The Ubuntu 13.04 32-bit desktop system requirements. What are they?
I'm thinking about installing Ubuntu Desktop, but I don't know what flavor is the best for my system. What are the minimum and recommended hardware requirements? What kind of CPU? How much memory? Should I have Hardware Acceleration? What flavor should I use?  This is an attempt of a canonical answer. My answers have the &quot;official  requirements&quot;, the recommended are a mix of official sources and opinion based (along with the answer it's told the source). You can comment or edit if you feel that the information is obsolete or incomplete. It is a good rule of thumb that any system capable of running Windows Vista, 7, 8, x86 (Intel) OS X will almost always be a lot faster with any Ubuntu flavor even if they are lower-spec than described below.
pgfmathanglebetweenpoints always returns 90 In fact, I would like to ask more general question -- &quot;what does write permission for a directory allow you to do exactly?&quot; -- but let's approach it with a concrete example. It is a long question, if you are in a hurry read the bold -- it should cover the main part. Different sources (, , ) say something similar to the following on the directory permissions:  r, read -- reading of the directory's content (filenames inside) w, write -- changing the directory's attributes (e.g. modification time) and creating/renaming/removing entries inside x, search -- accessing files inside, you have access to the inode of the file, hence you can reach it's actual content  My problem is with the description of w. What directory's attributes does it give you access to? I cannot create/rename/remove a file inside a directory with only write permission: I make a directory (tdir/) and a file inside (afile), chmod -x-r tdir/, mv tdir/afile tdir/af, rm tdir/afile, touch tdir/newfile -- all fail with permission denial, unless I set x permission to the directory as well. And x alone doesn't give you the permission to create/rename/remove files inside the directory. In order to do that you need both x and w. But touch tdir does change the modification time of the directory with w only. I would rephrase the sources above this way for the compliance with the issue: a directory's r allows you to see the filenames inside, but no access to the actual file (to the inode); x gives you access to the inodes of the files (which means you can see their permissions and, according to it, have access to the contents), but you still cannot change anything in the directory; directory is actually some sort of a file and to change something in it you need the w permission. Thus, when you are changing something in the directory you need w permission. If your change requires inodes of the files in the directory -- you need x as well. It explains why you cannot remove a file inside a directory with w only: when removing a file you need to reduce the link count of the inode by 1 -- you need to know the inode -- thus you need x for the directory. But why do you need x for creating (you could ask the system to create a file without exposing the inode?) and renaming/moving the file (when you move a file you don't change it in any way, you only change the records inside the directories and their inode counts?)? Maybe it is just an implementation thing? I.e. indeed you don't need the inode for renaming/creating files -- you need only filenames and w permission; but inode and filename constitute one record in the directory; thus changing the filenames = changing the records = kind of accessing the inodes. And also what attributes do directories have besides modification time, permissions and files records? What else in the directory can you change with w only? Why can two (or more) electric field lines never cross? What Android emulators are available? I will like to know some of the android emulators that work really well with Ubuntu 11.10 and above. I want to try 'whatsapp' on Ubuntu through an android emulator. Thanks in advance image of polynomial map is not an algebraic set I am doing an exercise about algebraic geometry, where the exercise  tell us to provide example of the image of polynomial map $f:\mathbb{C}^{m}\rightarrow \mathbb{C}^{n}$ that is not an algebraic set. But I am thinking that the image of every polynomial is $\mathbb{C}$ thus every polynomial map is surjective. What have I misunderstand? What if 'kill -9' does not work? I have a process I can't kill with kill -9 &lt;pid&gt;. What's the problem in such a case, especially since I am the owner of that process. I thought nothing could evade that kill option. Do Hutts find humanoid females attractive, and if so why? Jabba the Hutt kept scantily clad humanoid slaves.  Jabba even tried to kiss Leia.  But IIRC Hutts are hermaphrodites and of course should by all biological reasoning not be attracted to creatures of a specific sex (don't recall sexy dudes hanging around) with radically different body design.  So do Hutts find humanoid females hot, and if so why?  Or do they just do this for status and to show off to the largely humanoid populations that surround them? In D&amp;D 4E as with many RPGs, characters have a fixed armour value or AC. When attacking, the attacker must roll a die to overcome the target's AC. In 4E offensive magic works the same way: the target has a fixed Fortitude/Reflex/Will defence determined by their stats, and in order to hit, the attacker rolls to overcome whichever defence is relevant.   However it was not always like this. Some spells in 3E and now again in 5E work the opposite way. In those editions the target is the one who rolls against a fixed value determined by the caster's stats, in order to avoid spell-damage.  Both methods compare the attacker and target's stats, and have an element of randomness. I personally like the 4E system as it simplifies combat without leaving anything out. Why was the decision made, when designing the early D&amp;D editions (and still when iterating upwards into (A)D&amp;D 1e&ndash;3e), to use saving throws to control spells?  Answers should consist of designer quotes and not personal opinions. Issue in using longtable within table environment I have an issue making a long list with wrapped text. The table can be several page long. I use longtable and assign the width for each column but as soon as I put it in the \begin{table} \end{table}, it does not work. It clips the table. I want to make a label for the table so I put it in the table environment.  And is there a way to automatically adjust the width so that I don't need to assign the value manually?  Thank you.   Tung  \begin{table} \centering \begin{longtable}{|p{6.5cm}|p{2.5cm}|p{2.5cm}|p{2.5cm}|} \hline Name                                      &amp; Company     &amp;  Catalog Number   &amp;   Comments    \\ \hline Small DNA FRAG Extract Kit-100PR          &amp; VWR         &amp;   97060-558 &amp; \\ \hline Acrylamide 40\% solution 500 mL           &amp; VWR         &amp;   97064-522 &amp;  \\ \hline Bis-acrylamide 2\% (w/v) solution 500 mL  &amp; VWR         &amp;   97063-948 &amp;  \\ \hline GeneRuler 100 bp DNA Ladder, 100-1,000 bp &amp; Fermentas   &amp;   SM0241  &amp;    \\ \hline Mini Vertical PAGE System                 &amp; VWR         &amp;   89032-300  &amp;  \\ \hline \end{longtable} \label{tab:list} \end{table} Accelerating electrons via microwaves In Synchrotrons I think they use microwaves to accelerate the electrons bundles that fly through-how does putting a microwave through a cavity accelerate an electron? I know that the Electric and Magnetic fields could and do have an effect on the electron, but if the radiation is moving parallel to the electron, wouldn't the force be perpendicular? Also, how exactly does the microwave radiation look in the vacuum chamber? Are the two ends constant nodes? find all $(x,y,z)$ such that $27^{3x^2 + 2y}+27^{3y^2 + 2z}+27^{3z^2 + 2x}=1$ Find all ($x,y,z$) such that $$ 27^{3x^2 + 2y}+27^{3y^2 + 2z}+27^{3z^2 + 2x}=1$$  I am a high school student and would appreciate it if anyone could solve it using high school mathematics. here is what I have tried till now: $$ 3x^2 +2y &lt; 0 $$ (this can also be said for the other 3 equation. it also means that x,y,z&lt;0) $$ -2y&gt;3x^2 $$ $$ 4y^2&gt;9x^2 $$ ( -2y and 3x^2 are both positive) $$ 3y^2&gt;27/4 x^2 $$ $$ -2z&gt;3y^2&gt;27/4 x^4 $$ $$ 4z^2 &gt; 729/16 x^8 $$ $$ 3z^2&gt; 2187/64 x^8 $$ $$ -128/2187&lt;x^7 $$ $$ -2/3 &lt; x $$ $$ -2/3&lt; x,y,z &lt; 0 $$ i tried this but as you can see didn't do much good An annulus in $\mathbb R^2$ is path connected Let $A = \{(x,y) \in\mathbb{R}^2: a \leq (x-c)^2+(y-d)^2 \leq b\}$ for given $a,b,c, d$ real numbers. I want to show that $A$ is path-connected.  How can I do that?  I know that every open subset of $\mathbb R^2$ that is connected is path connected. But this is obviously not open so I cannot use that. Then I thought of multiple cases. If we take arbitrary $x$ and $y$ and draw the line between them and they do not intersect with the circle centred at $(c,d)$ then we can obviously draw a line between the points which is still in the set, so we can then define the function. I am stuck on the other case. How is unattended-upgrades started and how can I modify its schedule? I'm wondering who starts unattended-upgrades in my debian-jessie:   my man page   DESCRIPTION    This program can download and install security  upgrades  automatically    and  unattended,  taking care to only install packages from the config‐    ured APT source, and checking for dpkg prompts about configuration file    changes. All output is logged to /var/log/unattended-upgrades.log.    This  script  is  the backend for the APT::Periodic::Unattended-Upgrade    option and designed to be run from cron (e.g. via /etc/cron.daily/apt).  But my crontab doesn't show anything by crontab command:  @stefano:/etc/cron.daily$ crontab -l no crontab for stefano # crontab -l no crontab for root  But my unattended-upgrade work fine!(my unattended-upgrades log file) :  2017-02-05 12:42:42,835 INFO Initial blacklisted packages:  2017-02-05 12:42:42,866 INFO Initial whitelisted packages:  2017-02-05 12:42:42,868 INFO Starting unattended upgrades script 2017-02-05 12:42:42,870 INFO Allowed origins are: ['o=Debian,n=jessie', 'o=Debian,n=jessie-updates', 'o=Debian,n=jessie-backports', 'origin=Debian,codename=jessie,label=Debian-Security'] 2017-02-05 12:43:15,848 INFO No packages found that can be upgraded unattended   Where do I have to check/modify if I want to change my schedule? ArrayList object sorting confusion Is there an image editor like Windows' Paint for OS X? I tried out several image editors mentioned on  but some of them (like  and ) were very disappointing. These apps were too simple and low level.  What do you suggest for a (preferably free) image editor on OS X?  P.S: I was using  on Linux and also know that it was released for OS X too, but I want to find new good applications. Adjectives or compound noun? Calculation of $\lim_{n\to \infty}\prod_{r=1}^{n} \left(1+\frac{r}{n}\right)^{\frac{1}{n}}$ ArrayList vs List I saw this reply from Jon on :     If you want a single collection to   contain multiple unrelated types of   values, however, you will have to use   List&lt;object&gt;   I'm not comparing ArrayList vs List&lt;&gt;, but ArrayList vs List&lt;object&gt;, as both will be exposing elements of type object. What would be the benefit of using either one in this case?  EDIT: It's no concern for type safety here, since both class is exposing object as its item. One still needs to cast from object to the desired type. I'm more interested in anything other than type safety.  EDIT: Thanks Marc Gravell and Sean for the answer. Sorry, I can only pick 1 as answer, so I'll up vote both. Can I transfer saved data from my old PS3 hard drive to my new PS3? A while ago, my PS3 completely broke. Every time I turn it on, it just completely shuts down a few seconds later. I decided to buy a new ps3 to play my old games. The problem is that I don't have my saved data, but I still have the original hard drive. Is it possible to somehow transfer the saved data from the old hard drive to my new PS3? I was thinking maybe I could clone the hard drive, but I don't have a spare hard drive to do it on. I do however have a 2 TB external hard drive. Would it be possible to clone it on the external? Are there any alternative methods? Do we still need to avoid using frames and iframes for SEO? I thought frame and iframe were bad for SEO, but today I was doing a search for "numismatica" on Google.it.  The 3rd site is lemonete.com which is all made with frames. A competitor site (nummus.com) that has no frames ranks much lower when searching for the same word: "numismatica".  So can we use frames without taking an SEO hit now?  Any explanation (possibly simple) would be appreciated also about the fact the 2nd site ranks much lower. :)