I'm using php5.6 and something is wrong with the code below      $a = (float)4.2;     $b = (float)1.4*3; // But 2.1*2 works       if ($b === $a) {         die("Equal 1");     }     else if ($b == $a) {         die("Equal 2");     }     else {         die("Not Equal");     }   The result always is "Not Equal"  Many thanks!!!
Consider the following code:   0.1 + 0.2 == 0.3  -&gt;  false   0.1 + 0.2         -&gt;  0.30000000000000004   Why do these inaccuracies happen?
What's the difference between "uname -r" and "uname -v"? What is the rule to convert the 'mm' notation to the 'optical zoom' notation? I searched a bit and found this one:  optical zoom = maximum focal length / minimum focal length   For example a 18-55mm lens would have a 3x optical zoom, and a 18-200mm lens would have a 11x optical zoom. Is that right? Creating point features with exact coordinates in QGIS Term or phrase describing action occuring when not watching I am an IT professional. More specifically in automation. I am looking for a term or phrase that describes the event when either:  a. you are watching something closely and the issue doesn't occur  or  b. you are not watching something at all and the issue does occur A couple years ago, it was easy to root any device: Install KingRoot, KingoRoot, or a similar app, hit the large ROOT button, and let it do the rest. After 5 minutes or so, a green "Root Succeeded!" prompt will pop up, and we can choose to keep the root app, or uninstall it and install a clean root manager app like SuperSU/Superuser.  How do they work? Why aren't they working anymore? And if they work, should I use them or not? Pixel Perfect 2D tiles I'm trying to make an 64x64 tilemap using Super Tilemap Editor &amp; Unity but my tiles looks terrible. I did my research about pixel perfect 2D and all of the solutions were for pixel art, they didn't work for me.  I have the following tileset I made in Adobe Illustrator as an example    Tiles looks like this when placed in game (1x zoom)    I'm pretty sure they're not 64x64 in game, they also look pixelated probably because they're smaller than they actually are on camera.  So my question is, how can I calculate the correct camera size for 64x64 tiles and do I have to make any changes in order to make sprites look pixel perfect? I'm currently using 1080/64/2=8.4375 (vertical resolution / PPU / 2) as camera size. Are there any research careers except professorship for a person holding PhD in pure mathematics? "For someone used to the tiny creatures we get in England it was something of a shock."  I think, in this sentence, relative pronouns before some words have been omitted. I know rules of omitting relative pronouns, but in this case I have failed to understand before which words relative pronouns can be placed to understand the sentence perfectly, which has been stated above. Please, explain the rules of omitting relative pronouns with the help of the sentence stated above, so that I can be able to understand this type of sentences easily. You can also use other sentences to explain this fact clearly.  Thanks to everyone. $X_1, X_2, \ldots, X_n$ are $n$ i.i.d. uniform random variables. Let $Y = \min(X_1, X_2,\ldots, X_n)$. Then, what's the expectation of $Y$(i.e., $E(Y)$)?  I have conducted some simulations by Matlab, and the results show that $E(Y)$ may equal to $\frac{1}{n+1}$. Can anyone give a rigorous proof or some hints? Thanks! In Star Trek, does the original die in teleportation? I am just curious.  If I am teleported is the original me dead and the teleporter just makes another copy of me there[at destination]? "1 in 10 are" or "1 in 10 is"? Take the examples:   "One in ten children are dyslexic."  "One in ten children is dyslexic." "One in ten children has dyslexia." "One in ten children have dyslexia."   The "one" is singular so 2 and 3 should be correct. But the "one in ten" is a fraction" so 1 and 4 should be correct. And yet I think I usually say 1 and 3. Which is/are correct?! pgfmathanglebetweenpoints always returns 90 I'm planning to buy a new Android phone and I'd like to be able to transfer the progress I have made at several games to the new device, so I won't have to play all the levels again from scratch.  I currently have an HTC Desire and will buy an HTC Evo 3D.  There's probably no simple/general solution to this.  But I was wondering if anyone did something similar and could provide some advice (e.g. where to look for files that might hold game progress information). Calculating the area of an irregular polygon Given the length of the sides of an irregular polygon (no coordinates provided) how do you compute the area of the maximum area of the polygon?   Thanks in advance We often see new users make offtopic, low quality posts, with broken English and cries for help. These questions look significantly different from most on SO.  When I worked in publishing, we would frequently receive documents that were incorrectly formatted. This was a major problem and we wasted a lot of time sending emails back and forth.  I made a small JavaScript quiz asking our authors about the formatting directions and the number of emails drastically dropped. I felt this was much nicer than simply rejecting them, additionally providing us a chance to make the directions more clear.  It is slightly unconventional but, would showing new users a quiz where they have to identify good and bad posts help to improve the quality of SO questions?  Edit (3/8/2017)  Recently a Norwegian website got some media attention for . When is it correct to use "yourself" and "myself" (versus "you" and "me")? When would you use the Builder Pattern? What are some common, real world examples of using the Builder Pattern?  What does it buy you?  Why not just use a Factory Pattern? I read that this is because the mean and variance completely specify a normal distribution. However, e.g. for a Poisson distribution the mean, variance and third moment can all be expressed with the same parameter lambda. Is this not what it means to 'completely specify' a distribution?  What is an example of two Poisson distributions having the same mean, variance and different higher moments? If we treated weak stationary as if it was strict stationarity, what would happen when we try to do time series analysis? I was reading the CernCourier, my favorite source of message on Higgs and friends. I was rather shocked, when I saw this:     "The mechanism by which neutrino mass is generated is not known."   What? Not known?  says: In Higgs-based theories, the property of 'mass' is a manifestation of potential energy transferred to particles when they interact ("couple") with the Higgs field, which had contained that mass in the form of energy.  Does this mean that neutrinos don't couple to the Higgs field? What is a Generic Handler in asp.net and its use?