Why doesn't "Software Updater" update all software?
Why Does Software Updater Say No updates Available, but apt-get upgrade Shows updates available?
Consider a horizontal surface with or without friction. Ideally, will a wheel rolling without slipping roll forever in both cases? Suppose a wheel is rolling smoothly on a horizontal plane i.e., it is rolling without slipping.  Now let's take the two cases of the horizontal plane:   It has friction It is frictionless   In the first case, as of my knowledge friction doesn't come into play when there is no slipping. So, will the wheel roll forever? If it comes to rest is the answer friction? If not what brings it to rest?  In the second case, there is no friction. So, here also will the wheel roll forever? And if it comes to rest what brings it to rest? How can I get textures on edge of walls like in Super Metroid and Aquaria? Games like Super Metroid and Aquaria present the terrain with the other facing parts having rocks and stuff while deeper behind them (i.e. underground) there's different detail or just black.      I would like to do something similar using polygons. Terrain is created in my current level as a set of overlapping square boxes. I'm not sure if this rendering method will work such a system for creating terrain but if anyone has ideas I'd love to hear them. Otherwise I'd like to know how I should re-write the terrain rendering system so it actually works to draw terrain in this manner... My website is javatechig.com and is around 6 months old. I have used All-in-One SEO WordPress plugin for SEO tricks. Definitely after using SEO plugin, my website page view is increased, but still it is not giving one good site-link in Google Search.   I have followed the following steps:   Created sitemap.xml and submitted to Google Webmaster Tools Edited all posts with meta tags Header tags are carefully taken care   I want to make a sitelink similar to the attached image: Secure hash and salt for PHP passwords No matter what I do I'm stuck with &gt;. How can I enter a new command?  $ chmod -R 600 `/ .ssh &gt;  &gt; chmod &gt; id_rsa.pub &gt;  &gt; sudo chmod 600 ~/ssh/id_rsa     I was trying to sync the master and slave by following a youtube video when I encountered the "permission denied" issue. While trying to resolve it I got stuck with &gt;. Now I can't enter any new command.   Please guide me. I'm a Linux/AWS newbie. Another simple series convergence question: $\sum\limits_{n=3}^\infty \frac1{n (\ln n)\ln(\ln n)}$ I'm being asked to determine if $\displaystyle\sum\limits_{n=3}^\infty \frac1{n (\ln n)\ln(\ln n)}$ converges. So, using Cauchy's Condensation Test, I reduced the problem to one of determining the convergence of $\displaystyle\sum\limits_{n=3}^\infty\frac 1{n\ln (n\ln 2)}$. Am I on the right path, and how do I proceed from here? Is there an SE for Cell-phones? Where would I ask a question pertaining to an ordinary phone? Or just cell phones in general? I saw Windows Phone while browsing the SE database, nothing else really popped out at me. Google didn't bring up anything either. Is that just too small a community to cover with SE? An electron has no known internal structure, does that imply it has an unknown one? I'm currently reading Alonso and Finn's Electromagnetism book.  It explains that the spin contributes to the magnetic moment and is somewhat comparable to a rotation of the particle around its own axis. It says that the spin of a particle is caused by a certain internal structure, which makes sense in the aforementioned analogy.  Right underneath the paragraph with the explanation of spin, it says "The electron has no known internal structure", but since it does have a spin, does that mean that we know the electron has an internal structure but we just don't know what it is? I have looked through several questions and answers on EL&amp;U, and often there is an indication that American English prefers "have" while British English prefers "have got". In addition, there are several references to "have got" being more informal than "have" (e.g.: , ). But where is it considered more informal? In American English alone or both American and British English?   This point may seem obvious to those who made the above mentioned references, but the fact is that even the most fluent users of English in my country will say without a doubt that 'have got' is the preferred usage in the UK and, therefore, it must also be more formal. Why? Because in an academic environment, the more informal structures are generally frowned upon, outside some specific spoken exercises. And if the teachers insist on using "have got", it follows it isn't informal.  So, is the teaching of (British) English in our schools transmitting the wrong idea?  EDIT: I'm adding some information in answer to the comments.  I'm mainly concerned with the idea of possession:      I have got a cat vs. I have a cat and She has got a dog vs. She has a dog   As mentioned in the comments, every (Portuguese) student will be told that "have" and "have got", when it comes to the idea of possession, are absolute synonyms, the only two differences being:    "have got" is preferred by British English, "have" is preferred by American English   the negative and interrogative structures differ    I have never heard of any distinction in formality. In fact, I was rather surprised when I went through the EL&amp;U archives and read about it.  So, would "I have got a cat" be as formal/informal as "I have a cat"?   And how do British and American English look at its formality/informality? Is it the same? Posts flagged for attention but there are none The comment with the Flagged Posts that seems to be new as of today states there are posts with flags awaiting my attention but the counter shows zero and when I go into flagged posts there is nothing waiting for me. Problems after upgrading to 14.04 (only background and pointer after login) How do you compile OpenSSL for x64? After following the instructions in INSTALL.W64 I have two problems:   The code is still written to the "out32" folder. I need to be able to link to both 32-bit and 64-bit versions of the library on my workstation, so I don't want the 64-bit versions to clobber the 32-bit libs. The output is still 32-bit! This means that I get "unresolved external symbol" errors when trying to link to the libraries from an x64 app. Is there any connection between a matrix being invertible and being diagonalizable? Let $A$ be an $n\times n$ matrix.  If $A$ is invertible then one of it's eigenvalues is 0.  If $A$ is diagonalizable then it has $n$ linearly independent eigenvectors.   Are these two statements true? Is there any connection between them? May I infer one from the other? Irrationality of $\sum_{p\in\mathbb{P}} \frac{1}{2^{p}}$ Let $\mathbb{P}$ be the set of prime numbers, and consider $m=\displaystyle\sum_{p\in\mathbb{P}} \frac{1}{2^{p}}$. Is $m$ irrational?  In the following  , the author recalls several sufficient criteria for irrationality. When applying some of this criteria to $m$ I arrive that the condition of some of the criteria are not satisfied by means of Bertrand´s Postulate.  I found a similar result by Sándor:  Let $\lbrace a_m\rbrace$, $m\geq 1$ be a sequence of positive integers such that $$\text{lim sup}\frac{a_{m+1}}{a_1a_2\cdots a_m}=\infty \;\;\;\;\text{and}\;\;\;\;\;\;\text{lim inf}\frac{a_{m+1}}{a_m}&gt;1$$ Then the series $\displaystyle\sum_{m} \frac{1}{a_m}$ is an irrational number.  I have yet to prove that if $f$ is a continuous function then $\text{lim sup} \;f(a_m)=f(\text{lim sup}\, a_m)$. Assuming this;  $$\text{lim inf}\; P_{m+1}-P_{m}&gt;1$$ where $P_m$ is the $m$-th prime.  But I have trouble with $$\text{lim sup}\; P_{m+1}-\sum_{j=1}^{m}P_{j}$$ my guess is that $$\text{lim sup}\; P_{m+1}-\sum_{j=1}^{m}P_{j}\neq\infty$$ so $$\text{lim sup}\frac{2^{P_{m+1}}}{2^{P_1}\cdots 2^{P_m}}\neq\infty$$   and this theorem will result useless to tell if $m$ is irrational.   How can I prove (or disprove) that $m$ is irrational (are there any other simpler criteria)? How can I use Dirichlet criterion  or Hurwitz criterion? What is its ?    Any help is highly appreciated.      Edit: That $m$ is irrational is clear by the criteria provided in the comments, namely that if $x$ is rational then the binary representation of $x$ is periodic. The number $m$ in binary expansion has $1$ in the $P$-th position and zero elsewhere. As there are arbitrarily large gaps between primes; then the binary representation fails to be periodic.  So the question that remains unsolved is:   What is its irrationality measure? This is my code:  import datetime today = datetime.date.today() print(today)   This prints: 2008-11-22 which is exactly what I want.  But, I have a list I'm appending this to and then suddenly everything goes "wonky". Here is the code:  import datetime mylist = [] today = datetime.date.today() mylist.append(today) print(mylist)   This prints the following:   [datetime.date(2008, 11, 22)]   How can I get just a simple date like 2008-11-22? I am trying to assign an image texture to an Image Texture node in 2.80. Very simple script - I'm just starting to learn how this stuff works.  This is what I have. It creates an image and and IT node, but it doesn't assign the one to other. Can anybody help? I've searched around, but can't find it in another question.  import bpy  #create blank image bpy.ops.image.new(name="TestImg", width=1024, height=1024)  #add image texture to object, to hold baked lighting mat = bpy.context.view_layer.objects.active.active_material image_node = mat.node_tree.nodes.new('ShaderNodeTexImage')  #assign image to image texture node image_node.image = "TestImg"   Thanks in advance. Could not find class Prove that $\sum^{n}_{r=0}(-1)^r\cdot \large\frac{\binom{n}{r}}{\binom{r+3}{r}} = \frac{3!}{2(n+3)}$ My girlfriend forgot the password for her MacBook (don't ask), so I reset it using the Utilities.  But as you may be aware, this doesn't reset the Keychain password. Her MacBook is now virtually unusable due to Keychain demands continuously provoking a request for the Keychain password.  There are lots of other people asking this around the web and they're usually pointed towards this , which doesn't apply in our situation because the support advice involves entering the old password.  We don't know the old password.  Is it possible to reset Keychain without knowing the old password? We're not bothered about what's in there and what will be lost, we just want the continuous password prompts to go away. I'm wondering where a new path has to be added to the PATH environment variable. I know this can be accomplished by editing .bashrc (for example), but it's not clear how to do this.  This way:  export PATH=~/opt/bin:$PATH   or this?    export PATH=$PATH:~/opt/bin