I want to do something inside the if statement. But i cant able to do it since one error is coming in the code saying "cannot read property of undefined".  I don't understand. How can it not read cid[j][1] as its value is clearly equal to a number stored.   function checkCashRegister(price, cash, cid) {     let sum=0;     let change=cash-price;     let myarr=[];     for(let i=0;i&lt;cid.length;i++){       sum=sum+cid[i][1];     }     sum=Math.floor(sum*100)/100;      cid.reverse();     console.log(cid);      if(sum&gt;change){       let arr=[["PENNY", 0.01], ["NICKEL", 0.05], ["DIME", 0.1], ["QUARTER", 0.25], ["ONE", 1], ["FIVE", 5], ["TEN", 10], ["TWENTY", 20], ["ONE HUNDRED", 100]];        for(let j=0;j&lt;=cid.length-1;j++){         if(change&gt;=cid[j][1] &amp;&amp; change&lt;=cid[j+1][1]){          }       }       }     }      checkCashRegister(3.26, 100, [["PENNY", 1.01], ["NICKEL", 2.05], ["DIME", 3.1], ["QUARTER", 4.25], ["ONE", 90], ["FIVE", 55], ["TEN", 20], ["TWENTY", 60], ["ONE HUNDRED", 100]]);
Consider the following code:   0.1 + 0.2 == 0.3  -&gt;  false   0.1 + 0.2         -&gt;  0.30000000000000004   Why do these inaccuracies happen?
Portuguese tab names on profile page A few minutes ago, when I viewed profile pages on my phone, the tabs were all in Portuguese:   On the mobile interface:   On the full site     But it didn't happen on my desktop, and now it's back to normal.  Other users report that the site is normal, but  says it's still happening, so I've decided to post this bug report even though it seems to be working for me at the moment.   Perhaps it's some sort of intermittent problem.  I'm posting this on Meta.SE, since it seemed to happen on both Japanese.SE and ELL.SE, so it doesn't seem to be specific to a particular site. So, I got some laptop charger from my neighbor and I was thinking about to do something with it. Then one day I feel tiny shock from the output of the charger. I thought ac to dc filtering mechanism maybe shorted. Then I had tested other remaining charger to see if there was any AC current going on. And they all do the same. Is it normal to have flow some AC through DC ? Can I do something about it ? make it safer for work ? It does not feel like comfortable. Cannot move std::unique_ptr with NULL deleter to std::shared_ptr? How to add desktop shortcut for URL, ignoring web app manifest? Goal:  Have a desktop shortcut that opens  , ignoring the contained web app manifest that otherwise "overrides" the saved shortcut to  and with "display": "standalone".  I had this working previously on an older Android phone before a replacement / upgrade.  Prior to the upgrade, I was able to long-press and open individual articles in new tabs - as well as copy link shortcuts to specific articles, as well as all of the other features and functionality that Chrome has to offer.  Here is just a partial selection of references of other users complaining about the same:       Using  provides a temporary successful work-around.  However, I can't find a successful way to add a link for this to my home screen.  The "Add to Home screen" option within Chrome instead saves a link to  - and in such a way that it opens as a web application instead of a web page within Chrome:       On a desktop operating system, this would be a non-issue.  (Create shortcut, enter desired URL, done.)  Attempt 1: Provide my own Manifest  So I created my own manifest - editing  to change the start_url attribute to https://news.google.com/news/i#0, and the display attribute from standalone to browser.  I then created my own HTML page that simply contained the below - then self-hosted both on a local web server:  &lt;html&gt;         &lt;head&gt;                 &lt;Title&gt;Google News&lt;/Title&gt;                 &lt;link rel="manifest" href="/news/manifest.json"/&gt;         &lt;/head&gt;         &lt;body&gt;                 Test         &lt;/body&gt; &lt;/html&gt;   However, this doesn't work:  Despite the shortcut being saved with the desired name and icon, it links back to my self-hosted HTML page, and not the indicated start_url.  Unfortunately, it appears that cross-domain URLs are not allowed per the manifest intent - as per  and  .  Attempt 1b: MITM website  Within the confines of my own local network, I figured I could try to  (MITM) the website to temporarily provide a desired manfiest to use for addition to the home screen.  Unfortunately, the website uses  here, which appropriately blocks the attempt.  Regardless - this is way too much work for what should be a simple effort.  Attempt 2: Widget Bookmark  Unfortunately, it looks like the 1x1 bookmark widget was removed in Chrome 48, as per  .  The suggested work-around is to use the "Add to Home screen" feature within Chrome.  Goto 10 / see beginning.  Attempt 3: Use the default-provided "Internet" browser  Unfortunately, using "Add shortcut on Home screen" in the default-provided "Internet" browser produces the same result as Chrome.  Consideration 4: Use a custom app / widget  Could probably write and install a custom application or widget that could be added to the home screen to meet the goal.  Or don't re-invent the wheel, and use an existing one.  Some possibilities:   "More Shortcuts":  "Shortcut Customizer":    Conclusion  How can someone create a desktop shortcut to an arbitrary URL, ignoring a provided web app manifest? Increase close vote weight for gold tag badge holders In order to increase the efficiency with which poor quality questions are closed, it could make sense to have weighted close votes for a small subset of qualified users.   A very good way to measure the qualified users would be to leverage the tag badges. However, it needs to be rationally limited to a set of users that are knowledgeable with the subject. A very good way to measure the top users in a tag would be to look at those who have a gold badge in the tag.  If two users who have a gold tag badge pertinent to a question issue a close vote, the question should probably be closed (or probably will be very soon under the current system). I think it would make sense to allow users with a gold tag badge to have a 3x weight for close votes in those tags.  Please keep in mind, this isn't suggesting full moderator one click closure. It only adds weight to the vote. A single user could not do it on their own. These singular users cast close votes all the time, so that aspect would not change. Some will vote to close, some wont, but the ones who do should have a stronger weight to their vote. Even with 3x it will require 2 of said votes to accomplish, or still 2 other users (meaning 3 agreed it should be closed - which is the same amount of high rep users it takes to delete a question and that has a much greater impact than closure).  tldr;  Allow gold tag badge users to have a weighted close vote in their tag In the Harry Potter universe, there is a spell that unlocks things. In the books and movies, there are many occasions where the main characters use this spell to open doors in wizard buildings (such as the door leading to where the Philosopher's Stone is hidden, or a door in the Magical Congress Of USA headquarters). Hermione knows the spell in her first year, which seems to indicate it's pretty easy to learn/cast, especially for the average adult wizard.   What I'm wondering, then, is why do wizards lock their doors when it's so easy to unlock them? And if it's so easy to unlock locked doors, why aren't there more doors locked with enchantments? Is it possible to transfer Minecraft PE worlds to Minecraft PC? I'm learning how to use the mirror modifier and I am having some trouble.  When I apply the modifier to my object I don't see a mirrored version of it.  What am I doing wrong? On Linux can I keep a program running in background even after I disconnect? If I'm logged into a remote Linux machine, I know I can suspend a process (cntr-z) and move it to the background (bg 1) but if I disconnect from the machine, the process stops.  Is there a way I can leave it in the background and have it there when I log back in? This is a very long running process.  On Ubuntu, logged in via SSH. Need help in proving that $\frac{\sin\theta - \cos\theta + 1}{\sin\theta + \cos\theta - 1} = \frac 1{\sec\theta - \tan\theta}$ We need to prove that $$\dfrac{\sin\theta - \cos\theta + 1}{\sin\theta + \cos\theta - 1} = \frac 1{\sec\theta - \tan\theta}$$  I have tried and it gets confusing. Blender 2.8 : python code to switch shading mode (between wireframe and solid mode) If i switch between solid and wireframe mode, i can see in the info window that these commands are invoked :  bpy.data.screens["Layout"].shading.type = 'WIREFRAME' bpy.data.screens["Layout"].shading.type = 'SOLID'   Now i want to execute this command using python console. So i cut and paste the codes into python console but i got this error :   &gt;&gt;&gt; bpy.data.screens["Layout"].shading.type = 'WIREFRAME' Traceback (most recent call last):   File "&lt;blender_console&gt;", line 1, in &lt;module&gt; AttributeError: 'Screen' object has no attribute 'shading'  &gt;&gt;&gt; bpy.data.screens["Layout"].shading.type = 'SOLID' Traceback (most recent call last):   File "&lt;blender_console&gt;", line 1, in &lt;module&gt; AttributeError: 'Screen' object has no attribute 'shading'   Does anyone know why ? and what the correct script should i use in python console ?  Thanks The recent  about a new supermassive virus being discovered got me thinking about how we define viruses as non-living organisms whilst they are bigger than bacteria, and much more complex than we first gave them credit for.   What biological differences between viruses and cellular organisms have made viruses be deemed non-living? DEF file syntax error in visual studio 2012 Solve the second order ODE $(2x^2 + 1)y'' − 4xy' + 4y = 0$ I need help solving this past exam question, the professor posted exam questions with out solutions to last year's exam, I tried reduction of order, however that seemed to complicate things. And then I tried Euler-Cauchy method however I realized that won't work due to the $(2x^2 + 1)y''$.  Given $y_1=x$ is a solution $$(2x^2 + 1)y'' − 4xy' + 4y = 0$$ Find the second solution $y_2$ for equation. I would like to take a picture of a street during the day to depict how much traffic and cars there are on the street.  Is there anyway to do this with a long exposure photograph?  I have a Nikon D90 and I set the f stop down to 1/16 (the lowest of my lens) and set the time to 2 seconds. Doing this, the exposure is almost saturated when taken around 5pm with the sun setting behind a tree. Doing this, the cars passing by were very hard to make out against the stationary background, being visible as a blur in the color of the car.  Perhaps this is not possible and I should just do this at night where the cars lights are much brighter than the background.  Please suggest how else I might depict the traffic in a photograph?  Are daytime long exposure photographs even possible? Give me a blank Comment box when I am Improving a Suggested Edit The suggested edit screen includes both the suggested edit, and the reason for the edit:        When you click to improve the edit, that comment is left as-is and hidden at the bottom of the post above the save edit button:        At the moment, when I Improve a Suggested Edit, the Comment text for that Edit is retained (though editable). It's unlikely that the comment would still apply (e.g. Suggester added a tag and Approver corrected a typo), so I would rather have the field blank.  Also, it's better to have a blank Comment than an incorrect one... many people don't bother changing the original Comment.  So that box should be blank like this instead: I have an external sound card which mostly works fine, except that when its first plugged in, or when I turn on my laptop, the volume gets set to 100%. That is, the overall system volume, as shown in the sound indicator.  What I'm looking for is a terminal command that will set that volume to 50%, so that I can run it on login and not have to worry that the first audio I play is going to blare out at me if I forget to turn the volume down. What commands allow you to change that volume, i.e. the one in the sound indicator?  I've poked around in gsettings and dbus, but have been unable to find anything that would let me set the system volume like that. I do know about alsamixer, but that's not the solution I'm looking for, since that doesn't allow me to change the volume using the sound indicator or my laptop's multimedia keys. R code to solve for probability of normal distributions? I don't understand which R code I am supposed to be using to figure these problems out. I brief explanation of what the code is doing would be amazing. The problems below are two different applications I'm expected to understand and I don't get either. Thank you!  Problem 1. Let Z~N(0,1) For each of the following, find c such that the equation is true.   a) P(Z&lt;c) = 0.8413  b) P(0&lt;Z&lt;c) = 0.3051  c) P(-c&lt;Z&lt;c) = 0.8664   Problem 2. X~N(3,4) compute  a) P(X&gt;3)  b) P(1&lt;X&lt;8)  c) P(-1.5&lt;X&lt;1) Is it possible to reset all folder permissions? I was wondering if it was possible to reset all the folders' rights. I was having trouble when trying to install LAMP on my Ubuntu 11.04 installation, and I modified many permissions like /var /etc and I want to cancel everything I did and have permissions set to how they would be after a new install. Why do we need both using namespace and include directives in C++ programs?  For example,   #include &lt;iostream&gt;  using namespace std;  int main() {  cout &lt;&lt; "Hello world"; }   Why is it not enough to just have #include &lt;iostream&gt; or just have using namespace std and get rid of the other?  (I am thinking of an analogy with Java, where import java.net.* will import everything from java.net, you don't need to do anything else.)