cannot install ffmpeg - Unable to correct problems, you have held broken packages I want to install ffmpeg but get the message below. How can I fix this ?  (base) h@cheemc52:~/opencv/build$ sudo apt-get install ffmpeg 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:  ffmpeg : Depends: libavcodec56 (&gt;= 10:2.6.9) but it is not going to be installed           Depends: libavdevice56 (&gt;= 10:2.6.9) but it is not going to be installed           Depends: libavfilter5 (&gt;= 10:2.6.9) but it is not going to be installed           Depends: libavformat56 (&gt;= 10:2.6.9) but it is not going to be installed E: Unable to correct problems, you have held broken packages.   I am using Ubuntu 16.04  How do I know which is the correct solution ?  Solution 1  (base) h@cheemc52:~$ sudo aptitude install ffmpeg  The following NEW packages will be installed:   ffmpeg libaacplus2{a} libass5{a} libavcodec56{ab} libavdevice56{a} libavfilter5{a} libavformat56{ab} libavresample2{a} libfaac0{a} libfdk-aac1{a}   libpostproc53{a} libswresample1{a} libutvideo15{a} libvidstab1.0{a} libvo-aacenc0{a} libvo-amrwbenc0{a} libx264-146{a} libx265-51{a} 0 packages upgraded, 18 newly installed, 0 to remove and 74 not upgraded. Need to get 8,543 kB of archives. After unpacking 23.1 MB will be used. The following packages have unmet dependencies:  libavformat56 : Depends: libgnutls-deb0-28 (&gt;= 3.3.0) which is a virtual package and is not provided by any available package.   libavcodec56 : Depends: libvpx1 (&gt;= 1.3.0) which is a virtual package and is not provided by any available package.  The following actions will resolve these dependencies:       Keep the following packages at their current version: 1)     ffmpeg [Not Installed] 2)     libavcodec56 [Not Installed] 3)     libavdevice56 [Not Installed] 4)     libavfilter5 [Not Installed] 5)     libavformat56 [Not Installed]    Accept this solution? [Y/n/q/?]   Solution 2. All other solutions look similar to 2.  The following actions will resolve these dependencies:        Install the following packages: 1)      ffmpeg [7:2.8.15-0ubuntu0.16.04.1 (xenial-security, xenial-updates)] 2)      libavdevice-ffmpeg56 [7:2.8.15-0ubuntu0.16.04.1 (xenial-security, xenial-updates)] 3)      libavfilter-ffmpeg5 [7:2.8.15-0ubuntu0.16.04.1 (xenial-security, xenial-updates)] 4)      libbs2b0 [3.1.0+dfsg-2.2 (xenial)] 5)      libflite1 [2.0.0-release-1 (xenial)] 6)      libopenal-data [1:1.16.0-3 (now, xenial)] 7)      libopenal1 [1:1.16.0-3 (now, xenial)] 8)      libpostproc-ffmpeg53 [7:2.8.15-0ubuntu0.16.04.1 (xenial-security, xenial-updates)]        Keep the following packages at their current version: 9)      libavcodec56 [Not Installed] 10)     libavdevice56 [Not Installed] 11)     libavfilter5 [Not Installed] 12)     libavformat56 [Not Installed]    Accept this solution? [Y/n/q/?] q
Unable to correct problems, you have held broken packages After upgrading from 10.04 to 12.04 I am trying to install different packages.  For instance ia32-libs and skype (4.0).  When trying to install these, I am getting the 'Unable to correct problems, you have held broken packages' error message.   Output of commands:  sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.   After running this:  sudo dpkg --configure -a foo@foo:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Let $\Omega$ be an open subset in $\mathbb{C}$. Let $\{f_n\}$ be a sequence of holomorphic functions on $\Omega$ such that $f_n\to f$ pointwise and converges uniformly on any compact subset $K\subseteq \Omega$. Then by Cauchy Theorem and Morera Theorem, $f$ is holomorphic. Let $f_n$ and $f'$ be the derivatives of $f_n$ and $f$ respectively. Prove that $f_n'\to f'$ uniformly on any compact subset $K\subseteq \Omega$.   How to prove? Many people want to try/use Android without buying a new Android phone.  How can I install Android on my current phone or device running Nokia Symbian, Maemo, or MeeGo; Microsoft Windows Mobile or Windows Phone 7/8/10; Apple iOS (iPhone); RIM's BlackBerry OS; Palm's WebOS; Samsung's Bada; HP's WebOS; Mozilla's Firefox OS; or other phone / operating system? Now that I have Google Chrome all set up, I got myself a new laptop. Does anyone have any idea how to transfer my settings, cookies, favorites, etc?   I checked documents and settings\me\application data, and found nothing. How should artwork be setup for T-shirt printing? What does it mean to colour separate the artwork for T-Shirt printing? It is normally suggested to use Pantone colours for T-Shirt printing. Is it the Pantone Coated or the Pantone Uncoated? The Uncoated one has more subtle colours and we can't choose brighter shades if the design requires that. What is more appropriate for printing? Can we use gradients in T-Shirt printing or is it suggested to stick to flat colours only?   The reason for asking if gradients were ok was to use it as an option for this design:    I was considering it an option, as it will be difficult to colour separate since the textures are clip masked inside the lion. PHP mail function doesn't complete sending of e-mail Create a virtual file that is actually a command Is there any way to create a virtual file, such that reading from the file actually reads from the stdout of a command; writing to the file is acually writing to the stdin of a command?  So far I have kludged this with an inotifywait on a file, which calls a command when the file is modified, taking it's input from the file and writing back to it.  I don't like that the inotifywait has to be constantly restarted though (and I have to ensure that it is always running). I only use this file perhaps twice a week. Edit record from site.com In site.com I have a page which iterates records of an object with data repeater.  I want to edit these records from this page ,but I didn't find anything to achieve this.  If there is any option to do this please help me to implement this.  Thanks Does time pass fastest in isolated, resting space? 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? How can I completely remove ecryptfs from my system and delete .Private? Few days back I have installed ecryptfs, created a private directory using it. Now my Ubuntu login became super slow. I have tried removing ecryptfs from Synaptic. I found It, it can not be deleted that way. Somewhere I have read about this command  ecryptfs-setup-private --undo   But this command displays a rather confusing list of commands on terminal. I don't want to mess up my installation, neither want to loose my administrator account.  Now my question is, how can I safely remove /home/user/Private (.Private) and remove ecryptfs encryption ? Formula for coordinates (lat, lon), azimuth and distance. I would like to know how to find a set of coordinates on a small circle some distance from another point.   For example, lets say A = (39.73, -104.98) #Denver  B = (39.83, -106.06) #point approximately 50 nautical miles away from A along the great circle track to C  C = (40.75, -111.88) #Salt Lake City, approximately 323 nautical miles away from A  How do I get the set of orange coordinates when I don't know the angle but I do know the cross track distance?  For concreteness, lets say the outer points near B have a cross track distance of +- 30 nautical miles and the inner points have a cross track of +- 15nm.  And the points near C have a cross track of +- 25 nm.  Also I have an initial bearing from A to C of -1.34 #radians Recent file in Macbook Air I am not a very techie girl. I used my brother's macbook air and saw some of his personal things which I should haven't. And I realised that he could see that in recents. How to delete them? After surfing a lot, I got to know about the recent files stored in plist in preferences, by the name com.apple.recentfiles.plist or LSSharedfiles.plist but I couldn't find a file/plist named above. Kindly help! As mentioned above it is macbook air and again I do not know much :( Showing that $\sum_{i=1}^n \frac{1}{i} \geq \log{n}$ Can we get some consensus on what flag to use for link only answers? Related:  (not a dupe, that's a feature request and was closed as a dupe of another one)        (old) post does indeed say that Link-only answers can be flagged as NAA, but there are a lot of posts like  which define Not An Answer is a way that it doesn't apply to link-only answers.  Can we get some up-to-date consensus on this? That link only answers are not allowed is . Anyone know a simple method to swap the background color of a webpage using JavaScript? How can I center a too wide table? verifying an incorrect integrating factor I was doing some practice problems that my professor had sent us and I have not been able to figure out one of them. The given equation is:  $-y^2dx +x^2dy = 0$  He then asks us to verify that:  $ u(x, y) = \frac{1}{(x-y)^2}$  is an integrating factor.   I multiplied through to get:  $\frac{-y^2}{(x-y)^2}dx + \frac{x^2}{(x-y)^2}dy = 0$   However, the partial derivatives of these do not equal each other so I am a bit confused... Difference in sentence meaning between present continuous and simple present constructions Which external Javascript libraries work with Lightning Locker Service? Components often seem to work with external libraries until the Locker Service is enabled. What libraries work with locker service enabled and where can I go to find out? The qtree package seems to facilitate the drawing of simple trees only. Is there a way to incorporate:   Multiple roots &amp; Nodes with multiple parents   in a tree in LaTeX? Maintaining the final state at end of a CSS3 animation