public static String checkStatus(String status)     {         while((status != "s" || status != "S" || status != "m" || status !=    //this line is in the main program marital = checkStatus(marital);  //this is a method that keep asking for s or m if user input is not s or m public static String checkStatus(String status)  {   while(status != "s" || status != "S" || status != "m" || status != "M")   {    status = JOptionPane.showInputDialog(null, "Please enter M or S for marital status: ");    }   return status;  }     "M"))         {             status = JOptionPane.showInputDialog(null, "Please enter M or S for marital status: ");      }     return status; }   //I keep getting a infinite loop that ask for m or s
I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?
PHP global in functions df -h - Used space + Avail Free space is less than the Total size of /home As the output of df -h shows here, something is eating up 5GB of free space. So, it's not available to use.   I'm also noticing sometimes that the hard disk gets filled up to 100% sometimes. So, I had to restart the machine or delete some unncessary files. Only noticed these in /home partition. Don't know whether these two are related, but appreciate if anyone can put some insight into this.  $ df -h Filesystem            Size  Used Avail Use% Mounted on /dev/sda8             100G   92G  2.7G  98% /home How to make dried desert/cracked ground I am trying to create a cracked ground appearance for an animation that takes place in the desert. something like the image here:I would like to do this all in blender, and have blender generate the texture so I will not have to worry about unwanted ridges like those you would get in an image from the internet: I am wondering if there is a way to procedurally generate these cracks and use them with microdisplacements. Thank you! How to find $\lim\limits_{x\to0}\frac{e^x-1-x}{x^2}$ without using l'Hopital's rule nor any series expansion? Prove $(1+a+b)(1+b+c)(1+c+a)\ge 9(ab+bc+ca)$ How one can prove the following.  Let $a$, $b$ and $c$ be non-negative real numbers. Then the inequality holds:  $(1+a+b)(1+b+c)(1+c+a)\ge9(ab+bc+ca).$  WLOG one can assume that $0\le a\le b\le c$.  It is not difficult to prove the statement when $0\le a\le b\le c\le 1$ or $1\le a\le b\le c$. If H is a subgroup of G ( | G:H |=n, n > 1), then how can you show that G has a factor group G/N which is isomorphic to a subgroup D of the symmetric group Sn with |D| > 1.  I've been looking at Cayley's Theorem but it's not specific to the factor groups. What are the differences between executing shell scripts using "source file.sh", "./file.sh", "sh file.sh", ". ./file.sh"? How critical are macOS Mojave compatibility requirements? As per Apple support document, :     1. Check compatibility      You can upgrade to macOS Mojave from OS X Mountain Lion or later on   any of the following Mac models. Your Mac also needs at least 2GB of   memory and 12.5GB of available storage space, or up to 18.5GB of   storage space when upgrading from OS X Yosemite or earlier.         MacBook introduced in early 2015 or later   MacBook Air introduced in mid 2012 or later   MacBook Pro introduced in mid 2012 or later   Mac mini introduced in late 2012 or later   iMac introduced in late 2012 or later   iMac Pro (all models)   Mac Pro introduced in late 2013, plus mid-2010 or mid-2012 models with a recommended Metal-capable graphics card.      I am currently running macOS High Sierra on my Early 2011 MacBook Pro.  What does Apple's requirements mean for my ability to install Mojave? Is it possible or worthwhile to do so? Show that $\mathbb{Q}\times \mathbb{Q}$ is denumerable I am new to functions and relations, and with some concepts I am not so familiar. I have a question in an homework:     Show that $\mathbb{Q} \times\mathbb{Q}$ is denumerable.   From what I understood, denumerable means that it is infinitively countable. There are some  on the web about this topic, but I am still not understanding their explanation, maybe because they are not explained so easily (for me).  From what I understood, a set is denumerable if there's a relation with the natural numbers (but I am still not understanding what is this relation).  I have heard also about equinumerous sets (contain a bijective function = onto + one-to-one function), but I cannot relate this information with the problem to try to solve it. Show that for $\eta > 0$, $\alpha_\eta=-\infty$ and for the Cauchy problem $z'=x-z^2,z(0)=\eta$ the saturated solution is defined up to $+\infty$. We consider the differential equation $y'=x+y^2$ and for any $\eta \geq 0$ we denote by $\phi_\eta:(\alpha_\eta,\beta_\eta)\rightarrow\mathbb{R}$ the unique saturated solution of the Cauchy Problem $y'=x+y^2$, $y(0)=\eta$. I am required to do the change of variable $z(x)=y(-x)$ and I succeded here, obtaining $y'(-x)=y^2(-x)-x$ and so $z'(x)=x-z^2(x)$, then I was required to represent the $0-isocline$ and it was also simple as I obtained a parabolla and also I was required to write the equation of the tangent in the point $(0,\eta)$ which was also pretty simple as I obtained $\phi'_\eta(0)=\eta^2$ and the equation of the tangent is $y=\eta+\eta^{2}x$. Now, I am required to find $\phi^{(5)}_0(0)$( that $5$ indicates the number of differentiations), which puzzles me as I don't know the form of the solution and if it can be found out and also I am told to show that $\frac{1}{\eta}\geq\beta_\eta$ What I did not prove after the first edit : and that for $\eta &gt; 0$, $\alpha_\eta=-\infty$ and for the Cauchy problem $z'=x-z^2,z(0)=\eta$ the saturated solution is defined up to $+\infty$. At this last ones I am lost. Any help, please? Edit: I have passed beyond finding $\phi^{(5)}_0(0)$ and I think I did show that $\frac{1}{\eta}\geq\beta_\eta$, now it remains to prove the last questions. How to remove lines included in one file from another file? I have two lists, a complete list and a partial list. I want a bash script that will search the complete list for any lines that are in the partial, if there are, they will be removed from the complete list. Can anyone help? I was listening to the song  by Eminem. I've listened it before many times but from the time I've started learning English grammar I am getting confused while reading or listening English. This time I got stuck at the line "Too much pride, between you and I Not a jealous man but females lie". The phrase "between you and I" always sounded correct to me. But recently I learned that me is only used as an object and hearing that phrase sparked my head. Then I searched over the net and found on  that it is actually a hypercorrection.  says,      "...according to many grammarians and stylists a pronoun in a prepositional phrase in English is supposed to be in the oblique case...   ...though there is still disagreement on whether the phrase itself in today's language is grammatically correct or not."   My first question is, why is there a disagreement? Don't we always use the object form in the oblique case? If not then what are those cases?  Secondly, I want to know how common the phrase "between you an I" is? Is it used colloquially by common native English speakers. By common speakers I mean who don't bother grammar. I searched on  and got some results, e.g. . I found the phrase in another song -- . Is it a common mistake among native English speakers or is it used to give some special linguistic affect? I think this phrase has some linguistic affect that is why the singer would have given the name of her song "Between You and I". Because no one would like to use incorrect English in the title of a song, it must have some purpose. What attracted Padmé to Anakin? Negative R squared contradicts ssa/sst? I understand from this question -    that the R squared value of a linear regression model can be negative if the intercept is constrained. And this makes sense if you define R squared as -   $$R^2 = 1-\frac{SSE}{SST}$$  One says $SSE&gt;SST$. But then,  $$SST = SSA + SSE $$ Total Sum of squares  = Sum of squared errors + Sum of squared residual. And with this we get -  $$R^2 = \frac{SSA}{SST}$$ And now it is hard to imagine how $R^2$ can be negative. Aren't SSA and SST >0 always? How to increase swap space? I have, by default, 250MB of swap space in Ubuntu, and I want to expand it to a larger size. I need 800MB, which I think will be enough to open several applications without having to hit the current limit of swap. I hope someone can help me. Deleted downvotes should appear in Achievements dialog "Good morning.  Here is something awesome that you got last night!", said the Top Bar:    "21?  That must be two answer upvotes and, um, an answer that I downvoted that was deleted?", I thought.  Ok, let's look at the details and find out:    The +20 on my egrep answer is new and I've seen the other Achievements on the list, so where did the extra +1 come from?  In order to avoid confusion, the recent reputation changes in the dropdown should add up to the number in the notification.      I suspect this particular case is a bug.  Assuming the +1 is a downvote reversed by an answer deletion, I could see the argument for excluding it from the Achievements dropdown.  After all, it's not exactly something you accomplished.  Except it kinda is.  Part of the reason for downvoting is to  low-quality content.  The ultimate sign that such content was deemed beneath community standards is when it gets deleted.  I'm not sure that we should , but putting a note in your achievements in such cases seems like it would reinforce positive (albeit negative) behaviour.  This question is a feature request that rep gains from deleted downvotes be listed in the Achievements dialog, without getting into broader issues of displaying other activity on deleted posts such as those discussed in .  Thus, this is not intended to completely address the issue of the Achievements sum not adding up, but is intended to help encourage good community moderation by appropriate downvoting of low-quality content. Consider the following 2-variable function:     $$f(x,y) = \frac{x^2y}{x^4+y^2}$$   I would like to find the limit of this function as $(x,y) \rightarrow (0,0)$.   I used polar coordinates instead of solving explicitly in $\mathbb R^2 $, and it went as the following:  $$ x = r \cos \theta, \qquad y = r\sin\theta $$   Hence,  $$\lim_{(x,y) \to (0,0)} \frac{x^2y}{x^4 + y^2} = \lim_{r \to 0}\frac{r^2\cos^2\theta(r\sin\theta)}{r^4\cos^4\theta + r^2\sin^2\theta}$$  This simplifies to,  $$ \lim_{r \to 0} \frac{r^3 \cos^2\theta\sin\theta}{r^2(r^2\cos^4\theta + \sin^2\theta)}$$  Simplifying $r^3/r^2$, we finally get;  $$\lim_{r \to 0} \frac{r (\cos^2\theta\sin\theta)}{r^2\cos^4\theta + \sin^2\theta}$$  Now from the above, we find that as $r \to 0$ the limit is $0$.   I wanted to verify this answer so I checked on Wolfram Alpha. Explicitly without changing to polar coordinates, it said that the limit does not exist at $(0,0)$ and rightly so. Then how is it that with polar coordinates, the limit exists and is $0$? Am I doing something wrong in this method?  Also, what should I do in this situation, and when should I NOT use polar coordinates to find limits of multi-variable functions? Finding all differentiable $f(z) = u(x) + iv(y)$ in $\mathbb{C}$ where $u(x),v(y)$ are real valued functions.   I’m not sure what to do. Would $f$ be differentiable simply if and only if both $u$ and $v$ were differentiable?   My thinking is that if the limit $$ \lim_{h \to 0}\frac{f(z+h)-f(z)}{h} $$  exists then it would be equal to  $$ \lim_{h \to 0}\frac{u(x+h)-u(x)}{h} + i\lim_{h \to 0}\frac{v(y+h)-v(y)}{h} $$  and therefore would exist if they existed. But that doesn’t seem quite right.  I also thought about using Cauchy-Riemann equations, but seeing that I’m trying to find ones that are differentiable rather than those that aren’t, I thought they wouldn’t be of much help. How to get icons in Safari favorites (aka favicons) to display correctly? I am using Safari on macOS Sierra. I have added several commonly-used sites to my favorites section, like so:    (there are 10 icons, and all but 2 of them are displayed as the proper, correct icon from the site. For example, the Wikipedia icon has the large W icon. However, for Google Drive and Gmail, the icons are just big, ugly, generic G's)  I would like for the two Google sites to correctly display their icons as well. At first, I thought it was because all 8 of the "correctly displayed" sites had successfully configured their "Safari settings" or something like that, while Google failed to do this (although this doesn't sound too plausible).  However, if I instead go to the top menu in Safari, click Bookmarks > Show Bookmarks, I get the following:    Strangely, this time, the two Google sites do have correctly displayed icons, while it is instead three other sites (out of the 10) that aren't displayed: namely Wikipedia, Amazon, and New York Times.  So it seems that there are two sets of icons, "big" and "small", and for big icons, Google Drive and Gmail are not displayed correctly, while the other 8 are, and on the other hand, for small icons, Google Drive and Gmail are displayed correctly, while Wikipedia, Amazon, and NYTimes are not.  I actually don't care too much about the small icons, but I would really like for all the big icons to display correctly. How can I do that? Java: how to parse double from regex