This is my code, I searched on the internet but can not find any solution. While compiling this error message shows up:      Package inputenc Error: Unicode char ﬁ (U+FB01)(inputenc) not set up   for use with LaTeX. ...would achieve the highest second law efﬁ      \documentclass[a4paper,11pt]{report}     \usepackage[utf8]{inputenc}     \usepackage{amsmath}     \usepackage{siunitx}     \usepackage{gensymb}     \usepackage{textcomp}     \usepackage[scaled]{helvet}     \renewcommand\familydefault{\sfdefault}      \usepackage[T1]{fontenc}      \usepackage{geometry}     \geometry{         a4paper,         total={170mm,257mm},         left=20mm,         top=20mm,     }     \begin{document}     Organic rankine cycle has been a topic of highest interest in recent years. Different types of working fluid and design parameters are considered for the augmentation of performance from an ORC based cycle [9–18] . Out of these numerical and experimental analysis, some recent findings are discussed in this section of literature. Meng Zhao et. al. [19] studied the effects of the ORC Operating Conditions on the Engine Performance for an Engine-ORC Combined System. From the conclusion of this study it was found that engine backpressure increases with the decrease of the pump speed and the expander speed. The maximum engine power output increment at the engine speed of 1500 r$/$min and 2100 r$/$min is 5.47 kW and 7.07 kW respectively. The backpressure increment of the engine with ORC system increases with the increasing of cooling water inlet temperature. From the study of Wenqiang Sun et. al. [20] we can see the exergy efficiency analysis of ORC (Organic Rankine Cycle) and ORC-based combined cycles driven by low-temperature waste heat From the conclusion of his study, the exergy efficiency of both systems decreases with the increase of the evaporation temperature of the ORC. The net power output, the refrigerating capacity and the resultant exergy efficiency of the uncoupled ORC-ARC are all higher than those of the ORC-ERC for the evaporation temperature of the basic ORC $>\SI{153}{\degreeCelsius}$, in the investigated application. Li et. al. [21] showed in his study of a cascade organic Rankine cycle power generation system using hybrid solar energy and liquefied natural gas that an equivalent efficiency of 5.99 $\%$ is achieved with isopentane$/$R125 and ETC and the hybrid system has a faster return on solar power investment than a solar ORC. Landelle et. al. [22] explained based on his experimental database report of ORC design and performance comparison, the closed heat source (e.g. thermal solar) case would achieve the highest second law efﬁciency using a subcritical regenerative ORC with R245fa as working ﬂuid, while the open source case would achieve the highest exergetic recovery efﬁciency using a transcritical ORC with R404a. Desai et. al. [23] showed in the study of Thermo-economic comparisons between solar steam Rankine and organic Rankine cycles that the optimum regions of the selection diagrams remain almost unchanged with the change in working ﬂuid, solar collector ﬁeld cost, cycle efﬁciency, power block cost, and location of the plant. However, the cost of energy for a linear Fresnel reﬂector based plant with steam Rankine cycle ($\sim$ 0.422 $\$$\textbackslash kW h) is much higher than parabolic trough collector ~ based plant with steam Rankine cycle ($\sim$ 0.353 $ \$ $\textbackslash kW h).     \end{document}   Can anyone help ?  Thanks in Advance :)

I use TeX Live. See my example:  \documentclass{article} \usepackage[utf8x]{inputenc} \usepackage[english]{babel} \begin{document} Check ligatures: ﬁrst % here I have ligature for "fi" \end{document}   I have Unicode symbol here: ﬁ. When I compile the above LaTeX file I get:  ! Package ucs Error: Unknown Unicode character 64257 = U+FB01  Then I apply the LaTeX system recommendation and compile the following file:  \documentclass{article} \usepackage[utf8x]{inputenc} \usepackage[english]{babel} \DeclareUnicodeCharacter{FB01}{ﬁ}% Here I defined a Unicode ligature \begin{document} Check ligatures: ﬁrst \end{document}   But when I compile this LaTeX file I get:  ! Missing number, treated as zero. <to be read again>                    F l.4 \DeclareUnicodeCharacter{FB01}{ﬁ}  So my question is: How can I input ligatures in a LaTeX file using just the ligature's Unicode symbol?


Here is my initial code: Where I can add textbox by clicking the add button.      The problem is, it can't get the value from the added textbox only the 1st available textbox. How can i get the value from the added textbox?  here is the first row that is already available.
             1	             <input type="text" name="details[]" size="68">	             <input type="text" name="qty[]">	             <input type="text" name="unitprice[]">	             <input class ="txt" type="text" name="totalamount[]">
   And here is my script for getting and sum up the value from the textbox.               Thanks in advance!

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


I'm in Python 3.6.5 and I ran across a strange phenomenon: float('50.0') is not the same as float(50.0), though they are equal to each other.  I ran some code to find the difference. Other than python saying that they aren't the same, I can't find a difference. I'm baffled. I'd love it if someone could explain what is happening here.  Here are my tests:  if float('50.0') is float(50.0):     print("float('50.0') is float(50.0)") else:     print("float('50.0') is not float(50.0)")  if float('50.0') == float(50.0):     print("float('50.0') == float(50.0)") else:     print("float('50.0') != float(50.0)")  if float('50.0') is 50.0:     print("float('50.0') is 50.0") else:     print("float('50.0') is not 50.0")  if float(50.0) is 50.0:     print('float(50.0) is 50.0') else:     print('float(50.0) is not 50.0')  if float(50.0) is float(50.0):     print('float(50.0) is float(50.0)') else:     print('float(50.0) is not float(50.0)')  xstr_float = float('50.0') norm_float = float(50.0) print ('xstr_float: {0:.100f}'.format(xstr_float)) print ('xstr_float is of type:{}'.format(type(xstr_float))) print ('norm_float: {0:.100f}'.format(norm_float)) print ('norm_float is of type:{}'.format(type(norm_float)))   and my results:  float('50.0') is not float(50.0) float('50.0') == float(50.0) float('50.0') is not 50.0 float(50.0) is 50.0 float(50.0) is float(50.0) xstr_float: 50.0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 xstr_float is of type:<class 'float'> norm_float: 50.0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 norm_float is of type:<class 'float'>   Based on some discussion in the comments I've tried the following, getting results that don't answer the question:  x = float(50.0) y = float(50.0) if x is y:     print('x is y') else:     print('x is not y')  x=12345 y=12345 if x is y:     print('x is y') else:     print('x is not y')   results in:  x is y x is y   UPDATE: I've marked an answer that is correct, and based on a comment on that answer I want to show other people who might be confused what I was missing:  When python creates an object it is assigned an ID. is returns true when comparing two objects returns the same ID. Sometimes python will cache and reuse an object. So in the case of x is y we can see that an object is given and reused because the ID is the same. We also see that the ID changes between python sessions:  x=12345 y=12345 if x is y:     print('x is y') else:     print('x is not y') print('x_id: {}'.format(id(x))) print('y_id: {}'.format(id(y)))   results in  x is y x_id: 2476500365040 y_id: 2476500365040   and on the next run it results in  x is y x_id: 2234418638576 y_id: 2234418638576   If for any reason the same object couldn't be reused to represent x and y then x is y would return false.

Why does the following behave unexpectedly in Python?  >>> a = 256 >>> b = 256 >>> a is b True           # This is an expected result >>> a = 257 >>> b = 257 >>> a is b False          # What happened here? Why is this False? >>> 257 is 257 True           # Yet the literal numbers compare properly   I am using Python 2.5.2. Trying some different versions of Python, it appears that Python 2.3.3 shows the above behaviour between 99 and 100.  Based on the above, I can hypothesize that Python is internally implemented such that "small" integers are stored in a different way than larger integers and the is operator can tell the difference. Why the leaky abstraction? What is a better way of comparing two arbitrary objects to see whether they are the same when I don't know in advance whether they are numbers or not?


I've just found, that if you enter a really long Location name in your profile settings (and, of course, save it), then go to the Profile page, the location name won't break or display as ..., and takes up the full available (and not available) place.  This makes the username, title and the description unreadable.   I've also discovered, that this doesn't apply to 'website link', it creates ellipsis (...) if very long.  Here is a screenshot of the issue:    The screenshot was taken on Stack Overflow, but the issue applies to all SE sites, including this one (Meta SE).

Let me start this with : Very long "About me" text squeezes both the left side (flair) and the right side (the section with location, GitHub link, etc.)  Now, the reverse thing has happened:         put a long text in their "location", and it causes the right section to be overly extended, effectively squeezing the About Me section.  When will the squeezing game end?


As I understand, CTRL+ALT+DEL was a feature in Windows Pre "10" (Maybe pre 8?) that was used as a security feature.  I notice I can touch any key now in Windows 10 from the image screen (you know, it has date, time and an image) and my logon screen appears.  What happened to CTRL+ALT+DEL?  If it is not needed now, does that mean more secure? Or that it made no difference in Windows 7?

In previous versions of Windows, you had to press Ctrl + Alt + Delete to logon, or to unlock a locked workstation.  This was because this key sequence was recognized only by the OS and thus other software couldn't intercept it and display a spoofed logon screen to capture passwords.  Starting with Windows 8, you now just have to press Enter to get to the logon screen.  What is to stop someone from writing a fake logon screen?  Did Windows 8 add some sort of new security mechanism to mitigate this security issue?


For instance, in a non-inertial frame of reference, the net force of an object in a circular motion = (Centripetal force - centrifugal force) = 0.  So, my question is... Can the net force = centripetal force - centrifugal force = mass * acceleration?  Or the fictitious force (centrifugal force) is already mass * acceleration in the inertial frame of reference?

In a non-inertial reference frame, the centripetal force is balanced by a centrifugal force. Therefore, shouldn't the net acceleration be zero? Yet, you still feel an acceleration outwards? Why is that?


Brief  Today I ran across an odd issue in Stack Overflow. My reputation doesn't match between my Profile page to the Achievements tab!  I know for a fact that my Profile page is displaying correct information. As you can see from the images below, my Profile page is displaying 135 reputation, while the Achievements tab is showing only 75  Profile page    Achievements tab    How I managed this?  Honestly, I have no idea.  My computer was left logged into my account over the weekend (as I usually do) and I started posting answers again today. Everything seemed fine until I realized one of my answers were accepted but I hadn't received a notification in the Achievements tab. Comments work fine (notifications are sent), but Achievements doesn't display all the reputation I've received today.  How I somewhat solved it  Naturally, my first reaction was to logout and log back in. Maybe this would solve it? Upon logging back in the reputation I had gained prior to this action still doesn't show up, but any reputation gained after the logout/login procedure does. I also checked on another device (my phone - using the app) and the reputation in Achievements doesn't match.  I'm assuming this is a bug, but how can I fix this so that my Achievements tab displays the correct information?

Looks like there is something wrong with reputation calculation:        +2*5 -6*2 = -2...   why there is +6 in reputation popup?  As @Catija said in comment calculation is OK in the profile:        Perhaps the issue is in the top-bar.


Let $A$ be an associative algebra, And let $V$ be a representation of $A$. By $End_{S}(V)$ one denotes the algebra of homomorphisms of representations $V \to V$  Show that $End_{A}(A)=A^{op}$ the algebra with opposite multiplication.

Given a ring $R$, how to prove that $\operatorname{End}_R(R)\cong R^{\mathrm{op}}$, where $R^{\mathrm{op}}$ is the opposite ring of $R$.   I read this proposition somewhere, but I think it is wrong. Because for any given $f\in\operatorname{End}_R(R) $ and any $r$ in $R$, we can get $f(r)$ by $r f(1)$, and $f(1)$can only be $1$, so $\operatorname{End}_R(R)$ is isomorphic to the trivil group.   Is there anything wrong with my logic? Please help me identify where I am wrong in my understanding of $\operatorname{End}_R(R)$. Thanks!


I remember reading this about 3 years ago. The main character is a teenage girl who has to learn how to survive in this new world. I think she’s trying to find her brother with the help of some people she met hiding underground in sewers.  It was a newer book when I read it and it’s written in English.

My son was telling me about a book that he read last year in class that had a picture of a bee on the cover, but where its abdomen is a syringe (with the needle in place of a stinger). It was kind of post-apocalyptic where people were being driven insane by bee stings or something. Somehow he's not even sure of the major plot points. :)  Anyway, we would like to figure out the title and author of this book. Apparently it is fairly recent, and a second book in the series was released this year.


I state I am asking if it is possible and HOW. I note many forum answers are 'you can't' or 'you don't need to on Linux cause it is perfect and wonderful' - none of these answers will help.  Firstly, the HDD in question is SATA 163 GB and contains ONLY backup data like music, video and NO windows programs or installations. I have had a HDD failure in second HDD that is completely FUBAR so have lost my windows installation, this HDD had linux and windows dual boot, HDD is undetectable in BIOS.  The working HDD is 130GB full with capacity of 163GB (it is badly fragmented due to excessive use...). I intend to defrag this drive using USB linux OS (bootable USB with installation files and 'trial') and any other programs that will enable this task. Once this is done I intend to locate which data areas are free (the end of HDD data storage area), create a new partition on this free space, install linux full version and get things working.  +++  I understand fully the following:  I can buy a new HDD for install.  I can get an external hard drive, back up the data.  I also understand that copying off backup hdd and then copying back will do the same as defrag.  I ask this question to find out how to complete this action I have requested and NOT to complete it using the methods unavailable to me at this time.  Thanks

Are there any tools that I can use to defrag my Windows partition from Linux?


I somehow enlarged jpeg wallpaper.  I cannot figure out how to return to original size. Any downloaded jpeg as wallpaper does the same thing.  I am new to Ubuntu and can only use it.  I have no tech training.

Recently updated to 18.04.1 and now I cannot resize my background image from fill screen to center image.  How can I resize the image now that 18 doesnt have the quick resize feature?


Is it possible that during the annual draft a basketball player do not accept the proposal from the team? I mean, e.g. if during draft 2017 there are more teams that would like to choose Markelle Fultz but he would like to play only for Suns is it possible that he refuse any team to be free when Suns has its choose?

I'm asking this question because of my ignorance of the fine aspects of drafts.  Suppose that I'm playing basketball in college (I don't know if the specific sport matters; let's stay with basketball) and I'm good enough to have a decent stab at getting into the NBA. I declare draft eligibility, and on draft night, the Phoenix Suns (say) pick me. Suppose now that I just don't want to play for them, for whatever reason (for example, because it would require me to live in Phoenix long term). Do I have a right to pass on their offer?


(last answer on the first page) is linked to a question which exists no more. I wanted to flag it to get it removed but the question is locked and there is no flag option. How can I report it?

My understanding is that a question is historically locked because the information in it is too valuable for the question to be deleted.   But if the "valuable information" becomes obsolete, what happens then?  We cannot modify the question content, or the answers for a historically locked question, right?


Is this valid, and how can i prove that it holds.  Proof of  $$e^x - 1 \geq x \text{ for } {x:-1 \leq x < 0}$$

The elementary but very useful inequality that $1+x \le e^x$ for all real $x$ has a number of different proofs, some of which can be found online. But is there a particularly slick, intuitive or canonical proof? I would ideally like a proof which fits into a few lines, is accessible to students with limited calculus experience, and does not involve too much analysis of different cases.


Sometimes I want to find a topic in favorite posts. So I think that a searching feature can be added in the future to all communities.

I wonder if it is possible to search in just my favorited questions?  If not, can it be considered as a feature request?


I recently installed Ubuntu 20.04 and it currently runs gnome 3.36. I heard that gnome 3.38 has been released. I have tried everything that I could find on the internet but nothing has worked so far. The software updater does not show any update on gnome either. Please tell me what to do?

I know that GNOME 3.38 is a flagship feature of Ubuntu 20.10, but will we be able to install 3.38 on 20.04 so we don't have to give up the LTS status?


I'm helping my son with Math in high school. He is now learning to solve higher order equations, with for example $x^4$, $x^3$ or $x^5$. The point is that he sees no use in solving these equations (apart from an algebraic challenge) because for him they serve no purpose.  The quadratic equation is easy to illustrate by applying it to a ball you throw upward.   Would you have some examples of real-life systems where higher order equations are used?  Tks!

A formula for solving a polynomial of degree three, see  link; $ax^3+bx^2+cx+d=0$, is  $$\begin{align} x\quad&=\quad       \sqrt[3]{           \left(               \frac{-b^3}{27a^3} + \frac{bc}{6a^2} - \frac{d}{2a}           \right)            +                 \sqrt{               \left(                   \frac{-b^3}{27a^3} + \frac{bc}{6a^2} - \frac{d}{2a}               \right) ^2                 +                \left(                   \frac{c}{3a} - \frac{b^2}{9a^2}               \right) ^3            }       }\\       &+\quad       \sqrt[3]{           \left(               \frac{-b^3}{27a^3} + \frac{bc}{6a^2} - \frac{d}{2a}           \right)            -                 \sqrt{               \left(                   \frac{-b^3}{27a^3} + \frac{bc}{6a^2} - \frac{d}{2a}               \right) ^2                 +                \left(                   \frac{c}{3a} - \frac{b^2}{9a^2}               \right) ^3            }       }       \;-\;\frac{b}{3a} \end{align}$$     Unlike quadratic, cubic, and quartic polynomials, the general quintic   cannot be solved algebraically in terms of a finite number of   additions, subtractions, multiplications, divisions, and root   extractions, as rigorously demonstrated by Abel (Abel's impossibility   theorem) and Galois. However, certain classes of quintic equations can   be solved [...] Source:    At levels of $5^{\text{th}}$ degree polynomials, things are starting to look really serious in my eyes. My question is:     If it is possible to not answer subjectively: When, where and how often do you find polynomials of higher degrees than two in mathematical, pure/applied, research?


Is there a way to identify that someone is scraping my website?

I have A LOT of SHTML pages I want to protect from crawlers, spiders & scrapers.   I understand the limitations of SSIs. An implementation of the following can be suggested in conjunction with any technology/technologies you wish:     The idea is that if you request too many pages too fast you're added to a blacklist for 24 hrs and shown a captcha instead of content, upon every page you request. If you enter the captcha correctly you've removed from the blacklist.   There is a whitelist so GoogleBot, etc. will never get blocked.   Which is the best/easiest way to implement this idea?  Server = IIS    Cleaning out the old tuples from a DB every 24 hrs is easily done so no need to explain that.


I am trying to parametrize a call to pytest like this:  export OPTIONS="tests -k 'not e2e'" pytest ${OPTIONS}   The pytest call fails because of the quotes in the variable. Putting the options directly in the call works fine.  I tried:  pytest ${OPTIONS}  ERROR: file not found: tests -k 'not e2e'  pytest $(eval echo "${OPTIONS}") # removes all quotes ERROR: file not found: e2e  pytest $(printf %s ${OPTIONS})   How can I make the pytest call work in a parametrized way?  UPDATE  This  contains a solution that works:  eval "OPTIONS=($OPTIONS)" # (opt.) convert an existing string to an array  export OPTIONS=(tests -k 'not e2e') pytest "${OPTIONS[@]}"   Thank you very much for pointing that out. I was already searching for hours.

$ ls -l /tmp/test/my\ dir/ total 0   I was wondering why the following ways to run the above command fail or succeed?  $ abc='ls -l "/tmp/test/my dir"'  $ $abc ls: cannot access '"/tmp/test/my': No such file or directory ls: cannot access 'dir"': No such file or directory  $ "$abc" bash: ls -l "/tmp/test/my dir": No such file or directory  $ bash -c $abc 'my dir'  $ bash -c "$abc" total 0  $ eval $abc total 0  $ eval "$abc" total 0


Why am I getting that error? It's causing my app to crash. Every time I test my app on my device the logcat puts out that error and I don't know why. I have a reasonable understanding of what a null pointer exception is and I have search thoroughly for an issue similar to mine. I have tried to reformat the click listener in several ways, made sure I have the correct view ID etc. Here is my code.  public class GridActivity extends AppCompatActivity {  Button dijkstra; Button astar; GridView grid; protected void onCreate(Bundle savedInstanceState) {      super.onCreate(savedInstanceState);     setContentView(R.layout.activity_grid);     dijkstra = findViewById(R.id.dijkstra);     astar = astar.findViewById(R.id.astar);     grid = astar.findViewById(R.id.grid);            dijkstra.setOnClickListener(new View.OnClickListener( ) {         @Override         public void onClick(View v) {               GridViewe geoView = new GridViewe(GridActivity.this);             geoView.Dijkstra( );         }     });     astar.setOnClickListener(new View.OnClickListener( ) {          @Override         public void onClick(View v) {               GridViewe geoView = new GridViewe(GridActivity.this);             geoView.Astar( );          }     });   }  public void setContentView(int activity_grid) { }  @Override public void onStop() {     GridViewe geoView = new GridViewe(GridActivity.this);      if(geoView.dijkstrathread.getStatus()== AsyncTask.Status.RUNNING)        geoView.dijkstrathread.cancel(true);     if(geoView.astarthread.getStatus()==AsyncTask.Status.RUNNING){         geoView.astarthread.cancel(true);     }      super.onStop(); }   }  <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".GridActivity">  <GridView     android:id="@+id/grid"     android:layout_width="match_parent"     android:layout_height="match_parent"   />  <Button     android:id="@+id/dijkstra"     android:layout_width="63dp"     android:layout_height="35dp"     android:layout_weight="1"     android:text="DIJKSTRA"     app:layout_constraintEnd_toEndOf="parent"     app:layout_constraintHorizontal_bias="0.0"     app:layout_constraintStart_toStartOf="parent"     app:layout_constraintTop_toTopOf="parent" />  <Button     android:id="@+id/astar"     android:layout_width="106dp"     android:layout_height="27dp"     android:layout_weight="1"     android:text="A* (A star)"     tools:layout_editor_absoluteX="168dp"     app:layout_constraintEnd_toEndOf="parent"     app:layout_constraintHorizontal_bias="0.0"     app:layout_constraintStart_toStartOf="parent"     app:layout_constraintTop_toTopOf="parent" />

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I did the command by accident whilst trying to fix things not being able to upload files anywhere and now some of my software is refusing to open, including the software centre itself, I'm newish to Ubuntu so I'm not super sure of what I'm doing, definitely learning by my mistakes a bit

I accidently ran  sudo chmod 755 -R /   instead of  sudo chmod 755 -R ./   I stopped it after few seconds, but now there is some problems such as  sudo: must be setuid root   How can I revert permissions back?


I am attempting to set a reverse proxy using the nginx container with a few other containerized app being routed too behind. I have modified the default.config in nginx to below. I have not changed anything in nginx.config.   server {     listen       80;     server_name  localhost;      location / {         root   /usr/share/nginx/html;         index  index.html index.htm;     }      location /mailhog {         proxy_pass http://mailhog:8025;     }      location /httpd {         proxy_pass http://httpd:8080;     }      error_page   500 502 503 504  /50x.html;     location = /50x.html {         root   /usr/share/nginx/html;     } }   My dockerfile uses the nginx image and just replaces the default.config.  Docker run command  docker run -d --name mailhog -p 8025:8025 mailhog/mailhog docker run -d --name httpd -p 8080:80 httpd     docker run -d --name mynginx --link=httpd --link=mailhog -p 80:80 mynginx   When I navigate to / I get the standard nginx index page. Mailhog give a 404 and httpd give a 502. I have tried a couple variations of the docker runs command such as using --expose or not opening any ports. If I navigate the actual url, the apps work fine, just not through the reverse proxy.  I got this strategy from . I have looked at using nginx-proxy but I don't want to use subdomain.domain url pattern.

I have a running web-application at http://example.com/, and want to "mount" another application, on a separate server on http://example.com/en. Upstream servers and proxy_pass seem to work, but for one issue:  upstream luscious {  server lixxxx.members.linode.com:9001; }  server {   root /var/www/example.com/current/public/;   server_name example.com;    location /en {     proxy_pass http://luscious;   } }   When opening example.com/en, my upstream application returns 404 not found /en. This makes sense, as the upstream does not have the path /en.   Is proxy_path the right solution? Should I rewrite "upstream" so it listens to /en instead, as it root path? Or is there a directive that allows me to rewrite the path passed along to upstream?


My wired internet connection is working but wireless is not. I can see wireless networks but when try to connect it just doesn't connect. After I tried several things it finally connected once, but the speed was so poor that it almost wasn't working at all. I tried approaches from         After installing WICD I was not able to see any network icon, usually on desktop screen top right corner. Ubuntu stopped detecting the wifi adapter. After I revoked the switch to WICD, I am back to the the original situation.  I'm able to see wireless networks. I don't think this is an authentication problem (password encryption on router and Ubuntu).

I have purchased a TP-LINK TL-WN823N (EU) V2.0 device, which is a USB device that should work as a Network Interface Card, allowing me to connect my computer to wireless networks. Unfortunately, I am unable to find any wireless networks using this device using either wicd or network-manager (no networks appear in the list of networks supplied by either application).  A CD came with the device claiming "Linux support". The CD contained a URL to a corrupted archive file for downloading installation resources. I try to mask my immense frustration.  Here is the additional dmesg output I receive when I connect the device to my computer (similar content is present when I boot the computer with the device connected):  [17096.009912] usb 2-1.2: new high-speed USB device number 4 using ehci-pci [17096.103501] usb 2-1.2: New USB device found, idVendor=2357, idProduct=0109 [17096.103513] usb 2-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [17096.103527] usb 2-1.2: Product: 802.11n NIC [17096.103529] usb 2-1.2: Manufacturer: Realtek [17096.103530] usb 2-1.2: SerialNumber: 00e04c000001   This is my lsusb, where the offending device corresponds to Bus 002 Device 004:  Bus 002 Device 003: ID 0a5c:5800 Broadcom Corp. BCM5880 Secure Applications Processor Bus 002 Device 004: ID 2357:0109   Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 004: ID 0c45:6433 Microdia  Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub   As lsusb -v:   It seems the device is working to me, but no new interface is found in 'ifconfig':  docker0   Link encap:Ethernet  HWaddr 02:42:6e:bf:92:16             inet addr:172.17.0.1  Bcast:0.0.0.0  Mask:255.255.0.0           UP BROADCAST MULTICAST  MTU:1500  Metric:1           RX packets:0 errors:0 dropped:0 overruns:0 frame:0           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:0            RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)  enp0s31f6 Link encap:Ethernet  HWaddr 30:5a:3a:e1:96:b1             UP BROADCAST MULTICAST  MTU:1500  Metric:1           RX packets:0 errors:0 dropped:0 overruns:0 frame:0           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)           Interrupt:16 Memory:df200000-df220000   lo        Link encap:Local Loopback             inet addr:127.0.0.1  Mask:255.0.0.0           inet6 addr: ::1/128 Scope:Host           UP LOOPBACK RUNNING  MTU:65536  Metric:1           RX packets:412 errors:0 dropped:0 overruns:0 frame:0           TX packets:412 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1           RX bytes:31876 (31.8 KB)  TX bytes:31876 (31.8 KB)   Running 'lshw -class network' as root contains only information about the 'enp0s31f6' interface.  Additionally for sanity, my 'uname -a':  Linux home-z170a-ubuntu 4.4.0-22-generic #39=Ubuntu SMP Thu May 5 16:53:32 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux   I am using Ubuntu 16.04.  My questions are:   Why are no networks present in the list for wicd or network-manager? Why is there no additional network interface created when I plug in the USB device? Is it possible to create this network interface?   Thanks for reading.


I have a class with two friend operator overloadings inside:  template<typename T> class A {     T i;      template <typename L, typename R>     friend auto operator+(const A<L> &l, const A<R> &r) -> A<decltype(l.i + r.i)>;      template <typename L>     friend auto operator+(const A<L> &l, const T &r) -> A<decltype(l.i + r)>; }   I wanted to know how can I create a definition for these functions in a .cpp file (since the declarations are in a header file).  For now I did this but it throws an error:  template <typename L, typename R> auto operator+(const A<L> &l, const A<R> &r) -> A<decltype(l.i + r.i)> {     return Vector3Generic<decltype(l.i + r.i)>(l.x + r.x, l.y + r.y, l.z + r.z); }   The error:  Undefined symbols for architecture x86_64:   "A<decltype((fp.x) + (fp0.x))> operator+<float, float>(A<float> const&, A<float> const&)"   And I absolutely don't know how to define the second operator overload using the parent's T.

Quote from :     The only portable way of using templates at the moment is to implement them in header files by using inline functions.   Why is this?  (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)


I know my Ubuntu 10.10 is no more supported. I want to install JaxoDraw and for that I need to install JRE ( Java Runtime Enviornment ). Is there any way to install it manually? Please help.

Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:  $ sudo apt-get install vlc Reading package lists... Done                Building dependency tree        Reading state information... Done     E: Couldn't find package vlc


Suppose you have a tetrahedron. It doesn't have to be regular. Now suppose you have another tetrahedron contained inside the first tetrahedron. Again do not assume it is regular and do not assume that both tetrahedrons are similar. Could it happen that the perimeter of the tetrahedron in the inside is larger then the tetrahedron on the outside? Whether it is or not prove it. Do a proof by contradiction.  This one is tricky. I have been thinking about this problem for a long time now and do not see any way to come up with a reasonable solution. The help would be greatly appreciated!

Find 2 tetrahedrons $ABCD$ and $EFGH$ such that   $EFGH$ lies completely inside $ABCD$. The sum of edge lengths of $EFGH$ is strictly greater than the sum of edge lengths of $ABCD$.   I am completely stumped on this. Seems very counter intuitive to begin. I now have doubts if a solution exists or not.  Source :


If we launch a spaceship at relativistic speeds, the time on the spaceship, compared with Earth's, will pass slower. After a year on the spaceship, on Earth could have passed several years. And, if the spaceship reaches the speed of light, it would appear stopped in time from Earth's perspective. Assuming we could measure it. On GPS satellites, the inverse happens. They are further away from Earth's gravitational pool than an observer on Earth, so there is a time dilation of 45.9 μs/day. If we could 'see' inside the satellite, everything on it would be moving slightly faster. I am interested about the second case. What is the greatest difference on time dilation (on the 'faster if seen from Earth' side) that an object can have, with an observer on Earth as reference? My guess is that it would be something completely removed from any gravity pool and without speed. My first guess was that 'whithout speed' means that it should be idle on the middle of the void, but speed and time dilation without a reference doesn't make sense. So the object should be 'idle' compared to Earth, moving at the same speed than the planet. Correct me if I am wrong, please.

While it is fairly established that both fast movement and the presence of gravity make time pass slower as compared to a system at rest / free of gravity, does that mean that there is no way for time to pass faster than in vacuum, or does general relativity also have "faster" metrics?  To be more precise, is there any frame into which one could go for a while, and on returning to vacuum less time would have passed there?


I have this stack of 1610 bricks. The stack was built by starting from one brick, and then applying 3 consecutive arrays on it (3 dimensions). I want each brick to be randomly assigned any of 4 fixed colors, but the node I came up with (picture) only seems to assign a single color to the entire stack. What did I do wrong, or what is an alternative way? PS: I want to keep the Arrays (if afterward I want to adjust the distance between the bricks, or the dimensions of the bricks)

I'm learning Blender, and I want to make keys for a keyboard with RBG lights incorporated inside them (final render will be an image, not an animation). I created a low-poly key, with 2 material : 1 for base color, and a second one for the random color. So here is what I did  But now, i simply want to make an array to fill the keyboard. But the colors is not random at all, it stays the same.


I want to change the sizes of sub- and superscripts of formulas as their font size is already set to \scriptsize. Is there a way to decrease the font size of all formulas written in \scriptsize by predefining the size in the preamble?  Thanks!

I am trying to mimic our institute's PPt-template for presentation foils using the beamer-class. The corporate quidelines prescribe the use of Helvetica as the main font. However, package helvet does not provide a good mathematical font. Therefore I want to replace it with the math font from the cmbright package:  \documentclass{beamer}  \usepackage{lmodern} \usepackage[T1]{fontenc}  %main font Helevtica \renewcommand{\familydefault}{\sfdefault} \usepackage{helvet}  %prevent beamer from meddling with math fonts \usefonttheme{professionalfonts}  %following lines borrowed from cmbright.sty \DeclareSymbolFont      {operators} {OT1}{cmbr}{m}{n} \DeclareSymbolFont        {letters} {OML}{cmbrm}{m}{it} \SetSymbolFont      {letters}{bold} {OML}{cmbrm}{b}{it} \DeclareSymbolFont        {symbols} {OMS}{cmbrs}{m}{n} \DeclareMathAlphabet{\mathit} {OT1}{cmbr}{m}{sl} \DeclareMathAlphabet{\mathbf} {OT1}{cmbr}{bx}{n} \DeclareMathAlphabet{\mathtt} {OT1}{cmtl}{m}{n} \DeclareMathAlphabet{\mathbold}{OML}{cmbrm}{b}{it} \DeclareMathSymbol{\alpha}{\mathalpha}{letters}{11} \DeclareMathSymbol{\beta}{\mathalpha}{letters}{12} \DeclareMathSymbol{\gamma}{\mathalpha}{letters}{13} \DeclareMathSymbol{\delta}{\mathalpha}{letters}{14} \DeclareMathSymbol{\epsilon}{\mathalpha}{letters}{15} \DeclareMathSymbol{\zeta}{\mathalpha}{letters}{16} \DeclareMathSymbol{\eta}{\mathalpha}{letters}{17} \DeclareMathSymbol{\theta}{\mathalpha}{letters}{18} \DeclareMathSymbol{\iota}{\mathalpha}{letters}{19} \DeclareMathSymbol{\kappa}{\mathalpha}{letters}{20} \DeclareMathSymbol{\lambda}{\mathalpha}{letters}{21} \DeclareMathSymbol{\mu}{\mathalpha}{letters}{22} \DeclareMathSymbol{\nu}{\mathalpha}{letters}{23} \DeclareMathSymbol{\xi}{\mathalpha}{letters}{24} \DeclareMathSymbol{\pi}{\mathalpha}{letters}{25} \DeclareMathSymbol{\rho}{\mathalpha}{letters}{26} \DeclareMathSymbol{\sigma}{\mathalpha}{letters}{27} \DeclareMathSymbol{\tau}{\mathalpha}{letters}{28} \DeclareMathSymbol{\upsilon}{\mathalpha}{letters}{29} \DeclareMathSymbol{\phi}{\mathalpha}{letters}{30} \DeclareMathSymbol{\chi}{\mathalpha}{letters}{31} \DeclareMathSymbol{\psi}{\mathalpha}{letters}{32} \DeclareMathSymbol{\omega}{\mathalpha}{letters}{33} \DeclareMathSymbol{\varepsilon}{\mathalpha}{letters}{34} \DeclareMathSymbol{\vartheta}{\mathalpha}{letters}{35} \DeclareMathSymbol{\varpi}{\mathalpha}{letters}{36} \DeclareMathSymbol{\varrho}{\mathalpha}{letters}{37} \DeclareMathSymbol{\varsigma}{\mathalpha}{letters}{38} \DeclareMathSymbol{\varphi}{\mathalpha}{letters}{39} \let\upDelta\Delta \let\upOmega\Omega \let\upGamma\Gamma \let\upTheta\Theta \let\upLambda\Lambda \let\upXi\Xi \let\upPi\Pi \let\upSigma\Sigma \let\upUpsilon\Upsilon \let\upPhi\Phi \let\upPsi\Psi  %doesn't seem to have an effect %\DeclareMathSizes{12}{12.5}{10}{10}  \begin{document} \begin{frame}  Some Math E$E$ \end{frame} \end{document}   This works quite well, except that the math letters are somewhat smaller than the normal Helvetica text. Is there a way to scale the fontsize, say by 1.1, if the typesetter is in math mode?


I have xml which have different nodes. I want to build decision tree logic using xml.  Is there any js library to parse xml?

I have a variable string that contains well-formed and valid XML. I need to use JavaScript code to parse this feed.  How can I accomplish this using (browser-compatible) JavaScript code?


The   of  shows that Revision 4 was made by a user who did not yet have full editing privileges. The edit was  by another user with full editing privileges because s/he clicked "improve edit."  Strangely enough, Revision 5 does not appear in the revision history, nor is it displayed on the main post. There isn't even the text saying that an edit was removed during a grace period.  What happened to Revision 5?  Related: , but that is not for an approved edit case.

I don't know how I did manage to do it.  I just ... Oh wait, did I do it actually? I actually simply approved it! You can see it . Apparently, I made no changes myself.  But now I'm struggling to understand how exactly was I able to do it, because in 79% of cases I am greeted with this message:        and in another 20%, this faked "improve" goes through (while I don't change completely anything) and I can haz a binding approval vote :D  And in other 1%,  it when I clicked improve (now I know ).  So it's definitely a bug, but I can't find the exact way of reproing.  Note: earlier there was actually a bug which allowed me to approve an edit by clicking improve and submitting with no changes, then it was fixed and for some time the message I've shown above stopped me constantly, and now there is another bug


I have two tables "basket_products" and "products". I want to update "products" table's "adet" column with "basket_products" "adet" column. And i want to update rows where basket_products.urun = products.urun. I want to use this code and getting error : "The multi-part identifier "basket_products.urun" could not be bound."  update products     set adet = adet - (         select basket_products.adet             from basket_products                 inner join products                on products.urun = basket_products.urun)     where products.urun = basket_products.urun   What's wrong?

I have a database with account numbers and card numbers. I match these to a file to update any card numbers to the account number, so that I am only working with account numbers.   I created a view linking the table to the account/card database to return the Table ID and the related account number, and now I need to update those records where the ID matches with the Account Number.  This is the Sales_Import table, where the account number field needs to be updated:  LeadID  AccountNumber 147         5807811235 150         5807811326 185         7006100100007267039   And this is the RetrieveAccountNumber table, where I need to update from:  LeadID  AccountNumber 147         7006100100007266957 150         7006100100007267039   I tried the below, but no luck so far:  UPDATE [Sales_Lead].[dbo].[Sales_Import]  SET    [AccountNumber] = (SELECT RetrieveAccountNumber.AccountNumber                            FROM   RetrieveAccountNumber                            WHERE  [Sales_Lead].[dbo].[Sales_Import]. LeadID =                                                  RetrieveAccountNumber.LeadID)    It updates the card numbers to account numbers, but the account numbers gets replaced by NULL


In bash, I know how to   history |grep foo   which will give me a list of numbered commands from history containing foo. If I want to run one of those commands with a different argument, I can copy paste using the mouse. I don't want to repeat an exact command. I want to load it at the prompt and change something, then execute it. Is there a way to do so? Up arrow doesn't always work for me.

I use !n where (n) is the line number for executing a line in the history file I want executed at the command prompt which I find via history|less.   But there is a command line history event I wish to manually modify. How can I insert into the command line a history events contents without it actually executing so I can modify and then press return?  Best,


I have the alias  alias moveit='mkdir $1 && find -name "*$1*" -type f -exec mv -t ~/$1 {} +'   But I'm not quite sure what I'm doing wrong. Any help would be much appreciated.  I'm trying to make an alias where typing moveit pdf   Creates a directory called pdf in the current working directory. Searches for all the files that contain pdf in the name within the working directory and all of its subdirectories. Moves those found files into the new folder called pdf.   I know that pdf will return other files that aren't pdfs. I'm essentially trying to create an automatic sorting script.  I have files called:  greatfile[pdf].rar greatfile[txt].rar greatfile[rtf].zip badfile[pdf].zip badfile[txt].zip badfile[rtf].rar okayfile[pdf].tar.bz okayfile[txt].zip okayfile[rtf].rar   And I want to sort these files into folders named pdf, txt and rtf, all in one script, or at least one at a time for now.

I want to know if I can pass an argument with an alias command.  for example:  alias d="dmesg|grep -iw usb|tail -5"    Now d will print the last 5 lines. If I want to use d to print a different number of lines, I have to make change in the alias command declaration of d again.  Is there any way I can modify the declaration of an alias so that I don't have to retype the declaration to change the number of lines. Like incorporating passing the number of lines as an argument while declaring alias for d? Or is there some other method to solve this?


I am trying to sort an ArrayList filled with strings alphabetically. When I call the Sort method the alphabet seems to sort fine, however when there are numbers involved the Sort method seems to sort incorrectly.  Take this code for example:  ArrayList list = new ArrayList ();  list.Add ("img149"); list.Add ("img15"); list.Add ("a");  list.Sort ();  for (int i = 0; i < list.Count (); i++) {     Console.WriteLine (list [i]); }   This seems to print:  a img_149 img_15   the string "a" is sorted fine, but the two other strings are incorrectly sorted. I think I understand why this is as "4" comes before "5" however, 149 is really higher than 15 in which case the string with the 15 should print first.  For my situation, I never know exactly what the strings will be (the strings represent file names in my program), and it is crucial the names are sorted alphabetically with the numbers in order (1, 2, 150, 300, etc.). Does anyone have any ideas on how to rectify this?

Anyone have a good resource or provide a sample of a natural order sort in C# for an FileInfo array?  I am implementing the IComparer interface in my sorts.


I'm not at all a statistician, but in the course of my work I've come across a non-trivial maximum likelihood estimation problem, and I'm looking for ideas and/or references on how to approach it.  The problem is this:  Points $(x,y)$ are drawn randomly according to $$\begin{eqnarray*} x & = & c_x + \sin(\theta + \phi)\\ y & = & c_y + \sin(\theta) \end{eqnarray*} $$ where $c_x$ and $c_y$ are normally distributed with mean zero and unknown variances, $\theta$ is uniformly distributed on $[0,2\pi]$, and $\phi$ is fixed but unknown.  Given many such points $(x,y)$, how can I estimate $\phi$ and the variances of $c_x$ and $c_y$?  Qualitatively, this model places points randomly around an ellipse, with ellipticity determined by $\phi$.  The random variables $c_{x,y}$ serve to thicken the ellipse.  Actually, this model is a slight simplification of what I'm really working with--in the real model both the amplitude of the $\sin$ terms and $\phi$ also have random components--but I reckon if I can do the above problem then that's good progress. I've taken a crack at doing the integrals for a direct MLE of the parameters, but it's quite difficult, even numerically.  So I figured I should consult experts: Is there an efficient solution to this problem?  E.g. perhaps there is some sort of Monte Carlo method for doing this kind of problem?  Edit: It has been suggested that this problem is the same as ellipse fitting.  This is incorrect.  As explained in  (which is where this question is derived from), ellipse fitting gives a biased estimate of $\phi$ and the variances in the above problem.  The paper explicitly states that the above MLE problem gives a superior estimate than ellipse fitting.  Ellipse fitting is not what this question is asking for.

Question: Best way to derive an ellipse formula when given bunch of points (say 60 points which when connected draws an ellipse)?  Background: Using R Momocs library function  which returns confidence ellipse coordinates. Would be nice to abstract those points into a formula.  You can see my ellipse points in the image below;    Any suggestions much appreciated, Thanks


Am I right that here before using Holder's inequality we must prove that beta-function always converges for $x>0,y>0$. Right?

Given $ \beta (x, y) = \int_0^1 t^{x-1}(1-t)^{y-1} dt$, Show that $\beta (x,y)$ converges when $x \gt 0, \space y \gt 0$.  $$\int_0^1 t^{x-1}(1-t)^{y-1} dt = \int_0^{0.5} t^{x-1}(1-t)^{y-1} dt + \int_{0.5}^1 t^{x-1}(1-t)^{y-1} dt$$ Now, according to the text, for the integral from $0$ to $1 \over 2$, $t^{x-1}(1-t)^{y-1} \le t^{x-1}$.  $\int_0^{0.5} t^{x-1} dt \lt {\infty}$ entails that $\int_0^{0.5} t^{x-1}(1-t)^{y-1} dt$ converges.  Well, $t^{x-1}(1-t)^{y-1} \le t^{x-1}$ when $y \ge 1$, not for all $y \gt 0$.  Then the text does something similar for the integral from ${1 \over 2}$ to $1$:  Since $t^{x-1}(1-t)^{y-1} \le (1-t)^{y-1}$,  $\int_{0.5}^1 (1-t)^{y-1} dt \lt {\infty}$ entails that $\int_{0.5}^1 t^{x-1}(1-t)^{y-1} dt$ converges.  Well, $t^{x-1}(1-t)^{y-1} \le (1-t)^{y-1}$ when $x \ge 1$.  So the text shows that $\beta (x,y)$ converges when $x, y \ge 1$.  Did I make a mistake somewhere or misunderstand something?


I inadvertently deleted a directory containing several source code files.  I want them back.  I'm on a Linux Ubuntu machine.  The filesystem is NTSF. I tried using TestDisk, but there are millions of deleted files in this partition.  TestDisk presents a curses interface which allows you to page through the deleted files.  But I can't search for the file I want.  I gave up after 15 minutes.  Is there another tool that allows me to undelete files without having to page through millions of file names? I also looked at ddrescue, but that requires you to save the enture partition.  In my case that's 2 TB.  I don't have another 2TB of free space.

I accidentally removed some files on a NTFS partition  How can I recover them staying inside Linux without rebooting ?


I am struggling with this free space issue on my USB  sudo f3probe --destructive --time-ops /dev/sdd    shows   Good news: The device `/dev/sdd' is the real thing  Device geometry:              *Usable* size: 14.65 GB (30728832 blocks)             Announced size: 14.65 GB (30728832 blocks)                     Module: 16.00 GB (2^34 Bytes)     Approximate cache size: 0.00 Byte (0 blocks), need-reset=no        Physical block size: 512.00 Byte (2^9 Bytes)  Probe time: 4'36"  Operation: total time / count = avg time       Read: 547.7ms / 4814 = 113us      Write: 4'33" / 4192321 = 65us   On the other side df -h output   Filesystem                      Size  Used Avail Use% Mounted on  /dev/sdd                        1,9G  1,4G  442M  77% /media/miki/05DB-E2AB     file -s /dev/sdd /dev/sdd: DOS/MBR boot sector, code offset 0x58+2, OEM-ID "mkfs.fat", sectors/cluster 8, Media descriptor 0xf8, sectors/track 32, heads 64, sectors 3815136 (volumes > 32 MB), FAT (32 bit), sectors/FAT 3720, reserved 0x1, serial number 0x5dbe2ab, unlabeled   And  mount | grep /media/miki/05DB-E2AB /dev/sdd on /media/miki/05DB-E2AB type vfat (rw,nosuid,nodev,relatime,uid=1000,gid=1000,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,showexec,utf8,flush,errors=remount-ro,uhelper=udisks2)   How to explain this?  How can I know the free space?

I was taking a look at a HDD and I found a document (from Toshiba, link: ) that says:  "One Gigabyte (1GB) means 10^9 = 1,000,000,000 bytes using powers of 10. A computer operating system, however, reports storage capacity using powers of 2 for the definition of 1GB = 2 ^30 = 1,073,741,824 bytes, and therefore shows less storage capacity."  Then powers of 10 are bigger than powers of 2, OK.   Example 10^2 = 100 and 2^2 = 4.   But I do not understand the document which says for the same storage capacity:  1GB is 1,000,000,000 bytes (powers of 10) and 1,073,741,824 bytes (powers of 2), then: it shows less storage capacity (the powers of 2). Why is it less? If I see for 1GB more storage capacity in powers of 2 than powers of 10.


I am using Ubuntu 14.04 and I want to save my brightness level, because every time I start the computer the brightness level is at maximum.  $ ls -l /sys/class/backlight total 0 lrwxrwxrwx 1 root root 0 Mai 4 06:50 acpi_video0 -> ../../devices/pci0000:00/0000:00:02.0/backlight/acpi_video0 lrwxrwxrwx 1 root root 0 Mai 4 06:50 intel_backlight -> ../../devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight

The brightness of my laptop is reset to max on every restart. I tried the solution provided at  but had no luck.   This command   cat /sys/class/backlight/acpi_video0/max_brightness   Returns   cat: /sys/class/backlight/acpi_video0/max_brightness: No such file or directory   Then I found that I don't have a folder named acpi_video0, but a folder called intel_backlight:    Every time I increase or decrease the brightness using the brightness control keys, the values in brightness and actual_brightness get updated.  Is there any method I could follow to set the brightness to a fixed value on every boot and vary it as and when I need it using the brightness control keys?


I am creating an app that needs to connect to a MySQL database and do various things. I have created PhP scripts to do all the server-side stuff for me, like connecting to the database and doing CRUD operations. The PhP script will then echo out the results, which is stored in a String in my code for further handling.  However, i am concerned with security. My PhP scripts are open for everyone to use. For instance: "" could be such a script, and what it could do was insert the values in the GET part of the URL into my database.  I know for a fact this isn't safe, but i don't know what to do? The thing is, the PhP script are not linked to/from any where, they are just used in my code only. What i mean by that, is that it is PhP code created to work specifically with my application, so i only ever run them by sending an HTTP request from within the app itself, and i never just run into my browser and type in the address (however, someone else could), which is why i don't think it is very safe.  Any ideas / good suggestions in order to make my scripts safe?  EDIT Here is an example of my code, which i would like to make safe:  $orderGrill = $_GET["getOrder"];     $query = "INSERT INTO grillOrders (`order`, `orderNumber`) VALUES ('{$orderGrill}', {$orderNumber})";   There you can see, how i am just directly using the GET values. But how should i make them safe? I can't use forms since i am running this script from an iPhone app "behind the scenes", so the user can't see the forms.  Thank you

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


I am running Spearman correlation between 2 variables weight and freight both being numeric.  The output I have received from correlation is P value - 0.00E+000 and Rank R Squared is 0.61 and which means they are moderately correlated however I am not able to interpret the p value. Is this because of large number of values I am dealing with? I have 2 million rows of data for both the variables.

I have some pairs of datasets (n=200 or thereabouts), of samples which are non-negative and not normally distributed. I think these pairs of variables are related, probably linearly.   Calculating Spearman's rank correlation on these datasets gives some strange results. The correlation coefficients show that the pairs of variables are weakly, positively correlated (e.g. rho of around 0.4), but the p-values are very low (e.g. 4.1e-10).  My vague understanding of this is that the variables are weakly, positively correlated but the probability of unrelated variables producing the same correlation is very low. Does this mean we can be reasonably certain that a positive correlation exists or have I misunderstood?


I'm getting all the files in a folder and putting them into a string array. The problem I'm having is the string array will not sort right with the pages that have a number larger than 9. What would be the easiest way to get the string array to sort the right way? As you can see the very first pdf is A10C and it should show up under A9C, but it's showing up first. Same thing is happening with B10C:  \\server\archives\PAPER\20140818\NJ-140818-A10C.pdf \\server\archives\PAPER\20140818\NJ-140818-A1C.pdf \\server\archives\PAPER\20140818\NJ-140818-A2C.pdf \\server\archives\PAPER\20140818\NJ-140818-A3C.pdf \\server\archives\PAPER\20140818\NJ-140818-A4C.pdf \\server\archives\PAPER\20140818\NJ-140818-A5C.pdf \\server\archives\PAPER\20140818\NJ-140818-A6C.pdf \\server\archives\PAPER\20140818\NJ-140818-A7C.pdf \\server\archives\PAPER\20140818\NJ-140818-A8C.pdf \\server\archives\PAPER\20140818\NJ-140818-A9C.pdf \\server\archives\PAPER\20140818\NJ-140818-B10C.pdf \\server\archives\PAPER\20140818\NJ-140818-B1C.pdf \\server\archives\PAPER\20140818\NJ-140818-B2C.pdf \\server\archives\PAPER\20140818\NJ-140818-B3C.pdf \\server\archives\PAPER\20140818\NJ-140818-B4B.pdf \\server\archives\PAPER\20140818\NJ-140818-B5C.pdf \\server\archives\PAPER\20140818\NJ-140818-B6C.pdf \\server\archives\PAPER\20140818\NJ-140818-B7C.pdf \\server\archives\PAPER\20140818\NJ-140818-B8C.pdf \\server\archives\PAPER\20140818\NJ-140818-B9C.pdf


I've been a fan of the Star Wars movies since I was a kid, but I've never read any of the books. Every time I've thought about reading them, I change my mind because there is so many books, I don't know where to start.      I don't live anywhere near a public library, and I don't have a lot of money to spend on 200+ books. I'm going to be buying the books for my e-reader with Christmas gift cards.   I've heard about The Thrawn Trilogy by Timothy Zahn, and The Darth Bane Trilogy by Drew Karpyshyn. The Thrawn Trilogy sounds really good, but since Bane isn't in the movies, is it worth it reading about characters I don't know? Is that one of those books I would have to read more in the universe before reading? Is it any good?  I'm interested in learning more about the characters in the original trilogy and the prequels. So, my question is, how do I read them? Do I read them in chronological order? Will I be completely lost if I read them out of order?

I love my sci-fi books, but have never read any of the Star Wars novels. Having looked around there seem to be countless different plots, characters, alternative universes... so I have never picked one up!  My question is, what is a good series of Star Wars stories to start on for someone who has only seen the films, but is interested in reading more about the Star Wars universe?  Sorry I realize this is of course subjective, but I imagine an answer would point me in the direction of a few particular books or series that were most in-line with the main Star Wars plot (i.e. the films), and were considered generally good stories unto themselves.  I am particularly interested in the 'Knights of the Old Republic', having heard some friends ranting about the game. Is it necessary to play the game? Or is it based on a book (or series of books)?


My combined reputation (as shown on my ) yesterday was yet 24k, now it is 27k. Well, today was a quite fruitful day for me, I've hit the repcap on the Unix SE! But it is only 200 rep, and not 3k. Unfortunately I can't show a proof from my flair yesterday, because I didn't save it, but I am sure it was 24k. What has happened, did you change something in the combined flair generation algorithm?

I took a look at my profile, where I stuck my flair. Here's the flair:    However, I don't have 28k rep. According to chat, I have 19.7k.  Note: I know about the combined flair - I've had this in my profile for at least a year. It had been showing me the same as in chat, now it isn't.   What is going on here?  Edit: I'm reporting a bug here, that the combined flair is not showing the correct number, as it has in the past.


I ever saw in a old version of tablet galaxy note that you can create a pdf writing on a tablet, however I do not know if I can obtain an file .tex.

I would like to know if there is a tablet device (iPad, Nexus...etc) on which one can install a full LaTeX environment. By "full", I mean that:   One can produce (compile successfully) from any .tex file the dvi or PDF file. If any package is missing, one can install it manually (or better automatically, as MikTeX).   After searching on Google, it seems to me that there is no such tablet device. Most of the LaTeX editors on tablet device require an internet connection (i.e., they compile .tex on a server). In , the author mentioned that  (for iOS) doesn't require an internet connection. But it looks like it is just a LaTeX editor. I don't know how it works with LaTeX. (Does it provide a mini-LaTeX environment or something else?).  p.s. Of course I don't want to type .tex file on a tablet device for a long time. But sometimes I may need to modify an existing .tex file (e.g., when I find some errors in my paper).


I'm working on a fan theory, and I'm curious if in any iteration of various Kryptonians we have seen one affected by, say, red and green kryptonite at the same time. This doesn't have to be any particular canon, where tv, movies, cartoons, comics, serials.super

I've seen and know some types of Kryptonite and know what its effects are, but is there something canon (or even non-canon) that shows what effects can happen when various different types of Kryptonite influence Superman at the same time?


So I recently got my hands on a old Dell PowerEdge 840 With a Intel Pentium D Processor with a whopping speed at 3.00 GHz, in the bios it says that the system memory is 1024 MB ECC DDR2 even though I should have 2GB.. Anyways, I've tried booting it up with Windows 8.1, Ubuntu Desktop 16.4 and Windows Server 2003, the only thing that actually went through the boot screen was the windows server, the other ones gave me an error saying "No boot device available" when trying to boot them, I would assume its because this machine doesnt support windows 8.1 and ubuntu desktop? Im new to this so there might of been a few flaws in what I just wrote.

For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?


Hello, stack exchange community. I was browsing Facebook timeline and found this photo, maybe someone can suggest how does this photo was captured or maybe some PS technique might be applied to achieve such kind of result.

I came across this photo by Jacob Sutton and wanted to know if someone knew how to get this effect in photoshop?    (source: )


Problem: Find the number for every letter(different letter is a different number) such that this equality holds. $$SEND+MORE=MONEY$$ My solution: Because idea of this problem isn't to solve it's to show algorithm step by step and that algorithm present to the children in school.(so no hard maths).  It's easy to see that $M=1$ (in elementary school you couldn't say that but with showing possibilities ). First case was that $S+M=9$ so that implies $S=8$(with carrying 1) if not $S+M=10$ , $S=9$. But the problem begin with next step letters $E,O$ because I didn't know anything about.

SEND + MORE = MONEY   Each letter represents a single digit number.  No two letters represent the same number. (Ex: if M=1 the no other letter in the problem can equal 1)  So far we've figured out that M=1, O=zero, and S is either 8 or 9  This is a very interesting problem, but we're a bit stuck and don't know where to go from here.


If 99% of an atom empty, and if we say that our body is made of atoms stacked together, then why is our body a solid object, rather than 99% hollow.   I have one probable answer that I think might be correct. Referring to the image below  The one on the left (bigger circles) have 99% of the space empty. Now if we reduce the size of circle, then even though the space is 99% empty, but the overall empty space is very less (compared to bigger circle).  If we take this to an atomic level, then the size of the atom is so slow, that we can imagine a small dot in the center, surrounded by very small empty circular space, and then another atom stacked next to it. Now, the 'empty circular' space is so small, that for all practical purposes we can assume the two centers of circles to be next to each other. And hence our body (or any solid body) does not seem empty.  But then, why doesnt light pass through a solid body. Even though the empty space is very less, there still is empty space right? Is it that the size of photon is much bigger than the size of an atom and hence it is unable to pass through that empty space?  I understand that I am not taking into consideration the inter atomic forces, but even if two atoms were very tightly bonded to one another, there will still be some empty space between them (as described in the diagram).

The ghostly passage of one body through another is obviously out of the question if the continuum assumption were valid, but we know that at the micro, nano, pico levels (and beyond) this is not even remotely the case. My understanding is that the volume of the average atom actually occupied by matter is a vanishingly small fraction of the atom's volume as a whole. If this is the case, why can't matter simply pass through other matter? Are the atom's electrons so nearly omnipresent that they can simultaneously prevent collisions/intersections from all possible directions?


Is there a way i can stop OSX from automatically opening iTunes when iOS device plugged in to charge ? Im currently running OSX 10.13.x But presume the solution would be the same for most versions of OSX

When I connect my iPad or iPhone to my Mac iTunes automatically launches. What is the simplest way to prevent this from happening?


Let $S_n$ be the permutation group of order $n$. What is the maximom order of an element on $\mathbb S_{15}$.  Is there any way to find maximom order of an element in $\mathbb S_{15}$ or find the order of an arbitary element in $\mathbb A_n$ and $\mathbb S_n$

Given the following groups, what is the maximum possible order for an element for   (a) $S_5$ (b) $S_6$ (c) $S_7$ (d) $S_{10}$ (e) $S_{15}$  My book justifies the answer as          (a) The greatest order is $6$ and comes from a product of disjoint cycles of length 2 and 3          (b) The greatest order is $6$ and comes from a cycle of length $6$      The other answers were justified exactly the same way, that is (c) 12, (d) 30, (e) 105  I do not understand how in (a) we even got the number "6" from $S_5$ and what disjoint cycles they are referring to. Could someone at least justify one for me?


According to prevalent formal writing style rules,    Should the phrase be in quotes (as in "thank you" or thank you)? Should T of Thank be capital? Should there be a hyphen?      They did not give him a polite "thank you."   or,     They did not give him a polite Thank-you.   or,     They did not give him a polite "Thank you."   or,     They did not give him a polite thank-you.   etc.

Consider the brief passage:     "I love your work, but calling you 'the artist' {1} just doesn't seem to be   cutting it anymore. What shall I call you?"      "OK. Call me George." {2}   So my instincts tell me to put {1} in single quotes as opposed to no punctuation (or perhaps even italics) but to do the opposite for {2}. Is this right? Why?  Let me expand this one further iteration:     "Wow, that's a great name, especially with this crowd. Maybe for your next book    you should call yourself Ringo."{3}


I'm facing a rather weird problem (at least for me). I'm trying to get the reference in my PhD thesis right, and what I would like is the following:   citations are displayed as footnotes, and they also appear at the end in a general bibliography; the footnote apex is the corresponding number of the reference; the reference in the footnote is a shorter version of the one in the general bibliography: name, journal, volume, date (essentially it just lacks the title entry).   I was able to get it right by means of the answer given in , reported here:  \documentclass{report}  \usepackage{filecontents} \begin{filecontents}{biblio.bib} % biblio.bib @Article{paper1,   author =       {John Smith},   title =        {A title},   journal =      {A Journal},   year =         {2010} } @Article{paper2,   author =       {John Doe},   title =        {A paper},   journal =      {Another journal},   year =         {2009} } @Article{paper3,   author =       {Yuppie Networking},   title =        {My paper},   journal =      {The best journal},   year =         {2000} } \end{filecontents} \usepackage[english]{babel} \usepackage{csquotes} \usepackage[style=numeric-comp]{biblatex} \usepackage[colorlinks=false]{hyperref} \usepackage{manyfoot}  \ExecuteBibliographyOptions{citetracker=true,sorting=none}  % Citation footnotes: use \footnoteA \DeclareNewFootnote{A}  % Vanilla footnotes: use \footnoteB \DeclareNewFootnote{B}  % Number of each bibliography entry in brackets \DeclareFieldFormat{labelnumberwidth}{\mkbibbrackets{#1}}  \makeatletter  \newtoggle{cbx@togcite}  % Citation number superscript in brackets \renewcommand\@makefntext[1]{%   \iftoggle{cbx@togcite}     {\@textsuperscript{\normalfont[\@thefnmark]}\enspace #1}     {\@textsuperscript{\normalfont\@thefnmark}\enspace #1}%   \global\togglefalse{cbx@togcite}}  %--------------------------------------------------------------- % Mostly verbatim from Joseph Wright % http://www.texdev.net/2010/03/08/biblatex-numbered-citations-as-footnotes/  \DeclareCiteCommand{\sfcite}[\cbx@superscript]%   {\usebibmacro{cite:init}%    \let\multicitedelim=\supercitedelim    \iffieldundef{prenote}      {}      {\BibliographyWarning{Ignoring prenote argument}}%    \iffieldundef{postnote}      {}      {\BibliographyWarning{Ignoring postnote argument}}}   {\usebibmacro{citeindex}%    \usebibmacro{sfcite}%    \usebibmacro{cite:comp}}   {}   {\usebibmacro{cite:dump}}  \newbibmacro*{sfcite}{%   \ifciteseen   {}   {\xappto\cbx@citehook{%    \global\toggletrue{cbx@togcite}%    \noexpand\footnotetextA[\thefield{labelnumber}]{%      \fullcite{\thefield{entrykey}}\addperiod}}}}  \newrobustcmd{\cbx@superscript}[1]{%   \mkbibsuperscript{\mkbibbrackets{#1}}%   \cbx@citehook%   \global\let\cbx@citehook=\empty}  \let\cbx@citehook=\empty  %---------------------------------------------------------------  \makeatother  \addbibresource{biblio.bib}  \begin{document} \chapter{Title} \null\vfill\noindent Vanilla footnote.\footnoteB{Vanilla footnote text.} First citation.\sfcite{paper1} Second citation.\sfcite{paper2} Vanilla footnote.\footnoteB{Vanilla footnote text.} First ``multi'' citation.\sfcite{paper1,paper3}  \printbibliography \end{document}   which gives  and bibliography   I slightly modified it in order to remove the title from the footnote, by adding:  %avoid displaying the title in the footnote reference. \AtEveryCitekey{% \ifentrytype{article}{     \clearfield{title}% }{} }   and what I get is indeed what I want, but in the apex of the footnote there is now an extra space before the reference number:    that apparently I am not able to get rid of. Maybe it's just something stupid I'm not seeing, could anyone give me any suggestion?  Thanks,  Fabrizio

I see that the code in many packages and examples contains percent signs % at the end of (many) lines. What are they used for? Do they affect the parsing of those lines?


I have been running Ubuntu for years now with only LTS upgrades. root and /home are separate partitions so I have always kept /home and that served me fine until now. There is only the one user, myself. Since the upgrade to 20.04, there are multiple issues with this user though. Sleep mode is wonky and unreliable, the NVIDIA graphics driver can't be installed since a kernel update, some audio settings don't last beyond a restart. When I create another user, then everything works just fine over there. I strongly suspect that some old config files from way back when are causing me issues, especially since Snaps are a thing. Now, I could of course delete everything, create a whole new user for myself and then play everything back from a backup, which would take hours. Or is there a way to 'rejuvenate' the user settings so that it acts like a fresh system, except my personal files are still there? I have found a way to reset Gnome but apparently the issue lies deeper than that. I would appreciate any suggestions.

My main account got messed up, as I tried to fix it things went downhills.   keyboard mess - tried unity --restore and deleting .gconf2*, fail deleted .* in ~, total havoc. Chromium and Firefox crashes etc.   Now, another user account is fully functioning, but I really want my regular username back.  Is there any way to completely wipe the settings for the messed up account or copy the profile from the functioning user?


So I'm trying to understand bootstrapping,  I watched the following video:    And starting from 2:53 the speaker explains that through bootstrapping we can get a closer inference on the population mean by creating a sample distribution of random samples from our original sample  I tried to visualize this in python with the following code:     However, as you can see, the if I make a sampling distribution of my sample I get a distribution that's centered around the sample mean, not the population mean.   This actually makes sense to me, but because of this result I don't understand the purpose of bootstrapping. Could someone explain how bootstrapping works?  EDIT: I read the answer here:   And it still doesn't make sense to me based on the way that i've visualized it. To me, it seems that I'm only getting information about the sample, not the population.

I recently used bootstrapping to estimate confidence intervals for a project. Someone who doesn't know much about statistics recently asked me to explain why bootstrapping works, i.e., why is it that resampling the same sample over and over gives good results. I realized that although I'd spent a lot of time understanding how to use it, I don't really understand why bootstrapping works.  Specifically: if we are resampling from our sample, how is it that we are learning something about the population rather than only about the sample? There seems to be a leap there which is somewhat counter-intuitive.  I have found a few answers to this question here which I half-understand. Particularly . I am a "consumer" of statistics, not a statistician, and I work with people who know much less about statistics than I do. So, can someone explain, with a minimum of references to theorems, etc., the basic reasoning behind the bootstrap? That is, if you had to explain it to your neighbor, what would you say?


I have recently acquired a cheap top level .sexy domain for around only €30 a year. When I look at the pricing of other new top level domains such as .security they cost much more at a whopping €2850+ a year.  Questions(s):   Who makes money on the sale of domains? Where does my money go after purchasing a domain?

ICANN charges 18¢ per domain name registered regardless of its extension, but I pay $10 for a domain name per year with my registrar.   What do domain name registrars do for its customers to justify this extra $9.82?  Is there something that they do for our domain names other than registering it with ICANN?   I just read about the 7 people who hold the ICANN database key and got a little bit curious to know what the domain name servers do for us to justify this extra amount (12 times the actual fee)?


I'm trying to select the best model by the AIC in the General Mixed Model test. The best model is the model with the lowest AIC, but all my AIC's are negative!   So is the biggest negative AIC the lowest value? Or is the smallest negative AIC the lowest value, because it's closer to 0?   For example is AIC -201,928 or AIC -237,847 the lowest value and thus the best model?

I have calculated AIC and AICc to compare two general linear mixed models; The AICs are positive with model 1 having a lower AIC than model 2.  However, the values for AICc are both negative (model 1 is still < model 2).  Is it valid to use and compare negative AICc values?


I am trying to install windows as a boot camp partition on my main hard drive ssd (after spending countless hours trying to get it installed on the optical bay hard drive).  I assumed this would be simple since o am no longer trying to install to an "external" hard drive. But it has turned out to be just as difficult.  The biggest problem I am encountering is that i have a 2010 15" macbook pro which originally came with an optical drive which i have replaced with a Hard disk and the main drive is now an ssd also I am trying to install windows 7. I tried modifying my info.plist so i could create a USB install of my windows iso but when I create a boot camp partition and hit install it restarts into a gray screen and nothing happens. If I attempt to force restart from this It boots into an apple logo that hangs until it goes to a black screen that says "No bootable device found - please insert a bootable device and hit any key." I then force restarted and held down option and when it loaded it didn't show my USB as a device (only my main ssd drive and my optical bay hard disk).  I found a YouTube video of a Czech guy who used virtual box to start the install and then move it to the desired disk and used refit to access it, but when I installed refit it didn't even show up in my boot devices when I held down option...   My question is how I can go about installing windows 7 on my 2010 macbook pro that has an ssd in the main hard drive and a hard disk on the optical bay drive. It can be installed to either disk but I suppose the ssd would be better since its faster to boot. I have a working ISO (showed working from virtual box installs) and a USB drive.

So I have a 2010 15" macbook pro (MBP6,1) and I replaced the optical drive with a hard disk. I wanted to install windows 7 on the hard disk with boot camp with a USB and ISO image.  After searching I found that I need to modify my plist.info to allow my boot camp to create a bootable USB (since normally it doesn't have the option to create the USB for my model since it came with a disk drive).   After doing so and seemingly having a fine (but long) install process onto the USB. I told boot camp how much space to partition windows on and hit install.  Then the computer restarted. When it came back up it was stuck on a grey apple logo screen forever (I waited 15 minutes to ensure it wasn't just "thinking"). I force restarted and the next time it turned on it got stuck on the grey logo for a bit but then proceeded to go to a black screen that said " No bootable device - please insert a bootable device and hit any key". I tried hitting keys with he USB in but nothing happened.  I had to eventually remove the USB and reset PRAM to get it to boot into osx again  Is there any way to install windows 7 from a usb on my macbook pro using boot camp?


If he can't create a riddle he can't solve then he can't do everything so he is not omnipotent and if he can create a riddle he can't solve then he is not omniscient...So which is it?   (Ok I know it's a bit silly but IS THERE an answer?)   So far no attempt of an answer... How come people only try to answer seriously those and only those questions that are too complicated for them to find an answer to? I aint saying its a paradox but perhaps an antinomy?  Theres a slightly positive comment though. // If you do a search on this stack exchange, you will find plenty of answers to this. The typical phrasing involves creating a rock so heavy he can't lift it, but they are all the same paradox. – Cort Ammon 1 hour ago //  Isnt the correct answer that NOTHING IS BOTH omnipotent and omniscient? Those who claim that god is both, are just trying to flatter him, thinking god is easy to fool?

I see this in The God Delusion by Richard Dawkins:       If God is omniscient, he must already know how he is going to intervene to change the course of history using his omnipotence. But   that means he can't change his mind about his intervention, which   means he is not omnipotent.   Is this argument sound?


I have a Master's degree in Theoretical physics, and I've followed a university course on Nuclear Physics. I want to study the subject in more detail. I'm looking for a complete, but a not introductory, book where I can find both theoretical and experimental descriptions about Nuclear Physics. Does anyone have a suggestion?

I want to self-study nuclear physics in order to understand nuclear reactors and nuclear weapons, what books can you recommend?


I have multiple HP Compaq Elite 8300 CMT (with Core i7-3770 processors) workstations that accept DDR3-1600 (PC3-12800) memory. I was about to order some memory of this specification: "(4x8GB) DDR3-1600 PC3-12800 240 PIN DIMM RAM For AMD AM3 AM3+ Socket MB" but as you may note, it says that it's for an AMD board. Here is an image of the DIMM with its accompanying label (I underlined the "AMD Only" on the label):   I thought that this must be a marketing move, but then upon placing the order the seller contacted me to verify that I was ordering this for AMD and NOT Intel.  (Specifically this RAM is to be for this .)  As per this question: , my own question of whether or not this specific processor (apparently memory addressing moved to the CPU mid 2000s) will support this "HIGH DENSITY RAM" appears to have an answer that's just a big "MAYBE".  For example, in the , it's noted that Intel began supporting high density RAM at some point. The problem is that there doesn't seem to be 1) any detail on when this support began and 2) if BIOS updates or processor microcode updates at any point provided necessary support for any Intel chipsets / CPUs that did not previously have support.  And so we return full circle:  When did Intel start supporting "high density RAM / memory" & will the Core i7-3770 support it?

I was browsing for a RAM upgrade earlier for my system, and came across 'AMD-only' RAM (aka, RAM that only works on AMD chipsets).  This RAM can , and seems to be slightly cheaper than 'normal' RAM.  The RAM prompts a question: is this RAM really restricted to AMD chipsets?  When considering RAM for a system, there are certain considerations to make such as:   Speed (1066MHz, 1600MHz, etc); CAS (latency, lower is better); Generation (DDR2, DDR3, DDR4, etc)   However there is usually no such consideration as chipset compatibility. Sure, it's possible to guarantee that a given stick of memory will work if it's within the bounds of the chipsets listed in the information given by the seller/manufacturer.  For instance if a series of chipsets supported RAM between 1600MHz and 2400MHz, with 9-12 CAS, and on DDR3, it would be possible to list a product as being fully compatible with that series of chipsets if the said RAM was 2000MHz, 10 CAS, and DDR3.  I suspect that's partially the story here. However, is it possible at all for a given stick of memory to be 'AMD-only' or 'Intel-only', and if so, how?


In Halmos' Naive set theory, on p. 35, he writes  An empty union makes sense (and is empty), but an empty intersection does not make sense.  Suppose my index set is $I = \{1, 2\}$ and my indexed sets are defined as $A_i \equiv \{-i, i\}$. Then $A_1 = \{-1,1\}$, $A_2 = \{-2, 2\}$, $\bigcup A_i = \{-2, -1, 1, 2\}$ and $\bigcap A_i = \emptyset$. I don't see why that doesn't "make sense".

The following question come from remarks from Velleman, How to Prove it (pp.82, ex. 14).    Let $F$ denote a family of sets and consider the case where $ F = \emptyset$. Then the statement, $ x \in \cap F$ is always true, regardless of $x$. Thus the intersection of an empty set is the universe of discourse.  Paraphrasing from Velleman, the universe of discourse means different things depending upon the context and sometimes no universe of discourse is used. Thus some mathematicians consider $\cap \emptyset$ to be meaningless.    Since only some mathematicians consider it to be meaningless, this suggests that some mathematicians believe it to have meaning.     In what situations may the intersection of an empty set have meaning?


sorry but i cannot find a link to download adb for Mac..can somebody provide me a link,please?thank you!

When it comes to , I often read recommendations like "Use adb logcat to find some more details". Looking for a good way to backup all my apps including their data,  refers to adb backup and adb restore. In several places one can find ways to remotely do on an Android device with the use of , such as transferring files using adb push or adb pull, accessing the  via adb shell, and more. So ADB seems to be a good thing to have for an Android user.  But how to get this "ADB thingy" on my computer? Not being a developer, installing the entire  seems a bit overkill. Is there a more minimalistic approach available?


I have a new Lenovo idea pad (U410) with Windows 8 pre-installed. I've partitioned the hard drive and I'm able to install Ubuntu without errors. I've done this a couple times, but I'm not sure where to place the boot loader. I have an SSD + standard HD (1TB) on my computer. I believe Windows 8's loader is on the 1 TB drive.  I've tried putting the Ubuntu loader on both drives and while it says there wasn't any errors, I'm unable to load directly into it.  I've tried using EasyBCD but every thing I try there says that it was unable to load Windows.  Right now, in order to get into Ubuntu, in Windows I have to go to Settings > Power > Shift + Restart > Troubleshoot > Advanced options > UEFI Firmware Settings > Restart. Then when it restarts I am able to check a separate drive (the SSD) and that loads GRUB. Then I can choose Ubuntu. If I try choosing Windows from Grub it errors out and I have to restart the computer. This is why I do not want to change the BIOS to load from the SSD first.  So how do I properly clean this mess up and allow me to duel boot? I don't care if I do that through GRUB or through the Windows loader.  Thanks.

I'm absolutely new to Linux. I would like to know how to install Ubuntu alongside the pre-installed Windows 8+ OS.  Should I do it with Wubi, or through the Live USB/DVD?  What steps do I need to take to correctly install Ubuntu?


I have a file that looks like this # ... stuff  @late() def test1():     # ...  @late() def test2():     # ...  I need to get each match after the @late() line and do some work on them. I've tried getting the line after using awk '/^@late()/{getline; print}' $the_file_path. The results are correct but when I iterate over the matches for line in `awk '/^@late()/{getline; print}' $the_file_path` do     echo $line done  I get def test1(): def test2():  As you can see, the "def test1()" and "def test2()" are split at the " ". Desired print output def test1(): def test2():  I've tried surrounding each line in quotes to prevent it from breaking at the space but have had no luck. Can I get a pointer on how to handle this case?

Say I have this file:  hello world hello world   This program  #!/bin/bash  for i in $(cat $1); do     echo "tester: $i" done   outputs  tester: hello tester: world tester: hello tester: world   I'd like to have the for iterate over each line individually ignoring whitespaces though, i.e. the last two lines should be replaced by  tester: hello world   Using quotes for i in "$(cat $1)"; results in i being assigned the whole file at once. What should I change?


My calculator says that the former is 41.67, and that the latter is 83.34. Why is that? Shouldn’t they be equal?

$f(x)$ is a strictly increasing, and continuous, function on $[0,+\infty)$. Consider the integral,  $$\int_0^a f^{-1}(x) dx.$$  Reasoning  The interval $[0,a]$ is "reflected" across the line $y=x$ onto the interval $0 \leq y \leq a.$  $f(x)$ and $f^{-1}(x)$ are symmetric across the line $y=x$. So, the integral is equivalent to the area bounded by $y = 0$, $y=a$, and $f(x)$.  So, "integrating $f$ along an interval on the $y$-axis" is the same as integrating $f^{-1}$ along the same interval on the $x$-axis?  Question  Is my reasoning correct?


Every time I try to download an app called  on my Galaxy note 3 an error message appears,  Unknown error when installing the application "-24 Can anyone please help me?

I have Android 4.1.2 on Samsung galaxy S2  I install an app and get this error:  unknown error during appliaction install -24  googling this line should clearing Google play cache might help  but it didn't work for me. Any other solution?


This is my first time posting on this site so please forgive me if I do something wrong here. I want to try to show that the quotient ring $$\frac{F[x,y,z]}{ \langle xz - (y^2 -1) \rangle}$$ is equal to the intersection of the two polynomial rings $F(x)[y]$ and $F(z)[y]$ where $F$ is some field. In other words, I want to show $$\frac{F[x,y,z]}{ \langle xz - (y^2 -1) \rangle} = F(x)[y] \cap F(z)[y].$$ In $F$. The problem is, I am having a hard time coming up with a reason as to why they are equal in $F$. If anyone could help me, id be greatful.

Let $k$ be a field and $k[x,y,z]$ be the polynomial ring in indeterminates $x,y,z$. Define the quotient ring $$R = k[x,y,z]/(xz - (y^2 + 1)).$$ I want to prove that $R$ is a normal ring. My definition of a normal ring is: A ring $R$ is a normal ring if $R$ is an integral domain that is integrally closed in $\operatorname{frac}(R).$ I think I should show that $R = k(x)[y] \cap k(z)[y]$ in $\operatorname{frac}(R)$, but how can I do this? Also,I know how to show that a polynomial ring say $k[x],$ in one determinant (where $k$ is a field) is a normal ring, but I do not know how to prove that this quotient ring $R$ is a normal ring. Also, it is not very clear to me what will be the correct field of fraction of this ring. Any help will be greatly appreciated!


My linear algebra textbook makes the following statements:     A vector space is frequently discussed in the text without explicitly   mentioning its field of scalars. The reader is cautioned to   remember, however, that every vector space is regarded as a vector   space over a given field, which is denoted by F.   I understand what a field is (), but I'm wondering what is meant by "over a given field"?  I would greatly appreciate it if someone could please clarify this concept.  Thank you.

I am getting a bit confused with the terminology here. I understand that a field means some set of scalars like real numbers but why do we need a field for a vector space? Are not the numerical values used to define a vector are inherent properties of the vector space? Why do we term it like "vector space over real field"? If not numbers, what are the other fields possible for a vector space because you obviously numbers to define the value of magnitude and direction of the vectors?


Suppose an electric field ${\mathbf E}(x,y,z)$, $$E(x)=ax, \quad E(y)=E(z)=0,$$ where $a$ is a constant. So we can calculate its charge density is $$\rho = \varepsilon \nabla\cdot{\mathbf E} = \varepsilon a,$$ which is uniform everywhere!  But why? How could an uniform charge density create a field that point in particular direction?

Let us assume the universe filled with positive charge. About a particular point, all the positive charged particles will be symmetrical. Now consider a sphere of radius $r < \infty$ and apply Gauss law. According to Gauss law the electric flux through the sphere will be some finite value as it contains some positive charge. But by symmetry the electric field through the sphere and hence electric flux will be zero. This is a contradiction.


My ESTA is in its second year. My lease is up on my UK address and I will change addresses in the next few weeks. I am flying to the US on March 1st for another visit. Will my address change affect my ESTA or my 90 day allowance?

I have an old, but still valid ESTA, with the country of residence showing my home country. However, I have recently moved for education in the UK. Do I have to apply for a new one?  Nothing else has changed - country of citizenship, passport, names etc


How do i change the visibility of an existing block programmatically?  I created the block using yml, here's the configuration:   uuid: 67105709-2648-445e-9ddd-8b830a854d8d langcode: en status: true dependencies:   module:     - pixelpin_openid_connect     - system   theme:     - bartik id: openidconnectlogin theme: bartik region: content weight: 0 provider: null plugin: pixelpin_openid_connect_login settings:   id: pixelpin_openid_connect_login   label: 'PixelPin OpenID Connect Login'   provider: pixelpin_openid_connect   label_display: visible visibility:   request_path:     id: request_path     pages: /user/login     negate: false     context_mapping: {  }   The block visibility will change depending on whether a checkbox is checked so i cannot modify the existing block using yml (if that's even possible) unless you can call it in code.

In Drupal 6, I could control block visibility using PHP code in the block UI configuration like:  <?php return MYMODULE_abc() || MYMODULE_def() ; ?>   These functions looked up the current node, taxonomy, etc. to decide on whether to display the block. This PHP option is gone in Drupal 8, but there is a $visibility field in BlockBase. Can I use this to programmatically set the visibility at runtime?


As in title: How can I turn off an Android phone in the same Ethernet remotely using a Windows computer? They are in the same Local Area Network and connected to the same router, the Android phone is connected to the router via WiFi and the Windows computer is connected to the router via a cable. I have tried numerous times to get a solution using Google search with different keywords, and objectively Google isn't very competent in understanding complex sentences and I can't get what I am looking for, see for yourself what the results Google gave: , most of the results are exactly the opposite of what I intended to achieve. I want to connect to the phone wirelessly and send commands through WiFi. I figure I need to use either Telnet or SSH to do this, log into the Android device remotely and use Android terminal commands to shutdown the phone. Unfortunately I have tried telnet and here is the result: C:\Windows\System32>telnet 192.168.1.3 Connecting To 192.168.1.3...Could not open connection to the host, on port 23: Connect failed  I know what this means, this is because telnet port is not open and the telnet server isn't online on the Android phone by default. So naturally I need to install some application on the Android phone that runs the telnet/SSH server and opens the telnet/SSH port, and setup a login and password, so I can connect to the phone remotely and it has to somehow execute the commands. The phone isn't rooted, but I have Android Studio and the phone does have USB Debugging, what tweaks do I need to make in order to enable remote logging? And I don't know how to use Android terminal, is there even a command line interface shell on Android? I don't have any experience with this, however from what I have learned Android is based on Linux and I have some experience in Ubuntu 20.04 LTS WSL, I know I can use these commands: sudo power off shutdown -h now  Android must use something similar. How can I achieve this?  The suggested duplicate:  doesn't answer my question because it shuts down the phone through USB while I have explicitly stated in my question that I want to shutdown the phone wirelessly through WiFi connection.

How do I halt an android phone using adb command? I can reboot, but I don't know how to halt.  I tried shutdown -k wait command, but it did not work.


As the title says, every time when I open Nautilus from unity launcher, it opens with all files being shown. Normally it opens with hidden files being hidden, how can I change it back to that behavior?   My system is Ubuntu 14.04 LTS with Unity, no other WM/DM's are installed.

Whenever I open my files, my hidden files show up. I can hide them but when I open up my files again, they're showing again. How do I make the hidden files invisible permanently?