I'm trying to remove codeblocks package as shown below, but it shows error like this. I've tried the following: sudo apt-get install -f sudo apt-get update sudo apt-get autoclean sudo apt-get clean sudo apt-get autoremove  On runningg sudo apt-get remove codeblocks, I see the following error: Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies:  codeblocks-contrib : Depends: libboost-system1.67.0 but it is not going to be installed                       Depends: libwxgtk3.0-0v5 (&gt;= 3.0.4+dfsg) but it is not installable                       Depends: libwxsmithlib0 (= 20.03) but 20.03-3 is to be installed                       Depends: codeblocks (= 20.03) but it is not going to be installed                       Recommends: valgrind but it is not going to be installed                       Recommends: cppcheck but it is not going to be installed                       Recommends: cscope but it is not going to be installed                       Recommends: cccc but it is not going to be installed  codeblocks-dev : Depends: libcodeblocks0 (= 20.03) but 20.03-3 is to be installed  codeblocks-libwxcontrib0 : Depends: libwxgtk3.0-0v5 (&gt;= 3.0.4+dfsg) but it is not installable E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).  I tried the sudo apt --fix-broken install command, which gives the following output: Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following package was automatically installed and is no longer required:   libllvm9 Use 'sudo apt autoremove' to remove it. The following additional packages will be installed:   codeblocks-contrib codeblocks-dev Recommended packages:   valgrind The following packages will be REMOVED:   codeblocks-libwxcontrib0 codeblocks-libwxcontrib0-dbgsym codeblocks-wxcontrib-dev codeblocks-wxcontrib-headers The following packages will be upgraded:   codeblocks-contrib codeblocks-dev 2 upgraded, 0 newly installed, 4 to remove and 33 not upgraded. 6 not fully installed or removed. Need to get 0 B/4.969 kB of archives. After this operation, 6.059 kB disk space will be freed. Do you want to continue? [Y/n] y (Reading database ... 190539 files and directories currently installed.) Preparing to unpack .../codeblocks-contrib_20.03-3_amd64.deb ... Unpacking codeblocks-contrib (20.03-3) over (20.03) ... dpkg: error processing archive /var/cache/apt/archives/codeblocks-contrib_20.03-3_amd64.deb (--unpack):  trying to overwrite '/usr/lib/codeblocks/wxContribItems/libwxchartctrl.so.0.0.1', which is also in package codeblocks-libwxcontrib0 20.03 dpkg-deb: error: paste subprocess was killed by signal (Broken pipe) Errors were encountered while processing:  /var/cache/apt/archives/codeblocks-contrib_20.03-3_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)  After this I am not able to install any package. How i can solve this problem?
Occasionally, when I'm installing stuff, I get an error like the following:  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:  package1 : Depends: package2 (&gt;= 1.8) but 1.7.5-1ubuntu1 is to be installed E: Unable to correct problems, you have held broken packages.   How can I resolve this?
I hope this qualifies as a programming question, as in any programming tutorial, you eventually come across 'foo' in the code examples. (yeah, right?)  what does 'foo' really mean?  If it is meant to mean nothing, when did it begin to be used so? I've heard that you need to get a Mac if you want to develop iPhone apps. Is this true?   Is it possible to develop iPhone apps using Linux? If yes, what do I need and where do I download the necessary tools? Modular Arithmetic - Find the Square Root How to change fonts I'm sure this is a newbie question, but I can't figure this out. I have tried to follow the advice here:  and here:   But I can not seem to be able to generate any font change. I either get no change or error messages.  Here is the output of one failed attempt to change the font to Times using this command:  \rmfamily \renewcommand{\rmdefault}{ptm}     Apparently I either don't have a correct package installed or...  The output says " Metric (TFM) file not found." but I am not sure where to go from there. Is Einstein's Special Relativity completely inclusive of Newton's 3 laws of motion? Relativity has always been explained to me (in books I've read, etc) as a superset of newton's laws - that is; it encapsulates all of Newton's mechanics in addition to other effects (observer effect, time dilation, space-time geometry, etc).   I can kind of imagine 2 of Newton's 3 laws of motion to be incapsulated within Einstein's Special Relativity, but the one about "for every action there is an equal and opposite reaction", I'm struggling to find a place for that within Special Relativity.   Does this sit outside Special Relativity's explanatory power or is it inferred within somehow? Intuition of pdf of a continuous random variable What is the intuition behind the probability density function of a continuous random variable? Integrating it within two points provides the probability that is associated between two points, but if you plug a single value into $f(X=x)$, it outputs a value. What is the intuitive understanding of this value for a given x?   For example, in the above image, the value of the red curve at x=0 is 0.4. How can 0.4 be interpreted? Is there a quasistatic process that is not reversible? I have seen several questions and good answers on the link between reversible and quasistatic processes, such as  or . However, these questions only adress one side of the problem : a reversible process is necessarily quasistatic.  I am interested in the other side of the equivalence : is there a process that is quasistatic, yet not reversible ? It looks to me that an irreversible process cannot be made perfectly quasistatic.  The  article about quasistatic processes takes as an example the very slow compression of a gas with friction. As the compression occurs very slowly, the transformation is quasistatic, and the friction makes it irreversible. I am not convinced by this example : if you press on the piston with a vanishingly small force you will have to reach the threshold of the Coulomb law for solid friction before moving the piston anyway. It makes the process non-quasi-static, however small the Coulomb threshold might be.  Another example I've heard of is the reaction between a strong acid and a strong base. It is always an irreversible process, and you could make it quasistatic by adding very small drops of base into acid at a time. But by trying to do that, you would inevitably reach a limit to the size of the drop imposed by surface tension.  Even if "reversible" and "quasistatic" mean very different things, is it true to consider that in practice, a reversible process and a quasistatic process is essentially the same thing ? Can the JVM recover from an OutOfMemoryError without a restart Database schema documentation for the public data dump and SEDE Stack Exchange releases "data dumps" of all its publicly available content roughly every three months , and also makes that information queryable over the Internet at the  (SEDE) (updated weekly, on Sunday). Over time, as new features and other bits of data are introduced to Stack Exchange sites, the "anatomy" of the data dump is likely to change. Why can't I chown a VirtualBox shared folder? How to evaluate $\int_{0}^{\pi }\theta \ln\tan\frac{\theta }{2} \, \mathrm{d}\theta$ For what longest possible time it was possible to hold light in a closed volume with mirrored walls?   I would be most interested for results with empty volume but results with solid-state volume may be also interesting. Probability of selecting an even natural number from the set $\Bbb N$. I confirmed on  thread that there are as many as even natural numbers as there are natural numbers.   Question : Suppose I have selected a number $n \in \mathbb N$; what is the probability that $n$ is even?  My Thought : $\text{Probability} = \dfrac{\text{n(E)}}{\text{n(S)}}$ Here $\text{n(S)}$ is the set of all natural numbers i.e. $\mathbb N$, and $\text{n(E)}$ is set of all even natural numbers. Since it is proved that number of elements is the set $\mathbb N$ is exactly the same as the number of elements in the set of natural numbers (it’s very easy to put the set of natural numbers, $\Bbb N=\{0,1,2,3,\dots\}$, into one-to-one correspondence with the set $\text{E}=\{0,2,4,6,\dots\}$ of even natural numbers; the map $\Bbb N\to \text{E}:n\mapsto 2n$ is clearly a bijection.) ; Thus, Probability $= \boxed 1$ I know this is definitely wrong.Probability must be $0.5$. But where am I wrong? Can anyone explain ? Thanks! I installed Opera 12.16 from a .deb for reasons. Just assume that I need this specific browser of this specific version and that there’s no alternative.  However, that deb depends on packages (such as the gstreamer0.10 series) which are not in my distribution anymore (Debian testing). This makes apt fail on every operation except apt remove opera with dependency errors:  # apt install cli-common Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies:  opera : Depends: gstreamer0.10-plugins-good but it is not installable          Recommends: flashplugin-nonfree but it is not going to be installed E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).   apt --fix-broken install will just propose to remove opera:  # apt --fix-broken install Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages will be REMOVED:   opera 0 upgraded, 0 newly installed, 1 to remove and 92 not upgraded. 1 not fully installed or removed. After this operation, 46.6 MB disk space will be freed. Do you want to continue? [Y/n]   Currently, my workaround is to install Opera when I need it, and remove it as soon as anything else needs to be done with apt. This is annoying.  Any suggestions? Ideally, I’d like to make apt ignore the dependencies of opera forever, since it works well-enough for my purposes. Randomly selecting elements without repetition Reference: Why are my "special" Unicode characters encoded weird using json_encode? Building a wormhole We regularly get questions about wormholes on this site. See for example  and . Various wormhole solutions are known, of which my favourite is  because it's closest to what every schoolboy (including myself many decades ago) thinks of as the archetypal wormhole.  The trouble is that Visser has pulled the same trick as  of starting with the required (local) geometry and working out what stress-energy tensor is required to create it. So Visser can tell us that if we arrange exotic string along the edges of a cube the spacetime geometry will locally look like a wormhole, but we know nothing about what two regions of spacetime are connected.  My question is this: suppose I construct a Visser wormhole by starting in Minkowksi spacetime with arbitrarily low densities of exotic matter and gradually assembling them into the edges of a cube, how would the spacetime curvature evolve as I did so?  I'm guessing that I would end up with something like Wheeler's bag of gold spacetime. So even though I would locally have something that looked like a wormhole it wouldn't lead anywhere interesting - just to the inside of the bag. I'm also guessing that my question has no answer because it's too hard to do any remotely rigorous calculation. Still, if anyone does know of such calculations or can point me to references I would be most interested. Can I play against or with Xbox 360 players through my Xbox One? Is it possible to play against and with Xbox 360 players through my Xbox One? I want to find the interval of convergence of $$\sum_{n=0}^\infty (\frac{n}{n+1})^{n^2}(2x)^n$$ By the root test, $\sqrt[n]{|(\frac{n}{n+1})^{n^2}(2x)^n|}=|(\frac{n}{n+1})^{n}(2x)|$  And $(\frac{n}{n+1})^n=(1-\frac{1}{n+1})^n\to\frac1e$ as $n\to\infty$  So I've got an open interval(of convergence) s.t. $|\frac1e 2x|&lt;1\implies |x|&lt;\frac e2$.  Now I need to figure out whether the series is convergent or not at the end points, $x=\frac e2, -\frac e2$.  So there are two series I need to deal with, namely, $\sum_{n=0}^\infty (\frac{n}{n+1})^{n^2}e^n$ and $\sum_{n=0}^\infty (\frac{n}{n+1})^{n^2}(-1)^ne^n$.  Suppose $(\frac{n}{n+1})^{n^2}$ is increasing. Then $$(\frac{n}{n+1})^{n^2}&lt;(\frac{n+1}{n+2})^{(n+1)^2}\iff 1&lt;(\frac{n+1}{n+2})^{(n+1)^2}(\frac{n+1}{n})^{n^2}$$ $$\iff 1&lt;(1-\frac{1}{n+2})^{2n+1}(1+\frac{1}{n^2+2n})^{n^2}$$  But $(1-\frac{1}{n+2})^{2n+1}\to\frac{1}{e^2}$ and $(1+\frac{1}{n^2+2n})^{n^2}&lt;(1+\frac{1}{n^2})^{n^2}\to e$  So I have $1&lt;\frac1e&lt;1$, which is a contradiction. Hence $(\frac{n}{n+1})^{n^2}$ is not increasing. But I don't know if it's decreasing. (is it true that $(1+\frac{1}{n^2+2n})^{n^2}\to e$?)  If $(1+\frac{1}{n^2+2n})^{n^2}\to e$ is true, then $(\frac{n}{n+1})^{n^2}e^n$ converges to some positive number, so $\sum(\frac{n}{n+1})^{n^2}e^n$ diverges. But I don't know if it's decreasing: can't apply the alternating series convergence test(Leibniz's criterion).  So, can you help me with the two end points? Firefox browser opens but URL is not launched