How to add multiple strings to one index in NSMutableArray
Having trouble adding objects to NSMutableArray in Objective C
Why can't Inuzuka clan's dogs use human language? Let $a_n=\cos(a_{n-1}), L=[a_1,a_2,...,a_n,...].$ Is there an $a_0$ such that $L$ is dense in$[-1,1]?$ How can I duplicate Apple's tiny USB power adapter? I'm designing a project that controls 110VAC (plug in, socket out), and also has a microprocessor inside.  I'd really like this project to not need a wall wart to get it's 5V, so I want to include a small DC power supply inside.    Apple's USB power adapter looks like a great small design that I can fit inside my case.  I'm guessing this is a switching power supply but I can't find any teardowns or schematics anywhere.  Does anyone know how this thing works?  I know I could make my own 110V->5VDC supply from a bridge rectifier and some caps, but I'd like to also be super safe.  What's in the Apple brick? In Ubuntu releases prior to Ubuntu 19.10 Eoan Ermine, when I run a command with sudo, that command receives my home directory in the $HOME environment variable. This is the behavior I have long expected and . If I want sudo to reset the $HOME environment variable, so that it refers to the target user's home directory instead of my own, I have to pass the -H option (or -i, though that does more).    ek@Kip:~$ lsb_release -d Description:    Ubuntu 18.04.3 LTS ek@Kip:~$ sudo printenv HOME  # Shows ek's home, not root's. /home/ek ek@Kip:~$ sudo -u as printenv HOME  # Shows ek's home, not as's. /home/ek ek@Kip:~$ sudo -H printenv HOME  # Shows root's home. /root ek@Kip:~$ sudo -Hu as printenv HOME  # Shows as's home. /home/as   When I first upgraded to Ubuntu 19.10, I was surprised to discover that sudo seems to reset $HOME no matter what! I continue to observe this now that 19.10 is released and I've installed updates--both on newly installed systems and one I upgraded to 19.10.  ek@Cord:~$ lsb_release -d Description:    Ubuntu 19.10 ek@Cord:~$ sudo printenv HOME  # Shows root's home, even without -H or -i. /root ek@Cord:~$ sudo -u as printenv HOME  # Shows as's home, even without -H or -i. /home/as ek@Cord:~$ sudo -H printenv HOME  # Also shows root's home. /root ek@Cord:~$ sudo -Hu as printenv HOME  # Also shows as's home. /home/as   I thought this might be due to .  But I checked, and always_set_home does not appear in any Defaults line in my 19.10 /etc/sudoers file.  What makes sudo treat $HOME differently starting in 19.10, and why was this change made? Does this make it safe to use plain sudo in cases where I would previously have used sudo -H? Generalized mean value theorem I know and understand the mean value theorem. But at the moment I don't have the intuition to understand the generalized mean value theorem     If $f$ and $g$ are continuous on the closed interval $[a,b]$ and differentiable on the open interval $(a,b)$, then there exists a point $c\in(a,b)$ where$$[f(b)-f(a)]g'(c)=[g(b)-g(a)]f'(c).$$If $g'$ is never zero on $(a,b)$, then the conclusion can be stated as$$\frac{f'(c)}{g'(c)}=\frac{f(b)-f(a)}{g(b)-g(a)}.$$   What is the intuition? And how can you prove this (generally) ? How to install Skype 4.3? Update values in one table based on contents of another Software Name: Oracle SQL Developer Version 17.2.0.188  I have three tables: orders, order_details, and products.  I wanted to run a query to update units_in_stock in the products table based on quantity in order_details, where the associated orders row has been marked as shipped, and has a shipping date.  Here's what I tried:  UPDATE Products SET (Products.Unit_In_Stock = Products.Unit_In_Stock - Order_Details.Quantity) INNER JOIN (     Orders INNER JOIN Order_Details ON Orders.Order_ID = Order_Details.Order_ID     ) ON Products.Product_ID = Order_Details.Product_ID WHERE (         ((Orders.Shipped_Date) IS NOT NULL)         AND ((Orders.This_Order_Was_Shipped) = "YES")         );   When I run this, I get:  Error at Command Line : 1 Column : 45   Line 1, Column 45 is the equal sign in the very first statement that said  Products.Unit_In_Stock = Products.Unit_In_Stock - Order_Details.Quantity   Can you help me get this working? What is the origin of the word  as in the interjection:     — It's hot in the desert.   — Well, duh!   If it is of onomatopoeic origin and only appears in modern English as some sites suggest, I would be interested to know when it started appearing in English writing. Remove HTML Tags from an NSString on the iPhone Does taking levels in a prestige class cause XP Penalty? Expected value notation in GAN loss I am reading Goodfellow's original  on GANs.  What I struggle to understand is his notation of the subscript in expected values.  $\mathbb{E}_{\boldsymbol{x} \sim p_{data}(\boldsymbol{x})}$ ....  If I understand it correctly then $\boldsymbol{x}$ is a realization of some random variable $\mathbf{x}$, but how can there be an expectation wrt. $\boldsymbol{x}$?  Or is $\boldsymbol{x}$ a random variable?  Thank you.  Edit: I do not think this is duplicate, as the referenced question does not answer what $\boldsymbol{x}$ means. Why not to extend the set of natural numbers to make it closed under division by zero? Yesterday, I was browsing the mobile Stack Overflow site. I noticed one thing: the textareas where you write your comments/answers are very buggy. I'm using a Samsung Galaxy S2, with the standard Android browser (Android version 4.1.2). There are a number of things that aren't working when typing your comment/answer.   Automatic spacing with Swype is disabled (however this might be because of Swype, not the site). Text navigation buttons (step left, step right, select text, copy text etc.) doesn't work with the on-screen keyboard, and selecting text by holding your finger over text is extremely difficult. When you paste something it always seems to be pasted at the top of your text, no matter where you try to paste it. Replying to another comment ("@Example User") does not show suggested people to reply to, like the full site does.   Is there anything I can do to solve these issues/bugs, or is it in the hands of Stack Overflow itself, and if so, should it be looked into?  Edit: I was using the mobile version of the site when noticing these bugs. I am always confused about where to put adverbs in sentences. For example, consider the questions below:        Why did they target us specifically?   Why did they target specifically us?   Why did they specifically target us?      I believe all these sentences mean the same. Am I correct? I am always confused about where to put adverbs such as always and specifically, etc. Is there a particular grammar rule for this?  Funny, you see, I can even form the above sentence in different ways.         I always confuse where to put this kind of adverb   Always I confuse where to put this kind of adverb Apply display settings to all user accounts? I was looking for some package (nautilus-terminal), and accidentally did this:  $ sudo apt-get install nautilus- Reading package lists... Done                                                                                                                                                                                                  Building dependency tree                                                                                                                                                                                                       Reading state information... Done                                                                                                                                                                                              The following packages were automatically installed and are no longer required:                                                                                                                                                  apturl apturl-common libgail-3-0 linux-headers-4.4.0-57 linux-headers-4.4.0-57-generic linux-image-4.4.0-57-generic linux-image-extra-4.4.0-57-generic                                                                       Use 'sudo apt autoremove' to remove them.                                                                                                                                                                                      The following packages will be REMOVED:                                                                                                                                                                                          gnome-session-flashback nautilus nautilus-sendto nautilus-share ubuntu-desktop                                                                                                                                               0 upgraded, 0 newly installed, 5 to remove and 69 not upgraded.                                                                                                                                                                After this operation, 2 031 kB disk space will be freed.                                                                                                                                                                       Do you want to continue? [Y/n] ^[[^C                                                                                                                                                                                             That's quite dangerous because remove is much harder to mistype than a simple dash from a failed autocompletion.     Is that an equivalent of apt-get remove? I couldn't find any documentation for that. Edit: except for overlooking the man page... How to trim whitespace from a Bash variable? I have a shell script with this code:  var=`hg st -R "$path"` if [ -n "$var" ]; then     echo $var fi   But the conditional code always executes, because hg st always prints at least one newline character.   Is there a simple way to strip whitespace from $var (like trim() in )?   or   Is there a standard way of dealing with this issue?   I could use  or , but I'd like to think there is a more elegant solution to this problem. Do the Ents go to the Undying Lands? $n$-th digit in the sequence of natural numbers What's the $n$-th digit in the sequence $S$ of numbers formed by the natural numbers, i.e.,  $n$-th digit in the sequence 1 2 3 4 5 6 7 8 9 10 11 12... ? For example 11th digit in the sequence is 0. How to understand Cauchy's proof of AM-GM inequality(the last step)