Duplicate meta title and description displayed in Google Webmaster Tools

In Google Webmaster Tools under Search Appearance --> HTML Improvements it's showing:  Duplicate Meta Titles - 166 Duplicate Meta Descriptions - 275  For example:  Duplicate title tags  Offer prices on Guitars, Pianos, Drums, Saxophones & Violins - Offers in Bangalore, Chennai, Hyderab     /musical-instruments-2      /musical-instruments-2?manufactureid=103&pagesize=40      /musical-instruments-2?manufactureid=103&pagesize=800&orderby=15      /musical-instruments-2?manufactureid=56&pagesize=320      /musical-instruments-2?manufactureid=60&pagesize=160      /musical-instruments-2?manufactureid=86&pagesize=400      /musical-instruments-2?pagesize=12&manufactureid=76&orderby=10      /musical-instruments-2?pagesize=240      /musical-instruments-2?pagesize=600      /musical-instruments-2?pagesize=80&manufactureid=104   Duplicate meta descriptions  Springwel Mattress Bangalore with 5 Guaranteed Benefits | Best Price, Quick Door Step Service, Free     /springwel?orderby=11      /springwel?orderby=15      /springwel?pagesize=160      /springwel?pagesize=350      /springwel?pagesize=40   Why is it showing this and how can I remove these duplicate titles and descriptions?


Which form is correct in expressions like this: 1) team's size or 2) team size?  And a similar one: 1) actual period length or 2) actual period's length.  Is there any rule?


Does $\sum\limits_{k=1}^∞\frac1{k^{\ln k}}$ converge or diverge?

$$\sum_{k=1}^{\infty} \frac{1}{k^{\ln k}}.$$  I have some problems with this sum, I have tried most of the common methods, such as the ratio/root test, integral test, etc. I do believe it looks like a problem easily solvable by a direct comparison with some p-series, however, I do not know how to formulate the inequality.   I did try using the common fact that $\ln(x) \ll x^p$ for large $x$ but that of course only bounds it from below with a convergent series saying nothing about ours. Also I tried rewriting the 'summand' as $e^{\ln(k^{\ln k})}=e^{\ln k \cdot \ln k}$ but this did not really yield anything.   Any answer or hint would be greatly appreciated.


Absolute vs relative links for search engine crawlers and SEO

Our site's navigation links are currently in relative form:     The SEO company I mentioned in my  recommends we change them to absolute links:     This is to "ensure search engines get the correct and working URL for the pages". Is this really something that should be taken into account or is this another case of extra work with no added benefit?


Is the Moderately Armored Feat really the only way for my dwarf to get shield proficiency without multiclassing?

I really enjoy working out rather unusual character builds, or taking a subpar character concept and try to make it work using min/maxing, point buy and having every level from one to twenty planned out before even starting the adventure (ability increases, feats, equipment, etc). My latest project is a wizard that is as tanky as possible (tanky meaning having high AC in this case).   To achieve this, my wizard would be a mountain dwarf (starting with light and medium armor proficiency), and have 14 Strength. Depending on how the campaign goes, around the time I'm getting close to having enough gold to buy a suit of plate armor I would forego an ability score increase in favour of the "Heavily Armored" feat (also giving me +1 Strength, raising that ability to the score needed to wear plate armor without getting a movement penalty.  Now, I would have an AC of 18, which is quite high for a wizard. But, as stated, my goal is for my character's AC to be as high as possible. Adding a shield to my character's equipment would seem like a cheap way to get an extra +2 AC for an impressive total of 20. But this is where I finally get close to my question.  Shields have a separate proficiency in 5E and wearing armor you are not proficient with not only imposes disadvantage on any ability check, saving throw, ar attack roll that involves Strength or Dexterity, but also makes it impossible to cast spells. Not being able to cast spells would make my wizard kind of pointless so in order to make this work I would somehow have to get proficiency with shields.  At this point there are two ways to get shield proficiency in 5E: multiclassing one level in a class that has shield proficiency or taking the "Moderately Armored" feat. Multiclassing isn't really an option for me since it would leave me unable to get the high level Wizard features. So I would have to take the feat just to get shield proficiency. Since I'm already proficient with medium armor this seems like a complete waste of a feat to me. If that is as it is intended to work I wouldn't take the feat.  So my question is: Is the Moderately Armored feat really the only way to get shield proficiency without multiclassing?  Because it sort of seems like an oversight. Now, the developers can't reasonably be expected to take in to account people like me creating stupidly specific situations like this: a heavily armored dwarf wizard who uses a shield (my character would still be able to perform the somatic components for spells even wielding a shield since he would not wield a weapon). For the vast majority of character builds this would never be an issue, but I really think shield proficiency should also be included in the "Heavily Armored" feat.  In my other wacky character concepts I have found that sticking to the rulebooks generally works out just fine. My DM also sticks to RAW and doesn't use any homebrew rules. Normally I'm all for sticking to RAW but this just seems kind of silly. According to the rulebook, my wizard could hold a chair in his left hand and would still be able to cast spells, but when he's holding a shield this is suddenly no longer possible.


I downloaded 13.04 which took me a couple of hours.  I can't tell which file to select to begin the installation.  Please let me know what to do next.


Why do objects with different masses fall at the same rate?

Possible Duplicate:          Today we were in our Literature class talking about the Renaissance and the Enlightement and our teacher also said that scientific experiments were being conducted, and she gave as an example the experiment in which they dropped objects with different mass from a tower to see which object would land first. She then said that she herself didn't know the outcome and since I'm known in my class as the #1, they asked me and I said that they landed at the same time (to my shock many classmates even disagreed with me about this fact). The teacher asked me to explain why and we haven't had anything about inertia in our physics class, so I was forced to use my own self-thought knowledge of physics: I said gravity does pull harder on heavier objects, but heavier objects have more resistance to move, in other words, they have more inertia. The entire class except for the teacher disagreed with me even though they usually don't. One fairly annoying kid asked me to explain why a feather falls way slower than a bowling ball, and I explained why and I also made the claim that in a vacuum they would fall at the same rate. Was I right or my class? Of course I know my explanation is lacking, but it has truth to it, right?


How can we count/list all files opened by a specific program/COMMAND?

We can list only files opened by a specific PID as lsof -p 1000 lsof -p 1000 | wc -l  How can we list/count the files opened by a specific program/COMMAND (e.g., java)? And so much better, if we can group the number of open files for each program. I want to inspect which programs have high numbers of opened files. I want something like lsof -c "java" # -c is an imaginary argument similar to -p for process  I use Ubuntu 20.04.


How I can connect multiple Postgres Database in a single SQL query?

This is Metabase Related Question. I know how to cross join in PostgreSQL.  I have multiple staging databases to store raw data in postgreSQL. All databases are in same host.  Now I want to join multiple databases for analysis in Metabase. I saw before create a raw query first I need to select database.  Is there any way around for this ?


Question regarding an Op-Amp substitution

This schematic has a LM107 op-amp at its heart. It seems that it is now discontinued. Will a uA741 op-amp be a good substitute? If not, why not? What would be a good substitute?  Thanks.


What is the difference between reboot , init 6 and shutdown -r now?

I just want to know difference between in     reboot  init 6 shutdown -r now   and which is the safest and the best?


Extreme point of unit balls, over $\mathbb C$

I've been trying to determine what are the extreme point of the unit balls of $\ell^1$ and $\mathcal{C}[0,1]$.  I think that I cracked the real case (I got for $\ell^1$: $\{e_n\}_{n\in \mathbb N}\bigcup\{−e_n\}_{n \in \mathbb N}$, and for $\mathcal{C}[0,1]$ the constant functions $f=1$ and $f=−1$).  I had a little trouble figuring out what should be the answer in case the field is $\mathbb{C}$. I think it should be (for $\ell^1$) all the $\{e_n\}_{n\in \mathbb N}\bigcup\{−e_n\}_{n \in \mathbb N}\bigcup\{ie_n\}_{n\in \mathbb N}\bigcup\{−ie_n\}_{n \in \mathbb N}$, and (for $\mathcal{C}[0,1]$) the functions $f=1,f=−1,f=i,f=−i$. But I can also see it go to (for $\ell^1$) all the $\{ae_n:|a|=1\}$, and (for $\mathcal{C}[0,1]$ all the constant functions $f=a$ with $|a|=1$.  I would like some guidness if possible. Knowing the right answer could help, as well as the intuition behind and maybe some tips on how to get there. Thanks!!


Python Multiplication with 2 decimal number as product result

Is there a way to this simple equation? I'm getting as a product result : 858.2999999999999682365192655  the simple equation is this:  from decimal import Decimal   x = Decimal(57220) * Decimal(0.03)  y = x / Decimal(2)  print(y)   The expected answer should be 858.30 Also tried this but it rounds this off to 858.00     x = Decimal(57220) * Decimal(0.03)   y = x / Decimal(2)   z = round(y, 2)   print(z)   I'm really sorry I'm just a beginner here in python  BTW I'm using 3.6 version of python  Edited : I'm sorry it should be 57220 :(


We have domain.com and want to test a new site template on beta.domain.com. What is the correct way to run a beta test without affecting SEO of the main domain.com? In the topic  I found 2 recommendations:  Putting a robots.txt with noindex to our beta.domain.com Canonicalizing beta.domain.com to domain.com - Why? In any case we already have the noindex flag...  Does it still actual in 2020? Do you have any other recommendations? By the way, do we need to register beta.domain.com in Google Webmasters Tools?


Why is the coefficient of kinetic friction greater than the coefficient of static friction?

I am a physics major taking freshman year physics courses. We did a lab experiment where we were given three objects and inclined plane, and we were asked to find the coefficients of kinetic and static friction for each object. The coefficient we found for static friction was greater than kinetic friction in each object. It was greater by about 0.05 in each object (e.g. mu_s = .22, mu_k = .29).  Our method to find the coefficient of kinetic friction was to measure the acceleration down the ramp using a vernier sensor, then solve using the mass and the angle, which was arbitrarily chosen to be 26.8 degrees.  Our method to find the coefficient static friction is not very precise. We used a pulley system to elevate the ramp until the object was just barely sliding, and we measured the incline at that point. Therefore, our coefficient of static friction is really only a best estimate.   As the saying goes, "it's a poor workman who blames his tools,"  or in this case his experimental method. But there is no special condition to make this situation predictable, and I can't find another explanation other than our "best estimate" method simply isn't accurate enough. Or is the 0.05 a negligible amount?  Any ideas?  The current draft of my lab report is posted here.


Prove if $\lim_{x\to +\infty}(f(x)+f'(x))=0$ then $\lim_{x\to +\infty} f(x)=0$

Let $f$ be a real function  continuously differentiable at $\Bbb R$ such that $$\lim_{x\to +\infty}(f(x)+f'(x))=0$$ prove that  $$\lim_{x\to +\infty} f(x)=0$$ I tried tu use exponential function knowing that  $$\frac{d}{dx}f(x)e^x=(f(x)+f'(x))e^x$$ but I got nothing. thanks in advance for an answer or un idea


elliptic curve multiplication with negative factor

I'm learning the multiplication operation on EC. From most material I can found, the multiplication $nP$ is just:  $$nP=P+P+\cdots +P+P$$ For negative factor, i.e. $(-n)P$, by above definition and the definition of $-P$, we can write $(-n)P$ as:  $$(-n)P = (-P) + (-P) + \cdots (-P)$$  My question is: is it possible to expression $(-n)P$ as $mP$ where $m>0$ under reasonable assumption? For example, we can assume the knowledge of the group order.  I'm asking so because $nP$ on EC is analogous to exponentiation in group $\mathbb{G}$ with order $p$. And in the latter case we have  $g^{-n} \equiv g ^{k\phi(q)-n}\pmod q, \forall k\in \mathbb{Z}$ by Fermat's little. So I'm wondering if there is a similar result for EC.


I came across this question on Stack Overflow: , which has one comment by user . I  hovered over his name link and saw that he has just the 1 rep.  In the , Comment Everywhere privileges require 50 rep. Soerium is not OP of question.


Is it true that if two groups have same number of elements of order n, then they are isomorphic?

I know that if two groups are isomorphic, they have same number of elements of order n. But will the converse holds? I think it won't  as there are many group characteristicss like abelian or cyclic will also matter. But I can't come up with example.


How to dynamically insert a value from a php generated result list in the search bar using jquery?

It's difficult to explain but i'll do my best. 1 - I want to build a search bar that, on the jquery event keypress, searches in my database what the user has digited.  2- Then i want to fill a div with the results found. 3 - then i want to click or tap the value and see the value tapped or click filling the search bar.  No problems with step 1 and 2, because using jquery $.post() method all works fine but i cannot complete step 3, because i generate an html in my php file that, by the callback function of $.post method, fill the div. The problem is that jquery seems not able to catch the class i inserted into php generated file. So my question is: what's the proper way to achieve my goal? I hope i explained well ;)


I have an xml file of this structure  <?xml version="1.0" encoding="iso-8859-1"?> <my_events>                         <event id="e20111129215359">                             <title>the title</title>                             <channel id="1">                                 <name>A name</name>                                 <onclick></onclick>                             </channel>                             <event_site>                                 <name/>                                 <url/>                             </event_site>                             <start_date>Thu Mar 08 2012</start_date>                             <start_time>11:00 AM</start_time>                             <end_date>null</end_date>                             <end_time>null</end_time>                             <notes>Notes for the event</notes>                         </event>  </my_events>   To delete an event, I have this php function.  <?php  include_once("phpshared.php");  function delete_event( $nodeid ) {      $nodes = new SimpleXMLElement('my_events.xml', LIBXML_NOCDATA, true);      $node = $nodes->xpath("/my_events/event[@id='$nodeid']");      $node->parentNode->removeChild($node);      $formatted = formatXmlString($nodes->asXML());     $file = fopen ('my_events.xml', "w");      fwrite($file, $formatted);      fclose ($file);    }  echo delete_event(trim($_REQUEST['nodeid']));  ?>   That doesn't delete the node.  Is there a different way to do this?


Powershell Get-ChildItem Include\Exclude - simple script not working properly

Im trying to run the following code as a powershell script,but I cant get it to work. 1st,the following works with one -Include item but I cant seem to get it to work with multiple ones. 2nd, the -Exclude perimeter doesn't seem to work. I still get files from the C:\Windows and C:\Program Files directorys .  $Include = "*.zip","*.rar","*.tar","*.7zip" $exclude = "C:\Windows","C:\Program Files" Get-ChildItem "C:\" -Include $Include -Exclude $Exclude -Recurse -Force -ErrorAction silentlycontinue | Select-Object -ExpandProperty FullName   Note: The purpose of this script is to find all compressed files on the system. I know this is probably really simple but I just cant seem to get it to work.


How to use trigger design pattern: ERROR Constructor not defined: [CaseTriggerHandler].()

I am trying to follow the best practice design patterns for triggers but get the error Constructor not defined: [CaseTriggerHandler].(). What am I missing?  Trigger  trigger CaseTrigger on Case (before insert, before update, before delete, after insert, after update, after delete, after undelete) {      CaseTriggerHandler handler = new CaseTriggerHandler();      //Before Insert     if(Trigger.isInsert && Trigger.isBefore){         handler.OnBeforeInsert(Trigger.new);     }     //After Insert     else if(Trigger.isInsert && Trigger.isAfter){         handler.OnAfterInsert(Trigger.new);     }     //Before Update     else if(Trigger.isUpdate && Trigger.isBefore){         handler.OnBeforeUpdate(Trigger.old, Trigger.new, Trigger.newMap);     }     //After Update     else if(Trigger.isUpdate && Trigger.isAfter){         handler.OnAfterUpdate(Trigger.old, Trigger.new, Trigger.newMap);     }     //Before Delete     else if(Trigger.isDelete && Trigger.isBefore){         handler.OnBeforeDelete(Trigger.old, Trigger.oldMap);     }     //After Delete     else if(Trigger.isDelete && Trigger.isAfter){         handler.OnAfterDelete(Trigger.old, Trigger.oldMap);     }     //After Undelete     else if(Trigger.isUnDelete){         handler.OnUndelete(Trigger.new);     } }   Handler      public with sharing class CaseTriggerHandler {      private boolean isExecuting = false;      public CaseTriggerHandler(boolean isExecuting){         this.isExecuting = isExecuting;     }      public void OnBeforeInsert(List<Case> newCases){         //EXECUTE BEFORE INSERT LOGIC     }      public void OnAfterInsert(List<Case> newCases){         //EXECUTE AFTER INSERT LOGIC     }      public void OnBeforeUpdate(List<Case> oldCases, List<Case> updatedCases, Map<Id, Case> CaseMap){         //BEFORE UPDATE LOGIC     }      public void OnAfterUpdate(List<Case> oldCases, List<Case> updatedCases, Map<Id, Case> CaseMap){         //AFTER UPDATE LOGIC     }      public void OnBeforeDelete(List<Case> CasesToDelete, Map<Id, Case> CaseMap){         //BEFORE DELETE LOGIC     }      public void OnAfterDelete(List<Case> deletedCases, Map<Id, Case> CaseMap){         //AFTER DELETE LOGIC     }      public void OnUndelete(List<Case> restoredCases){         //AFTER UNDELETE LOGIC     }      public boolean IsTriggerContext{         get{ return isExecuting;}     } }


how to add the reference to the content?

Today ,I use the \tableofcontentsto yield a content ,however ,it lacks of the reference .  My trial        \documentclass{ctexart }       \begin{document  }         \addcontentsline{ toc }{ section }{Reference }         \tableofcontents       \end{ document }   Fortunately ,the reference appear to the first line ,while I need it appear on the last line.  so I wonder how to revise.thanks .


How to call a python script in backend in flask

I'm trying to call a complicated python script in a flask app, but not entirely sure on how to do it right now. If it was simple I would just copy and paste the script with a router in flask, but that would get too messy. So far I have this for my main.py. I want to call a script temp.py.  from flask import Flask, render_template, request app = Flask(__name__)  @app.route('/') def base():     return render_template("base.html")   @app.route('/temp', methods=['GET', 'POST']) def temp():   if __name__ == "__main__":     app.run(debug=True)


Is light shed from a spell blocked by total (transparent) cover?

Many spells shed light as one of their effects, such as the Sunbeam spell, which says:     For the Duration, a mote of brilliant radiance shines in your hand. It sheds bright light in a 30-foot radius and dim light for an additional 30 feet. The light is sunlight.   We know that spell effects are blocked by total cover (PHB, p.204):     A spell’s effect expands in straight lines from the point of origin. If no unblocked straight line extends from the point of origin to a location within the area of effect, that location isn’t included in the spell’s area. To block one of these imaginary lines, an obstruction must provide total cover.   And that transparent obstacles still qualify as total cover (citation needed, but I'm pretty sure about this one).  Thus it seems to be the case that a glass window (or other transparent obstruction) can block magical light. However, this seems odd when you consider non-magical light can obviously pass through it fine.   So: can light from a spell like Sunbeam pass through a window, or not?


Is $\sum_{n=1}^\infty \frac{\sin(2n)}{1+\cos^4(n)}$ convergent?

As I was just checking this 'child prodigy' out on Youtube, I stumbled upon  video, in which Glenn Beck asks the kid to do the following proof:    Further on, the kid starts sketching a proof (without a shadow of a doubt regarding the accuracy of his solution ) including the Integral Test. I don't know much about improper integrals since I just finished highschool, but this integral approach seemed, intuitively, pretty inaccurate to me since this is not a strictly decreasing function. Then I found this out from Wikipedia !   Furthermore, the blunt assessment that the series are convergent seems dubious as well..Upon a few computations of my own(mostly partial sums) , I tend to believe that the series are, in fact, divergent .  Can anyone suggest a rigurous take on this problem (easy as it may seem to some amongst you) ?


Volume 4 of Charles Burney,  (1776) contains this sentence:     And while it [Rousseau's Lettre sur la Musique Françoise] was read by all the rest of Europe as an excellent piece of musical criticism, full of new ideas and views concerning dramatic Music, it was held in execration by the adherents to the ancient style of opera Music, and has been lately called "a wretched performance, dictated by spleen, bad taste, want of judgment, and inconsistence," by a writer [M. de la Borde] who, on some occasions, seems to know better, and to have ideas of good Music, more worthy of a master of harmony and the present state of the art in every part of Europe.   My questions are: How, when and where did the phrase 'state of the art' originate?


Beginner logic: negated "&" without using disjunction

I'm working through the exercise in Logic by Paul Tomassi and have got myself stuck on the following problem.  Prove the validity of the following sequent.  $ (P\land Q)\to \sim R: R\to(P\to \sim Q) $  So far, the book has introduced:   conjunctions and the rules for & insertion and removal conditionals and rules modus ponens, modus tollens and conditional proof insertion biconditionals and their insertion and extraction negation - modus tollens and double negative insertion and extraction.   The book has not introduced disjunction yet, so the challenge is to prove the validity of the sequent without recourse to the rules around disjunction. The book suggests it should be easy using modus tollens and the double negative rule. The author's note suggests the proof should require 11 lines.  Every time I approach it I go down the following line, which I think is a dead end.  {1}  1. $\qquad (P \land Q)\to \sim R \qquad \qquad $  premise  {1}  2. $\quad \ \ \sim \sim R \to \sim (P\land Q) \quad \ \ \ \ \ \ 1,MT$  {1}  3.  $\quad \ \ \ R \to \sim (P\land Q) \quad \qquad \quad  $ 2, DNE  And this is where I get stuck. The rest would be trivial if I could show that   $\sim (P\land Q) : (P \to \sim Q)$  While that's intuitively obvious, I don't see how I can get there without using DeMorgan's Laws and disjunctive syllogism.  Am I missing something incredibly obvious?  Thanks,  Billy.


Retrieving record IDs after inserting a List of objects

I Have used Enforce Security With the stripInaccessible Method to Create Record in Account Object List<Account> newAccounts = new List<Account>(); Account a = new Account(Name='Acme Corporation'); Account b = new Account(Name='Blaze Comics'); newAccounts.add(a); newAccounts.add(b);   SObjectAccessDecision securityDecision = Security.stripInaccessible(                                          AccessType.CREATABLE, newAccounts); insert securityDecision.getRecords();  Now I want to get the Record Id of each record inserted in Account Object. Can you help me on this.


A little backstory here. Someone tried to school me on the internet when I made a comment about how something was a liquid. My direct quote was: "Cats are a liquid" Now immediately someone replied with the following language lesson:  I get the point he makes with Air, Rice or Water, but if you want to specify an aggregation state of a substance, or in this particular case a creature, wouldn't that be correct usage?


Can a blocking creature tap for its ability while blocking?

I've declared my attack, and my opponent declares their blocker. I then use an instant that boosts and gives first strike to my attacking creature, then in the middle of combat they tap the creature to activate its ability. Can they do this?


I found out that on the MCPE 1.2 update, Mojang added components to commands. But when I try to enter  /give @p diamond_sword 1 0 { display: {     Name: "Sword of Ethania",     Lore: [         "Legendary",         "The Guardian Sword that defends Ethania"     ] }, ench: [     {         id: 16,         lvl: 1     },     {         id: 17,         lvl: 1     },     {         id: 18,         lvl: 1     },     {         id: 19,         lvl: 1     },     {         id: 20,         lvl: 1     },     {         id: 32,         lvl: 1     },     {         id: 34,         lvl: 1     } ], HideFlags: 1, Unbreakable: 1 }   then I get this error message:  *Line 1 Column 2 Missing '}' or object member name   Please help me debug, I have found nothing wrong in the command. Minimized Version:  /give @p diamond_sword 1 0 {display:{Name:"Sword of Ethania",Lore:["Legendary","The Guardian Sword that defends Ethania"]},ench:[{id:16,lvl:1},{id:17,lvl:1},{id:18,lvl:1},{id:19,lvl:1},{id:20,lvl:1},{id:32,lvl:1},{id:34,lvl:1}],HideFlags:1}


How to prove that $\lim_{n\rightarrow\infty}\left[\frac{(n+1)^{n+1}}{n^n}-\frac{n^n}{(n-1)^{n-1}}\right] = e$

I learnt on  that $$\lim_{n\rightarrow\infty}\left[\frac{(n+1)^{n+1}}{n^n}-\frac{n^n}{(n-1)^{n-1}}\right] = e$$ How should I prove this? Attempt: $$\begin{align} \lim_{n\rightarrow\infty}\left[\frac{(n+1)^{n+1}}{n^n}-\frac{n^n}{(n-1)^{n-1}}\right] &= \lim_{n\rightarrow\infty}\left[\left(1+\frac{1}{n}\right)^n(n+1)-\left(1+\frac{1}{n-1}\right)^n(n-1)\right]\\ &=\lim_{n\rightarrow\infty}e(n+1)-e(n-1)\\ &= 2e \end{align}$$ Why did I get a $2e$? Where did I do wrong? Isn't $$\lim_{n\rightarrow\infty}\left(1+\frac{1}{n-1}\right)^n=e?$$


Is the $\sum\sin(n)/n$ convergent or divergent?

Possible Duplicate:          So, in my calculus class (one I'm teaching, not taking), the sum $\sum_{n=1}^\infty \frac{\sin(n)}{n}$ has come up a few times.  Unfortunately, as someone not exactly an expert in the convergence of sums, it seems to resist the few techniques I know.  Certain none of the usual first year calculus tricks (integral test, alternating series test, ratio test, etc.) work, and the only more tricky technique, partial summation, I can think of doesn't seem to work either (one would need that $\sum_{n=1}^N\sin(n)$ is bounded, which I believe is false).  It seems like it should converge, since it switches sign quite often, but on the other hand, the harmonic series can mess with your intuition, so I don't have much trust in that.  So, I ask to you:     Does this series converge?


According to "" (pg. 44), you can pipe only STDERR using the |& redirection symbols.  I've written a pretty simple script to test this:  #!/bin/bash echo "Normal Text." echo "Error Text." >&2   I run this script like this:  ./script.sh |& sed 's:^:\t:'   Presumably, only the lines printed to STDERR will be indented. However, it doesn't actually work like this, as I see:      Normal Text.     Error Text.    What am I doing wrong here?


On $\lfloor\sqrt n \rfloor+ \sum_{j=1}^n \lfloor n/j\rfloor$

How do we prove that $\Big[\sqrt n \Big]+ \sum_{j=1}^n \bigg[ \dfrac nj\bigg]$ is an even integer for all $ n \in \mathbb N$ ? (where  $\Big[ \space \Big]$ denotes the "greatest integer" function)


I'm trying to grab a word(s) between the word "in" and "with" inside of a string. The problem is that I have another instance of "with", it will extend the wildcard.  Here is an example:  $item   = 'This is a car in red with new tires and with a radio'; $pattern =  = '/in (.*) with/i'; preg_match($pattern, $item, $matches);   Returns:  array(2) {   [0]=>   string(30) "in red with new tires and with"   [1]=>   string(22) "red with new tires and" }   What I would like $matches[1] to be is 'red'


Is this correct for an email campaign subject?

Just wondering whether the following sentence is grammatically correct — I was always taught that you shouldn't have two ands within the same sentence.  We are not able to come up with a better subject. The subject below is for both New and Used Motorhomes and New and Used Caravans.     Serious Savings on New and Used Motorhomes and Caravans


How to migrate Ubuntu12.04 to LVM without any data loss

The current system is installed on the traditional disk, now I want to migrate it to LVM managed disk, how can I migrate it without any data loss? I'm working with vSphere, so I can add and remove disk easily, change system to another virtual disk and rebooting are acceptable. Is there someone can help me? Thank you!


If $0<\alpha < 1$ and $d(x,y)$ is metric, show that $((d(x,y))^{\alpha}$ is metric.   It remains for me to show that the triangle inequality, or $((d(x,y))^{\alpha}\leq ((d(x,z))^{\alpha}+((d(z,y))^{\alpha}$, holds.  I begin with the fact that $d(x,y)\leq d(x,z)+d(z,y)$. Then I apply the function:  $(d(x,y))^{\alpha}\leq (d(x,z)+d(z,y))^{\alpha}$  What now? I was thinking of expanding the right side but maybe it is not the best idea? I got a hint where if $a\geq 0, b\geq 0$ and $a+b=1$, then $a^{\alpha}+b^{\alpha}\geq 1$ but I don't really know how to apply this hint.


I know this question has been asked multiple times. Unfortunately none of the other solutions actually work.   So heres my code:   \renewcommand\thesection{\arabic{section}} \renewcommand{\thesubsection}{\alph{subsection}} \renewcommand\thesubsubsection{\roman{subsubsection}}  This works for others. This code however compiles to   1.  a.  ii.  Here ist my MWE:  \documentclass[twoside, ngerman]{scrartcl}   \renewcommand\thesection{\arabic{section}} \renewcommand\thesubsection{\alph{subsection}} \renewcommand\thesubsubsection{\roman{subsubsection}}   \begin{document}   \section{Section heading}     \subsection{Subsection heading}     \subsubsection{Subsubsection heading}  \end{document}   This drives me insane. Is there something that I'm missing?  Thanks very much in advance!


How is $\left(\frac {p-1}{2}\right)! ^2 \equiv -1 \pmod p$. I was using this result for a proof ($x^2$ = -1 (mod p) ) and was stuck on this part. NOTE, this result is only when p is a prime of form 4k+1. note: please don't delete my question without atleast informing me of the reason.


javascript function stops working after div refresh

$(function() {   $(".reqdeb").click(function() {     console.log("Working");     var req_id = $(this).attr("id");     var info = 'id=' + req_id;     if (confirm("Are you sure you want to delete this request?")) {       $.ajax({         cache : false,         type : "POST",         url : "del_req.php",         data : info,         success : function() {         }       });       $(this).parents("tr").animate("fast").animate({         opacity : "hide"       }, "slow");     }     return false;   }); });   This is the code that stops working after a few tries of pressing the button and the code that causes it to stop working is this:  function autoRefresh_div(){     $("#refresh").load("reqs.php");     $("#nrref").load("numreq.php") } setInterval('autoRefresh_div()', 5000);


How can I make ceramic material like this?


I want to download files from torrent to my ubuntu server. I want to install utorrent and download files using torrent. I wanna know if it is possible? I want to download that files on my server directly so I can share them with download link directly.   If it is possible then how will I be able ti get link for that file to share it for downlaod?   Can we do the same using any contropanel? Don't think so. I just want to save those file downloaded from torrent to my server and share their download link to people. Please tell me ow is it possible. I am asking this because I don't want to download the files first on my computer than upload it to server.


Who decides when to hold elections? Any schedule or alert system available?

I was wondering who makes the decision when to arrange elections. If there is some plan/schedule, kindly let me know. Is there any alert or reminder system so that we don't miss elections and casting our vote?


How to make a file (e.g. a .sh script) executable, so it can be run from a terminal

I have a script.sh file and type of this file is shellscript file. I want to make this file as application/x-executable file. How can I make it?


how to replace a specific pattern from all files

suppose I want to replace abc with xyz in all files in a directory. How do I write a script for this ?


How can I force the argument of a summation to not be offset

Right now, my summation looks like this since I have a long bottom argument:  $\sum\limits_{x \in A[1...i-1]} x$     How can I make it so that the x is not so offset by the bottom argument text?


How to show that topological groups are automatically Hausdorff?

On page 146, James Munkres' textbook Topology(2ed),  Show that $G$ (a topological group) is Hausdorff. In fact, show that if $x \neq y$, there is a neighborhood $V$ of $e$ such that $V \cdot x$ and $V \cdot y$ are disjoint.  Noticeably, the definition of topological group in Munkres's textbook differs from that in .  A topological group $G$ is a group that is also a topological space satisfying the $T_1$ axiom, such that the map of $G \times G$ into $G$ sending $x \times y$ into $x \cdot y$ and the map of $G$ into $G$ sending $x$ into $x^{-1}$, are continuous maps.


Can I use multiple regression when I have mixed categorical and continuous predictors?

It looks like you can use coding for one categorical variable, but I have two categorical and one continuous predictor variable. Can i use multiple regression for this in SPSS and if so how? thanks!


How to speed up floating-point to integer number conversion?

We're doing a great deal of floating-point to integer number conversions in our project. Basically, something like this  for(int i = 0; i < HUGE_NUMBER; i++)      int_array[i] = float_array[i];   The default C function which performs the conversion turns out to be quite time consuming.  Is there any work around (maybe a hand tuned function) which can speed up the process a little bit? We don't care much about a precision.


What is the difference between three sentences?

There are three sentences.        He watched TV reading the book. (with no comma between TV and reading)     He watched TV, reading the book. (with a comma between TV and reading)     He watched TV to read the book. (with 'to' between 'TV' and 'reading')      I think that the intervals in the sentences vary by comma or to.  For example, I think that there is no time interval between 'the verb' watch and read in the first sentence (He watched TV reading the book.)  And there is some time interval between 'the verb' watch and read in the first sentence (He watched TV, reading the book.) And there is so much time interval between 'the verb' watch and read in the first sentence (He watched TV to read the book.)  Am I right?


documentclass{book} + mdframed + leftmargin

My problem is when I use documentclass{book} leftmargin and rightmargin has no reaction, but It works with documentclass{article}. How I can fix this? I have to use documentclass{book}.  enter code here\begin{mdframed}[backgroundcolor=lightgray, leftmargin=1cm,rightmargin=1cm,roundcorner=8pt]


I am a new user of ubuntu 20.04. I installed and put swap partition in my laptop's (Dell inspiron 7520) original 30 Gb SSD. My main SSD is 480 Gb, ubuntu is in a 100 Gb partition. I made the WHOLE partition as root (/), so I can't have a /home and a /swap partition in the SAME SSD. Is it possible to REPARTITION my ubuntu installation so I can have a /home and (if possible) a /swap partition located in the same disk? Thanks in advance.


How to run and read cmd/git bash via python code?

I need to write a code that can auto run cmd/git bash based on user input. Then I need to read the result from cmd/git bash to complete the script. Any idea how? -tia


Let $r$ be a relation on $A \times A$ such that $(a,b) r (c,d) \iff ad = bc.$ How can I show that this relation is transitive, ie. $(a, b)r(c,d)$ and $(c,d)r(e, f) \implies (a,b)r(e,f)$?  I tried to say that $(a,b) r (c,d)$ means that $c=ka$ and $d=kb,$ $k$ a coefficient, such that $ad = bc \iff akb = bka,$ and going on from there, but I'm not sure this is valid for all values of $a, b, c,$ and $d$. How can I show the transitivity of the relation?


Seems to be lots of reports for this, but none recently it seems. So, odata feeds are down, i emailed about this but was told to report it here.  Click any of the sites... ie:  and you will see that there is a link to odata, but when you click it you get the page not found page:


How do you select wonders at the beginning of a 7 Wonders game?

At the start of your 7 Wonders game how do you decide which wonder each player gets?   What is the intended default rule? Something I'm unsure about is if you are supposed to mix sides A and B. Is it fair and balanced if some players are playing side B? Are there other ways that your group decides how to pick wonders, which work and are fair?


Python performance: square roots and hot-loop operation strategy

In comparing math.sqrt(…) to the built-in binary operator, … ** 0.5 in a REPL using timeit.timeit(…), it looks as though the binary op has a slight edge over the math module function:    … although I had to crank the number of iterations up to 1,000,000 to be able to get visible differences (note that I did compensate for the module-function lookup overhead by directly importing sqrt from math in the relevant test).  In this case, I haven’t yet delved into checking against more evidently off-the-shelf optimized codepaths – e.g. calling libm functions via an extension or a cython module – as I am trying to stick to my New Year’s resolution not to prematurely optimize more than once a week; , I’m after integer-result correctness before performance.   This is specifically an operation in the hot loop of a currently synchronous image-processing function that uses PIL/Pillow to ‡, which right now is about two orders of magnitude too slow; it can’t be readily cythion-ized or numpy-ized due to currently using Pillow’s vector-drawing API (but FYI, I am not afraid to go the distance with those elements of the problem; for example I already replaced calls into the Pillow ImageStat.Stat package with , which doing that was a demonstrable and not at all premature act of optimization).  My question is: what are the important advantages and disadvantages of both of these methods (and/or any additional square-root methodologies I didn’t name) – both in the general sense as well as those that are specifically germane to the Python math environment? And, more importantly, are these issues eclipsed by other issues, such as the aforementioned overhead concerns like attribute-lookup, function dispatch, and the like?  I have often found that there are straightforward performance answers to each of these elements as a unit, but when Python code needs to meet performance standards, all of these sub-concerns ride the line through a gray area of misunderstanding – I therefore do especially hope to hear from anyone who has worked on a problem such as this and understands what to take seriously.    ‡ The lineage of the halftone code itself stems from .


White logos with transparent backgrounds are problematic

A year ago, .  Today, I checked in to see if the issue has been fixed (it hasn't), and I've found that at least one other site (Pro Webmasters) suffers this same dilemma.  The problem is the way that Stack Exchange chat one-boxes links to network sites.  If you post a link to the main site, it grabs that site's logo.  For example, when you paste meta.stackexchange.com into chat, you get a message that looks like this:    That gets one-boxed in place of the link. It's pretty nice.  But some of the network sites have white text (and possible even white logo) on a transparent background. So against the white background of chat, simply nothing at all appears.  For the original example of UX:    And here's a look at what Pro Webmasters looks like:    We can at least see the logo, but the white, borderless text is lost.  For comparison sake, here's the blue background when the person who sent the message is viewing it:    I'm not certain what the easiest solution would be, and I'm sure there are other network sites that probably suffer the same problem.  At a minimum, I would suggest that any future site designs keep this in mind and at least put a border around the text.  The growing list:


How can I find out what went wrong with a failed Windows update?

This has happened multiple times now - when I shut off my Aspire 7741G-6426 laptop (running Windows 7 and 8.1) at night, it does Updates and then shuts down.  When I fire it up the next morning, I get this msg:     We couldn't complete the updates. Undoing changes. Don't turn off your computer   Why do the updates keep failing, and why doesn't Windows stop trying to apply the updates in the first place after several failed attempts?  Or are these all different instances of updates? Last night/this morning was the most recent.  So, how can I find out what went wrong with a failed Windows update?  UPDATE  The comment reminded me that I wrote an event log viewer a long time ago. Looking at events within the last day, it gives me:  Type: Warning Source: Microsoft-Windows-ApplicationExperienceInfrastructure Time Generated: 03/20/2015 04:35:50 Message: The application (Microsoft SQL Server (2008 and 2008 R2), from vendor Microsoft) has the following problem: Microsoft SQL Server (2008 and 2008 R2) is not supported on this version of Windows. For more information, contact Microsoft. Machine Name: AcerAndroid User Name: NT AUTHORITY\NETWORK SERVICE  Type: Warning Source: Wlclntfy Time Generated: 03/20/2015 04:36:46 Message: The winlogon notification subscriber <TrustedInstaller> is taking long time to handle the notification event (CreateSession). Machine Name: AcerAndroid  Type: Warning Source: Wlclntfy Time Generated: 03/20/2015 04:38:46 Message: The winlogon notification subscriber <TrustedInstaller> took 180 second(s) to handle the notification event (CreateSession). Machine Name: AcerAndroid  Type: Warning Source: Wlclntfy Time Generated: 03/20/2015 04:38:57 Message: The winlogon notification subscriber <TrustedInstaller> failed a critical notification event. Machine Name: AcerAndroid  Type: Warning Source: Microsoft-Windows-ApplicationExperienceInfrastructure Time Generated: 03/20/2015 04:40:22 Message: The application (Microsoft SQL Server (2008 and 2008 R2), from vendor Microsoft) has the following problem: Microsoft SQL Server (2008 and 2008 R2) is not supported on this version of Windows. For more information, contact Microsoft. Machine Name: AcerAndroid User Name: NT AUTHORITY\NETWORK SERVICE  Type: Warning Source: Wlclntfy Time Generated: 03/20/2015 04:41:21 Message: The winlogon notification subscriber <TrustedInstaller> is taking long time to handle the notification event (CreateSession). Machine Name: AcerAndroid  Type: Warning Source: Wlclntfy Time Generated: 03/20/2015 04:43:06 Message: The winlogon notification subscriber <TrustedInstaller> took 165 second(s) to handle the notification event (CreateSession). Machine Name: AcerAndroid  Type: Warning Source: Microsoft-Windows-ApplicationExperienceInfrastructure Time Generated: 03/20/2015 04:44:37 Message: The application (ATI Catalyst Control Center *, from vendor ATI Technologies Inc) has the following problem: To function properly, ATI Catalyst Control Center * must be reinstalled after you upgrade Windows. Machine Name: AcerAndroid User Name: ACERANDROID\Clay   UPDATE 2  I tried John Ball's suggestion, and got to the "Windows Update History" screen in Windows 8.1, but it was blank. When I went back to Windows 7 mode via Windows key+D, I saw this:    UPDATE 3  The Wolverine's link seemed to have worked. This is what I saw after I ran it:    UPDATE 4  Well, that didn't work, after all: I had the same old problem this morning and starting up my laptop. The link to the zipped contents of C:\Windows\Logs\CBS is


How can I instantiate an object from a string containing its classname?

I have the following qualified class name stored in a string:   string className="Project.LogicLayer.FunctionsLayer.Medic";   Now I need a new instance of the class from using that string.  I tried this but it always returns null:  Type t=Type.GetType(className); object = Activator.CreateInstance(t);


When an electron is excited to higher energy levels, it will jump back to the same level from which it was excited. Why does it develop "sentiment" with that level?


World coordinates on vertical grid game for different aspect ratios (Unity)

new to game development and unity so hopefully someone can help.  I want to make a 2D portrait mobile game that will have a grid of constant size where units can move on in Unity.  This should support different aspect ratios. To do that I was thinking to cut sections at the top and bottom of the screen for smaller aspect ratios.  Additionally, I would like the coordinate system to be natural to the grid, so coordinate (0,0) would be the bottom left tile in the grid, (1,0) would be the tile to the right of that,... To illustrate this concept I drew something quickly:    I tried with a script that resizes the size of the orthographic camera to fit the content horizontally. Problem I had with that is that I couldn't get a good coordinate system on the grid after the camera gets resized depending on the aspect ratio since the number of horizontal world units varies depending on the aspect ratio.  Any thoughts on what would be the best way to do this? Thanks!


How to load a taxonomy term with case-sensitive?

I used this      $this->termStorage->loadByProperties(['name' => 'test']);   I got two terms: Test, test. I want to get only one: test  This is working without case-sensitive:       $this->termStorage->getQuery()->condition('name', 'test', '=')->execute();       \Drupal::database()->select('taxonomy_term_field_data', 't')       ->condition('t.name', 'test')       ->fields('t', ['name'])       ->execute()       ->fetchAll();       \Drupal::database()->query("SELECT name FROM taxonomy_term_field_data WHERE name='test'")->fetchAll();


Is it possible to run ntpd with a time that is intentionally distinct from system time?

For example, could I set the ntpd time five minutes ahead of the system time?  I know I can set the time manually without running (or even installing) ntpd, but it's not obvious to me how to run ntpd without it setting the system time.


How to create polygon made from outside points of points shp?

I have DEM Data which is in SHP Format. After interpolating to raster, I need to clip the raster image. To do this, I need to transform the Point SHP into a Polygon SHP using only the outer-most points to create the polygon. A Convex Hull does not produce the required results as shown in the diagram - The red outline is the Convex Hull. The arrows show the areas which should also be clipped.    I Have FME and ArcGIS Advanced.


Detecting Join programmatically using ArcPy?

I have some Python code that is launched from within an ArcMap project. Any joins that the user may have created in the project must be removed in order for my code to run. Unfortunately, the code that removes a join… arcpy.RemoveJoin_management("layer1", "layer2")… also breaks some of the layer properties that are critical to my application (highlighted fields, read-only fields, etc).  If joins are removed by right-clicking the layer in ArcMap and choosing “Remove Joins” the layer properties are left intact.  If I can detect that a join exists from within my code, I will simply exit the code and display a message that the user must manually remove their joins before attempting to run the code. So… Can a Join be detected programmatically?


Fix shapefile with basemap in ArcGIS for Desktop?

How I can fix the shapefile with the basemap in ArcGIS 10.2?  I have transform the basemap projection to GREECE GRID, the same with the shapefile...but they don't fix exactly...  I try to attach a Picture for the theme, but I cannot see it...


Unlocking applications from launcher from the command line

In order to automatically configure fresh installations, I need a way to unlock the default applications from the launcher bar. Don't know where this information is stored, may be editing/substituting the file would be the easiest way.


How to calculate the kinetic energy of supernova ejecta?

I believed I could use $0.5\times M_{ej} V_{ej}^2$, with $M_{ej}$ being the ejected mass and $V_{ej}$ being the velocity of the ejected mass. But I noticed in  and  that the the mean velocity is somehow calculated as following : $V_{mean}=(3/5)^{0.5}\times V_{ej}$. And so the kinetic energy was calculated as : $(3/5)(0.5)\times M_{ej} V_{mean}^2 =(3/10)\times M_{ej} V_{mean}^2$. So is there any explanation for how this factor of $0.3$ or the mean velocity was calculated ?


Bash file descriptor redirection mystery

This is a mystery encountered at work today.  Note that this behavior seems to be specific to a binary that I do not know the contents of, but any ideas as to how this phenomenon could occur would be welcome.  It's not of much consequence whether or not this mystery is solved, but it would be gratifying to know what could cause this.  Basically, it looks like this: With either of these two commands, mystderr contains the output that mybinary printed to stderr (desired behavior): $ ./mybinary 3>&1 1>mystdout 2>&3 3>&- | cat > mystderr $ ./mybinary 3>&1 1>mystdout 2>&3 3>&- | while read line; do echo "$line"; done | grep -P ".*"; done > mystderr  With either of these two commands, mystderr contains nothing, strace shows that perl/grep get the input but do not write to stdout: $ ./mybinary 3>&1 1>mystdout 2>&3 3>&- | perl -pe '/.*/p' > mystderr $ ./mybinary 3>&1 1>mystdout 2>&3 3>&- | grep -P ".*" > mystderr  Why does cat know what to do, but grep doesn't?  Why does just feeding the lines through a bash loop cause grep to figure out what to do?


Suppose that A is a linear map from a Hilbert space H into itself that satisfies  =  for all x, y in H . Show that A is bounded.

Suppose that A is a linear map from a Hilbert space H into itself that satisfies $\langle x,Ay\rangle=\langle Ax,y\rangle$  for all $x, y$ in $H$ . Show that A is bounded.  Please Give me hints to solve the problem.


Combinatorics the number of options for $k$ different balls in n different cells, with at least $1$ ball in each cell

How do I calculate the number of options for $k$ different balls in $n$ cells, with at least $1$ ball in each cell?   Lets say $6$ different balls in $3$ different cells, with at least $1$ ball in each cell.   like this:  $$x_1+x_2+x_3 = 6$$  I would like to see an explanation please and not just the answer.  Thanks!


Short story about a group of sci-fi writers sitting around discussing their profession

A group of science fiction writers are sitting around taking turn discussing their profession, where they get their inspiration from, various things that have happened to them during their careers.  After a series of reasonably normal anecdotes, one of them tells the others that he woke up one morning in a parallel universe, quite similar to the regular world but with enough differences that he could make a living as a science fiction writer simply by writing about everyday occurrences at home. Meanwhile he searched constantly for a way to return.  The others initially take this in good humour before gradually coming to realise that he's serious, and start pointing out various flaws in his story demonstrating how ridiculous this is. Eventually one of them asks if this true, then how did he ever get back home.  The last line is something like      "I didn't", he said sadly. "I'm still here."   (I can't remember if the names used are real sci-fi writers, and a sort of inside joke, or fictional). I would have read it sometime in the mid-80s, probably in an anthology. I think it was in a local library, so the book may have been a few years older.


Problem with rep requirement for comment ability

We have a user Ronnie who asked  yesterday without registering a proper account (or something - I'm not overly familiar with the account system here). He came back today and was unable to login, and therefore unable to comment on his question. So he went off and created   questions to contunie the discussions. Quite understandable of a new user, but those with the rep (me included) rushed to close the dupes.  Is there anything that can be done to improve this situation? IMHO, it's a case of the rep requirement for commenting doing harm.


How to change shortcut key for switching between virtual desktops in windows 10?

In linux I use a shortcut to switch between 4 workspaces: win+1/2/3/4.   I would like to have something like this in Windows 10.  UPDATE SOLUTION 2017, WINDOWS 10x64   Update your windows version to most recent through this  . You may also need  Download and unzip this  (0.9.1) works for me. Change content of file settings.ini to    [KeyboardShortcuts] Switch=LWin Move=LAlt, Shift, Ctrl MoveAndSwitch=LAlt, Shift Previous=Left Next=Right PlusTen=     Run virtual-desktop-enhancer.exe as administrator.


How to decide whether I should use “we” in an essay?

The answers to  question promote a view that the personal pronoun we is acceptable in an academic paper. But I did not see an answer there, or more generally on this site, that discourages the use of we. This question is different to the one mentioned above because it queries whether the word we should be used at all, not just to ask whether I or we is more appropriate.   The economics department at my university (UCT) discourages the use of personal pronouns in an essay – I was marked down in my essay for my use of the word we. At the end of my essay, I wrote      In conclusion, we note that the European sovereign debt crisis created uncertainty in the global financial market, and South Africa was one of many countries that dealt with this.    I decided to use we in my essay because I had grown accustomed to seeing it in mathematics textbooks, so I assumed that it was formal enough. But the economics department says that it is not formal enough.   Even though it seems acceptable to use we in some circles, it seems that it is a point of debate. What guidelines should I be using in order to make my decision about whether to use we or not?* Should I continue to use we as I see fit, except for economics essays? Or, should I apply this rule to all my academic essays (I also study public policy & administration)?  It would ostensibly be silly to have different writing styles emanating from the same person. The problem has not been brought up before, and I have used the word in a number of sociology essays in first year, and one public policy & administration essay in second year. In those essays, I used the word in the following ways.     In this section, we discuss motivations for why provincial government should be restructured.    and      Applying this model to provincial government, we can graph a U-shaped function of long-run average cost.   and     Approaching the question from the side of the teacher, we find that inequality can be caused via culturally insensitive teaching methods.   As a final clarification, I do prefer to use the word.  * Edit: Although it was not initially made clear, I have not been provided with style guides. However, I doubt that I would ask this question if I were provided with style guides. Saying that I should "follow the style guide" makes perfect sense, but doesn't really help me in my situation. I asked this question on academia.SE so that I could ask others to brainstorm ideas about how I could make the decision without a style guide (e.g. how were those rules formed in the first place?).


Upgrading MacBook air from 10.6.8 to Sierra

I have been given a MacBook air by a friend that needs it repaired. The device is running 10.6.8 and has no available recovery disks. I am going to re-image the device and update it to the newest macOS but I have run into a serious problem.    Sierra can only be upgraded to if the device is already running 10.7 Lion. It's not.  I can't access recovery mode through Command + R because that's not a feature on Snow Leopard either.  I don't have recovery disks and even if I did, it's an air and has no disk drive.    What in the world should I do?


Difficulty understanding why acceleration of free fall is lower at the equator than the poles

I have been told that the acceleration of free fall is lower at the equator than at the poles, and that this has to do with the fact that at the equator, you are moving with circular motion so centripetal and centrifugal forces are at play, whereas at the pole this is not the case. I've considered two frames of reference: one at the pole (O) and one at the equator (O'). If a ball is dropped at the equator, then in the reference frame O', there is centripetal force $F$ acting on the ball so the force on the ball is $mg{_{1}}+F = mg{_{2}}$ where $mg{_{1}}$ is the ball's "true" weight while mg${_{2}}$ is the apparent weight, so it makes sense that acceleration of free fall, $g{_{2}}$ is smaller. However, from the reference frame O, the falling ball appears to undergo centrifugal force, $-F$, so $mg{_{1}}-F = mg{_{2}}$ meaning acceleration of free fall would appear greater ($g{_{2}}>g{_{1}}$). This is obviously a contradiction. Where is the flaw in my understanding?


Gerund usage: when can verbs be used as -ing nouns?

I have a question regarding the correct usage of verbs as nouns ending in -ing (I understand that these are referred to as gerunds). Under what circumstance may a gerund be used in place of the verb it is derived from? In particular, is it acceptable for a gerund to be the subject of a sentence? Consider these examples:  1) Analyzing data is difficult.  2) The analysis of data is difficult.  Which of the above examples are correct? If both are correct, is one example preferred over the other?


How can I execute an os/shell command from python

For say in terminal I did cd Desktop you should know it moves you to that directory, but how do I do that in python but with use Desktop with raw_input("") to pick my command?


$a, b, c$ are integers and $a,b,c\geq 4$ If $4abc=(a+3)(b+3)(c+3)$ and $a, b, c$ are all not equal, then what is the value of $a+b+c$.   I tried solving by taking $a\neq b=c$ and couldn't find any integral value which could satisfy the condition.   How to proceed in the problem??


Find the value of $x$, where $\int _0^x(t^3-2t+3)\ dt=4$.

I just found something weird and I have no idea where it is wrong. I used two different approaches.  $\int _0^x(t^3-2t+3)\ dt=4\implies \frac{1}{4}x^4-x^2+3x=4\implies$ approximately $x=1.63$ or $x=-3.09$.  By the fundamental theorem of calculus, $\frac{d}{dx}\int _0^x(t^3-2t+3)\ dt=\frac{d}{dx}4\implies x^3-2x+3=0\implies$ approximately $x=-1.89$.   Could anyone tell me where it went wrong?


Is there a deep freeze type of software for newer versions of Ubuntu?

I am trying to figure out how to go about having a user log into a Ubuntu machine, use it to their heart's content, and when they log off delete all of the user data from that account. All of the stuff I have found thus far is about deleting an account instead of just the data. Any help would be a Godsend. Thanks


Prepared satements with bind_param() in PHP

Is there any way to write this code using prepared statements?  $sql = "SELECT *      FROM exercises      WHERE exercise_id IN (         SELECT DISTINCT e.exercise_id          FROM users u,users_subjects us, exercises e          WHERE u.username='".$_SESSION['username']."' AND us.user_id_fk=u.id AND e.subjects=us.subject_id_fk     );"; $result = $conn->query($sql);   I'm trying this way, but with the sencente ‘IN’, I’m not sure how to do it:  $stmt = $mysqli->prepare("SELECT * FROM exercises where exercise_id in (select distinct e.exercise_id from users u,users_subjects us, exercises e where u.username='".$_SESSION['username']."' and us.user_id_fk=u.id and e.subjects=us.subject_id_fk"); $stmt->bind_param("" ); $stmt->execute(); $stmt->close();


Does 'mean' / 'median' divides area under Probability Density Function (PDF) into half in case of normal distribution which is left/right skewed?

In a perfect normal distribution mean and median are same and they divide area under PDF in half. What happens in case if distribution is left/right skewed? does mean or median divides it in half?


How to quit current state animation correctly?

I've a 'classic' humanoid player with an animation controller and some animations.   This is the code i'm managing state changin          float h = CrossPlatformInputManager.GetAxis ("Horizontal");         if (h < 0) {             m_Animator.SetTrigger ("LeftWalking");         }         else if (h > 0) {             m_Animator.SetTrigger ("RightWalking");         }         else if (m_CharacterController.velocity.magnitude != 0) {             m_Animator.SetTrigger ("Walking");         }         else if (m_Jumping) {             m_Animator.SetTrigger ("Jump");         }         else {             m_Animator.SetTrigger ("Idle");             m_Animator.ResetTrigger ("Walking");             m_Animator.ResetTrigger ("LeftWalking");             m_Animator.ResetTrigger ("RightWalking");             m_Animator.ResetTrigger ("Jump");         }     }   My problem is that after i stop to press my "forward" button (that make my player walking), the walking animation continue to play itself till the end.   This is my state machine   This is options of Walking to Idle state    I'm pretty sure I've to "play" with HasExitTime and/or FixedDuration but i'm not sure...


Does the level requirement of the psychic's Psi-Tech Discoveries refer to class level or character level?

In the list of the psychic's  is Force Field, which says:     You must be at least 3rd level to select this discovery.   Does this mean Psychic level 3 or character level 3?


Generate dynamic XY coordinate labels for dataframe corners in ArcGIS layout

I need to label the four corners of a dataframe as shown in the image. Can this be done with dynamic text scripts?


"Couldn't find any package by regex 'libmwsgl.so' "

While installing libmwsgl shared libraries in Ubuntu 14.04 getting error   Couldn't find any package by regex 'libmwsgl.so'   Trying to open graphs in Tracegraph202 for that I need to install this library.


Preserve image transparency when resizing images

on Stack Exchange using URL modifiers, any transparent elements or backgrounds will be lost in the conversion.  Exactly how the missing transparency is handled can vary depending on the modifier being used, and the size of the image being converted  When testing with a  image:   , , : Transparent background was converted to black , , : Transparent background was converted to white : Image was not modified (Image was smaller than 1024×1024) HTML modifier: Transparency is preserved   When testing with a  image:    , , , , , : Transparent background was converted to black HTML modifier: Transparency is preserved    was marked as  back in 2013, so it seems odd that this issue would still be around.    Original (1000x298): https://i.stack.imgur.com/s1dWm.png      Large Thumbnail (640x191): https://i.stack.imgur.com/s1dWml.png      Medium Thumbnail (320x95): https://i.stack.imgur.com/s1dWmm.png      Small Thumbnail (160x48): https://i.stack.imgur.com/s1dWmt.png      Big Square (160x160): https://i.stack.imgur.com/s1dWmb.png      Small Square (90x90): https://i.stack.imgur.com/s1dWms.png      ?s=64 (64x64): https://i.stack.imgur.com/s1dWm.png?s=64      Custom HTML: <img src="https://i.stack.imgur.com/s1dWm.png" width="400">      -Thanks to , , and  for documenting


Internet access not working in Windows Subsystem for Linux

I tried sudo apt-get update in the new Windows Subsystem for Linux, but I get the following error:    The most relevant parts seem to be the "could not resolve" lines about Ubuntu servers, like:  Could not resolve 'archive.ubuntu.com'


Messed up my .bash_profile remotely, can't ssh back in

I'm using a GNU/Linux system remotely, via SSH.  I mistakenly added something into my $HOME/.bash_profile scriot which causes an error. (To be specific: I added an exec foo command instead of . foo, applied to another bash script without execution permissions, which results in an error.)   Now I can't seem to SSH, SCP or SFTP into my machine: bash, my login shell, tries to run the exec foo command, gets the error and throws me out! I don't have any other account I can access remotely.  Is there something I can do to restore access to the system?  Additional details:   Most ports other than for SSH are unavailable since the machine is behind a firewall. It's a Devuan 3 ASCII (~= Debian 10 Beowulf) system.


A trivial question on the sequences $\{a_n\}$ and $\{a_{n+1}\}$ converging to the same limit using the definition of convergence only

Let's say I didn't know that if a sequence $\{a_n\}$ converges to some number $a$, then all subsequences of $\{a_n\}$ also converge to $a$.  I want to show using the definition of convergence that if $\{a_n\}$ converges to $a$, then $\{a_{n+1}\}$ converges to $a$.   Since $\{a_n\}$ we have for all $\epsilon > 0$, there exists a natural number $N$ such that for all $n \in \mathbb{N}$ $$n \geq N \implies |a_n - a | < \epsilon$$ I'm aware that some books use $n > N$, but this one uses $n\geq N$. Since it doesn't matter, let's stick with $n\geq N$ to be consistent =)  Clearly $n+1 > n \geq N$, so I should be able to deduce from the above implication that  $$|a_{n+1} - a| < \epsilon$$ But I have some doubts. My main question is if I pick any index $m > n$, will I be able to immediately conclude that  $$|a_m - a| < \epsilon$$ In other words, picking an index m > n allows me to "update" the index in $|a_n - a| < \epsilon$ to $|a_m - a| < \epsilon$?


I am working to get a PhD, maybe next year this time around. Currently, this is my second year. I have published 3 papers. All of them are not about one problem but consider different problems. My strategy to find a research idea/problem is given below.  1 - Read papers whose titles are either interesting or I have some apriori understanding of those titles.  2 - Understand those papers as best as I can. That is, I try to understand each detail presented in the paper except the simulation results (this is because I think simulation results are hard to reproduce).  3 - I analyze the paper and try to find a very small problem which can be addressed (i.e. I can solve it) by the methodology of the paper.  4 - If I am successful at step 3 I start working on that problem otherwise I repeat the process from step 1.  By applying this strategy I have been able to write 3 papers and I have submitted a fourth (I am not satisfied with those papers because at very best they can be considered average papers). But my concern is that the problems addressed in those papers do not belong to one area. As far as I have seen, for the profiles of some of the renowned researchers in my field their PhD work is focused on one area. One main thing I console myself with is that almost all of those researchers had good supervisors. My supervisor does not even read the draft/reviews of my papers and the suggestions that he provides during the meetings are so broad that the problem becomes intractable. Under these circumstances what are your opinions: Is there any better strategy to do research?   I will be very thankful to you for providing me suggestions or commenting on my dilemma.


Why does chat make random POST requests?

I noticed that in chat, I get random POST requests, to SE sites that I'm on. For example, as I type this question, it sends a POST request to   http://meta.stackexchange.com/gps/event   If I'm flagging spam on drupal.SE I get this  http://drupal.stackexchange.com/gps/event   What's this for? Is it just here to eat up my internet?


Trying to determine velocity of a falling body with respect to traveled distance and initial speed. I've been provided with the following equation for acceleration as a function of distance and the grav. parameter(constant) of the attracting body :   $a= GM/r^2$  Where:  a - acceleration. GM - gravitational parameter(constant). r - distance to the attracting body.  I have entered inputs for GM and r and integrated this equation with respect to $r$. This obviously yielded total acceleration per traveled distance, in other words $m^2/s^2$ at the given altitude.  How do I proceed to determine velocity at this altitude?


How to normalize my db schema for a quiz application?

I am putting together a quiz application.   (I'm calling each quiz a "challenge")  I have a "challenge" table and a "challenge_question" table which is pretty straightforward.  challenge table: id name num_questions (I want to randomize and only display a certain number of Qs per each challenge)  challenge_question table: id challenge_id question (text of the question) required (some questions will be required to be displayed per each challenge) question_type (here I indicate what type of question: Mult. choice, T/F, Ordering, or Fill-in-the-blank)   Where I'm having trouble in normalization is with the types of question options:  Multiple choice, true/false, ordering, and fill-in-the-blank. I wonder, should I have a separate table for each type of challenge-question-option? Or is it possible to combine these into one somehow..  If I combined all possible options into a single table, it might look be something like this  challenge_options table: id challenge_question_id option (text field, can be used for both multiple choice and for fill-in-the-blank style questions) is_true (boolean field for true/false questions) is_correct (boolean, used to determine multiple choice answer) ordering_option_1  ordering_option_2 ordering_option_3 ordering_option_4 (these ordering fields would store the correct sequence of an ordering style of question)   This really strikes me as less than ideal.  Actually, I don't see how the ordering_options would work out correctly at all.  Wouldn't I need to have each of those be a separate option?  Surely there must be a better way.  Any suggestions/criticisms or alternate approaches?


How to solve Exception in thread "main" java.lang.NullPointerException when copying files/directories

I have this code sample to Copy files and directories from one location to another. But this exception keep showing every time I run the program. Can anyone please help me find out the error?   Exception in thread "main" java.lang.NullPointerException  public void listFilesAndFilesSubDirectories(String directoryName) throws FileNotFoundException, IOException {     File directory = new File(directoryName);     //get all the files from a directory     File[] fList = directory.listFiles();     for (File file : fList) {         if (file.isFile()) {             //System.out.println(file.getAbsolutePath());             System.out.println("File");              File source = new File("C:\\Users\\Core i3\\Desktop\\Check me\\" + file);             File dest = new File("C:\\Users\\Core i3\\Desktop\\New folder");             System.out.println(source);              InputStream is = null;             OutputStream os = null;             try {                 is = new FileInputStream(source);                 os = new FileOutputStream(dest);                 byte[] buffer = new byte[1024];                 int length;                 while ((length = is.read(buffer)) > 0) {                     os.write(buffer, 0, length);                 }             } finally {                 is.close();                 os.close();             }          } else if (file.isDirectory()) {             listFilesAndFilesSubDirectories(file.getAbsolutePath());              System.out.println("Directory");              File source = new File("C:\\Users\\Core i3\\Desktop\\Check me\\" + file);             File dest = new File("C:\\Users\\Core i3\\Desktop\\New folder");              InputStream is = null;             OutputStream os = null;             try {                 is = new FileInputStream(source);                 os = new FileOutputStream(dest);                 byte[] buffer = new byte[1024];                 int length;                 while ((length = is.read(buffer)) > 0) {                     os.write(buffer, 0, length);                 }             } finally {                 is.close();                 os.close();             }          }     }  }


What kind or ordering is used for questions in month/week tabs? Tooltip text says:        But I can't understand sort criteria. All of questions presented in the following picture were asked in December:


Installing Windows programs and Lexmark X4650 printer

I am using Ubuntu 12.04. What software do I need to so I can install Windows programs from CD or flash drive? Is this software in the Ubuntu Software Center or do I download it from a website? At one point I saw a program called Wine for running Windows applications in Ubuntu?  Currently the CD/DVD drive isn't recognized. Also how can I install and use my Lexmark all-in-one printer? The Lexmark website doesn't list Ubuntu 12.04 for downloadable drivers.  I hope my Windows programs are not all garbage because I have Ubuntu and Windows 7 has been deleted.


First of all, English is not my first language, so please excuse me if my question sounds dumb.  Secondly, I've seen  but I don't believe it applies, tho I've been wrong before :P.  For example:   bravely is spelled with one "L" dynamically is spelled with two "L"   What is the rule behind this ?


Need help identifying science fiction short story about a board game

I am trying to identify a short story I once read in a science fiction anthology. It resolves around a father and his children playing a new board game. The originator of the board game is some country or alien race that was recently defeated in a war. The game is wildly popular and addictive, and everyone is playing it.  Apparently, the game is very simple to play, so no one bothers to read all the rules, including the father. You just launch into the game, where you acquire properties and businesses. The father is close to winning the game (he thinks) when his son, who has bothered to read the rules, informs him that the goal is to LOSE all of your businesses and die broke. The children are now brainwashed by the game. The defeated enemy crafted the game to destroy the economy of their conqueror, or something along those lines.


Was there a chance that Thanos would die too?

When Thanos snaps his fingers at the end of the Avengers movie, half of the population of the universe wipes out.   Since Thanos is included in the Universe population, could there be a chance that he would die too?


Which Akame ga KILL! manga should I read if I want to continue the storyline of the anime?

I saw there are various manga with Akame ga KILL! in their names.  The ones I have found are:       Which one should I read if I want to continue the storyline of the anime?


How quickly can the human heart rate rise and fall?

How quickly can the human heart rate rise and lower?  For example lets say a human heart rate is rested and is at 60BPM and that person is suddenly scared to trigger their fight or flight reaction. Lets say their heart rate rises to double (120BPM).  From the above example their rate has gone from 1000ms between beats to 500ms between beats. Can the human heart instantly in one heart beat go from the 1000ms to 500ms between beats or does it need to ramp up? If yes how quickly can the heart rate ramp up?  I understand that each human heart is different, and that the speed increase and decrease will be different from person to person. What I'm looking for is a value that I can safely say the human heart won't exceed.  Similarly the same question goes to your heart going lower.


Proving whether a function on the set of real sequences is a metric

Let $S$ be the set of all real sequences , for $(x_n) , (y_n) \in S$ , let $d \Big((x_n) , (y_n) \Big) :=0 $ if $x_n=y_n , \forall n \in \mathbb Z^+$ otherwise $d \Big((x_n) , (y_n) \Big) :=\dfrac 1{\min \{n :x_n \ne y_n\}}$ , then is $d$ a metric ?   EDIT : I have only difficulty in proving the triangle inequality


In my language we have separate words to chase off each (common) animal, like "tchibe" for dogs, "sheetz" for cats, and "ish" for birds. I can think of only one corresponding word in English: one time I saw Marge from "The Simpsons" telling her cat to "shoo". Is that the word I'm looking for? Could you use it as a mildly insulting slang (more fun than insulting) to address another person?


What's wrong now with fwupd? It was OK since May 1st, 2020 on newly installed Ubuntu 20.04 The following packages have been kept back:    fwupd  0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.


X works but Y does not. Whats the difference between X and Y? And passing them as base reference to foo? class Base { }; class Derived : Base{};  void foo(Base& p) {}  int main() {     Derived x = Derived();     Derived y();      foo((Base&)x);     foo((Base&)y); }


Can the Hubble constant be measured locally?

The Hubble constant, which roughly gauges the extent to which space is being stretched, can be determined from astronomical measurements of galactic velocities (via redshifts) and positions (via standard candles) relative to us. Recently a value of 67.80 ± 0.77 (km/s)/Mpc was published. On the scale of 1 A.U. the value is small, but not infinitesimal by any means (I did the calculation a few months ago, and I think it came out to about 10 meters / year / A.U.). So, can you conceive of a measurement of the Hubble constant that does not rely on any extra-galactic observations?  I ask because, whatever the nature of the expansion described by the Hubble constant, it seems to be completely absent from sub-galactic scales. It is as though the energy of gravitational binding (planets), or for that matter electromagnetic binding (atoms) makes matter completely immune from the expansion of space. The basis for this claim is that if space were also pulling atoms apart, I would naively assume we should be able to measure this effect through modern spectroscopy. Given that we are told the majority of the universe is dark energy, responsible for accelerating the expansion, I wonder, how does this expansion manifest itself locally?   Any thoughts would be appreciated.


Is it OK to contact authors of the research paper requesting an implementation?

Given the research paper itself and having a complete understanding of the proposed system, I could implement the system on my own. If my intention is not to re-implement it myself, but rather study the original implementation(probably by the authors of the paper), I've got the following line of questions    Is it acceptable if I seek the original implementation of the paper?   Is it OK to contact the author(s), and request their implementation by giving a valid reason?   Are IEEE papers intellectual properties, that such a task of seeking implementation is entirely stupid?


What does it mean to have a low quantitative but very high verbal/writing GRE for stats PhD application?

I am applying to statistics and biostatistics PhD programs for next year, and I just got my GRE scores back, and they weren't at all what I expected.  I ended up with a 159V/156Q/6.0AW, which corresponds to 83rd/61st/99th percentile in the verbal/quantitative/analytical writing sections, respectively. So, I have a combined score of 315 with a 6.0 writing.  I understand that most statistics programs place a premium on the quantitative score, and so I am a little worried about my low quantitative score, but I am wondering if the relatively high verbal/writing can offset the weakness there.  For some idea of what kind of student I am, I have about a 3.5 GPA with an applied math major, with a full course in real analysis, mathematical statistics and some graduate level regression theory, and potentially an honors thesis (pending). Since my scores are so atypical compared to other applicants (who typically have much stronger quantitative and lower verbal/writing), I am unsure of what my score means for my application as a whole.  I suppose the question of "do stats programs care?" can be generalized to "do quantitative programs care?". While I see there are some threads on low quantitative scores, there aren't too many about a low quant score combined with a high(er) verbal/writing score.


Is it I'm feeling good or I'm feeling well?

Isn't feeling here a verb of being so you would use the adjective good?


How to find the location of the script that is being executed?

How can I find (if possible) the location of the script that is being executed?  So I have a script that I'll use to do some magic, and I'll need to call it from random locations on a system (this system can be mine, my servers, my friend's PC, my mom's PC, etc).  Now, I need to execute some binaries present along with the script, How can I do that?  Say my script folder has 3 files:    binary1 myScript.sh binary2   Now, this whole folder can be located in "/tmp/scripts", on one system, and in "/home/user/Downloads" on other system(random locations). And I'll need to run this script from, lets say "/home/user/Desktop". So my question is, how can I execute the binary1 and binary2 from my script without knowing their actual path before hand?


Is there some trick to evaluating the following integral

I have been staring at this integral for a while and I don't quite know how to take the first step. Is there some trick that I have to use to manipulate the function first?  Integral in question:  $$\int^{2\pi}_0 \frac{dx}{a + \cos x}$$  Any help/hints/insights is deeply appreciated.


Searching for a key in a trie returning null pointer exceptions

I'm trying to create an insert method for a trie in Java, where the method takes a string as an input, and checks to see if a node for each letter exists in the trie: I've attempted this once with a simple Array, and once with a HashMap as seen here:  Array Approach  // Simple Array approach public class trieNode {     char value = '\n';     final static int ALPHA_SIZE = 26;     int count = 0;     trieNode[] children = new trieNode[ALPHA_SIZE];     boolean isEnd = false; //signifies the end of a word     static trieNode root;     trieNode parent;      //constructor for the class         trieNode(){         for(int i = 0; i < ALPHA_SIZE; i++) {             children[i] = null;          }         }           //add a node to the trie.         static void trieInsert(String word) {              trieNode search = root;             for( int i = 0; i < word.length(); i++) {                 int index = word.charAt(i) - 'a'; //There doesn't seem to be any problem here, for example when the given char is c, index returns 2.                  if(word.charAt(i) == search.children[index].value) { //WHERE THE ERROR OCCURS                     search.children[index].count++;                     search.children[index].isEnd = false;                     search.children[index] = new trieNode();                 }             }             System.out.println(word + " has been added successfully to the trie.");         }   HashMap Approach:  public class TrieNode {     final static int ALPHABET_SIZE = 26;     char value;     boolean isEndOfWord;     boolean isTrieLeaf;     HashMap<Character, TrieNode> children = new HashMap();     int count = 0;     TrieNode root;     TrieNode parent;       TrieNode(){      }      void trieInsert(String word) {         TrieNode search = root;         for(int i = 0; i < word.length(); i++) {             if(search.children.containsKey(word.charAt(i))) {  //WHERE THE ERROR OCCURS                 search.children.get(word.charAt(i)).count++; //increase the count by one.                 search = search.children.get(word.charAt(i)); //this character must already be in the trie, check the rest of the word             }             else {                 search.children.put(word.charAt(i), new TrieNode()); //create a new node in the map for the character.                 search = search.children.get(word.charAt(i)); //move to the newly created node and start the process again.                  search.children.get(word.charAt(i)).count++; //update the base variables for the Trie.                 search.children.get(word.charAt(i)).isEndOfWord = false;             }                  if((word.length()-i) == 1)                     search.children.get(word.charAt(i)).isTrieLeaf = true; //if it's the last word in the trie, change that value to true.         }      }  }   The problem occurs when I test them (ex trieInsert("cat")), I always get a null pointer exception at each if statement, but I was under the assumption that you could use null as a comparison in this manner, and you could set objects equal to null in this case?  Example Test  public class main {      public static void main(String[] args) {         TrieNode Trie = new TrieNode();          Trie.trieInsert("cat");      }  }   Am I missing something, and if so what can I do to fix it.


how can I accurately simulate ballistic physics?

I am trying to find out how to make a cannon or gun that works with the physics simulation. but I have two problems.   I'm not sure how to suddenly apply force behind an object,then remove it. I can't stop the projectile from wedging into the barrel and bouncing around trying to escape.(the alternative is to make is smaller, but it still "bleeds" through the mesh)   how can I use the ridged physics engine to create a ballistic simulation( mortar, gun,etc)?


Let $R=\mathbb{Z}[i]/(3+i)$. Why is this a ring and show that $|R|=10$. I'm not allowed to use isomorphisms for the second bit.  For the first bit I said $(3+i)$ is an ideal, $\mathbb{Z}[i]$ is a ring, and $\mathbb{Z}[i]/(3+i)$ is a quotient group so it is a ring.  Second bit no idea.


Prove the inequality:  $\frac{a}{c+a-b}+\frac{b}{a+b-c}+\frac{c}{b+c-a}\ge{3}$  Where $a,b,c$ are sides of a triangle.  It is clear that $c+a-b$ is positive but how to use it?


$S$ be a collection of subsets of $\{1,...,100\}$ ; any two sets in $S$ has non-empty intersection , what is the maximum possible value of $|S|$?

Let $S$ be a collection of subsets of $\{1,2,...,100\}$ such that any two sets in $S$ has non-empty intersection . Then what is the maximum possible cardinality of $S$ ?


Giving a test lecture, what should I keep in mind?

I hold a PhD in computer science. I've been travelling to conferences presenting my papers and sometimes as part of my teaching assistance duty, I had to give some very simple lectures to students.   I found a position as professor and researcher in a university, and I've been asked to deliver a "test lecture" on a subject I don't know to students from a different background than mine. There will be a body of professors evaluating my teaching skills as well.  I am in the process of preparing the lecture, and realised I am preparing it as a presentation. I was wondering, what should I keep in mind when preparing the lecture? I am used to present in front of (a lot of) people, so that is not a problem. I am also used to prepare presentations for my work, so I was wondering if there is something I should keep in mind while preparing/delivering a lecture which is different from delivering a presentation.  Thank you!


Is it possible to make Blender a Y-up world?

After learning bits and pieces of Maya, 3DS Max, IMAGINE and XSI I noticed that they all have Y-up worlds with Z being used for depth (naturally).  is there a way to make Blender a Y-up world?  and does anyone know why isnt it Y-up in the first place?


Calculating Circular Arc Segment Mid and End Point

I have different types of Circular Arc Segments. My given values are:   the Start Point in Cartesian Coordinates (x_s, y_s) the Start Direction in rad (direction) the Radius of the Arc (radius) the Length of the Arc (length) a value stating if the direction of the Arc is counter clockwise or not   The Start Direction is defined as the bearing used i.e. in road alignments (The bearing is the direction, clockwise from North sometimes stated in degrees, minutes and seconds). In a first step, I am calculating the Centre Point (x_c, y_c) of the Arc Segment, which already works correctly.  I now need to calculate the Mid and End Point of the Arc Segment. At the moment I am using the following to do so ('dist' is the distance along the segment, and therefore 0.5 for the midpoint and 1 for the endpoint):  if arc is clockwise: angle = dist * length / radius if arc is counter-clockwise: angle = - dist * length / radius  x = x_c + radius * cos(direction + angle) (I) y = y_c - radius * sin(direction + angle) (II)   I am aware, that I have to somehow change the signs before 'radius' in (I) and (II) depending on whether the endpoint/midpoint is left/right or above/below x_c/y_c, but I can't figure out how I can do that with my given values.  Did anyone get an idea, how to tackle the problem?


Cannot bootstrap due to ""precise" images in RegionOne with arches [amd64 i386]" error

I am having an issue with installing Juju and bootstrapping. I have the Swift storage setup, and the new bucket gets created. The tools have been synced, and all that looks fine.   However when I attempt to bootstrap I get the error: "Cannot start bootstrap instance: no "precise images in RegionOne with arches."   In another bucket [Glance] I do have the Percise AMD64 image within it. I've even added the line for the "public bucket url." However, juju is still having this same issue.  Error:   juju -v bootstrap 2013-07-31 22:08:05 INFO juju provider.go:115 environs/openstack: opening environment "openstack" 2013-07-31 22:08:06 INFO juju provider.go:417 environs/openstack: bootstrapping environment "openstack" 2013-07-31 22:08:16 INFO juju tools.go:26 environs: reading tools with major version 1 2013-07-31 22:08:16 INFO juju tools.go:53 environs: filtering tools by series: precise 2013-07-31 22:08:16 INFO juju tools.go:76 environs: picked newest version: 1.10.0 2013-07-31 22:08:28 ERROR juju supercommand.go:235 command failed: cannot start bootstrap instance: no "precise" images in RegionOne with arches [amd64 i386] error: cannot start bootstrap instance: no "precise" images in RegionOne with arches [amd64 i386]   The version that I am using is: 1.11.4-raring-amd64  My entire environments file is: [I removed all of the bits about MAAS, Amazon, and local]  default: openstack  environments:   openstack:     type: openstack     admin-secret: f[...]2     control-bucket: juj[..]2a     auth-url: http://127.0.0.1:5000/v2.0/     # default-series: precise     auth-mode: userpass     username: admin     password: [XXXX]     tenant-name: admin     region: RegionOne     public-bucket-url: https://swift.canonistack.canonical.com/v1/AUTH_526ad877f3e3464589dc1145dfeaac60


A Complete Interrogative Sentence, Grammatically Proper, Like a Complete Declarative Sentence?

From what I’ve read, and got, , a complete declarative sentence requests a verb, and arguments.  Does a complete interrogative request this, to get thought of as grammatically proper, too?     She (subject, argument[?]) did (auxiliary verb[?]) not (auxiliary adverb[?]) go (intransitive verb[?]).      Did (auxiliary verb[?]) she (subject, argument[?]) not (auxiliary adverb[?]) go (intransitive verb[?])?   And may you use it, and have it grammatically, and syntactically proper, as     Did she go not?


Prove that for every $a, b\in R\setminus\{0\}$ is correct this inequality:  $$\frac{|a+b|}{1+|a+b|}<\frac{|a|}{1+|a|}+\frac{|b|}{1+|b|}.$$


Can the employer view my Google/YouTube history (on Google Apps Platform)?

I left myself signed in to my work Gmail account on my personal computer. I am not using Chrome. I had an internet session that was not suitable for work. At all. This included Google searches and YouTube searches.  Will my employer be able to identify what I have been searching?


Suppose $(a,b,c,d)\in \mathbb R^4 $ is nonzero. $ M = \left( {\begin{array}{cc} a & -b & -c &-d \\ b & a & -d & c \\ c &d &a &-b \\ d&-c&b&a \end{array} } \right) $.  Is det$(M)$ non-zero?


Proving that not all roots of a cubic polynomial are real

Consider a cubic polynomial $$p(x)=ax^3+bx^2+cx+d$$$a,b,c,d$ are integers such that $ad$ is odd and $bc$ is even.The question is to prove that not all roots of $p(x)$ can be real.  I tried differentiating p(x) to get $$p'(x)=3ax^2+2bx+c$$Now for the cubic equation to have nonreal roots $4b^2-12ac<0$.But I donot see how I can apply the conditions as given in the problem.Any hints to proceed shall be highly appreciated.Thanks.


Structuring a product catalogue in Wordpress

I am trying to create a product based content managed website in Wordpress (by clients request). I have created a custom post type where all the products reside, aptly named 'Products'. The products must be shown in different categories as illustrated by the attached image. Being new to Wordpress I am struggling with how to put this together and would like some advice.  Is it best to create a bunch of categories with corresponding pages. When the link is clicked I then somehow filter all the posts in that category? Just a little advice on how the best way to achieve this if possible. Many thanks in advance.


Existence of certain non-commutative finite monoid

Is there a finite monoid with two elements $a$ and $b$ such that $ab = e$ but $ba \neq e$?


MWE:  \documentclass{article} \begin{document} $\wedge{\small\wedge}{\tiny\wedge}$ \end{document}   All the \wedges have the same size...


Are there hash functions that dynamically take integers a and b, and output h(a) and h(b) such that if a>b we have h(a) > h(b)?


JQuery script for only one checkbox selection at a time

I got my script and it works pretty well (as I planned), but only after complete document loading with all checkboxes. It looks like this:  You can see it disables other checkboxes in required column. But here's the thing. I need to use this script when I creating my entriesm and at first loading my page with this entries look like this:  And after adding new entries script already doesn't work. I think this is about AJAX page reloading, the script is doesn't react to AJAX and don't work as a result. $(document).ready(function () { $('.field-correct :checkbox').change(function() {     var $check = $(this),         $div = $check.parent();     if ($check.prop('checked')) {          $('[name~="choice"], [name$="correct"]').each(function() {               if (!$(this).is(':checked')) {               $(this).prop('disabled', true);               }               });     } else {          $('[name~="choice"], [name$="correct"]').each(function() {               if (!$(this).is(':checked')) {               $(this).prop('disabled', false);               $(this).css('background-color', 'red');               }               });     } }); });  What should I do to make my script work with AJAX too? upd: here's html


Using nmake with wildcards in the makefile

I am attempting to set up an nmake makefile to export our balsamiq mockup files to png files automatically, but I'm afraid I can't make heads nor tails of how to make a generic rule for doing so, without explicitly listing all the files I want exported.  details the command line syntax for exporting the files, and  contains an example which looks like it contains a generic rule for .obj files to .exe files. The makefile I have tried so far looks like this: .bmml.png:     "C:\Program Files\Balsamiq Mockups\Balsamiq Mockups.exe" export $< $@  But this doesn't work. If I simply run nmake (with some outdated png files), nmake just does this: [C:\Temp] :nmake  Microsoft (R) Program Maintenance Utility Version 9.00.30729.01 Copyright (C) Microsoft Corporation.  All rights reserved.   [C:\Temp] :  If I ask it to build one specific file, it does this: [C:\Temp] :nmake "TestFile.png"  Microsoft (R) Program Maintenance Utility Version 9.00.30729.01 Copyright (C) Microsoft Corporation.  All rights reserved.  NMAKE : fatal error U1073: don't know how to make '"TestFile.png"' Stop.  [C:\Temp] :  Any nmake gurus out there that can set me straight? An example makefile which simply makes .dat files from .txt files by copying them, to experiment with, looks like this: .txt.dat:     copy $< $@  this does nothing as well, so clearly I'm not understanding how such generic rules work. Do I need to specify a goal above that somehow lists the files I want?


dot sourcing doesn't work within shell script

I am using WSL and try to automate a build process via shell script. The process starts with sourcing some exported variables from a file, say /asdf/2.3.4./test, containing a single line of exports: export VAR1="test"  Now I try to source this from a shell script build_lib.sh: #!/bin/sh . /asdf/2.3.4/test  Executing this results in an error: me@here:path/to/build$ ./build_lib.sh : not found.sh: 2: ./build_lib.sh: 3: .: Can't open /asdf/2.3.4/test  However, sourcing from the shell directly works just fine: me@here:path/to/build$ env | grep VAR1 me@here:path/to/build$ . /asdf/2.3.4/test me@here:path/to/build$ env | grep VAR1 VAR1=test me@here:path/to/build$  What am I doing wrong with the script?


How could I visit StackExchange when I am on StackOverflow? Now, I input the address of StackExchange to visit it when I am on StackOverflow. Is there another way?