I would like help drawing a specific graph in LaTeX
I feel intimidated in learning TikZ. I was wondering if there are some nice materials (or just your replies) at different level:   for providing big picture, which is important to beginners to not lose direction during learning. for comprehensive reference.   Examples are important, but only examples are not always clear for understanding the big picture and organization.
How do I send a file as an email attachment using Linux command line? I've created a script that runs every night on my Linux server that uses mysqldump to back up each of my MySQL databases to .sql files and packages them together as a compressed .tar file.  The next step I want to accomplish is to send that tar file through email to a remote email server for safekeeping.  I've been able to send the raw script in the body an email by piping the backup text file to mailx like so:  $ cat mysqldbbackup.sql | mailx backup@email.com   cat echoes the backup file's text which is piped into the mailx program with the recipient's email address passed as an argument.  While this accomplishes what I need, I think it could be one step better, Is there any way, using shell scripts or otherwise, to send the compressed .tar file to an outgoing email message as an attachment?  This would beat having to deal with very long email messages which contain header data and often have word-wrapping issues etc. From official :     Due to a head injury, Cyclops is unable to shut off his optic blasts   at will and must therefore wear ruby quartz lenses to block the beams.   From the same page:     Cyclops possesses the mutant ability to project a beam of heatless   ruby-colored concussive force from his eyes, which act as   inter-dimensional apertures between this universe and another.   When his eyes are always blocked by ruby-colored beam of concussive force, how does he see? Easy is to beginner as medium is to I want to display three levels in my game...but I don't know what the text should say.  easy -&gt; Beginner  medium -&gt; ?  hard -&gt; Expert   Basically, I want the form that describes the person playing the game, instead of the game itself. What adjective is best?  I have considered adept.  I doubt my users will know what adept means. Also, I need something in between expert and beginner. Adept falls into the expert category. Is there anything more common that I can use, that has the same impact as the other two words I mentioned?  Proficient would work, theoretically, but in day-to-day term, the levels "beginner - proficient - expert" won't sound great. In C++, what is the purpose of the scope resolution operator when used without a scope? For instance:  ::foo(); How can I bind the meta key (a.k.a.  / Windows key) to a left click? Hitting the meta key should trigger a left click, and pressing down on it should allow me to drag and drop (just like it would do when holding down left click).  I tried using System Preferences -> Shortcuts and Gestures:    but I cannot set "meta" alone as being a shortcut.  I use Kubuntu 14.10 Plasma 4 and Kubuntu 14.04 LTS x64.   (On Windows 7 SP1 x64 Ultimate I can achieve that using the program .) Python argparse: default value or specified value Can principal component analysis be applied to datasets containing a mix of continuous and categorical variables? I have a dataset that has both continuous and categorical data. I am analyzing by using PCA and am wondering if it is fine to include the categorical variables as a part of the analysis. My understanding is that PCA can only be applied to continuous variables. Is that correct? If it cannot be used for categorical data, what alternatives exist for their analysis? Watch Filesystem in Real Time on OS X and Ubuntu I'm looking for a CLI tool which will watch a directory and spit out the names of files that change in real time.   some_watch_command /path/to/some/folder | xargs some_callback   I'm aware of inotify (inotify-tools?) and it seems to be what I need, but I need something that is both Linux (in my case Ubuntu) and OSX compatible.  It doesn't need to be lightning fast, but it does need to trigger upon changes (within a second is reasonable). Also, I don't necessarily need the exact CLI program mentioned above.  If some underlying tech exists and is easily scriptable on both platforms that would be great too. How do I animate time? Sort and count number of occurrence of lines I have Apache logfile, access.log, how to count number of line occurrence in that file? for example the result of cut -f 7 -d ' ' | cut -d '?' -f 1 | tr '[:upper:]' '[:lower:]' is  a.php b.php a.php c.php d.php b.php a.php   the result that I want is:  3 a.php 2 b.php 1 d.php # order doesn't matter 1 c.php What caused the oathbreakers in the Paths of the Dead to turn into shades? In Return of the King, we are told that the shades who populate the Paths of the Dead are the spirits of oathbreakers who refused to aid Isildur in the first fight against Sauron.  First, we are told of the oath (Book 5, Chapter 2):     But the oath that they broke was to fight against Sauron... For at Erech there stands a stands yet a stone that was brought, it is said, from Númenor by Isildur... and upon it the King of the Mountains swore allegiance to him in the beginning of the realm of Gondor.   Then, when they fail to honor the oath, we are told about Isildur's curse on them:     "...this curse I lay upon thee and thy folk: to rest never until your oath is fulfilled."   And as we see in the following chapters, the Sleepless Dead are indeed subject to this curse exactly as Isildur descibed it. What seems less clear, however, is how Isildur's curse manages to alter the fundamental nature of the oathbreakers' mortality, so that they became undead shades instead of simply dying in disgrace.   Do we have any other examples of Isildur performing similar acts of magic? Based on what we are told in LotR, Isildur appears to have been a great warrior, but not a regular practitioner of magic. Is the stone at Erech somehow magically involved? (If so, do we know anything more about it or how it works? Does its origin in Númenor have any significance?) It is mentioned that the oathbreakers had worshiped Sauron; could this be a clue? Show Capslock on Windows 8 HTML Element Array, name="something[]" or name="something"? Understanding relation between Quotient Space and $S^1$ There is this example at the Wikipedia article on Quotient spaces (QS):     Consider the set $X = \mathbb{R}$ of all real numbers with the ordinary topology, and write $x \sim y$ if and only if $x−y$ is an integer. Then the quotient space $X/\sim$ is homeomorphic to the unit circle $S^1$ via the homeomorphism which sends the equivalence class of $x$ to $\exp(2πix)$.   I understand relations, equivalence relation and equivalence class but quotient space is still too abstract for me. This seems like a simple enough example to begin with.  I understand (sort of) the definition but I can't visualize. And by this example and others, there is a lot of visualizing going on here! torus, circles etc. Clicking on tags in global search results is broken If you search for something on "all sites" (using the searchbox at the top of , you'll reach the search results, e.g.  .  If you click directly on a tag on that page, e.g.        You get 404 Page Not Found error, e.g.     Steps to reproduce   Go to  and enter e.g. "keyforge" into the "Search all sites" field. Arrive at  Click on the "keyforge" tag below a search entry. Reach  (404 page not found)   Expected behaviour  Reach   System Info  Happens in both Firefox and Vivaldi browsers on Windows 10. Array index out of bound behavior "Who wants ice-cream?" — Should I say "(not) I" or "(not) me"? Macbook Air - how to install a dual bootable Ubuntu 14.04 LTS On my Macbook Air 10.9.2 without crashing the current setup, how can i install as dual boot: Ubuntu 14.04 LTS ? (can anyone please advise some step by step please) Rotation Path Not Shown in Graph Editor I created a couple of LocRot keyframes but the rotation path and keyframes aren't shown in the graph editor (no, they aren't hidden). Differences between ways to express future actions