Why do different file managers show different internal storage free space
How disk space is used on Android device?
I am using App Backup &amp; Restore for creating backup of my apps but with KitKat its using the internal SdCard as Storage.  When I explicitly set the external SdCard path it gives the error that it is unable to create folder,  I have also tried with creating folder under android/data/[packagename]/files/ but it is still not able to do the same.  Is there any solution so that apps can use external storage for writing files.  Note : I don't want to ROOT my Phone. What does: Error Broken count >0 mean? Can any linear transformation be represented by a matrix? Use $\cal L$ to denote a linear transformation on some vector space. We know any matrix $\bf{A}$ can be viewed as a linear transformation by defining $\cal L:= \cal L(\bf{v})= Av$ where $\bf{v}$ is a vector. I am curious is any linear transformation can be represented by a matrix? If so, why? If not, can anyone help provide a counterexample?  In particular, projection of vectors onto a vector $\bf{b}$ is a linear transformation defined by ${\cal L(\bf{v})}=({\mathbf{v}} \cdot \frac{{\mathbf{b}}}{{|{\mathbf{b}}|}})\frac{{\mathbf{b}}}{{|{\mathbf{b}}|}}$. Can this linear transformation be represented by a matrix?  Thank you! tcpdump : lost packets Tips and resources for beginning designers Thanks to the internet, graphic design and programming are becoming increasingly overlapping fields.   As a programmer, I constantly find myself needing basic knowledge of Graphic Design, but have trouble locating thorough yet concise graphic design learning resources, and instead usually find bits and pieces of knowledge applicable to the task at hand.  Can you guys offer some tips or recommend some good books, tutorials, blogs, and websites which provide a beginner level overview of web design that have been, in your experience, effective and high quality learning materials. I'm not looking for tips on how to use image editing tools, but assuming a basic grasp of those, which resources and advice will best help a new designer create professional looking designs? Capital letters in "Theorem", "Conjecture" etc This is my first post and as you can probably guess I am a mathematician so I have no clue about grammar. I am writing a mathematical document at the moment and I would appreciate some advice on my usage of capital letters. Can somebody please confirm if the following are correct?  1) "We know by T​heorem 4.6.1 that..."   2) "the following c​onjecture, due to..."  3) In order to prove the "Mckay-Stevens $k$-covering C​onjecture, once needs to show that..."  I'm particularly confused about 3).  Many thanks for any help Phantom device showing on Google Play We've just been learning about complex numbers in class, and I don't really see why they're called numbers.  Originally, a number used to be a means of counting (natural numbers).  Then we extend these numbers to instances of owing other people money for instance (integers).  After that, we consider fractions when we need to split things like 2 pizzas between three people.  We then (skipping the algebraic numbers for the purposes of practicality), we use the real numbers to describe any length; e.g. the length of a diagonal of a unit square.  But this is when our original definition of a number fails to make sense- when we consider complex numbers, which brings me to my main question: what is a rigorous definition of 'number'?  Wikipedia claims that "A number is a mathematical object used to count, label, and measure", but this definition fails to make sense after we extend $\mathbb{R}$.     Does anyone know of any definition of number that can be generalised to complex numbers as well (and even higher order number systems like the quaternions)? Where do the bipolar jets of black holes come from? How are they formed? And why are they so bright? Why are there unwanted white lines appearing in a PDF print proof? I designed a christmas card and I normally print it on vista print.  When I ask for a print proof the outlines show. They don’t show when I print it at home.  Why are there unwanted white lines appearing in this PDF print proof and how can I solve this problem? First, I'll state some background that lead me to the question.  I was thinking about quantization of space-time on and off for a long time but I never really looked into it any deeper (mainly because I am not yet quite fluent in string theory). But the recent discussion about  got me thinking about the topic again. Combined with the fact that it has been more or less decided that , I decided I should give it a go.    So, first some of my (certainly very naive) thoughts.  It's no problem to quantize gravitational waves on a curved background. They don't differ much from any other particles we know. But what if we want the background itself to change in response to movement of the matter and quantize these processes? Then I would imagine that space-time itself is built from tiny particles (call them space-timeons) that interact by means of exchanging gravitons. I drawed this conclusion from an analogy with how solid matter is built from atoms in a lattice and interact by means of exchanging phonons.  Now, I am aware that the above picture is completely naive but I think it must in some sense also be correct. That is, if there exists any reasonable notion of quantum gravity, it has to look something like that (at least on the level of QFT).  So, having come this far I decided I should not stop. So let's move one step further and assume string theory is correct description of the nature. Then all the particles above are actually strings. So I decided that space-time must probably arise as condensation of huge number of strings. Now does this make any sense at all? To make it more precise (and also to ask something in case it doesn't make a sense), I have two questions:        In what way does the classical space-time arise as a limit in the string theory? Try to give a clear, conceptual description of this process. I don't mind some equations, but I want mainly ideas.   Is there a good introduction into this subject? If so, what is it? If not, where else can I learn about this stuff?      Regarding 2., I would prefer something not too advanced. But to give you an idea of what kind of literature might be appropriate for my level: I already now something about classical strings, how to quantize them (in different quantization schemes) and some bits about the role of CFT on the worldsheets. Also I have a qualitative overview of different types of string theories and also a little quantitative knowledge about moduli spaces of Calabi-Yau manifolds and their properties. How can I view the Android internal partition table? I've rooted my device, put it in recovery mode, and have linked it to PC by .  How can I view the list of storage devices and partitions?  Note: fdisk doesn't work. How to get back a declined Outlook invitation I accidentally clicked "decline" on an Outlook invitation and now I can't reverse it -- the event has completely disappeared from my calendar!  How can I get back the event invitation and change my "Decline" to "Accept" or "tentative"? Etymology of "dong" and "dongle" Dong as in ding-dong is clearly onomatopoetic as confirmed by :     ding dong        imitative of the sound of a bell, c.1560.   and similarly for :     ding (v.)       1819, "to sound as metal when struck," possibly abstracted from ding-dong, of imitative origin. The meaning "to deal heavy blows" is c.1300, probably from Old Norse dengja "to hammer," perhaps also imitative. Meaning "dent" is 1960s. Related: Dinged; dinging.   What, then, is the origin of dong to mean penis? Etymonline.com is  here:     dong (n.)        "penis," 1891, of unknown origin.   We also have a much more recent word, dongle, which has no entry at etymonline.com but  claims it is:     Apparently from dangle.   This leads me to the theory that the anatomical and onomatopoetic dongs  are not related and that the former usage, like dongle, derives from dangle. So, my questions are:   Is that so? Does dong (penis) derive from dangle? Sounds reasonable enough but I have found no definitive sources for it. Does dongle derive from dangle? It makes perfect descriptive sense for dong but the USB devices called dongles do not dangle but instead protrude quite rigidly, so I feel that dongle being derived from the cruder meaning of dong makes more sense. Can we add a section in our vf page and add components to it Can we add a section in our vf page and add components to it. I mean split my vf page into two parts and then add components to it. difference between "function foo() {}" and "foo() {}" I can define bash functions using or omitting the function keyword. Is there any difference?  #!/bin/bash  function foo() {   echo "foo" }  bar() {   echo "bar" }  foo  bar   Both calls to functions foo and bar succeed and I can't see any difference. So I am wondering if it is just to improve readability, or there is something that I am missing...  BTW in other shells like dash (/bin/sh is symlinked to dash in debian/ubuntu) it fails when using the function keyword. I would like to achieve this effect using my Nikon P510:      Are there any suggestions or tips that would help me do that? Computing dominant area in polygon using ArcGIS Desktop? Is password confirmation necessary on a Change Password dialog? On one hand there is no need to ask for password confirmation because it is annoying. If I made a mistake when confirming my password I'll need retype my very complex password again. There is also a button that can show/hide the password so I don't need retype it in order to confirm it.   However, some users don't use the password show/hide button and the 'forgotten password' option will be pain for them.  Twitter removed the password confirmation from registration but left the dual confirmation in place for changing password. Is this right approach? How do I install fonts? Question says it all. I need them to be available in gimp.