Null Pointer Exception on Shared Preferences on a Spinner control
What is a NullPointerException, and how do I fix it?
How can I play mp3 files or videos? Is the CMB rest frame special? Where does it come from? It seems that we are . This is the speed of our galaxy relative to the cosmic microwave background. Where does this rest frame come from? Is this special in any way (i.e., an absolute frame)? EDIT: I think the more important question is &quot;where does the CMB rest frame come from?&quot;. Why is my multimeter stopping device from booting when measuring current? I am using a BK Precision 2709B multimeter and attempting to measure the current of a device that runs off of a ~3.7V battery. The device boots up, initializes and then goes into its lower power state. If I use the 10A setting, my device boots up just fine but I need to measure uA or mA. When I attempt to use the mA setting, the device attempts to boot and then continuously reboots. Its not able to finish its initialization process before it cuts off. The current reading on the meter is ~30mA before the device cuts off and attempts to boot up again. The meter says 400mA max, so it doesn't seem like it is over the maximum allowed current for the mA setting. Is there anything I can do to get past the initialization so I can measure the lower power state? Is there a way to exclude other particle systems from the effects of a Wind effect? I have a scene with a number of particle systems. I'd like to have a separate wind effect for my main scene and another for an extra: an emitter + wind-effect to blow leaves into my scene. I can't find any way to exclude, so here I am. At the very worst, I can just render the main scene and then render the wind effect and composite it, but I figured I'd check first. How to add Windows to GRUB I have my encrypted Archlinux installed on my SSD. Now I have one HDD with Windows installed. But in my GRUB just Archlinux is shown (no Wonder, because I just installed Windows on the other HDD, GRUB doesn't know of that by now.).  My Question is, how do I properly add my Windows-HDD to GRUB, so that I can choose which to boot when starting?  I am a little bit afraid of destroying my GRUB so I can't boot my encrypted Archlinux anymore.  Thanks! What is ISCAS85 benchmark? What is ISCAS85 benchmark? I find it in a , is there any simulator for it? This question is about the net speed.  I'm from China, and I find that opening pages on Stack Overflow is very fast, normally within a range of 1 to 4 seconds. This speed is very good for a website outside China; it's even faster than some native websites.  Not every website outside China has such good speed, so I am wondering why and how Stack Overflow manages to be so quick. How to pull email address and password from text file with CMD? I have a text file named file.txt Which contains,  Combo: testing123mail@gmail.com:password As Combo:  abcdefghijklmnopqrstuvwxyz@gmail.com:ajfbdf some text here some more text here As Combo: hadvsfhia@ahfjbadj.com:password@1 some random text here iloveu@gmail.com:passypassyword123 goldenmammy@hotmail.com:youtube123   I am running the below code, to filter only mail:pass from the above text file file.txt  for /f "tokens=3" %%a in ('type file.txt^|find "As Combo:"') do &gt;&gt;mail.txt echo %%a for /f "tokens=2" %%b in ('type file.txt^|find "Combo:"') do &gt;&gt;mail.txt echo %%b for /f "tokens=1" %%c in ('type file.txt^|find ":"') do &gt;&gt;mail.txt echo %%c   Expected Output in mail.txt,  abcdefghijklmnopqrstuvwxyz@gmail.com:ajfbdf hadvsfhia@ahfjbadj.com:password@1 testing123mail@gmail.com:password iloveu@gmail.com:passypassyword123 goldenmammy@hotmail.com:youtube123   But, am getting actual output is,  abcdefghijklmnopqrstuvwxyz@gmail.com:ajfbdf hadvsfhia@ahfjbadj.com:password@1 testing123mail@gmail.com:password Combo: Combo: Combo: As As iloveu@gmail.com:passypassyword123 goldenmammy@hotmail.com:youtube123   Note: The mail id and passwords will be differ in different text file. Above given mail id and passwords are typed by me randomly for example.  Kindly fix my code and help to get expected output. Thanks in advance. Where can I travel for prolonged periods of time while legally working remotely for a company in my home country? I found several questions about inbound travelers to the US in this scenario, but little about other countries: I work for a company in my home country (USA) who are open to me working remotely while traveling.   Which countries allow me to legally work remotely for a company in my home country (USA) while traveling in their country? The work has absolutely no connection to the destination country, it would take place identically entirely within the USA if I weren't traveling. I was surprised to only recently notice that      An object of any density can be large enough to fall within its own   Schwarzschild radius.   Of course! It turns out that supermassive black holes at galactic centers can have an average density of less than water's.  Somehow I always operated under the assumption that black holes of any size had to be superdense objects by everyday standards.  Compare the Earth to collapsing into a mere 9mm marble retaining the same mass, in order for the escape velocity at the surface to finally reach that of light.  Or Mt. Everest packed into one nanometer.  Reading on about this , it increases proportionally with total mass.  Assuming matter is accumulated at a steady density into a spherical volume, the volume's radius will only "grow" at a cube root of the total volume and be quickly outpaced by its own gravitational radius.  Question: For an object the , what would have to be its diameter for it to qualify as a black hole (from an external point of view)?  Would this not imply by definition that:   The Earth, Solar system and Milky Way are conceivably inside this black hole? Black holes can be nested/be contained within larger ones? Whether something is a black hole or not is actually a matter of perspective/where the observer is, inside or outside? The help pages in R assume I know what those numbers mean, but I don't. I'm trying to really intuitively understand every number here. I will just post the output and comment on what I found out. There might (will) be mistakes, as I'll just write what I assume. Mainly I'd like to know what the t-value in the coefficients mean, and why they print the residual standard error.   Call: lm(formula = iris$Sepal.Width ~ iris$Petal.Width)  Residuals:      Min       1Q   Median       3Q      Max  -1.09907 -0.23626 -0.01064  0.23345  1.17532    This is a 5-point-summary of the residuals (their mean is always 0, right?). The numbers can be used (I'm guessing here) to quickly see if there are any big outliers. Also you can already see it here if the residuals are far from normally distributed (they should be normally distributed).  Coefficients:                  Estimate Std. Error t value Pr(&gt;|t|)     (Intercept)       3.30843    0.06210  53.278  &lt; 2e-16 *** iris$Petal.Width -0.20936    0.04374  -4.786 4.07e-06 *** --- Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1    Estimates $\hat{\beta_i}$, computed by least squares regression. Also, the standard error is $\sigma_{\beta_i}$. I'd like to know how this is calculated.  I have no idea where the t-value and the corresponding p-value come from. I know $\hat{\beta}$ should be normal distributed, but how is the t-value calculated?  Residual standard error: 0.407 on 148 degrees of freedom   $\sqrt{ \frac{1}{n-p} \epsilon^T\epsilon }$, I guess. But why do we calculate that, and what does it tell us?  Multiple R-squared: 0.134,  Adjusted R-squared: 0.1282    $ R^2 = \frac{s_\hat{y}^2}{s_y^2} $, which is $ \frac{\sum_{i=1}^n (\hat{y_i}-\bar{y})^2}{\sum_{i=1}^n (y_i-\bar{y})^2} $. The ratio is close to 1 if the points lie on a straight line, and 0 if they are random.  What is the adjusted R-squared?  F-statistic: 22.91 on 1 and 148 DF,  p-value: 4.073e-06    F and p for the whole model, not only for single $\beta_i$s as previous. The F value is $ \frac{s^2_{\hat{y}}}{\sum\epsilon_i} $. The bigger it grows, the more unlikely it is that the $\beta$'s do not have any effect at all. /A problem from the 2012 MIT Integration Bee is $$ \int_0^1\frac{x^7-1}{\log(x)}\mathrm dx $$ The answer is $\log(8)$. Wolfram Alpha gives an indefinite form in terms of the logarithmic integral function, but times out doing the computation. Is there a way to do it by hand? Doing a search via regular Gmail frontend in the browser, shows strange results.  I want to search all mails from   *@ebay.*   My search:  from:@ebay   shows also emails sent from an ebay subdomain:   eBay@reply.ebay.com   It seems like Gmail ignores the "@", otherwise I can't see why those messages appear in the search results.  I also tried following searches with no success:  from:"@ebay" from:'@ebay' from:(@ebay) from:("@ebay") from:('@ebay') I see this a lot, someone in a category of people attempts to shut down anyone with an opinion that is not from the same category. For example, people without children weighing in on parenting; the parent may say something like "well, since you don't have kids and I do, my position is of more validity than yours."  Another example: a drug user (of some kind) telling someone who has never done drugs and does not care to, "until you tried it, you have no right to judge me."  People frequently try to limit the consideration on opinions to those in their same group, while it is perfectly reasonable that the non-drug user, especially if they are a chemist or well read on the subject, may have an equally valid opinion, or even more valid. In fact some might even say that someone NOT in the category has a better chance of being objective and seeing the forest for the trees.  So what is the fallacy of trying to shut down opinions when the source of the opinion is not someone who has personally had the experience under discussion? Use central limit to solve a problem I am asked to solve the following question using central limit theorem. In an election between two candidates, A and B, one million individuals cast theirvote. Among these, 2000 know candidate A from her election campaign and vote unanimously for her.The remaining 998000 voters are undecided and make their decision independently of each other byflipping a fair coin.Approximate the probability pA that candidate A wins up to 3 significant figures.  It's easy to solve directly. PA = $\frac{0.5(10000-2000)+2000}{10000}$ = 0.501. However, I am quite confused about how to solve this problem by central limit theorem. Merging arrays with the same keys Can I choose not to defend against an attack? Playing D&amp;D4e, I have a situation in mind where a character could reasonably WANT to get hit with a normally harmful attack. Is there anything in the rules allowing the character to purposefully take the hit, not even bothering to attempt to defend or dodge out of the way of it?  For example, a dragonborn character makes a breath attack that includes an ally in its blast. The dragonborn has the Nusemnee's Atonement feat, which allows a player whose AOE damages an ally to take the ally's damage instead. This can be paired with a dragonborn feat that recharges your racial dragonbreath power when you take damage of the type it deals. This combination lets the dragonborn recharge their dragonbreath as long as they hit an ally with it. Normally you'd want your ally to at least have a chance to dodge your AOE first, but in this combo, it's best if they can allow themselves to get hit!  Can the ally choose not to defend against the attack, purposefully taking the hit, knowing that the character making the attack will take the damage in his place? Bluetooth disappeared in Windows 10 I have a Lenovo G580 laptop. In the past, using Windows 8, I could use Bluetooth to connect to other devices.  Installing Windows&nbsp;10, Bluetooth simply disappeared. I can't find anything related to Bluetooth in the Device Manager, also in Settings → Devices.  There is no Windows&nbsp;10 Bluetooth driver for my laptop.  What can I do? JDBC-ODBC Bridge queries to Access fail when they have accented characters Are data members allocated in the same memory space as their objects in C++?