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How to fix "Notification access is not available" on Android Go?
What happens when my aasimar Celestial warlock has overlapping class and racial features? If you are an Aasimar warlock whose otherworldly patron is The Celestial, you will know the light cantrip from both race and class. Additionally, once you reach 6th level in warlock you will have resistance to radiant damage from both race and class.  Is there any ruling on what happens when you have overlapping class and race features? ${!FOO} performs a double substitution in bash, meaning it takes the (string) value of FOO and uses it as a variable name. zsh doesn’t support this feature.  Is there a way to make this work the same in bash and zsh?  Background:  I’ve got a list of environment variables, like  PATH MAIL EDITOR   and want to first print the variable names and afterwards their values.  This works in bash but not zsh:    for VAR in LIST do         echo $VAR         echo ${!VAR} done   It should be somehow possible “the old way” with eval, but I can’t get it to work:  for VAR in LIST do         echo $VAR         echo `eval \$$VAR` done   I’m never going to understand why I can’t simply do arbitrary deep substitutions like ${${VAR}} or even ${${${VAR}}} if need be, so an explanation for that would be nice, too. "This site is all about getting answers. It's not a discussion forum. There's no chit-chat." The warlock's Thirsting Blade eldritch invocation cannot be normally used with the (non-warlock) class feature Extra Attack, since both feature explicitly say you attack twice instead of once. But it seems to me that you could use both features (if you have them) when using Two-Weapon Fighting.  Assume your character is wielding two light weapons, one of which is your pact weapon. You take the Attack action on your turn to attack twice with your non-pact weapon using your  class feature.  Then, given the Two-Weapon Fighting rules, you use your bonus action to attack once using your pact weapon this time.  The  rules (PHB p. 195) state:     When you take the Attack action and attack with a light melee weapon that you're holding in one hand, you can use a bonus action to attack with a different light melee weapon that you're holding in the other hand.   But since your have the Thirsting Blade invocation, and you used the Attack action, you get to attack twice with your pact weapon.  The Thirsting Blade  (PHB p. 111) says:     You can attack with your pact weapon twice, instead of once, whenever you take the Attack action on your turn.   Does this combo work within the rules, or is there any interaction I'm not aware of? Electrical outlet on a dimmer switch? I live in an older house and have some outlets in our kitchen that don't make sense to me. We have one outlet that is tied to a dimmer switch on the opposite side of the room. I can detect that the outlet is hot using my voltage detector (when the dimmer switch is all the way on), but it pulses. I get about 6-7 beeps, then it skips one, beeps 6-7 more times, skips, continue. My GFCI tester shows an open hot. The outlet doesn't work.  I'm not very experienced with electrical work but this sounds highly unusual to me. Where should I start with fixing the issue? Could someone with experience in using these exercise typesetting packages please offer a quick compare and contrast of these packages to help me choose?  Packages under consideration are:         Having read briefly the documentation, they all seem to do the same thing generally, so could you please focus on the differences?  Some differences will not be obvious until I've learnt and used all the different packages but I want to better appreciate the differences now, a priori. What's wrong with this demonstration?:  $$A \iff 1 = 1^1$$ $$A \implies 1 = 1^\frac{2}{2}$$ $$A \implies 1 = (1^2)^\frac{1}{2}$$ $$A \implies 1 = ((-1)^2)^\frac{1}{2}$$ $$A \implies 1 = (-1)^\frac{2}{2}$$ $$A \implies 1 = (-1)^1 = -1$$  So finaly we get  $$1 = -1$$ How do I execute a file from a FAT USB drive? I'm trying to install a portable app onto my USB drive such that it is compatible with both Ubuntu and Windows (specifically, a program called eToys). Support is already built into the app for both operating systems - there's etoys.sh for Ubuntu and etoys.exe for Windows. I decided to install onto a FAT drive since that can be read from both systems. This works fine for Windows, but for some reason I cannot execute etoys.sh on Ubuntu.  The problem is not with the file - when the whole folder is copied to the local hard drive, the app works great in Ubuntu. But when I try to execute it from the USB, it opens the file in a text editor.  I then tried to run it from a terminal, but I got the message Permission denied.  I've had the same problem with other executables as well.  Is there an easy way to execute things from a USB stick? In the book Principles of Physics by Resnick Halliday: The decrease in Potential energy of a parallel plate capacitor due to a dielectric is because the slab would start to oscillate and the energy would transfer back and forth between the kinetic energy of the moving slab and potential energy stored in the electric field. First of, can somebody provide me the math of the SHM and could somebody explain why it would become the potential of the capacitor i.e. the electric field and not the potential of the slab? As the slab is doing SHM, shouldn't the slab(and not the capacitor) have potential energy at one point of time and kinetic at another like a spring? If the SHM is because of the electric field due to the conducting plates in capacitors, won't they always be in one direction (Plus, it's magnitude is not even a function of distance!)? Could someone be kind enough to provide the math and the reason for Potential and Kinetic Energy transfer question? How do I extract text that lies between parentheses (round brackets)? I have a string User name (sales) and I want to extract the text between the brackets, how would I do this?   I suspect sub-string but I can't work out how to read until the closing bracket, the length of text will vary. I performed principal component analysis (PCA) with R using two different functions (prcomp and princomp) and observed that the PCA scores differed in sign. How can it be?  Consider this:  set.seed(999) prcomp(data.frame(1:10,rnorm(10)))$x              PC1        PC2  [1,] -4.508620 -0.2567655  [2,] -3.373772 -1.1369417  [3,] -2.679669  1.0903445  [4,] -1.615837  0.7108631  [5,] -0.548879  0.3093389  [6,]  0.481756  0.1639112  [7,]  1.656178 -0.9952875  [8,]  2.560345 -0.2490548  [9,]  3.508442  0.1874520 [10,]  4.520055  0.1761397  set.seed(999) princomp(data.frame(1:10,rnorm(10)))$scores          Comp.1     Comp.2  [1,]  4.508620  0.2567655  [2,]  3.373772  1.1369417  [3,]  2.679669 -1.0903445  [4,]  1.615837 -0.7108631  [5,]  0.548879 -0.3093389  [6,] -0.481756 -0.1639112  [7,] -1.656178  0.9952875  [8,] -2.560345  0.2490548  [9,] -3.508442 -0.1874520 [10,] -4.520055 -0.1761397   Why do the signs (+/-) differ for the two analyses? If I was then using principal components PC1 and PC2 as predictors in a regression, i.e. lm(y ~ PC1 + PC2), this would completely change my understanding of the effect of the two variables on y depending on which method I used! How could I then say that PC1 has e.g. a positive effect on y and PC2 has e.g. a negative effect on y?    In addition: If the sign of PCA components is meaningless, is this true for factor analysis (FA) as well? Is it acceptable to flip (reverse) the sign of individual PCA/FA component scores (or of loadings, as a column of loading matrix)? My teacher told me that two parallel lines have a point of intersection, it is called Point at infinity. But I I can't understand how it can be true or how was it proved, can someone explain this to me?  Thank you. An elementary question regarding a multiplicative character over finite fields I have the formula $x! + y! = z!$ and I'm looking for positive integers that make it true. Upon  inspection it seems that x = y = 1 and z = 2 is the only solution. The problem is how to show it.   From the definition of the factorial function we know $x! = x(x-1)(x-2)...(2)(1)$  So we can do something like this:  $$ [x(x-1)(x-2)...(2)(1)] + [y(y-1)(y-2)...(2)(1)] = [z(z-1)(z-2)...(2)(1)]$$   we can then factor all of the common terms out on the LHS.  $$ [...(2)(1)][x(x-1)(x-2)... + y(y-1)(y-2)...] = [z(z-1)(z-2)...(2)(1)]$$ and divide the common terms out of the right hand side  $$[x(x-1)(x-2)...] + [y(y-1)(y-2)...] = [z(z-1)(z-2)...]$$  I'm stuck on how to proceed and how to make a clearer argument that there is only the one solution (if indeed there is only the one solution).   If anybody can provide a hint as to how to proceed I would appreciate it. An English book tells me that the following sentence is correct:     This publication is made from paper from sustainable forests.   Shouldn't it be of paper instead? I'm not sure if there's a better place to ask this or not.   Why, at least here in America, is the standard electrical system set up for alternating current (AC) rather than direct current (DC)? I'm just completing a long-distance move and realizing how many DC adapters I have and how many of my devices require DC power:   All of my guitar pedals. My alarm clock. My external hard disks. My USB car HDD dock.   ... and the list goes on. If we're almost constantly having to use DC adapters to convert AC into DC, why isn't the standard DC, other than because people resist change? How to draw good arrows explaining parts of equation? Creating Centrelines from Road Polygons/Casings using ArcGIS Desktop? I want to create center lines from road polygons.   Are there any automated tools in ArcGIS for Desktop to do this?  I am including a Screenshot of my vector file below. Allow moderators to fine-tune the effects of a lock Current Situation  When a moderator locks a question or answer, they can choose between different types of post notices: content dispute, off-topic comments, historical significance, wiki answer, or no notice. , but that it works this way is not clear to moderators and it is also not clear what effect a given notice has. The only way to find out for sure is to ask somebody who is not a moderator or use a sock. (This is due to moderator powers possibly overriding the effect of locks.)  Feature Request  Store the effects of a lock separately independent of the post notice. In the interface for locking a post, provide moderators with a checklist regarding the effects of the lock, for example:     This lock prevents:         answers   votes   flags   comments   edits      For questions, also add an option to apply the same lock to all answers to the question. For the canned lock reasons, automatically provide an appropriate choice as defaults.  At the very least make it clear in the dialogue what detailed effects a lock has.  Rationale  Post locks are used rarely, but when they are it is often for important reasons such as avoiding a divide of the community, an escalation of events, or similar. Thus, locks are a tool which moderators have little experience with, but whose correct use (i.e., choosing the right type of effects and knowing what the effects are) may be crucial. Moreover, many locks are used for special cases with individual needs, which in turn require individual locks.  In a specific example, there is a question on Academia, which lead answers and comments, whose appropriateness for the site is subject to a Meta discussion. To avoid further potentially inappropriate comments, answers, etc., I wished to lock question for the remainder of the Meta discussion. I chose content dispute as a lock reason, since it seemed most appropriate notice, however this only prevented edits to the question – which makes sense in other cases but not here. After I noticed this, I chose a historical lock (which I knew to be affecting everything) and removed the post notice (because it was not appropriate). The latter action lead to comments on answers being allowed (), which was not the desired effect either.  Related Questions    – This seems to be partially addressed: The different locks already do have different effects. However, my request goes further than this.  – This is about customising the notice not the effect.  – This would be addressed with this. I have recently been reading about Quantum Electrodynamics which I found very interesting, but even more confusing.  I understand photons mediate the electromagnetic force and interactions between charges can be described by virtual photon exchange. And that in Quantum Mechanics particles paths can be evaluated by sum over all paths...  An electron travelling from one point to another will take all paths, emitting and reabsorbing virtual photons. Does the electrons take all paths including those that involve faster than light velocities?  Is this question null, Does it mean anything to ask about properties of virtual particles?  Do I have the wrong idea about what virtual particles are?