gpg: [don't know]: invalid packet (ctb=6d) I tried sudo apt-get upgrade after sudo apt-get update in my tty4 because my close and minimise button,etc are not showing for any window and I can't even use my keyboard. So when I tried to upgrade it the /usr/bin/dpkg error was thrown and i tried to configure it but it shows ubuntu-keyring error processing package. There's a lot of keyring_get_keyblock failed and invalid keyring, on trying sudo dpkg-reconfigure ubuntu-keyring it says ubuntu-keyring is broken or not fully installed. Please help! It started when an article asked me to purge python and then I deleted a few files that made my inkscape disappear and while trying to fix that I rebooted my system and voila I can't even see any close or minimise or any buttons my terminal isn't working and now I'm stuck with tty.
I am a new Ubuntu user running Ubuntu 13.04.  I've been trying to install and use a DeDRM tool, but I've been having problems doing so. I was following some directions that said I needed a version of Python 2.7, but not anything Python 3.0 or later (because 3.0 versions are missing some necessary libraries?). I tried to install Python 2.7.5.6, but it didn't work. I thought it was probably because I had the later version of Python, so I went through terminal and removed Python 3.3, so I could install the earlier version of Python.  Now that I've uninstalled Python 3.3, a lot of applications no longer work, including the terminal and the Ubuntu Software Center. I have no idea how to fix this problem now.
Ubuntu 14.04, problem when install gstreamer1.0-libav, unmet dependencies Suddenly my Ubuntu stopped playing video. When I open a video, the player suggests that I install  gstreamer1.0-libav. However, it fails to install.  I tried installing it manually, here is the error message:  $ sudo apt-get install gstreamer1.0-libav Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  gstreamer1.0-libav : Depends: libavcodec54 (&gt;= 6:9.1-1) but it is not going to be installed or                                libavcodec-extra-54 (&gt;= 6:9.13) but it is not going to be installed                       Depends: libavformat54 (&gt;= 6:9.1-1) but it is not going to be installed E: Unable to correct problems, you have held broken packages. In Lieb and Loss's Analysis, I saw that they mentioned  $L^1(\mathbb{R}^n) \cap L^2(\mathbb{R}^n)$ dense in $ L^2(\mathbb{R}^n)$ (dense wrt the $L^2$ norm, I think). But I didn't find its proof in the book. So I wonder why it is?    Does this conclusion hold for $L^1(\Omega, \mathcal{F}, \mu) \cap L^2(\Omega, \mathcal{F}, \mu)$ for any measure space $(\Omega, \mathcal{F}, \mu)$?  Are there similar statements if replace $L^1$ with $L^p$, and  $ L^2$ with $L^q$ for $p \leq q \in (0, \infty ]$ or $\in [1, \infty]$?  Thanks and regards! Let $a_1,a_2,a_3,\ldots$ be reals. Prove that if $\sum_{n=1}^{\infty} a_n^{2}$ converges, then so does $\sum_{n=1}^{\infty} \frac {a_n}{n}$.   For this I have shown the case for when $ a_n^{2} \le\frac {|a_n|}{n}$ $\Rightarrow$ $ |a_n|\le\frac {1}{n}$ $\Rightarrow$ $\frac {|a_n|}{n} \le \frac{1}{n^{2}}$ and we know that $\sum_{n=1}^{\infty} \frac {1}{n^{2}}$ converges and hence $\sum_{n=1}^{\infty}\frac {a_n}{n}$ converges by the comparison test. Now considering $ a_n^{2} \ge\frac {|a_n|}{n}$ $\Rightarrow$ $\frac {|a_n|}{n} \le a_n^{2}$ $\rightarrow$ combining the two cases for any n we have: $\frac {|a_n|}{n}\le\frac{1}{n^{2}}+a_n^{2}$ Hence using the comparion test again we know that $\sum_{n=1}^{\infty} a_n^{2}$ converges and $\sum_{n=1}^{\infty} \frac {1}{n^{2}}$ converges hence the sum converges so we can conclude that $\sum_{n=1}^{\infty} \frac {a_n}{n}$ is absoluetly convergent $\Rightarrow$ convergent.  Not to sure if this is correct, any help would be much appreciated, many thanks. Analysis Question Involving Real Numbers Understanding the impact/risk of turning off "verify backup integrity" on SQL backup Currently we use standard maintenance plans for backups on the SQL Server 2005/2008/2008R2/2012 servers in our environment, and the "Verify backup integrity" box has always been checked.  Some of the backups run very long, so I've recommended turning off that option, but management needs me to document the impact and risks of this change.  I understand the use and history of this option, it just seems unnecessary to me to double the time for the backup job when (in my opinion), any error that is likely to occur would occur during the backup step, not during the verify.  Am I wrong? Is it minimal risk to turn this off, if I am backing up to disk and not to streaming tape or something? (We back up over the network to an EMC DD-800 backup appliance, if that is relevant.)  Is there any official MS recommendations for when it is safe to turn this off?   Do you run "verify" on every backup in your environment? Do you spot-check them?  EDIT: To clarify, when you check "verify backup integrity" in the maintenance plan, SQL will do a full RESTORE VERIFYONLY on each database immediately after each backup. This is just as data/IO intensive as the original backup, and (basically) doubles the overall time of the backup job. This is not the same as enabling the "checksum" option on backup (which can't be done in the wizard, as far as I know). Remote Desktop Settings Missing I'm trying to setup remote connection to my Windows 10 machine. During the setup I noticed that my installation is missing some settings all the tutorials have. Can anyone tell me why I'm stupid and what I should do? Below you can find a screenshot of what I'm talking about. The first image is how it should be. The second picture is a screenshot on my machine.      Edit: After popular request, my windows version: What effect does serial downvoting have on my rep cap? So I was the victim of serial downvoting the other day, and just had it automagically reversed. Rather than simply removing the previous votes, I was given a bonus lump of rep with the reason "serial downvote reversal". The downvotes and the bonus show up on different days. Since a whole day's quota worth of downvotes equates to quite a fraction of my daily rep cap, what happens in the following circumstances?   I get 200+ rep on a particular day, but I am serial downvoted (later reversed) back to under 200. Does this day count as reaching cap? I get 200+ rep the next day, and I am also credited back the rep. Is the rep bonus immune to the rep cap in the same way bounties are? On the day I get my rep bonus, it is enough to take me to 200 rep. Does this count as capping? Say I am logged into a remote system, how can I know what it's running? On most modern Linuxes (Linuces?), you have the lsb_release command:  $ lsb_release -ic     Distributor ID: LinuxMint Codename:       debian   Which as far as I can tell just gives the same info as /etc/lsb-release. What if that file is not present? I seem to recall that the lsb_release command is relatively new so what if I have to get the OS of an older system?  In any case, lsb stands for Linux Standard Base so I am assuming it won't work on non-Linux Unices. As far as I know, there is no way of getting this information from uname so how can I get this on systems that do not use lsb_release? Localization of a UFD that is a PID Converting mxd to earlier version using ArcPy? As an extension to  on equiangular fisheye distortion, how can I calculate equidistant points around an ellipse (or 1/4 segment of) given it's aspect ratio? When it's circular, I can use a simple angle increment around the central point, but as the aspect ratio gets smaller, the length of the arc gets shorter and the angles are no longer equidistant. Why taking components of a component of a vector is invalid? Was PreferenceFragment intentionally excluded from the compatibility package? Linear regression with non-symmetric cost function? I want to predict some value $Y(x)$ and I am trying to get some prediction $\hat Y(x)$ that optimizes between being as low as possible, but still being larger than $Y(x)$. In other words: $$\text{cost}\left\{ Y(x) \gtrsim \hat Y(x) \right\}  &gt;&gt; \text{cost}\left\{ \hat Y(x) \gtrsim Y(x) \right\}  $$  I think a simple linear regression should do totally fine. So I somewhat know how to implement this manually, but I guess I'm not the first one with this kind of problem. Are there any packages/libraries (preferably python) out there doing what I want to do? What's the keyword I need to look for?  What if I knew a function $Y_0(x) &gt; 0$ where $Y(x) &gt; Y_0(x)$. What's the best way to implement these restrictions? Calculate line distances inside of polygons using ArcGIS for Desktop? I'm working with two data sets:   NHD polyline stream layer for my entire state HUC Watershed boundary Polygons for the entire state   I am looking for a way to calculate the total length of streams within each watershed boundary polygon, and would ideally like to have each polygon then attributed with the sum of stream miles within its boundary.  Can anyone help me? MWE:  \documentclass[a4paper,12pt,twoside]{memoir} \usepackage{DejaVuSerifCondensed} \usepackage[T1]{fontenc} \begin{document} \noindent\scshape{Hello World}\\ \textsc{Hello World} \end{document}   Explanation and question:  As you can see, I am working with a memoir document class and I've load a font DejaVuSerifCondensed, I am trying to obtain small caps for my header (which I did not place in the MWE as unnecessary). However I can't obtain the desire effect with the \scshape command nor with the \textsc{}.  I've seen other questions like     .   But either they do not adapt to my problem (for what I can see) or they do not solve the problem (following the instructions there and "inserting" the piece of code in mine).  Question here is: is there a general method (piece of code or something) to obtain small caps from a custom font (even if that is one I upload with a ttf)?, if not, what would be the piece of code to select the standard small caps font? I'm positive that vs I strongly believe that In general, which one is conveys a stronger conviction/opinion? I did some quick google search but didn't find any interesting results.      I'm positive that   or     I strongly believe that How can I disable my internet connection from terminal? Windows 10: Pin an item to left side of Start Menu? How can I select first occurrence between two patterns including them. Preferably using sed or awk.  I have:  text something P1 something content1 content2 something P2 something text something P1 something content3 content4 something P2 something text   I want the first occurrence of the lines between P1 and P2 (including P1 line and P2 line):  something P1 something content1 content2 something P2 something