k-1}$} \declinst{Jk}{\scriptsize \:\: intermediate node}{$J_{k}$} \declinst{S}{\scriptsize Sink}{$S$}  % left to right messages \mess{$m_1 = \{n_I, I, R\}_{K_{DH}(I,S)}$}{I}{R} \nextlevel \mess{$\{n_R, m_1\}_{NK}$}{R}{J1k-1} \nextlevel \mess{$\{n_{J_{k-1}}, ..., n_{J_1}, n_R, m_1\}_{NK}$}{J1k-1}{Jk} \nextlevel \mess{$\{n_{J_k}, ..., n_{J_1}, n_R, m_1\}_{NK}$}{Jk}{S} \nextlevel  % right to left messages \nextlevel \mess{$\{n_{J_k}, ..., n_{J_1}, n_R, m_2\}_{NK}$}{S}{Jk} \nextlevel \mess{$\{n_{J_{k-1}}, ..., n_{J_1}, n_R, m_2\}_{NK}$}{Jk}{J1k-1} \nextlevel \mess{$\{n_R, m_2\}_{NK}$}{J1k-1}{R} \nextlevel \mess{$m_3$}{R}{I} %\nextlevel \end{msc} } \fbox{ \begin{minipage}{11.5 cm} $m_2 = \{pk(I), \{n_I, I, R, S\}_{K_{DH}(I,S)}\}_{K_{DH}(R,S)}$\\ $m_3 = \{K(R,I), \{n_I, I, R, S\}_{K_{DH}(I,S)} \}_{pk(I)}$ \end{minipage}  } \caption{$IJS_{NK, dec/enc}$: Proof by Induction.} \label{figure : IJS-NK-dec-enc Induction} \end{figure*}  \end{document}   I compile it in console using: pdflatex -synctex=1 -interaction=nonstopmode toc.tex.  My pdflatex version is:  pdfTeX 3.1415926-2.5-1.40.14 (TeX Live 2013/Debian) kpathsea version 6.1.1 Copyright 2013 Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX). There is NO warranty.  Redistribution of this software is covered by the terms of both the pdfTeX copyright and the Lesser GNU General Public License. For more information about these matters, see the file named COPYING and the pdfTeX source. Primary author of pdfTeX: Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX). Compiled with libpng 1.2.49; using libpng 1.2.50 Compiled with zlib 1.2.8; using zlib 1.2.8 Compiled with poppler version 0.24.5   However, I'm using it "inside" TeXMaker on Kubuntu 14.04.  pdflatex -synctex=1 -interaction=nonstopmode toc.tex > errors.txt:  Here's the *.log file: , and the errors .  xelatex toc.tex > xelatexerrors.txt:     latex toc.tex > latexerrors.txt:    Adding \usepackage[pdf]{pstricks} produced an empty pdf (I did pdflatex -synctex=1 -interaction=nonstopmode toc.tex > errors.txt), here're the erros:


Which of the following sets has the greatest cardinality?(Math subject GRE exam 0568 Q.61 )

How can I solve this question in only 2.5 minutes? It must be solved using deep insight and intuition, which I do not have. Could anyone help me, please?  Thanks!        Which of the following sets has the greatest cardinality?      (A) $\mathbb{R}$      (B) The set of all functions from $\mathbb{Z}$ to $\mathbb{Z}$      (C) The set of all functions from $\mathbb{R}$ to $\{0, 1\}$      (D) The set of all finite subsets of $\mathbb{R}$      (E) The set of all polynomials with coefficients in $\mathbb{R}$


Automatic text wrapping in ArcMap layout text element?

How can I word-wrap a text element on an ArcMap layout, when it contains a lot of text?   go into Layout mode choose > Insert > Text paste in a long text block eg    The text block now stretches across the screen, and there's no apparent way to change the width of the text block. Is there a way to set the text block to the desired width, and have ArcMap automatically enter line breaks?  (The way that, um, every other piece of software which handles text does...)  The workaround is to enter line breaks manually, which is great until you decide to change the width, font size, etc.


If the laws of physics work the same forward and backward in time, why does entropy grow in one direction?


The current item is automatically skipped if exited review page and re-open it

I am reviewing something when I accidentally press the site logo, which brings me to the front page of the site. Then I click the review button to the left of my info (avatar/rep/badge) and find that the number of the "number of review list items" is decreased by one, and the post I was reviewing no longer shows up in the rest of the queue. I think it has been automatically skipped when the review page was interrupted.  To reproduce:  Go to a site where you have access to a review, preferably FP. Note the number and click the title First Posts to obtain the first review item. Now don't do anything and click the site logo (or simply close the page). Re-navigate to the review page (//something.stackexchange.com/review) and you'll find the number decreased by one. If possible, you can finish the queue amd you won't find the "skipped" rev item.


What are good options to store, handle, catalog, search images?

I'm in the situation now that i have to bring some order in my folder structure. Up to now I had a single folder for each shoot, made up by the date and a short description for the shoot. For example: 20151015 Mountain shoot with fuffy  This quickly became a mess, and i need to begin with a new and better structure.  What would be a good folder structure that lets find pictures quickly depending on model, subject, year, stock/assignment/private life, etc.?  Is it Worth spending time keywording and cataloguing all pictures in lightroom for each shoot? In what way can this simplify searching the pictures? I would like to find a good workflow that covers folderstructure, download process, cataloguing, editing (seen as step, not going into the details.. I would rather like to see something like "open in lightroom, base editing, and then menu/edit in Photoshop" or something like that), searching for files.   I expect the answer to be sort of a tutorial for beginners.


Can short-term visitors do charity/volunteer work?

I remember a long time ago I was in some charity event my parents basically dragged me to, and I remember a girl there who said she's Canadian/from Canada and so it got me wondering:  1.If she's Canadian she's born in Canada and is probably not a U.S. citizen.  2.If she was in a charity event and wasn't a U.S. citizen, does that mean anyone can volunteer?  I ask because I think you need a work permit if you do any kind of paid work abroad when you're not a citizen, but volunteer/charity work isn't paid and the situation is obviously different.  Can non-citizens and/or only temporary visitors/residents do charity/volunteer work in the US?


I have two variables (which i'm getting from database):  $start = '07:14:10'; $end = '07:14:58';   I need to get the difference between these.  I think the answer could be 00:00:48.


Are you allowed to use numbers as table names in MySQL?

I'm thinking of having a program that dynamically creates new tables as the need arises. Can I have tables named with just numbers in MySQL?


I have a site on my webhotel I would like to run some scheduled tasks on. What methods of achieving this would you recommend?  What I’ve thought out so far is having a script included in the top of every page and then let this script check whether it’s time to run this job or not.  This is just a quick example of what I was thinking about:  if ($alreadyDone == 0 && time() > $timeToRunMaintainance) {    runTask();    $timeToRunMaintainance = time() + $interval; }    Anything else I should take into consideration or is there a better method than this?


The Data Science SE site requires syntax highlighting feature as the posts contain code from multiple languages/syntaxes including but not limited to Bash, Regex, Python, Julia, Java, R.  We collected a list of some posts which would benefit from this feature .  PS: I am one of the moderators of that site.


Is it bad to use two slots that are not adjacent to each other?

I've heard that you always want the same size of RAM (2x1GB sticks) but does their placement matter? I have four slots on my motherboard but does it matter if the sticks are not adjacent?  This particular question involves the


Cannot install and the code is not working: apt-get install virtualbox-guest-x11

I am using a full fresh installed Kali Linux rolling edition. And please be specific to me while explaining the matter because I am very new-be in the world of Linux. My host OS is Ubuntu 15.10.


Reputation not appearing on username flyout

The daily, weekly and month reputation on not appearing on either the StackOverflow or the Meta flyout that appears when hovering over the username.    Across the board everything is zero. I am seeing this in both Firefox and Chrome.


I have the following method which serialises an object to a HTML tag. I only want to do this though if the type isn't Anonymous.  private void MergeTypeDataToTag(object typeData) {     if (typeData != null)     {         Type elementType = typeData.GetType();          if (/* elementType != AnonymousType */)         {             _tag.Attributes.Add("class", elementType.Name);             }          // do some more stuff     } }   Can somebody show me how to achieve this?  Thanks


How do you center a div or anything else horizontally, so that on both sides the empty spaces are equal? And the div is exactly in the middle? No matter the size of the objects.  Take for example: the Stackoverflow site itself.  Except for the black header on the top of this site, everything is in the middle and the empty spaces on both sides are equal to each other.  I've searched for a long time, but I only encountered the wrong answers or vague answers.  Please help and thank you!


I don't know how to name what I am searching for... Force, Impact? It's easier to explain with an image for me. We have two GameObjects with colliders, A and B. They can move in any direction (top down game with 360° movement possibilities). First case (left): A go to the right at a speed of 2, B to the left at a speed of 1 and they collide. How to calculate that A take 1 damage (from the speed of B in its direction) and B take 2. Second case: A go to the right at speed of 2 and B to the right at speed of 1. A take 0 damage and B take 1.    I am using Collision2D which doesn't have "impulse" property. I have no idea how to calculate thing like this manually.


XeTeX and miriad "Missing character" messages in log file

I have a XeTeX source which compiles "nicely" into PDF except for many messages of the following kind  Missing character: There is no ೛ in font [Asana-Math]/ICU:script=math;language= DFLT;!   First of all, I would like to know is it possible to identify the line number with a character which is missing? My document is already big enough (~150 A4 PDF pages long) and contains a lot of math, so it is almost impossible to isolate such problems.  Secondly, I located one particular case when it happens and I'm unpleasantly surprised. The MWE is as follows  \documentclass{article}  \usepackage{unicode-math} %\setmathfont{[Asana-Math]}  \begin{document}     $\mathbfup{Z}^{+}$ \end{document}   Font used to typeset math does not matter, at least on my TeX Live 2013 installation the result is the same with both Latin Modern Math (default) and Asana Math fonts.  And surprise is that if you remove curly brackets over +, the corresponding Missing character message disappears from the log file. I always thought that ^{+} is semantically the same as ^+, since you can omit curly brackets when subscript or superscript is just 1 symbol long. But it feels like there is a difference.


Limit of the sequence which depends on another sequence

Can anyone solve this problem ?   I could not find any relation between terms of sequence.  So what is nth term of bn ? Can we evaluate an without finding bn ? Please help


toggle-password is not working if i clicked on the edit option

The first time toggle-password is working fine, but when I click on 'edit model' the model will open. After closing the model the toggle-password in the table is not working. I don't why it is not working. Can anyone please help me.  $(".toggle-password").click(function() {   $(this).toggleClass("fa-eye fa-eye-slash");   var input = $($(this).attr("toggle"));   if (input.attr("type") == "password") {     alert('test');     input.attr("type", "text");   } else {     input.attr("type", "password");   } });      <?php     if($auth_details['auth_key'] != "")     {       $r_id = $auth_details['id'];       $ak = $auth_details['auth_key'];       echo "

                 <input class='form-control' id='auth_keyt_".$r_id."' value='".$ak."' name='auth_keyt_".$r_id."' type='password' required autocomplete='off' style='border:none;'/>

";     }     else      {       echo '';     }   ?>


Getting "TypeError: string indices must be integers" in python

I tried imitating my code in simple steps on python prompt:  >>> path="D:/workspace/a/b\\c\\d.txt" >>> path[0,18]   But it gives me following error:  TypeError: string indices must be integers   I wanted to retrieve only directory as path. That is, I want to strip away the file name: D:/workspace/a/b\\c  Why I am getting this error?


Does anybody know the easiest way to prevent a subfigure from going to the next page? I have 3 subfigures, 1 or 2 of which would easily fit on the previous page, but because it is in one figure, it puts all three figures on the next page.   My code is:  \begin{figure}[H] \begin{center} \subfigure[Results on MNIST fully connected]{ \includegraphics[scale=0.48]{result4_mnist_fc_s2gd.png} } \subfigure[Results on MNIST ConvNet]{ \includegraphics[scale=0.48]{result5_mnist_conv_s2gd.png} } \subfigure[Results on CIFAR-10 ConvNet]{ \includegraphics[scale=0.48]{result6_cifar10_s2gd.png} } \end{center} \caption{Results for S2GD methods} \label{fig:NN_example} \end{figure}   Thanks!


How do I upgrade 19.04 to 19.10 when packages won't update?

I can't seem to get these packages to upgrade which is preventing me from doing a release upgrade. How can I get around this?  apport/eoan-security,eoan-security 2.20.11-0ubuntu8.8 all [upgradable from: 2.20.10-0ubuntu27.3] dbconfig-mysql/eoan,eoan 2.0.11ubuntu2 all [upgradable from: 2.0.11] dovecot-lmtpd/eoan 1:2.3.4.1-5ubuntu3 amd64 [upgradable from: 1:2.3.4.1-1ubuntu2.4] dovecot-mysql/eoan 1:2.3.4.1-5ubuntu3 amd64 [upgradable from: 1:2.3.4.1-1ubuntu2.4] libbind9-161/eoan-security 1:9.11.5.P4+dfsg-5.1ubuntu2.1 amd64 [upgradable from: 1:9.11.5.P1+dfsg-1ubuntu2.6] libdns1104/eoan-security 1:9.11.5.P4+dfsg-5.1ubuntu2.1 amd64 [upgradable from: 1:9.11.5.P1+dfsg-1ubuntu2.6] libgnutls30/eoan-security 3.6.9-5ubuntu1.1 amd64 [upgradable from: 3.6.5-2ubuntu1.1] libirs161/eoan-security 1:9.11.5.P4+dfsg-5.1ubuntu2.1 amd64 [upgradable from: 1:9.11.5.P1+dfsg-1ubuntu2.6] libisc1100/eoan-security 1:9.11.5.P4+dfsg-5.1ubuntu2.1 amd64 [upgradable from: 1:9.11.5.P1+dfsg-1ubuntu2.6] libisccc161/eoan-security 1:9.11.5.P4+dfsg-5.1ubuntu2.1 amd64 [upgradable from: 1:9.11.5.P1+dfsg-1ubuntu2.6] libisccfg163/eoan-security 1:9.11.5.P4+dfsg-5.1ubuntu2.1 amd64 [upgradable from: 1:9.11.5.P1+dfsg-1ubuntu2.6] libnss-systemd/eoan-security 242-7ubuntu3.6 amd64 [upgradable from: 240-6ubuntu5.8] libpam-systemd/eoan-security 242-7ubuntu3.6 amd64 [upgradable from: 240-6ubuntu5.8] librados2/eoan-security 14.2.4-0ubuntu0.19.10.2 amd64 [upgradable from: 13.2.6-0ubuntu0.19.04.4] libsystemd0/eoan-security 242-7ubuntu3.6 amd64 [upgradable from: 240-6ubuntu5.8] libudev1/eoan-security 242-7ubuntu3.6 amd64 [upgradable from: 240-6ubuntu5.8] python3-apport/eoan-security,eoan-security 2.20.11-0ubuntu8.8 all [upgradable from: 2.20.10-0ubuntu27.3] python3-apt/eoan-security 1.9.0ubuntu1.3 amd64 [upgradable from: 1.8.5~ubuntu0.3] python3-venv/eoan 3.7.5-1 amd64 [upgradable from: 3.7.3-1] systemd-sysv/eoan-security 242-7ubuntu3.6 amd64 [upgradable from: 240-6ubuntu5.8] systemd/eoan-security 242-7ubuntu3.6 amd64 [upgradable from: 240-6ubuntu5.8] udev/eoan-security 242-7ubuntu3.6 amd64 [upgradable from: 240-6ubuntu5.8]


I removed admin rights for the original admin account, in order to set up a new account with clear history. (Not 100% that was needed, I am still getting to grips with linux / Ubuntu 12.04 and I read somewhere that its not wise to use original account day to day, which I initially did.)  However, I didn't activate the password for the new account before applying changes.  Here's what I did:   set up new account (no password) Added admin Rights Removed admin right from original No admin access    It now seems as though I have no sudo /admin access. Since I need the 'unset' password of the inactive account, which is the only one with admin rights.


How do I install the  on Mac with MacTeX 2013 and Windows with TeX Live 2013? I am using pdflatex so   does not solve my problem.


Do mankind and manmade activities/constructions have any effect on the rotation of the Earth?

We walk or ride on our vehicles to our destinations daily. Does our movement have any effect on the rotation of the earth according to Newton's law? What will be the effect if we move all the peoples along with their vehicles at their maximum velocity in one line in one direction along the equator? How much effect will it make?


How to change permissions on vfat partition?

Is it possible to change the permissions on a vfat partition in Ubuntu?  Nothing has worked.. tried entry in /etc/fstab, tried to chown, the only way I can grant access to this location is by giving the application ownership and that is bad.


Finding $\lim_{n \to \infty} \int_1^a \frac{n}{1+x^n} \, dx$

I'm trying to find $$ \lim_{n \to \infty}   \int_1^a \dfrac{n}{1+x^n} \, dx  ,$$ where parameter $a>1$. The limit appears to be $\ln 2$ regardless of the value of $a$. Some trick is probably needed here, but i don't see it.


How to find a good topic for a PhD research proposal?

In many countries an application for a PhD position includes a written research proposal, so my questions is what are some advises/strategies to come up with a good topic/idea for a PhD research proposal and how can one assess the quality/fruitfulness of an idea? As an undergraduate student one just doesn't have the experience to foresee which ideas might have promising research results and which probably won't have. (And I doubt that potential supervisors have the time to comment on every idea of every potential applicant in cases where it is possible to establish some kind of contact before the actual application.)


Just want to understand, whether is there any vulnerability in this code, and any possibilities of altering the sql syntax by unsafe POST variable. please can someone advise, also please share an example of secured version of this code if this is has vulnerability and open to sql injections. Thanks.         <?php    $database = '     (DESCRIPTION =     (ADDRESS_LIST =    (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))    )    (CONNECT_DATA =    (SERVICE_NAME = pdsales1)    )    )';      $db = new PDO('oci:dbname='.$database, 'hr', 'hr');      $sth = $db->prepare('SELECT EMPLOYEE_ID,FIRST_NAME FROM EMPLOYEES where department_id=:department_id');     $sth->bindParam(':department_id', $department_id);     //$department_id=[$_POST['department_id'];     $department_id=20;     $sth->execute();     $rows = array();     while($row = $sth->fetch(PDO::FETCH_OBJ)) {       $rows[] = $row;     //echo $row->FIRST_NAME."\n";       }    $json_data=json_encode($rows);     //echo $json_data;    ?>