I'm new in linux. Trying to remove libreoffice from by xubuntu 20.04. Libreoffice was installed with xubuntu. I execute many variants: sudo apt remove 'libreoffice\*' sudo apt remove 'libreoffice*' sudo apt remove 'libreoffice.*'  In all cases I got error: E: Unable to locate package libreoffice.*  &lt;result depends on input&gt;  What I tried: but next solution shows how use apt-get instead of apt.  My questions are:  how to specify mask for apt remove command? how to remove correctly libreoffice using apt? what if I use apt-get for this case?
When I run this command :  apt install libkf5*   I get the following error :  Unable to locate package libkf5*    I'm sure that the packages whose names start with libkf5 exist (tab-completion says so) . So the problem is not about the absence of those packages.(Note the asterisk at the end of that error message , the wildcard's not working at all) I use apt v.1.9. Thanks in advance.
I have an independent variable called "quality"; this variable has 3 modalities of response (bad quality; medium quality; high quality). I want to introduce this independent variable into my multiple linear regression. When I have a binary independent variable (dummy variable, I can code 0 / 1) it is easy to introduce it into a multiple linear regression model.  But with 3 modalities of response, I have tried to code this variable like this :  Bad quality      Medium quality      High quality       0                1                  0      1                0                  0      0                0                  1      0                1                  0   But there is a problem when I try to do my multiple linear regression: the modality Medium quality gives me NA:    Coefficients: (1 not defined because of singularities)    How can I code this variable "quality" with 3 modalities? Do I have to create a variable as a factor (factor in R) but then can I introduce this factor in a multiple linear regression? How do I remove hidden backup files? I have files ending in ~ in my home directory, and I want to delete them. How do I do that? How do I prevent this backup functionality? A Particular Two-Variable System in a Group Suppose $a$ and $b$ are elements of a group $G$. If $a^{-1}b^{2}a=b^{3}$ and $b^{-1}a^{2}b=a^{3}$, prove $a=e=b$.   I've been trying to prove but still inconclusive. Please prove to me.  Thanks very much for proof. Ubuntu doesn't boot! Is it possible to legally visit uninhabited islands in the Pacific for a couple of days/weeks like Robinson Crusoe Do you know any way how can I visit uninhabited islands in the Pacific (French Polynesia, Micronesia etc.) and stay there for a couple of days or weeks?  The only condition, these island (or islands) should have drinking water.  Could it be done legally or only illegally?  Does any company do such crazy things via plane or boat?  Any information is appreciated.  I am mostly interested in French Polynesia.  Boat or plane... that's not very important. My machine was updated today to Ubuntu 16.04.2. However, the kernel is still "4.4.0-62-generic". What happened (it seemed that the principal advantage of the 16.04.2 version was the update of the kernel to 4.8) ? Do I have to make a fresh install ? Series of books featuring dragons, enchanted forests, magic swords, etc When I was younger I read a series of 3 or 4 books involving largely traditional mages/dragons/enchanted forests.  I'd like to buy it for some of my younger extended family members but I can't remember the name of it.  Here's what I remember from this:   I read the last book first, in which the son of a woman turned out to be largely one of the main characters in the other books takes an enchanted sword into a forest on a quest to do something. At one point in one of the earlier books the group was travelling through a swamp like area to get to a tower where a witch(or mage lived). There was a king (possibly the son's father) who was frozen in a castle during the last book. The evil mages/witches would melt (but not die) when some spell was cast on them. I read the series circa 1992 (estimated), comparable to the DragonLance series it was geared towards a younger audience (I don't remember any sex/brutal slayings of anyone). I believe in the first book the mother of the son in the last book runs away from home and becomes something of a maid to a dragon. I can't remember if there were evil dragons or not, I seem to remember that at least some of them were good (or at least largely neutral).   If I think of any other details I'll add them. Gaussian integral evaluation Asked a question to evaluate the Gaussian Integral,  $$\dfrac{1}{\sqrt{2\pi}} \int_{-\infty}^\infty x^2 \exp(-x^2/2) dx  $$  using the the following approximation,  $J=\Bbb E[X^2] \sim J_N = 1/N \sum_1^NX_n^2 $  where $x_n \sim N(0, 1)$  Examin $J_N$ for different values of $N$ and plot an error graph (difference between exact and numerical values)  I can simulate and generate the approximations but I am stuck at getting the exact value to compare to. As far as I am aware there are no analytical solutions for gaussian integrals. The other way I can generate comparable numbers is to go use numerical integration techniques but those are approximate values too.  Any help will be greatly appreciated! Related to the question :  It is well known that   $$\zeta(2n) = f(2n) \pi^{2n}$$  where $f(n)$ is an function in rationals: (the denominator = OEIS : 6, 90, 945, 9450).  Apery proved that $\zeta(3)$ is irrational, and presumably $f(2n+1)$ is so for all (but the latter is open).  But what else is known about $f(2n+1)$? What sort of pattern does it share (if any) with $f(2n)$? Numerically does it fit well? Is there any clue/progress since Apery as to its form? Of course, $f(2n+1)$ may in effect divide out the $\pi$, meaning that somehow $\pi$ is not involved in $\zeta(2n+1)$ in any essential way. For example, I can't install package qcad because of error: "can't find qdict.h". How can I find the package which provides the file qdict.h so I can install the package qcad? Update (March, 2012): This has been rolled out to all sites in the network.    Behind the scenes we've been hard at work making some changes to how we track reputation.  Here are some of the issues we're aiming to address with these changes:   Reputation Skew (your actual reputation doesn't match what's shown) Up/Down votes oddities (mostly with the daily rep cap, the magical +2) Historical Deletes (not impacting rep immediately, contributing to skew) Unaccepts (display issues in the profile) User Deletion (magically missing rep, another skew contributor)   To be clear: reputation values are not changing, every action in the system is still worth the same amount.   Here’s what will be different:   Your reputation will be correct at all times Deletions will have a much more immediate effect on reputation, not waiting on a recalc  (but reputation sync takes up to 5 minutes on a delete/undelete action; as to not block the user's response thread, it's offloaded to a background queue) Recalcs will no longer be necessary Up/Down vote reversals will restore the correct reputation amount Up/Down vote reversals will correctly adjust to the reputation cap The reputation history in your profile will be more detailed and accurate (e.g. when a post is deleted, you'll see that in the reputation tab of your profile)   This means your reputation will go up and down more than it has previously, but it will be in sync.  To think of it more easily: imagine that a recalc will be done after every action in the system.  Probably the biggest impact many will be concerned with is that you may see your reputation drop in cases where it didn't seem like it did before  This was effectively happening before, but the results of that change were not applied immediately, but on the next rep recalc.  Post deletion is the biggest factor here, previously it didn't (immediately) account for the reputation impact...that will no longer be the case.  Reputation changes from the deletion will now be applied within the hour, and most other changes will be instant.  Now the part that will make everyone throw vegetables our way:  this will require a global recalc to get everything in sync.  We'll be rolling it out first here on meta, then the rest of the network...the enabling of the detailed rep view and global recalc on each individual site will coincide.  During the rollout you will see empty reputation tabs on profiles as we transition to the new storage behind the scenes, they'll be restored as the recalc rolls though each user.  We’ll put up a blog post on  before the network-wide rollout.  If you have any questions about this change or details I may have left out, please do so in answers below so that we can clear up as much as possible before this rolls out. Quite a few of the questions given on this site mention a photon in vacuum having a rest frame such as it having a zero mass in its rest frame. I find this contradictory since photons must travel at the speed of light in all frames according to special relativity.  Does a photon in vacuum have a rest frame? How can I ensure testNG test method does not abort if any assert fails I know there is a difference between assert and verify in Junit; the assert results in a runtime exception, causing test method execution to abort. To overcome this problem, we can have verify which will make test case fail, but allowing test execution to proceed rather than getting aborted.  I doubt there is any such built in approach in testNG. I do understand that best practices say, there should not be multiple asserts in same test case.  But, in practical world, we do come across scenarios where we need to have multiple checkpoints in one test case and we don't want our test method to abort because of one check point failure (test execution should proceed despite failure).  How can we use a soft assert mechanism, similar to verify, which will not abort test method when there is a checkpoint failure.  Example:  @Test(dataProvider = "getMailUrl") public void testMail(email,subject); Assert.assertFalse(subject.isEmpty);//1st checkpoint Assert.assertNotNull(email); //2nd checkpoint Assert.assertEquals(email, "feedback@yoursite.com"); //3rd checkpoint   Now, I want test execution to proceed, even if the 1st checkpoint (validation of subject being not empty) fails. Definitely we will be not be using assert (hard assert). We will need concept of soft assert similar to verify (facilitated by Junit).   I understand, we have to build a customListener implementing TestNG interfaces or extending existing listeners such as TestListenerAdapter. I am still struggling - how can we do this? Where to get 2010 Census Block data? I would like to download 2010 Census Block Data for several towns and I can't seem to find it on American Factfinder.   Is it there? And if not, does anyone know where I could find it? How can I make an object show up on different layers What are the benefits of modeling in one piece, or as separate parts? Is there any benefit of creating model in one piece or I can create separate pieces and just overlap them to create a visually joint part.  For example, the below image were made from two parts 1. Blade 2. Spinner  Is there any benefit to model them (e.g. extrude from the spinner) or it is actually ok to have them separated since visually I can achieve the same effect (See picture 2) Idiom or expression that would imply "someone is a habitual liar" I'm looking for an idiom or expression for describing people who tell lies out of habit (so you cannot trust them at all).   I know that these people are called , but I'm not looking for psychological terms.  Is there any idiom or expression for describing such people?   For example:     "Did X tell that to you?! Come on, don't believe him/her. Don't you know he/she ___ (=is a habitual liar)?" How to get exact camera view? I'm currently a beginner when it comes to 3D modelling but doing okay so far. I'm struggling a bit when it comes to the final renders of my scene, specifically on the camera view I want. Sometimes its to zoomed in and sometimes to zoomed out that it's gone out of the environment of the blender. I realized the settings for the camera on blender are for actual cameras / photography and I'm no expert on that too. A tip on how to control them precisely would be nice. Thank you. I had to write the proof to show that an Ideal $P$ of a commutative ring $R$ is prime Ideal if $R/P$ is an integral domain.       let $a,b\in R$ s.t. $ab\in P$ ,        $$ab+P=P\implies(a+P)(b+P)=P\implies\overline a \overline b=0$$  and as $R/P$ is an integral domain either $a=0$ or $b=0$ $\implies a+P=P$ or  $b+P=P$.        $\therefore$ either $a\in P$ or $b\in P$.   Hence, $P$ is a prime Ideal.    Am I correct in writing this or am I making some error... I would like to look at my referral traffic over time on a per domain-basis in Google Analytics. This is what I have done:   Set New visits as advanced segment  Navigated to traffic-sources -> Referrals Checked a coulple of domains Clicked plot rows   The individual domains now show up in the graph, but the problem is that "all traffic" is also visible. All traffic is much bigger than the graphs for individual domains. This makes it very hard to see any changes as they look all values are Zero.  Is there any way to hide "Visists" from the graph in order to zoom in on the vertical axis?