I was recording with a hypercam, then my computer closed (empty battery), the file is over 2 GB. Is there no way to get back anything of this file? I know there is no media player to play UNDF, but is there really nothing left of the whole file? Its very important so i really hope someone can help me out here!
By accident, I recently removed some videos from my phone. I tried to restoring them with Recuva and TuneUp Utilities and the results were "undf" files.  I tried to open with VLC, Media Player Classic and other video players to no avail. Where/how do I find out the codec for these files?   I would really love to be able to watch these videos again.
Is there a way to fake a dual (second) monitor Is there a way to fake a dual monitor for testing.    I have only one monitor and I have to make an application that is suitable for two monitors.  The second monitor screen should appear as a window on my primary monitor. How do I change my default browser? Is there an option to change my default browser for all my applications? Can I use lens brand X on interchangeable lens camera brand Y? Can't mount ISO file as loop device: Error: “failed to setup loop device” sudo mkdir -p /media/cdrom cd ~ sudo mount -o loop ubuntu-* / mount: ubuntu-*: failed to setup loop device: No such file or directory Prove if $n \in \mathbb N$, then $\frac{1}{2!}+\frac{2}{3!}+\frac{3}{4!}+\cdots+\frac{n}{\left(n+1\right)!} = 1-\frac{1}{\left(n+1\right)!}$   So I proved the base case where $n=1$ and got $\frac{1}{2}$  Then since $n=k$ implies $n=k+1$ I setup the problem like so:  $\frac{k}{(k+1)!}+\frac{(k+1)}{(k+2)!}=1-\frac{1}{(k+2)!}$  After trying to simplify it I got the following:  $\frac{k(k+2)!+(k+1)(k+1)!}{(k+1)!(k+2)!}=1-\frac{1}{(k+2)!}$  However, I'm having trouble simplifying it to match the RHS.  Hints? Windows 10 on asus x44h touchpad scolling not working I have just updated Windows 7 to Windows 10.  My touchpad scolling (right-side) is not working anymore.    I have no idea how to fix this in Windows 10.  I have hit the start button and typed "synaptic", but have found nothing useful.  I used to have an icon on the taskbar that showed where I was touching the touchpad.  I used to be able to right-click that icon to change settings, but Windows 10 has not brought that icon over.  Also, the asus website has no synaptic touchpad drivers available for Windows 10.  I have tried the enaltech drivers, but upon the installation atempt I am told that my hardware is not correct. Pre-1980s Sci-fi movie about killer aliens I initially thought that dark energy must in some way violate conservation of mass and energy since the component of the energy density of space that comes from dark energy is constant, and space is expanding. Therefore, as space expands the energy in the universe that comes from dark energy would increase. I presumed the source of this energy was not coming from the conversion of other types of energy to dark energy, so it must violate conservation.  I decided to Google this and came upon this article:    It says that dark energy does NOT violate conservation and quotes Carroll, Press, and Turner (1992):  "…the patch does negative work on its surroundings, because it has negative pressure. Assuming the patch expands adiabatically [i.e. without loss or gain of heat], one may equate this negative work to the increase of mass/energy of the patch. One thereby recovers the correct equation of state for dark energy: P = – ρ c2. So the mathematics is consistent."  Is there a way to explain this in layman's terms? (The blog attempted to do this, but it was very unclear to me.) More specifically, can you explain where my initial train of thought described above fails when I erroneously concluded that dark energy violates conservation?  Thank you. The difference between two periodic functions converges to zero, is this two functions identical? If $f(x)$ and $g(x)$ are two periodic functions, that is, $f(x+T_1)=f(x)$ and $g(x+T_2)=g(x)$ for every $x \in \Bbb R$. Now that $\displaystyle\lim_{x\to\infty}(f(x)-g(x))=0$.  Conjecture: $f(x) \equiv g(x)$. System.ListException: Before Insert or Upsert list must not have two identically equal elements - Deep Dive I had the following exception thrown at me when trying to process more than one selected records via a custom button in the list view.    Class Code  global class MerchandiseInventoryClass {      webservice static void ConverttoInventory(String[] merchandise_id)    {        //Convert Merchandise collection into Inventory Collection...         Merchandise__c[] merchandise_collection = [SELECT ID,Author__c,Book_Title__c,Edition__c,Publisher__c,Total_Merchandise_QtyTotal_Qty__c,Status__c FROM Merchandise__c WHERE ID = :merchandise_id];          Inventory__c i = new Inventory__c(); //Line 1        List&lt;Inventory__c&gt; newInventory = new List&lt;Inventory__c&gt;();        for(Merchandise__c m : merchandise_collection )        {            if(m.Status__c !='Fully Converted')            {            i.Author__c = m.Author__c ;            i.Book_Title__c = m.Book_Title__c;            i.Edition__c = m.Edition__c;            i.Publisher__c = m.Publisher__c;            i.Qty_Available__c = m.Total_Merchandise_QtyTotal_Qty__c;            i.Merchandise__c = m.Id;            m.Uninventoried_Qty__c = 0;            m.Status__c = 'Fully Converted';            newInventory.add(i);            }        }        insert newInventory;        update merchandise_collection;    }  }   By moving the Line 1 to within the for loop solved the issue for me.  Thanks to this post (refer the Best Answer in that post)    What puzzles me is that WHY i have to instantiate "i" for every iteration within the loop.  Why the list collection ("newInventory") is complaining that are duplicate elements and why should it even confuse in the first place when I am performing an "insert" even ? Unable to see anything after importing .obj file What experiment would disprove string theory? Is it safe to delete from C:\Windows\Installer? How to change the theme of Snap Apps? I am enjoying the new "snap" applications, but apps installed using this method doesn't seem to be using the system gtk theme I have set.   Some use Adwaita or worse, Raleigh.   How can I have them use the standard Ambience theme I'm using across the whole system? How do I reset the Windows XP Administrator password? Dimension of cone of projective variety Windows 10: How to change a theme slideshow time interval? It's all int the title; I find myself unable to set a precise time interval defining how often the background pictures of the theme I am currently using change.  The only similar option available in Windows 10 settings applies only to single background images and not to multiple background images included in a theme.  Thanks in advance,  N. Nignx - worker_connections are not enough I don't know what is going on. I double value for worker connections but it still return error.  server { server_name xxx.com;  root /var/www/web; index index.html index.htm index.php; error_log /var/log/nginx/error.log; location / { proxy_http_version 1.1; proxy_set_header   Host $http_host; proxy_set_header   X-Real-IP $remote_addr; proxy_set_header   Upgrade $http_upgrade; proxy_set_header   Connection "upgrade"; proxy_cache_bypass $http_upgrade; proxy_pass         http://127.0.0.1:7777; }        listen 443 ssl; # managed by Certbot     ssl_certificate /etc/letsencrypt/live/xxx.com/fullchain.pem; # managed by Certbot     ssl_certificate_key /etc/letsencrypt/live/xxx.com/privkey.pem; # managed by Certbot     include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot     ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot  } server {     listen 80;     server_name xxx.com;     return 301 https://$host$request_uri; # managed by Certbot  }   Everything is okej with this code?  ERROR:  Firstly was:  worker_connections are not enough worker_connections are not enough   Now is  27513#0: accept4() failed (24: Too many open files) 27513#0: accept4() failed (24: Too many open files) 27513#0: accept4() failed (24: Too many open files) 27513#0: accept4() failed (24: Too many open files) Why do backslashes appear twice? What's the best way to build a string of delimited items in Java? While working in a Java app, I recently needed to assemble a comma-delimited list of values to pass to another web service without knowing how many elements there would be in advance. The best I could come up with off the top of my head was something like this:  public String appendWithDelimiter( String original, String addition, String delimiter ) {     if ( original.equals( "" ) ) {         return addition;     } else {         return original + delimiter + addition;     } }  String parameterString = ""; if ( condition ) parameterString = appendWithDelimiter( parameterString, "elementName", "," ); if ( anotherCondition ) parameterString = appendWithDelimiter( parameterString, "anotherElementName", "," );   I realize this isn't particularly efficient, since there are strings being created all over the place, but I was going for clarity more than optimization.  In Ruby, I can do something like this instead, which feels much more elegant:  parameterArray = []; parameterArray &lt;&lt; "elementName" if condition; parameterArray &lt;&lt; "anotherElementName" if anotherCondition; parameterString = parameterArray.join(",");   But since Java lacks a join command, I couldn't figure out anything equivalent.  So, what's the best way to do this in Java?