gsub and str_extract
How do I match any character across multiple lines in a regular expression?
Motivation behind standard deviation? How to display a video in a web page using html,php How to format a USB drive? As far as I know, those are the only two.  They should be pronounced Soogher and Soor, shouldn't they?  I looked them up on Dictionary.com, and their etymologies reveal no trace of an SH, except where the listing for sugar had:     Middle English sugre, sucre (noun) &lt; Middle French sucre  &lt; Medieval Latin succārum  &lt; Italian zucchero  &lt; Arabic sukkar;  obscurely akin to Persian shakar, Greek sákcharon   I see an obscure kinship to shakar, but the word morphed so many times since then that the SH disappeared pretty much completely.  And sure is even worse, with no sign of SH:     Middle English sur ( e ) &lt; Middle French sur, Old French seur  &lt; Latin sēcūrus   Why are these the only two like this? Is there any substantial disadvantage to booking two one-way tickets, versus a round trip ticket?  Booking vacation travel with family of four for winter, from Northeast US to Mexico.  Round trip is pricy and no preferred travel times.  Two one ways is slightly cheaper with much preferred timing.      Different airlines there and back, both reputable national US carriers. "He didn't know where New Jersey was" I know the past tense carries the past tense in every dependent clause, but referring specifically to places or to things that are eternal, like the Earth, seems a bit weird and therefore we sometimes (I believe incorrectly) say     He didn't know that New Jersey was actually on the East Coast.   Because it still is. Or     He thought the Earth was round.   So is it square now?  Logically speaking, would you consider the use of past tense here a bit confusing in a day-to-day speech in these examples? Would you instinctively opt for using the present tense? Difference between static class and singleton pattern? How to change the shadow color in Blender Cycles? I want to change the color of the shadow casting by a cube to green. While it's very easy to do it in Blender Internal (you select the lamp, go to the Lamp data header and change the shadow's color in the Shadow panel) in Cycles there're no such options. How to achieve it in Cycles? How to check if element is visible after scrolling? I'm loading elements via AJAX. Some of them are only visible if you scroll down the page. Is there any way I can know if an element is now in the visible part of the page? The conditions $a^2b^2=b^2a^2$ and $a^3b^3=b^3a^3$ make the group $G$ abelian? Do I need a passport to visit Edinburgh in Scotland from elsewhere in the UK? I'm visiting Scotland for the first time this week, Edinburgh. I've lived in the UK for over 10 years but my nationality is Spanish. I only have a Spanish passport.  I'm also traveling by train.  Do I need a passport to enter Scotland and stay in my booked hotel? After Windows 10 Fall Creators Update, a svchost.exe instance is constantly using CPU time Since installing the Windows 10 Fall Creators Update, I have a svchost.exe process that is constantly using about 14​ % of CPU time:    This svchost.exe instance is responsible for hosting three services:    The CPU time is consumed by a thread inside that process that  cannot attribute to any of these three services:    Given that these three services are considered critical system services, it's hard to do anything about them. These services cannot be stopped or disabled by services.msc, and terminating the process triggers a bugcheck (CRITICAL_PROCESS_DIED). Disabling the Windows Defender Firewall through the settings UI does not reduce CPU usage.  I'm out of ideas. What could be causing this? How can I debug this further? Is there a workaround to stop these services?    Update: After some debugging with , we've isolated this to the Windows Defender Firewall service. Process Monitor shows that it's constantly accessing the registry:    A CSV export of a Process Monitor capture, filtered to that process, is available .  I’m still looking for a way to stop that behavior.    Update 2: Analysis with the Windows Performance Analyzer shows that most CPU time is consumed by code from rpcrt4.dll: Young Adult book about kids being bred for genetic purity in a world where races no longer exist I'm looking for a book I read in Junior High (probably) about a world where everyone was basically the same race.  One genetically pure male and female teenager of each race still exists.  They are transporting a genetically pure boy to meet his genetically pure female counterpart and accidentally introduce him to a genetically pure female of a different race.  And, of course, chaos ensues.  Any thoughts? I had a look at Knuth's The Art of Computer Programming, book 1. In chapter 1, section 1.2.2, exercise 25, he presents the following algorithm for calculating logarithm:  given $x\in[1,2)$, do the following:  L1: [Initialize] Set $y\leftarrow0$, $z\leftarrow x/2$, $k\leftarrow1$.  L2: [Test for end] If $x=1$, stop.  L3: [Compare] If $x-z&lt;1$, go to L5.  L4: [Reduce values] Set $x\leftarrow x-z$, $z\leftarrow x/2^k$, $y\leftarrow y+\log_b(2^k/(2^k-1))$, and go to L2.  L5: [Shift] Set $z\leftarrow z/2$, $k\leftarrow k+1$, and go to L2.  (The algorithm needs an auxiliary table which stores $\log_b2$, $\log_b(4/3)$, and so on, to as many values as the precision of the computer.  Then Knuth concludes: this exercise is to explain why the above algorithm will terminate and why it computes an approximation of $y=\log_b x$.  Well, I see that it works, but I am not able to explain why... Evaluate $\lim_{n\rightarrow\infty} \int_0^1 f(x^n) dx$ In Windows 7, How to query times, when the computer was locked? Is there a way to get a list of the following times:  whenever windows is locked (using windows+l combo)  whenever windows is unlocked in the past week?   I've tried poking in the event log, to no avail. Many thanks! Let $\alpha, \beta \in \mathbb{C}$, such that $\alpha + \beta$, and $\alpha\beta$ are algebraic. Show that $\alpha$ and $\beta$ are algebraic. Let $\alpha, \beta \in \mathbb{C}$,  such that $\alpha + \beta$, and $\alpha\beta$ are algebraic. Show that $\alpha$ and $\beta$ are algebraic.   attempt: Suppose $\alpha, \beta \in \mathbb{C}$ such that $\alpha + \beta$, and $\alpha\beta$ are algebraic.  Let $\alpha + \beta$, $\alpha\beta$ are algebraic be algebraic over $F$. And let $\alpha, \beta \in K$, where $K$ is an extension of $F$.  then $\alpha + \beta $ and $\alpha\beta$ lie in the extension $K = F(\alpha,\beta)$, which is finite over $F$.  so $[F(\alpha, \beta) : F] = [F(\alpha, \beta): F(\alpha + \beta, \alpha\beta)][F(\alpha + \beta, \alpha\beta) : F] \leq 2[F(\alpha + \beta, \alpha \beta) : F] $, since $\alpha + \beta$ and $\alpha \beta$ are roots .   So $[F(\alpha + \beta) : F]$ is finite and in the extension $F(\alpha,\beta)/F$ the elements must be algebraic over $F$, then $\alpha , \beta$ are algebraic.  Can someone please verify this? Or help me give a better approach. Thank you! Let $a,b,c>0$ such that $a+b+c=3$, find max/min of $\frac1{a^2+1}+\frac1{b^2+1}+\frac1{c^2+1}$ Why don't I have this option?    here's my disk layout  sudo fdisk -l  Disk /dev/sda: 640.1 GB, 640135028736 bytes 255 heads, 63 sectors/track, 77825 cylinders, total 1250263728 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x5b53cc54     Device Boot      Start         End      Blocks   Id  System /dev/sda1   *        2048      409599      203776    7  HPFS/NTFS/exFAT /dev/sda2          409600  1153767021   576678711    7  HPFS/NTFS/exFAT /dev/sda3      1216962560  1250050047    16543744    7  HPFS/NTFS/exFAT /dev/sda4      1250050048  1250261679      105816    c  W95 FAT32 (LBA)  Disk /dev/sdb: 4005 MB, 4005527552 bytes 32 heads, 63 sectors/track, 3880 cylinders, total 7823296 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x20d8782d     Device Boot      Start         End      Blocks   Id  System /dev/sdb1   *          63     7822079     3911008+   c  W95 FAT32 (LBA) QGIS: ESRI shapefile .shp no longer appears in list of file types under Add Vector Layer I recently installed QGIS 2.18.4 after using ArcMap for many years. I want to add several existing ESRI shapefiles (.shp) created in Arc, to a QGIS project. To add a new layer in QGIS, I select the "Add Vector Layer" button and then click "Browse" to go find the layer. Then I navigate to the proper folder. However, the drop down menu at the lower right of the "Open an OGR Supported Vector Layer" window does not include ESRI Shapefile on the list. The first one on the list is GeoJSON. Everything after "G" appears to be okay (all the way down to "X-Plane/Flightgear") but any file formats from A through F have been cut from the list. Since "ESRI" starts with "E" it does not show up on the list. Strange thing is when I first installed QGIS, ESRI Shapefile appeared on this list. So I must have accidently done something to change how that list is populated and I want to know how to change it back.   If I type in the name of the ESRI shapefile that I know is in the folder, it and all other files starting with those letters appears in the prompt window that appears. And QGIS will correctly load the Shapefile. However, I want to be able to see all those ESRI Shapefiles without having to know and type in the first letter so it will appear in the prompt. I want it to appear in the file type drop down (or drop up?) menu.