What's the best way to compare character of an array to a string.      import java.io.Console;     class msd{     public static void main(String[] args){     Console console= System.console();     String letter="Hello";     String[] Arrayname=letter.split("");      if(Arrayname[0] == "H")     console.printf("success");     else     console.printf("failure");     }    }   Output      failure   Expecting to be success.

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?


When I run ipython notebook or gedit in Terminal, the command line does not appear and it stops somewhere. How can I go back to command line mode?

I use dwm as a window manager on Ubuntu, I like tiled windows and I like them as few as possible. I sometimes need to run an application (let's say it's the pdf viewer mupdf in x11) from the terminal, the application will be launched in a new window but the terminal from which I launched becomes this prompt-less console for that application to log whatever.  I use dmenu to launch applications, but sometimes an application needs arguments (file names) to start. I use uxrvt within x11 managed by dwm.


I am playing in a campaign where I am a water domain cleric water genasi. This means I am amphibious, and so I thought that I could cast spells underwater. When I tried to do this, the DM said you can't cast spells underwater, even when I told him I am amphibious.   Is it possible to cast spells underwater if I am amphibious?

My party recently tipped over a boat of enemies into what was essentially rapids and trapped the enemies in a cube of force underwater. The warriors inevitably drowned as they had no way out. However, trapped in the cube of force was a wizard with access to a teleportation spell (Misty Step) with a verbal component. Could the wizard use his spell with a verbal component underwater and escape a watery death? If the rules don't specify anything about verbal components underwater specifically, have any of the designers mentioned anything about this?  Note: as a 5e DM I made a ruling on the spot (decided to allow it on the condition that the caster goes directly from "holding breath" to "suffocating") so I am aware that it's within my power to decide how it works in my world. I'd just like to know if the rules or someone wiser than me has addressed this yet.


First, suppose $G_1, G_2$ are two finite groups and $|G_1|=|G_2|$.   If for each $n\in\mathbb N_+$,  we have $\#\{g_1\in G_1,o(g_1)=n\}=\#\{g_2\in G_1,o(g_2)=n\}$.  My question:  $1$. Can we always have $G_1\cong G_2$?  $2$. What if $G_1$ and $G_2$ are infinite groups?  $3$. What can be used to characterize a group?  For example, multiplication table, generator and relation, its all subgroups(especially Sylow p-sungroups), etc while character table can't.    Thanks for your time and effort.

Suppose we are given a finite group $G$, and suppose we know the order of $G$ as well as the orders of each of its elements.  Does this information alone uniquely determine the group up to isomorphism?  What if we add extra hypotheses about $G$ (solvable, simple, etc)?  If not, can we at least extract some useful information regarding its structure?    For example, if $|G| = 8$ and $G$ contains three elements of order $2$ and four elements of order $4$, then I know $G \cong \mathbb{Z}_4\times\mathbb{Z}_2$.


animals = ["dog","cat","lion","elephant"]  animals[-1:-3]  What is wrong with this? Gives me blank result

I need a good explanation (references are a plus) on Python's slice notation.   To me, this notation needs a bit of picking up.   It looks extremely powerful, but I haven't quite got my head around it.


I need to match the following pattern:  text1.cps.text2 text1.text2.cps.text3 cps.text1   where text1, text2 are some random words. cps is one of several possible words. So I wrote the following regexp:  pattern = "(\w+\.)*?({0})(\w+\.)*"   And than I iterate over list of possible words:  for word in ['cps.','cps.tbl.']:    p = pattern.format(word)   So the problem is that item from the possible words can contain special regex chars. So I am looking for function that replaces each special character into something like that:  cps\. and cps\.tbl\.

I want to use input from a user as a regex pattern for a search over some text.  It works, but how I can handle cases where user puts characters that have meaning in regex? For example, the user wants to search for Word (s): regex engine will take the (s) as a group.  I want it to treat it like a string "(s)" .  I can run replace on user input and replace the ( with \( and the ) with \) but the problem is I will need to do replace for every possible regex symbol. Do you know some better way ?


I have a couple of 18.04 VM's that all have the same problem: they do not seem to be using the correct DNS servers. These machines get their settings from DHCP, which looks like below:  $ netplan ip leases ens18  # This is private data. Do not parse. ADDRESS=192.168.100.60 NETMASK=255.255.255.0 ROUTER=192.168.100.1 SERVER_ADDRESS=192.168.100.1 T1=3600 T2=6300 LIFETIME=7200 DNS=192.168.6.1 8.8.8.8 DOMAINNAME=my.domain HOSTNAME=influx CLIENTID=<redacted>   I have randomized the numbers above, but the point is that the DNS servers listed are the correct ones coming from DHCP. However, if I attempt name resolutions with nslookup I get the following:  $ nslookup > test.my.domain Server:     127.0.0.53 Address:    127.0.0.53#53  ** server can't find test.my.domain: NXDOMAIN   However, I can explicitly use the DNS server as such:  $ nslookup test.my.domain 192.168.6.1 Server:     192.168.6.1 Address:    192.168.6.1#53  Name:   test.my.domain Address: 192.168.100.150   Can anyone explain why it defaults to 127.0.0.53 and why name resolution isn't working?  It's worth noting I have 16.04 VM's running along side these in the same subnet and they do not have the same issue (they resolve and nslookup works as expected).

My DNS server is 192.168.1.152.  This DNS is provided to clients by DHCP. The windows clients on my LAN resolve names properly using that DNS, but my Ubuntu VM doesn't.  The VM is set up with bridge networking and is being properly provided the DNS server, but my local hostnames aren't being resolved by nslookup or browsers.  Here is an nslookup of one of my local domains:  # nslookup unraid.local Server:     127.0.0.53 Address:    127.0.0.53#53  ** server can't find unraid.local: SERVFAIL   Here is what it should resolve by using my DNS server:  # nslookup unraid.local 192.168.1.152 Server:     192.168.1.152 Address:    192.168.1.152#53  Name:   unraid.local Address: 192.168.1.152   /etc/resolv.conf has a wrong nameserver:  # Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8) #     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN # 127.0.0.53 is the systemd-resolved stub resolver. # run "systemd-resolve --status" to see details about the actual nameservers.  nameserver 127.0.0.53   I ran that command. Under DNS Servers, confusingly, it specifies the correct server (and my default gateway).  root@ubuntu:~# systemd-resolve --status Global           DNSSEC NTA: 10.in-addr.arpa                       16.172.in-addr.arpa                       168.192.in-addr.arpa                       17.172.in-addr.arpa                       18.172.in-addr.arpa                       19.172.in-addr.arpa                       20.172.in-addr.arpa                       21.172.in-addr.arpa                       22.172.in-addr.arpa                       23.172.in-addr.arpa                       24.172.in-addr.arpa                       25.172.in-addr.arpa                       26.172.in-addr.arpa                       27.172.in-addr.arpa                       28.172.in-addr.arpa                       29.172.in-addr.arpa                       30.172.in-addr.arpa                       31.172.in-addr.arpa                       corp                       d.f.ip6.arpa                       home                       internal                       intranet                       lan                       local                       private                       test  Link 2 (ens33)       Current Scopes: DNS LLMNR/IPv4 LLMNR/IPv6        LLMNR setting: yes MulticastDNS setting: no       DNSSEC setting: no     DNSSEC supported: no          DNS Servers: 192.168.1.152                       192.168.1.1   I don't want to "hard code" the DNS server's IP in a config file because I won't be able to resolve when I change networks.  How can I get resolvconf and NetworkManager to automatically set the DHCP server's IP in /etc/resolv.conf?


I use ubuntu 14.04 I try to run logrotate each 10min and remove all logs files bigger then 2MB, I try a lot solution but nothing not work, my logrotate run just 1 per day, I try solution with moved logrotate from cron.daily to cron.hourly but not work, I try other solution and do next:  create file logrotate:  */10  *  *  *  *   root /usr/sbin/logrotate /etc/logrotate.conf   and add in:  /etc/cron.d   this is my /etc/logrotate.d/apache2:  /var/log/apache2/*.log /var/log/apache2/domains/*log {     weekly     missingok     rotate 10     maxsize 2M     compress     delaycompress     notifempty     create 640 root adm     sharedscripts     postrotate             /etc/init.d/apache2 reload > /dev/null || true             [ ! -f /var/run/nginx.pid ] || kill -USR1 `cat /var/run/nginx.pid`     endscript     prerotate             if [ -d /etc/logrotate.d/httpd-prerotate ]; then \                     run-parts /etc/logrotate.d/httpd-prerotate; \             fi; \     endscript }

This is a  about using cron & crontab.   You have been directed here because the community is fairly sure that the answer to your question can be found below. If your question is not answered below then the answers will help you gather information that will help the community help you. This information should be edited into your original question.  The answer for 'Why is my crontab not working, and how can I troubleshoot it?' can be seen below.  This addresses the cron system with the crontab highlighted.


I am considering to live in Kyiv for a couple of months. I visited the city last summer and it pleasantly surprised me. I would like to learn the local language to make my way around easier. Any suggestions?

I am traveling from the US, and the only language I really know is American English. I will be visiting cities in various districts of Ukraine: Kiev, Chornobyl, Cherkassy, Kherson, etc. I will be traveling with a native Ukrainian who is fluent in English.  I probably have 5-10 hours a week for the next few weeks before I leave to learn some basics of the languages. Should I focus only on Ukrainian, Russian, or some of each?  I understand Ukrainian is the official language and the most common native language of the population, and that Russian is the second most common language. I realize I won't learn much in just a few weeks, but I figure any bit I learn will help me understand more than I otherwise would.  Edit: @Karlson: Maybe I am kidding myself to think I will be able to learn enough even to be better than nothing. Am I just wasting my time? I wouldn't mind learning some greetings and maybe some basics of the writing and distinguishing one language from the other.


I want to generate $c$ correlated standard normals where the correlation matrix M is something like \begin{matrix}         1 & \rho & \rho \\         \rho & 1 & \rho \\         \rho & \rho & 1 \\ ....         \end{matrix}  so ones along the diagonal but otherwise all variables have the same correlation $\rho$ where $\rho \geq 0$. What's the pattern in generating this using linear combinations of the independent standard normal variables?

I know that for the $2$-dimensional case: given a correlation $\rho$ you can generate the first and second values, $ X_1 $ and $X_2$, from the standard normal distribution. Then from there make $X_3$ a linear combination of the two $X_3 = \rho X_1 + \sqrt{1-\rho^2}\,X_2$ then take  $$ Y_1 = \mu_1  + \sigma_1 X_1, \quad Y_2 = \mu_2 + \sigma_2 X_3$$  So that now $Y_1$ and $Y_2$ have correlation $\rho$.  How would this be scaled to $n$ variables? With the condition that the end variables satisfy a given correlation matrix? I'm guessing at least n variables will need to be generated then a reassignment through a linear combination of them all will be required... but I'm not sure how to approach it.


I need to create a grid over my QGIS shapefile, with 1m intervals. I know the procedure of creating the grid; view -> decorations -> grid  My question is, what is the x and y intervals that I need to provide in order to get a grid with 1 meter intervals, when I am creating a line grid?

How do I create a fishnet shapefile using QGIS?   The equivalent task of "Create Fishnet" in ArcGIS.


Was wondering if anyone can verify year of the Gitane frame  Thanks Damian

This is a canonical question that will hopefully encompass all of the questions we get asking us to determine what year a bicycle was manufactured (how old is my bike, how old is my frame, etc.). Each "answer" should address a different way to determine the manufacturing year of a bicycle. To some extent, these will also help you narrow down the model as well as it will tell you what distinguishing features to look at.  The span of answers would include things such as:      Skiptooth cranks Cartridge bottom brackets (BB30/90 etc) Elliptical chainring Quick releases versus contemporary through-axles How the steerer attaches to the fork (quill vs. threadless)  Braking system (especially with mountain bikes: v-brake, direct pull, etc.)   Shifting ramps and pins on cassettes/sprockets and chainrings (versus flat sprockets) Frame material (e.g., shift from tubular steel to use of CF and hydroformed aluminium)  Frame tubing type (e.g. Reynolds 531 tubing introduced around 1934, still used today; Reynolds 501 tubing introduced around 1983). So a frame with an original 501 decal can't be from the 70', 531 decal doesn't help as much because of the range of years produced. Also, see Decals.   *Decals: style/design, amount, placement, color, etc. can help not only determine models, but also year of manufacture. Many changed decal design for the same model bike often yearly, with special/limited editions even more specific. This applies only if decals are original or have been replaced with the identical design. Tubing decals (Reynolds, Columbus, etc.) also changed designs for same tubing made in different years, although the changes aren't made as often, and manufacturers didn't always put tubing Brand decals on every model. Earlier bikes tended to have less fancy, less colorful, less quantity of decals.   Headbadges: most early bikes had actual "badges", often quite detailed and fancy, made of metal, then plastic, and finally just using decals on the headtube. Most bikes lost their metal badges in the 60's and early 70's, although some brands still have actual badges to this day, but in general a real badge indicates an earlier model bike. Dropout style (including the later inclusion of lawyers lips) Presence or absence of CPSC reflectors (USA only) Manufacturing method (shift from lugs to TIG welding, for example)  Number of gears (shift from 2x5 ten-speed to 3x8, 2x9, 1x11, etc.)  Inspection of lug design: pantographs, cut-out, stampings, custom brazing/filing, chrome, fork crow n sweep, etc. Frame/Fork Braze-ons. Race bikes tended have less braze-ons the earlier the year of manufacture. Most 60's racers and earlier had few or none with cable guides/stops, shifters, bidons, etc. being clamp-on. By the 80's if it was clamp-on, it was a sign of very cheap models and most frames had braze-ons for all cables, with multiple bottle and accessory bosses depending on style and use.   and so forth. Please edit this question if you have an answer that isn't in the index above.   A couple of caveats:   A previous owner could have replaced or upgraded components on a bicycle, so this guide only applies to original equipment There is a delay between the introduction of a technology (such as indexed shifting) and when manufacturers start selling products that use it. Low-end manufacturers may continue using technology that is severely outdated (such as one-piece cranks, freewheels, or quill stems) because it is cheaper to do so. A number of bikes are built in a Retro style, but with modern components.  Dutch bikes, trendy coffee cruisers, and beach cruisers may be modern but appear to be 1950s styling.  These tend to have modern rims and brakes as a giveaway.     Note that bicycles.stackexchange does not do valuations of bicycles. How much your bicycle is worth depends on the location of the buyer and seller, how much the buyer wants the bike, etc. etc. etc.


I have a datetime in the following format: Wed, 03 September 2013 02:05:50 GMT  Now when i try to parse this string to a datetime object using a mask, i get a formatexception  DateTime parsed = DateTime.ParseExact("Wed, 03 September 2013 02:05:50 GMT", "ddd, dd MMMM yyyy HH:mm:ss zzz", CultureInfo.InvariantCulture);   I did check DateTime.Now with the above mask, and it matches the date i want to parse exactly. How can i parse this date?

I'm trying to parse an international datetime string similar to:  24-okt-08 21:09:06 CEST   So far I've got something like:  CultureInfo culture = CultureInfo.CreateSpecificCulture("nl-BE"); DateTime dt = DateTime.ParseExact("24-okt-08 21:09:06 CEST",     "dd-MMM-yy HH:mm:ss ...", culture);   The problem is what should I use for the '...' in the format string? Looking at the  MSDN page doesn't seem to list a format string for parsing timezones in PST/CEST/GMT/UTC form.


I have two layers, points and polygons. Point layer is empty. When I add new point feature I want to update it's field by values of polygon field if new point is within polygon. I need solution in QGIS.  How can I do this?

I am digitising line-features based on WGS-84 point-coordinates from a PDF which cannot be copied from.  The final line layer should contain lines which each connect two points and have the following attributes:   Name of start point - name of end point value in [ft] value in [m] remark (same for all features) date of creation   Currently I have a csv-based point layer which simply contains the name and coordinates of each point.    Creating the point layer is no problem, but creating the lines is a bit of a hassle. Either I manually create a .csv containing all existing connections between points like the following table and run connect by lines:    Or I digitise the lines manually but fill in the values (except for the value in [ft]) automatically.    Personally I would prefer option 2, since option 1 involves more manual work and the process has to be repeated regularly (and I figure I could transfer the solution to other tasks), but I can't get the expression right which should fill in the name of the line. All other values are created flawlessly (though they are not taken from another layer based on geometry).  I added the WKT of each point to the point-layer. Currently I am running the following, which returns NULL, despite it seems to be correct to me:  attribute(get_feature('point-layer','geom',geom_to_wkt(start_point($geometry))),'Waypoint')||' - '||attribute(get_feature('point-layer','geom',geom_to_wkt(end_point($geometry))),'Waypoint')   Any ideas where I went wrong?


Given two parallel planes: $$ ax + by + cz = d \\ ax + by + cz = e $$ How would I derive a formula for the distance between them?

The following show you the whole question.     Find the distance d bewteen two planes   \begin{eqnarray} \\C1:x+y+2z=4 \space \space~~~ \text{and}~~~ \space \space C2:3x+3y+6z=18.\\ \end{eqnarray}   Find the other plane $C3\neq C1$ that has the distance d to the plane $C2$.   According to the example my teacher gave me, the answer should be :     Am I right? However, I do not know what is normal and why there are P(5) and Q($-\frac{1}{2}$).    Thank you for your attention


Hey guys im new to Ubuntu so i installed Ubuntu 16.04 onto DOS OS of my HP.  Legacy support is Enabled.Security Boot Disabled in the BIOS Settings.  When i go to the additional driver i get nothing except the default Unknown one. The output i got after running iwconfig is eno1      no wireless extensions.  lo        no wireless extensions.  The ouput i got after running lspci -nn is 00:00.0 Host bridge [0600]: Intel Corporation Xeon E3-1200 v6/7th Gen Core Processor Host Bridge/DRAM Registers [8086:5914] (rev 08) 00:02.0 VGA compatible controller [0300]: Intel Corporation UHD Graphics 620 [8086:5917] (rev 07) 00:04.0 Signal processing controller [1180]: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem [8086:1903] (rev 08) 00:08.0 System peripheral [0880]: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th Gen Core Processor Gaussian Mixture Model [8086:1911] 00:14.0 USB controller [0c03]: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller [8086:9d2f] (rev 21) 00:14.2 Signal processing controller [1180]: Intel Corporation Sunrise Point-LP Thermal subsystem [8086:9d31] (rev 21) 00:16.0 Communication controller [0780]: Intel Corporation Sunrise Point-LP CSME HECI #1 [8086:9d3a] (rev 21) 00:17.0 SATA controller [0106]: Intel Corporation Sunrise Point-LP SATA Controller [AHCI mode] [8086:9d03] (rev 21) 00:1c.0 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express Root Port #5 [8086:9d14] (rev f1) 00:1c.5 PCI bridge [0604]: Intel Corporation Sunrise Point-LP PCI Express Root Port #6 [8086:9d15] (rev f1) 00:1f.0 ISA bridge [0601]: Intel Corporation Device [8086:9d4e] (rev 21) 00:1f.2 Memory controller [0580]: Intel Corporation Sunrise Point-LP PMC [8086:9d21] (rev 21) 00:1f.3 Audio device [0403]: Intel Corporation Sunrise Point-LP HD Audio [8086:9d71] (rev 21) 00:1f.4 SMBus [0c05]: Intel Corporation Sunrise Point-LP SMBus [8086:9d23] (rev 21) 01:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 15) 02:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. Device [10ec:d723]  Output after running rfkill list all is 0: hci0: Bluetooth     Soft blocked: no     Hard blocked: no PLEASE HELP !

I have not much experience with ndiswrapper but some vague memory of using it with some broadcom module long back. Now, here is the problem. Realtek RTL8723DE wireless module is used in my new HP 15-BS576TX laptop. I haven't installed Linux yet. But, would like to check if Ndiswrapper can help use the Windows driver to work in Linux. Here is the Windows 10/8/7 driver for this RTL8723DE wlan module:   I extracted the exe and can see a folder /RTWLANE_Driver/Wind7X86/ which has rtwlane.sys and few other files which I presume is related to the wireless driver. Is there any chances of luck with ndiswrapper considering the driver executable actually contains win8/win7 drivers.  Thank you.


When I am adding object offset to an array modifier he is not using original sizes instead he is transform my object and then add it.

I'm trying to make treads around a tire by applying an Array Modifier and using the Object Offset, but when I select object offset the tire tread it creates is squished in the X axis.  The offset object I am using is an empty plain axes, I've tried offsetting it to other objects and the same thing happened.


Are there any records of a Force-sensitive individual being born from non-Force-sensitive parents?  Do we have any information on whether Force-sensitivity is a genetic (or genetic-like) trait?  I am looking primarily for canon sources.

This has been discussed in at least one  before, but not directly addressed, at least not on this site.  Is there any actual connection between blood lines and Force sensitivity? We certainly see hints of that with both of Anakin's children showing Force sensitivity.  Do patterns like that show in other families?  Is there any indiction that Force sensitivity can be hereditary in some species or in some families?  (I'm not asking if it is always hereditary or always following blood lines, but is there enough to show this can be a notable factor in whether someone is sensitive or not.)


I'd appreciate it if someone explained everything regarding those three adjectives. They confuse me.

I've read both forms in newspapers and online news: elder brother and older brother. What's the difference between them? When should I use which?


-This address appeared in my win 10 proxy setting. Every time I turn it off it goes back on when I leave the proxy tab. -When this issue appeared I got an error in browser saying that there is no internet connection even do I can browse the web on any other device. -How can I fix this issue?

What should I do if my Windows computer seems to be infected with a virus or malware?  What are the symptoms of an infection? What should I do after noticing an infection? What can I do to get rid of it? how to prevent from infection by malware?   This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits.


Thanks again, everyone, for your huge help.  I am having some trouble finding a way to label all points on the 16-gon I have below.  Could someone give me a little help on how to do this without having to calculate every point?    I saw the post, , but I don't understand everything in the code well enough to see how to add the additional points to my illustration.  Thanks again.  \documentclass[11pt]{article} \usepackage[margin=1in]{geometry} \usepackage{amsfonts, amsmath, amssymb,} \usepackage[none]{hyphenat} \usepackage{tikz} \usepackage{pgfplots} \usepackage{pst-eucl} \usepackage[nottoc, notlot, notlof]{tocbibind} \usetikzlibrary{shapes.geometric} \begin{document}   \begin{center}  \begin{tikzpicture} \draw[thick](3,3) circle(4.25);   \node[ultra thick, red, draw,minimum size={2*4.25cm},regular polygon,regular polygon  sides=16,rotate=11.25] at  (3,3) (16-gon) {};          \fill [red] (3,3) +(90:4.25) circle (4pt);         \fill [red] (3,3) +(67.5:4.25) circle (4pt);         \fill [red] (3,3) +(112.5:4.25) circle (4pt);         \fill [red] (3,3) +(135:4.25) circle (4pt);         \fill [red] (3,3) +(157.5:4.25) circle (4pt);         \fill [red] (3,3) +(180:4.25) circle (4pt);         \fill [red] (3,3) +(202.5:4.25) circle (4pt);         \fill [red] (3,3) +(225:4.25) circle (4pt);         \fill [red] (3,3) +(247.5:4.25) circle (4pt);         \fill [red] (3,3) +(269.5:4.25) circle (4pt);         \fill [red] (3,3) +(292.5:4.25) circle (4pt);         \fill [red] (3,3) +(315:4.25) circle (4pt);         \fill [red] (3,3) +(337.5:4.25) circle (4pt);         \fill [red] (3,3) +(360:4.25) circle (4pt);         \fill [red] (3,3) +(382.5:4.25) circle (4pt);         \fill [red] (3,3) +(405:4.25) circle (4pt);            \node[thick, red] (n1) at (-.5,-.5) {\begin{huge}$A$\end{huge}};          \node[thick, red] (n1) at (-.5,6.5) {\begin{huge}$E$\end{huge}};          \node[thick, red] (n1) at (6.5,6.5) {\begin{huge}$I$\end{huge}};          \node[thick, red] (n1) at (6.5,-.5) {\begin{huge}$M$\end{huge}};          \node[thick, red] (n1) at (-1.9497,3) {\begin{huge}$C$\end{huge}};          \node[thick,red] (n1) at (3,7.9497) {\begin{huge}$G$\end{huge}};          \node[thick, red] (n1) at (7.9497,3) {\begin{huge}$K$\end{huge}};          \node[thick, red] (n1) at (3,-1.9497) {\begin{huge}$O$\end{huge}};   \end{tikzpicture} \end{center}  \end{document}

Consider the slight modification of the construction from the solution to this question:   \documentclass{minimal} \usepackage{tkz-euclide} \begin{document}  \begin{tikzpicture}[scale=3] \tkzDefPoint(0,0){O} \tkzDrawCircle[R](O,1 cm) \def\sectors{20} \foreach \i in {1,2,...,\sectors} {     \tkzDefPoint({\i*360/\sectors}:1){P\i}        \tkzDrawSegment[color=black](O,P\i)     \tkzLabelPoint(P\i){\i} %modified here! } \end{tikzpicture} \end{document}   This gives me the following output:    Now my question is, if it is possible to position the labels in extension of the radial lines.   Is it possible to rotate the labels additionally corresponding to the orientation of the respective radial line? (so that for example the 5  on my output would be rotated by 90° counter-clockwise).


I have installed 2 instances of sql server plus SSIS on the following server.  Note the amount of RAM is nearly 384 GB      And this is the max and min memory settings that I have applied to my 2 instances. I assume that both instances will use equal amount of resources, if that would really be the case, 184,320 MB which is 180 GB be a good starting number to set up my memory?  How much memory would I allocate to SSIS?

Is SSIS subject to the maximum memory limitations for SQL Server 2012 Standard edition?  If I have a server with 128GB RAM and I allocate 64GB of RAM to SQL Server does SSIS utilise this memory or does it utilise the memory that is available to the OS?  I am assuming it utilises the remaining memory left to the OS since there is no settings for memory consumption and it runs as a separate service.  If anyone has any information on the available memory that should be left for SSIS to consume I would appreciate the help.


I am unsure of this rule, and would like a straight answer or resource; this is not a peeve. This appears today in google trends:  A new set of icons suggest that voice-activated sharing to social networks could be on the cards. Should not the proper term be suggests since the subject is actually 'set' not 'icons'?  Read more:

That's a lot of cars!   Those are a lot of cars!      The context is when a someone sees many objects (in this example, cars) and makes the exclamation.   According to , lot can handle either singular or plural verbs.  I agree with the author who states that that's sounds better, but the post doesn't seem definitive either way.     Are both grammatically correct and do they have the same meaning?


public class Abc {    public static void main(String args[])    {       def obj=null;       obj.method();     } } class Def {    void method()    {        System.out.println("class def->>> method()");    } }   The output of this code is generating a NullPointerException and why?

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


Today’s (May 7) New York Times carries an article under the title, “Issues, schmissues. Can the Presidential candidates sing?,” which begins with the following passage:  “The cacophony of presidential candidates is getting louder by the day, and while they have a variety of views on political matters, many of them have at least one thing in common — a love of music.” -   I consulted with Oxford online English Dictionary and Cambridge online English Dictionary to get the meaning, neither of which carries the definition of the word, “Schmissues.*”  I presume “schmissues” is an Yiddish origin from its sound. What does it mean? Is the word popular among Americans?  *P.S. I should have checked "schm-," not “Schmissues.”

There is a curious construct in American English in which a word is stated and then repeated with the prefix "schm-" or "shm-" in order to indicate the speaker's dismissive attitude toward a concern that somebody else has. For example:     "Smokers have lower life expectancies? Correlation, schmorellation—I'm going outside for another cancer stick."   Is the commoner or more "correct" spelling "shm-" or "schm-"? Is this construction used outside the US? What is its origin?


Should I write it like this? Or perhaps like this? Should I write it like this? or perhaps like this?   What about after an exclamation mark or semicolon?

May I use a question mark in the middle of a sentence? Examples:  Would you like the drapes to be white? or perhaps something off-white? Would you like the logo to be centered? at the bottom? left off entirely?


Example: A commute planer app could take a start and destination from you, through Siri, and plan your trip. Would be very useful, especially when you're in a hurry.

Could YouTube, Todoist, myEmail (fill in name app your looking for) be controlled/used with Siri?  Could a third party iOS app be controlled by Siri?


The below is my macOS version with basic capabilities :     While developing my apps, my Mac often shows great memory usage and swaps. These makes my Mac running and building apps slowly.  I would like to find out the ways to increase my SSD capacities and RAM . Would you please tell me how can I upgrade my RAM and SSD?

I know that the new rMBPs have no "user-serviceable" RAM. But is it possible to solder a new RAM chip onto a 2015 rMBP? Given that the technician doing this is able to install the new chip without damaging anything, would it work?


Got a Magikarp the other day with 150CP and 39 HP. With 20/15 IV I thought it was an ok magikarp to evolve (I'm a collector, not a fighter..) But since I had some candy extra, I tought I'd like to power it up a bit first. When I power up, the CP went down from 150 to 132 and the HP down to 34. Surprised I powered it back up to 150, but now it only have a HP on 37. What just happened?

As of yesterday, November 21, 2016, . Which ones had their CP changed?


A gambler rolls two unbiased dice and stands to loss of $ \$2$ if he fails to throw a six, to win $ \$4$ if he throws one six and to win $ \$10$ if he throws two sixes. Is the game fair?  I can find probability for all three cases but to decide whether game is fair or not? Could someone help me with this?

Suppose $X_n$ is the fortune of a gambler after $n$ th game. Then the game is called fair (Breiman 1968) if   $$E[X_{n+1} \mid X_1, \dots, X_n] = X_n \forall n$$  My question is why a fair game is not defined as the following   $$E[X_{n+1}] = E[X_n] \forall n$$ i.e. $$E[X_{n+1}- X_n]=0$$. This should be the proper definition as a fair game is where avg. gain is zero. Nothing conditioning should be there.


My question iv very obvious: There are how many Lie algebras of dimension $3$ up to isomorphism?  I studied many texts but not getting a single word answer, plesae tell me about this.

I am reading the notes of Victor Kac (Introduction to Lie Algebras). After Cartan's theorem there is an  application, the classification  (up to isomorphism) of 3-dimentional Lie algebras.  We use the Cartan's theorem to write   $$ \mathfrak{g} = \bigoplus_{\lambda\in \mathbb{F}}\mathfrak{g}^{a}_{\lambda} $$  where $a \in \mathfrak{g}$ is a regular element and $\mathfrak{h}=\mathfrak{g}_{0}^{a}$ is a subalgebra de Cartan.  I have proven when $\mbox{rank }\mathfrak{g}=\dim\mathfrak{h}=1$ one has  3 possibilities for $\mathfrak{g}=\mbox{span}\{a,b,c\}$:  \begin{eqnarray} 1 &-& [a,b]=b, [a,c] = c + b, [b,c] = 0\\ 2 &-& [a,b]=b, [a,c] = \lambda c, [b,c] = 0, \mbox{ for a non null $\lambda$} \\ 3 &-& [a,b]=b, [a,c] = -c, [b,c] = a \end{eqnarray}  So my question is: How proof that these 3 Lie algebras are non isomorphic?  I would be happy with any help!


In PostGIS I have three tables table1, table2 and table3 of same type: CREATE TABLE tableX (     myid integer NOT NULL,     wkb_geometry geometry(LineString,4326) )  table1 and table2 are populated. I want to intersect the linestrings of table1 and table2 and insert the result into table3 like this: insert into table3 (     select         table1.myid,         ST_Intersection(table1.wkb_geometry, table2.wkb_geometry)     from table1, table2 )  The result of ST_Intersection() is sometimes of type LineString and sometimes of type MultiLineString. Therefore I am getting an error: ERROR:  Geometry type (MultiLineString) does not match column type (LineString)  And if I change the geometry type of table3 to MultiLineString I am getting the opposite error: ERROR:  Geometry type (LineString) does not match column type (MultiLineString)  What is an elegant way to store the results of this intersection, but preserving the original information if the intersection was LineString or MultiLineString? Is there no 'flexible' geometry type for columns which could hold results of both types? ( If possible I do not want to normalize the results with ST_Multi, because later I would need to decompose with ST_Dump )

I run PostgreSQL 9.1 and PostGIS 2.0. I have a table that contains one geometry column.   But that column contains point, polygons lines, etc.   So I set it like so,   ALTER TABLE jake ADD COLUMN jake_geom geometry;  and then I setted some constraints to make it geometry enabled, but not limited on a single geometry type  ALTER TABLE jake   ADD CONSTRAINT enforce_dims_geom CHECK (st_ndims(jake_geom) = 2);  ALTER TABLE jake   ADD CONSTRAINT enforce_srid_geom CHECK (st_srid(jake_geom) = 900913);   Now, I want to reproject the geometries in that column to 4326.   According to , for the transform to work, I need to set a geometry type.  (the TYPE geometry(MultiPolygon,2163) part)  but my column does not have certain geometry type. How do I proceed?  Or I can simply do  ALTER COLUMN geom USING ST_Transform(geom,2163);  avoiding to set a type?


I'm trying to install Acrobat reader on Ubuntu latest version. I followed the step by step instructions in , but when I try to execute the wine commands   wine AcroRdrDC1800920044_en_US.exe   I got the following error:   it looks like wine32 is missing, you should install it. as root, please execute "apt-get install wine32" it looks like wine32 is missing, you should install it. as root, please execute "apt-get install wine32" wine: Mauvais format EXE pour Z:\home\morad\Téléchargements\AcroRdrDC1800920044_en_US.exe.    Can anyone help me to fix this issue? Thanks in advance.

In Ubuntu, I want to open a PDF document generated for Adobe Reader 10. Apparently the latest version which I can install is Adobe Reader 9.5.5. Is there a way to install version 10?  I installed Wine, but I don't know how to install acroread using Wine.


I'm using Xubuntu and upgraded to 13.10 as the system dialog suggested it. However, after rebooting and logging in (the Loginscreen still perfectly works), I only see a black Desktop with an invisible mouse cursor, and my taskbar on the bottom. The invisible mouse is still useable as onMouseOver Effects apply.  After searching through the internet for a solution (the Guest Login still perfectly works), it seemed like the ATI drivers may be the root of evil here and it had been suggested to remove all fglrx packages and continue with the open source driver.  After uninstalling fglrx and rebooting, I'm experiencing exactly the same issues as mentioned in this question:   No Taskbar, no Mouse, just the plain Desktop Background. The problem at this point, however, is, that I use Xubuntu and xfce and none of the solutions of the mentioned thread was applicable for me so far as I don't have unity or compiz.

When I login, nothing happens.   I am presented with my desktop wallpaper.    No Dash, no Launcher, nothing.


Let $K$ be an extencion of $F$ and let $a,b\in K$. If $a$ is not algebraic in $F$, but it is in $F(b)$, show that $b$ is algebraic in $F(a)$.   $F(x)$ is the smaller subfield of $K$ containing $F$ and $x$.  I'm not used to problem abouth field extentions and algebraic numbers, I just know the definition, so I need some help with this problem. Thanks.

If $v$ is algebraic over $K(u)$ for some $u\in F$, $F$ is an extension over $K$, and $v $ is transcendental over $K$, then $u$ is algebraic over $K(v)$.  I came across this problem in the book Algebra (Hungerford), I feel it shouldn't be too hard but I just can't work it out. Hope you can help me. Thank you!


My application is intended to read an existing text file, line for line, of exactly 1500 items into an array of item class objects. The goal is to get the data into the array so I can use this application as a starting point for converting the archive for a new program I am writing.  package sandboxPackage;  import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader;  public class mainClass {     public static void main(String[]args) throws FileNotFoundException, IOException {     InputStream in = new FileInputStream(new File("C:\\Documents and Settings\\Adam\\Desktop\\Cloud Project\\MasterIndex.library"));     BufferedReader reader = new BufferedReader(new InputStreamReader(in));     StringBuilder out = new StringBuilder();     String line;     itemClass[] m = new itemClass[1500];     int i = 0;     while ((line = reader.readLine()) != null) {         m[i].index = line;       // crash is here         m[i].location = reader.readLine();         m[i].item = reader.readLine();         m[i].description = reader.readLine();         i++;     }      //Print the entire list     for (i = 0; i == 1499; i++) {         System.out.println(m[i].index);         System.out.println(m[i].location);         System.out.println(m[i].item);         System.out.println(m[i].description);         //System.out.println("This is item #" + i + 1);     }      } }   And here is the itemClass:  package sandboxPackage; public class itemClass{     String index;     String item;     String description;     String location; }   The text file looks like this: Index Location Item Description Index Location Item Description Index ..  The compiler claims the NullPointerException is on line 20, which is the first line of the while loop, but I just don't see it. I have looked at about a thousand other examples of this same error but it still does not compute for me.

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


Are there infinitely many primes $p$, such that,  $p-1=n^2$ where $n\in \mathbb{N}$.  As $p$ must be $odd$, we can say that $p$ must be of the form $4k+1$. But I do not know how to proceed.

I met a student that is trying to prove for fun that there are infinitely many primes of the form $n^2+1$. I tried to tell him it's a hard problem, but I lack references. Is there a paper/book covering the problem? Is this problem really hard or I remember incorrectly?


A long time ago, I learned that the URL https://<S.E site>/search?q=user%3A<my user numbe>+closed%3A0+hasaccepted%3A0+answers%3A1+wiki%3A0&submit=search (user:XXX closed:0 hasaccepted:0 answers:1 wiki:0) shows all of my questions on a S.E site which I have not yet answered. I imagine that lots of users would not know of this and how to do it for their own questions, would like to know it, and would like it to be simpler to do. Would it be possible to add something like a button on my profile page, visible only to me, obviously, to show this? I don't really care how it is implemented, so long as it is easily accessible. If possible, I would like it both per site and S.E-wide. Or did I miss something, and this is already available? Not sure if it's for everyone, but I would be happy with a nagging email ("you haven't answered that question that you asked X days ago").

I've been asking quite a few questions on several Stack Exchange sites, and I'm finding it harder and harder to keep track of them all.    Is there any way/place to see a listing of all my questions with no answer accepted on all of the Stack Exchange (2.0) sites? Or even just per site? If not, are there any plans to implement such a feature?  Although Jeff offered an answer, I don't feel it's the answer to my question; as far I'm aware there still is no way to list only my unanswered questions.


How can we know that a black hole exists if it attracts both matter and light, and to prove that it exists would need to observe it?  It's a very common question but I don't know the answer.

I'm not very knowledgeable about physics generally, but know that nothing can escape a black hole's gravitational pull, not even light (making them nearly invisible?).   My question is: What has been obtained from direct observation of a black hole to prove their existence? Please note that I'm not questioning the existence of black holes, but am just curious as to how we have come to realize it.


#include<stdio.h>  void main() {     int a = 4;     switch (a)     {         case 4:             int res = 1;             printf("%d",res);         break;      } }  When I compiled this code with gcc I got error root@ubuntu:/home/ubuntu# gcc test.c -o t test.c: In function ‘main’: test.c:9:4: error: a label can only be part of a statement and a declaration is not a statement     int res = 1;  But when I add ; like case 4:; I can compile my code. What is the problem and why ; fix that?

I've always wondered this - why can't you declare variables after a case label in a switch statement?  In C++ you can declare variables pretty much anywhere (and declaring them close to first use is obviously a good thing) but the following still won't work:  switch (val)   {   case VAL:     // This won't work   int newVal = 42;     break; case ANOTHER_VAL:     ...   break; }     The above gives me the following error (MSC):     initialization of 'newVal' is skipped by 'case' label   This seems to be a limitation in other languages too.  Why is this such a problem?


They say that gravity is technically not a real force and that it's caused by objects traveling a straight path through curved space, and that space becomes curved by mass, giving the illusion of a force of gravity.  That makes perfect sense for planetary orbits, but a lot less sense for the expression of gravity that we are the most familiar with in our day-to-day lives: "what goes up must come down."  Imagine that I hold a ball in my hand, several feet off the ground, with my fingers curled around it, and my hand is above the ball.  Then I open my fingers, releasing my grip on it, being very careful to not impart any momentum to the ball from my hand as I do so.  An object at rest remains at rest unless acted upon by an outside force.  If the ball is not moving (relative to my inertial reference frame), it has no path to travel that's any different from the Earth's path through space.  It should remain at rest, hanging there in the air.  And yet it falls, demonstrating that an outside force (gravity) did indeed act upon it.  How does curved space explain this?

It is fine to say that for an object flying past a massive object, the spacetime is curved by the massive object, and so the object flying past follows the curved path of the geodesic, so it "appears" to be experiencing gravitational acceleration. Do we also say along with it, that the object flying past in reality exeriences NO attraction force towards the massive object? Is it just following the spacetime geodesic curve while experiencing NO attractive force?  Now come to the other issue: Supposing two objects are at rest relative to each other, ie they are not following any spacetime geodesic. Then why will they experience gravitational attraction towards each other? E.g. why will an apple fall to earth? Why won't it sit there in its original position high above the earth? How does the curvature of spacetime cause it to experience an attraction force towards the earth, and why would we need to exert a force in reverse direction to prevent it from falling? How does the curvature of spacetime cause this?  When the apple was detatched from the branch of the tree, it was stationary, so it did not have to follow any geodesic curve. So we cannot just say that it fell to earth because its geodesic curve passed through the earth. Why did the spacetime curvature cause it to start moving in the first place?


Find the least squares estimator of the parameter B (beta) in the following regression model: y= B + u What is the variance of the estimator?

I realize that this is a very basic question, but I can't find an answer anywhere. I'm computing regression coefficients using either the normal equations or QR decomposition.  How can I compute standard errors for each coefficient?  I usually think of standard errors as being computed as: $SE_\bar{x}\ = \frac{\sigma_{x}}{\sqrt{n}}$ What is $\sigma_{x}$ for each coefficient?  What is the most efficient way to compute this in the context of OLS?


We have a dataset with three variables (dV: self-reported measure on scale 1-5, assumed to be metric; iV1: factor with 4 levels; iV2: factor with 8 levels). We are interested whether the dV differs in regard to both iVs and whether there is an interaction between the iVs.  Idea: Calculating an ANOVA with both main effects and the interaction between both iVs using R.  The question: What Type of Sum of Squares should be used for this research question?  Using aov() in R calculates Type-I Sum of Squares as standard. SPSS and SAS, on the other hand, calculate Type-III Sum of Squares by default. However, using Anova() {car} in combination with options(contrasts=c("contr.sum", "contr.poly")) in R gives the same Type-III ANOVA tables as calculated in SPSS.  I have already read the following discussions:       However, I am still confused which Type of Sums of Squares is the most adequate for our question. The results (F and p values) differ considerably.

My primary question is how to interpret the output (coefficients, F, P) when conducting a Type I (sequential) ANOVA?   My specific research problem is a bit more complex, so I will break my example into parts. First, if I am interested in the effect of spider density (X1) on say plant growth (Y1) and I planted seedlings in enclosures and manipulated spider density, then I can analyze the data with a simple ANOVA or linear regression. Then it wouldn't matter if I used Type I, II, or III Sum of Squares (SS) for my ANOVA. In my case, I have 4 replicates of 5 density levels, so I can use density as a factor or as a continuous variable. In this case, I prefer to interpret it as a continuous independent (predictor) variable. In R I might run the following:  lm1 <- lm(y1 ~ density, data = Ena) summary(lm1) anova(lm1)   Running the anova function will make sense for comparison later hopefully, so please ignore the oddness of it here. The output is:  Response: y1           Df  Sum Sq Mean Sq F value  Pr(>F)   density    1 0.48357 0.48357  3.4279 0.08058 . Residuals 18 2.53920 0.14107    Now, let's say I suspect that the starting level of inorganic nitrogen in the soil, which I couldn't control, may have also significantly affected the plant growth. I'm not particularly interested in this effect but would like to potentially account for the variation it causes. Really, my primary interest is in the effects of spider density (hypothesis: increased spider density causes increased plant growth - presumably through reduction of herbivorous insects but I'm only testing the effect not the mechanism). I could add the effect of inorganic N to my analysis.   For the sake of my question, let's pretend that I test the interaction density*inorganicN and it's non-significant so I remove it from the analysis and run the following main effects:  > lm2 <- lm(y1 ~ density + inorganicN, data = Ena) > anova(lm2) Analysis of Variance Table  Response: y1            Df  Sum Sq Mean Sq F value  Pr(>F)   density     1 0.48357 0.48357  3.4113 0.08223 . inorganicN  1 0.12936 0.12936  0.9126 0.35282   Residuals  17 2.40983 0.14175    Now, it makes a difference whether I use Type I or Type II SS (I know some people object to the terms Type I & II etc. but given the popularity of SAS it's easy short-hand). R anova{stats} uses Type I by default. I can calculate the type II SS, F, and P for density by reversing the order of my main effects or I can use Dr. John Fox's "car" package (companion to applied regression). I prefer the latter method since it is easier for more complex problems.  library(car) Anova(lm2)             Sum Sq Df F value  Pr(>F)   density    0.58425  1  4.1216 0.05829 . inorganicN 0.12936  1  0.9126 0.35282   Residuals  2.40983 17     My understanding is that type II hypotheses would be, "There is no linear effect of x1 on y1 given the effect of (holding constant?) x2" and the same for x2 given x1. I guess this is where I get confused. What is the hypothesis being tested by the ANOVA using the type I (sequential) method above compared to the hypothesis using the type II method?  In reality, my data is a bit more complex because I measured numerous metrics of plant growth as well as nutrient dynamics and litter decomposition. My actual analysis is something like:  Y <- cbind(y1 + y2 + y3 + y4 + y5) # Type II mlm1 <- lm(Y ~ density + nitrate + Npred, data = Ena) Manova(mlm1)  Type II MANOVA Tests: Pillai test statistic         Df test stat approx F num Df den Df  Pr(>F)     density  1   0.34397        1      5     12 0.34269     nitrate  1   0.99994    40337      5     12 < 2e-16 *** Npred    1   0.65582        5      5     12 0.01445 *    # Type I maov1 <- manova(Y ~ density + nitrate + Npred, data = Ena) summary(maov1)            Df  Pillai approx F num Df den Df  Pr(>F)     density    1 0.99950     4762      5     12 < 2e-16 *** nitrate    1 0.99995    46248      5     12 < 2e-16 *** Npred      1 0.65582        5      5     12 0.01445 *   Residuals 16


I have looked long and hard for this, but can't find exactly what I'm looking for. I want to edit videos on my Linux computer because of how much better the software is for editing. I record videos on my Windows computer which are mostly tutorial videos using an Elgato capture card these files are very big.    The question is: How can I set up a wireless file transfer from Windows to Ubuntu?

I wanna transfer some files from this PC with Ubuntu to a PC with Windows 7 I don't care how to do it (ftp, samba or whatever) I wanna know the steps, I searched a lot but I can't find anything that works. Thank you.


I need to create a json payload to send data in this format {    "ids":[       "6375502",        "637550",       "6376391"    ],    "type":"MrnId",    "extId":"104DC758-25AE-47A8-931A-DD9DC1637049" }  How should I write the payload? One sample is below - var payload = '{"ids":arr,"type":"MrnId",    "extId":"104DC758-25AE-47A8-931A-DD9DC1637049"}';  here arr is the array of ids

This is a canonical question and answer developed by the community to help address common questions. If you've been directed here, or your question has been closed as a duplicate, please look through the resources here and use them to shape more specific questions. To browse all canonical questions and answers, navigate to the  tag.  This question and answer is owned by the community! If you can improve it and make it more useful, you're welcome to edit it.  I have a specific JSON structure in mind. I need to either deserialize this structure that's coming in from a web service, or I need to serialize data into this structure to transmit it to another system. How should I get started on this project in Apex?


I was just wondering if it's possible to search for specific keywords in a Facebook wall of a certain page.  I found  but it is 3 1/2 years old now so I thought things might have changed.  Can this be done?

I once liked one text post from one FB Page without clicking its like button (because basically I like every text post from this page).  Now, I have to refer that text post in my writing, but the thing is I forgot which post that has that text keyword, I tried searching that keyword by including the name of my FB Page and the keyword on the Search textbox at the right of Facebook's Earth icon, but that didn't work.  How can I search a text keyword in a Facebook Page? So that I can get its post, the one and only, just like when I got a twitter status that has the text keyword I searched.


I am getting a new desktop soon and wanted to know if Ubuntu is compatible with my build. I will be using it to play Minecraft on high settings with shaders enabled. Here is the complete list of hardware.  CPU- AMD FX 6300 3.5Ghz 6-Core  Mobo- Gigabyte GA-970A-UD3P ATX AM3+ Motherboard  GPU- Sapphire Radeon R9 270X 2GB Vapor-X Video Card  RAM- G.Skill Ripjaws X Series 16GB (2 x 8GB) DDR3-1866 Memory  Storage- Sandisk SSD PLUS 120GB 2.5" Solid State Drive  Power Supply- Rosewill 750W 80+ Bronze Certified ATX Power Supply  Case- Cooler Master Elite 431 Plus (Black) ATX Mid Tower Case  Mouse- UtechSmart Venus 50 to 16400 DPI High Precision Laser MMO Gaming Mouse for PC  I will be displaying it on my 32" Samsung 1080p HDTV. I had Ubuntu on an old Core 2 Duo HP desktop and loved it, if this build is compatible with Ubuntu then I don't need to worry about getting another copy of windows for my new build.  If you need more info, please let me know!

I am a bit financially strapped and received a Gateway GT5056 tower. The tower has an AMD dual core 64-bit processor in it. Will Ubuntu 12.04 run on this machine? I will not have any other application other than LibreOffice installed.


I would like to use pgfplots to create a figure where I plot curves that have a recursive formula. I tried a very simple case that uses the declare function command to see whether this is possible, and I can't compile (TeX capacity exceeded). Is it even possible to do this?  \documentclass{standalone}  \usepackage{pgfplots}  \begin{document}  \begin{tikzpicture}[   declare function={test(\p)=ifthenelse(\p>1, test(\p-1), 0.5);}, ]     \begin{axis}[]     % use TeX as calculator:     \addplot [mark=none] {x};     \addplot [mark=none] {test(0)};     \end{axis} \end{tikzpicture}  \end{document}

Is it possible to plot a recursive function using pgfplots \addplot command?  I tried like this;  \documentclass{article} \usepackage{pgfplots}  \pgfmathdeclarefunction{fac}{1}{   \pgfmathparse{(#1<=1)+                 (#1>1)*#1*fac(#1-1)   } }  \begin{document} fac(5) is \pgfmathparse{fac(5)}\pgfmathresult  \end{document}   But the result seems to be an infinite recursion, as the entire function is being evaluated.


I'm building a Visualforce page with some JavaScript to build a content DataTable based off the following example:   This page works well and looks great in Salesforce, but when I try to open it in the community it looks like the JavaScript is not working. The page references the same public static resource file, so I'm not sure why this would work in Salesforce and not the community.  Any help would be greatly appreciated.   Edit: This question is NOT a duplicate of the one listed. As I said, I set the static resource to public.   Thanks!

Pretty simple question. I have a VisualForce Page on which I have the following line:  <apex:stylesheet value="{!URLFOR($Resource.MyStyleSheet)}" />   When I access this page via a SiteIt's not loading, and when I look in the console I see this error:     Failed to load resource: the server responded with a status of 404 (Not Found)   Do I just have to inline everything?


Let $p \geq 3$ be a prime number.  How to prove that $(p-3)!+2^{p-2} \equiv 0 \ (\mathrm{mod} \ p)$?  My idea was to use Wilson's theorem:  Since $p$ is a prime it follows that $(p-1)! \equiv -1 \ (\mathrm{mod} \ p)$.  $\Rightarrow 1 \cdot \cdot \  \cdot (p-2)(p-3)+2^{p-2} \equiv -1 \ (\mathrm{mod} \ p)$  Then $1 \cdot \cdot \  \cdot (p-2)(p-3)+2^{p-2} +1 \equiv 0 \ (\mathrm{mod} \ p)$  Now I'm not sure what to do next. Is this way right or how can it be shown correctly?

Suppose that $p$ is a prime. Suppose further that $h$ and $k$ are non-negative integers such that $h + k = p − 1$.   I want to prove that $h!k! + (−1)^h \equiv 0 \pmod{p}$  My first thought is that by Wilson's theorem, $(p-1)! \equiv -1 \pmod{p}$, and $h!k!$ divides $(p-1)!$ (definition of a binomial). Where would I go from here?


I have recently started learning about tensors during my course on Special Relativity.  I am struggling to gain an intuitive idea for invariant, contravariant and covariant quantities.  In my book, invariant quantities are described as being those physical quantities associated with a point in space e.g. temperature at point P.  Thus, when changing coordinate system, the value associated with the point is unchanged: you may represent the point by a different set of coordinates, but on locating the point in the new coordinates, the temperature value will still be the same. Here comes my struggle: the archetypical example of a covariant quantity is the gradient vector.  Is it not the case that we require it to transform between coordinate systems in a way that preserves the vector associated with each point? Thus, in a way, the gradient vector is an invariant quantity?  Why then are many derivations in my course driven by the fact that physical quantities like Action, Lagrangians etc should be "Lorentz invariant"?

I have a pretty good knowledge of physics, but couldn't deeply understand what a  is and why it is so fundamental.


In sentences such as:     We could go down to the fishing village, just ______ we used to.   Is there a right or wrong preposition to use, between "as" and "like"?  What would be the difference?

I know that like is a preposition but why not using it as conjunction?  Examples:        It's as if I'm walking on air   It's like I'm walking on air      What is the difference?


I just upgraded my graphics card from  to .   Is there any advantage in leaving the 1660-Ti in? The 2070 has shown a 30% increase in benchmark so far!

I have a GTX 1060 6GB in my current build, and I also have a GTX 960 2GB in storage. I was wondering if I got , and got both of my GPUs in one build (not SLI or CrossFire, just in the same system) would I be able to use both GPUs for rendering simultaneously? I don't care if this means having them both render separate tiles in one instance of Blender, or rendering separate frames in two instances. I'm using Cycles for everything I do.


I am working on a login for my USB. I know there are other languages that do that better but I am learning Java. I get an error using the IO Console package access; import java.awt.Desktop; import java.io.*;   public class access {      public static void main(String[] args)throws IOException {         BufferedReader reader = new BufferedReader (new InputStreamReader (System.in));                  Console c = System.console();                   Desktop desktop = Desktop.getDesktop();         File dirToOpen = null;                           String user = c.readLine("Username: ");                  char pass[] = c.readPassword("Enter password: ");         String uPass = new String(pass);                                 if(user.equals("yuto") && uPass.equals("abascalesgay")) {                          try {                 dirToOpen = new File("E:\\encrypted");                 desktop.open(dirToOpen);             }                          catch (IllegalArgumentException iae) {                 System.out.println("File Not Found");             }                              }         else {             System.out.println("Credenciales no válidas we, vuelve a intentarlo.");         }     }  }  Error log  Exception in thread "main" java.lang.NullPointerException     at access.access.main(access.java:17)

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


In The Lost World: Jurassic Park there is a scene where the ship which brings the T-Rex to San Deigo has no crew inside it. How come all the crew members are dead if the dinosaur was still inside the cage?

In Jurassic Park: The Lost World, a T-Rex is captured from the island, sedated, and put on a boat for the mainland.  During the trip to the mainland, the T-Rex got free and killed everyone.  When the boat arrives, our intrepid heroes find that in the ship's control room, there are body parts.  How did the T-Rex manage to kill people in that room?  All of the doors look smaller than the T-Rex's head, so how did she eat them?


"We don't serve their kind here."  The bartender at the Mos Eisley Cantina makes it clear to Luke that Threepio and Artoo have to wait outside. With such upstanding citizens as the Jawas around, I know I wouldn't feel safe leaving my droids unattended.  Why then does the bartender (or possibly his employer) think it's okay to make potential customers leave their droids outside? What is the rationale?

When —the bartender at the Cantina at Mos Eisley spaceport in the first Star Wars—says:     “We don’t serve their kind here.”   In reference to C-3PO and R2-D2 entering the bar, it’s certainly a bit prejudicial, but are these commonly held views in this universe? We don’t see it happen anywhere else in the films but is it implied elsewhere?


I installed Ubuntu 14.04 on my desktop It's an Intel Pentium 4 processor (Single Core) at 2.80Ghz, 1GB RAM, and for the Graphics its Intel 865G x86/MMX/SSE2 OS is 32 bit.  Boot up is quick and fast, but running anything is slow, it fades in/out slow. I did have 9.4 Jaunty installed but I figured why not upgrade to the latest version. Big mistake. :P  Windows 7 Operated faster than this on this desktop. ahaha.   Is there anyway it could just be graphics? I'm new to this version, but I've used 8,9, and 12, and I found that 12 thus far has been nice to use. But would LOVE to try this Version.  I do have a laptop (Using right now)  It's a Dell Inspiron 1501 (Yes my computers are old, but the laptop I got for free and the desktop I got for $40. :P) 3GB DDR2 RAM, AMD Turion 64 X2 2.00GHz, ATI Radeon Xpress, which is running Windows 7 Ultimate x86.   Would 14.04 benefit on the laptop? :P  Thanks. :)

For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?


I have a typical linear regression model: Y = B0 + B1*X1 + B2*X2  where B0, B1 and B2 are the regression coefficients which I solve for.  Before I do any regression modeling, I standardize the predictor variables X1 and X2. I also standardize the dependent(outcome) variable Y.  X1_standardized = (X1 - X1_mean) / X1_std X2_standardized = (X2 - X2_mean) / X2_std Y_standardized = (y - y_mean) / y_std  I would like to use the standardized values for my regression, however, to improve interpretation, I would like to revert (or de-standardize) the beta coefficients after solving for them.  How can I do this?

Namely, what is the calculation for determining the unstandardized (metric) intercept?  In my situation, all of the variables were standardized including the independent variable.  Therefore the formulas given in this post do not apply:   Rather the formulas given in this link () do. Specifically, this one:   B' = B * Sx / Sy   Where B' is the standardized coefficients.  So the reverse of that is:  B = B' * Sy / Sx   I confirmed that do be the case.  set.seed(1) d=data.frame(y=1:100,x1=runif(100)+10,x2=rnorm(100)+10) d$y=1+ 2 * d$x1 + 3*d$x2 ##easy coef 1 2 3 d0=d m=lm(y~.,d0) coef(m) #are 1 2 3 d=as.data.frame(scale(d)) m=lm(y~.,d) coef(m) #now: -1.575657e-17  1.834809e-01  9.668451e-01 coef(m)['x1']*sd(d0$y)/sd(d0[['x1']]) #nicely back to 2 coef(m)['x2']*sd(d0$y)/sd(d0[['x2']]) #nicely back to 3   However, what is the equation to determine the metric intercept?


How can I export 3D geometry object/scene, camera and textures to a .3DS format? I tried importing the file I created into 3DsMax but it didn't work properly.

I have motion tracked my camera in Blender and have been trying to import it into 3d max. When I export it as an .fbx, the camera, when I import it into Max,  is facing the opposite direction to what it was in the Blender scene, and the animation that was on the camera, is on the geometry. I tried to change the forward axis of the camera in the export settings but this didn't effect the direction of the camera at all when I brought it into Max.   I tried an .obj, but only the geometry imported and it was all squashed together, and the camera didn't import at all.  So then I tried to export as a .dae, but although the camera is facing the right way, the tracking is completely off and very rough and jumpy, whereas it was perfect in Blender. Can anybody help me out here?


Where should I use interface as variable type? I see a lot of people say it's best practice to do so, but every example refers to collections:  List<String> list = new ArrayList<>()   Does this practice apply mostly to collections? I never saw anyone use interface when declaring i/o streams for example.

I have seen this mentioned a few times and I am not clear on what it means. When and why would you do this?   I know what interfaces do, but the fact I am not clear on this makes me think I am missing out on using them correctly.   Is it just so if you were to do:  IInterface classRef = new ObjectWhatever()   You could use any class that implements IInterface? When would you need to do that? The only thing I can think of is if you have a method and you are unsure of what object will be passed except for it implementing IInterface. I cannot think how often you would need to do that.   Also, how could you write a method that takes in an object that implements an interface? Is that possible?


What should be the criterion upon I should decide whether or not to buy a processor its speed? or the number of cores? meaning should I seek out a processor which is fast but has 2-3 cores or is it better to buy one with less speed but has a lot more cores?

With lowering silicon costs and rising consumer needs, manufacturers seem to be pushing one of two things: clock speed and/or core count.  With the way things are going, it doesn't seem that clock speed of processors is rising anymore, but the number of processor cores.  I remember only a few years back, I had a nice fast single-core Pentium 4 processor.  Fast-forward to today, and I don't think you can even purchase a single-core processor (not to mention the rising increase in multicore processors even in cellphones).  The way things are going, we might find computers with hundreds of cores in a few years (and I know many operating systems already have support for it).  Is it more beneficial to a system's overall performance to increase the clock speed, or increase the number of cores?  Assume we're getting into hundreds of cores all running together, or clock speeds ten times higher what we have today (regardless of whether or not that is physically possible).  What are some examples of common processes (e.g. encryption, file compression, image/video editing) that will most benefit from one or another?  Are there some processes which can be, but currently aren't (due to technical reasons) sped up by increasing their parallelism?    Assume the hypothetical processor has the exact same core design (word size, address bit width, memory bus size, cache, etc...), so the only variables here are clock speed and core count.  And again, I'm not talking about one, two, or even four cores - imagine tens to hundreds.


Is it possible when you know some n calculate the x if   $$n = x^x$$  ?  Sorry, I did't even know how this equation is called, any help appreciate.

How to solve following equation: $x^x = C$ as $x, C \in \mathbb{R}_{>0}$. I tried to use exponent and such that: $x\ln x = \ln C$.


If you go to Italy without a visa and leave at the 90 day mark, how long do you have to stay out of the country before you can return without a visa

I have searched the web a lot and could not find an answer that fits my situation. Here are two links that are quite contradictory:       My situation:  I've visited Portugal in December 2012 for 29 days on a Schengen visa valid from December 1st, 2012 to February 1st, 2013 for research purposes (I am a Ph.D. student). I want to visit Sweden from February 10th, 2013 to May 10th, 2013 (89 days). I have applied for a Schengen visa again (for research). How will the 90/180 rule work in my situation?


We know that some Wizards and Witches are familiar with the Muggle world, but are there some cases of people which start a life as a Muggle or "undercover wizard" in the Muggle community?

This Q/A (  ) made me realize that I can't seem to remember a single HP wizard/witch who had a Muggle job with a Muggle company, aside from Kingsley's bodyguard cover as the Prime Minister's secretary.  Everyone whom I recall being mentioned as having a job is either employed in some magical company or the Ministry of Magic (which seems to employ more magical people than every other employer combined) or be self-employed - again economically interacting with wizards.  Am I merely forgetting someone, or was Kingsley really the only magically capable person with a paycheck from the Muggle world (which doesn't count since the job was a cover)?  UPDATE: Just to clarify - I didn't necessarily mean "working a Muggle job while using magic to help you" - it could also mean simply doing a Muggle job. So there's not necessarily a concern about Statute of Secrecy (plus, you can use the magic, say, to learn - e.g. Hermione could magick herself to learn how to do dentistry in 1 month or something). So no need to answer how having some wizard doing a Muggle job would be contrary to HP universe rules. I merely want to know if there's an example, NOT why there should't be one.


Star Wars Episode III was titled as Revenge of the Sith. This title confuses me. We see Sidious and Vader getting rid of all Jedi which may be a part of revenge. However, what they are taking revenge for?

In Lucas canon (e.g. no EU/Legends, no new Disney content), what exactly did the Sith want revenge for?   What was the specific thing that they tried to avenge?


I am unable to get  to work with pdftex. Is there an alternative that will allow me to easily define a cube structure? I've looked at TikZ alternatives but they require me to define each sub cube in the structure, which is very time consuming.

I thought that PSTricks package was not possible to use in pdfLaTeX but .   How can I force pdfLaTeX to use PSTricks then?


let $a,b,c\ge 0$,and such $a+b+c=1$,show that $$\sqrt{1-ab}+\sqrt{1-bc}+\sqrt{1-ac}\ge2\sqrt{2}$$  maybe can use C-S to solve it.  My attempt is  $$\sum_\mathrm{cyc}\sqrt{a^2+b^2+c^2+ab+2bc+2ac}\ge 2\sqrt{2}$$ then I want to square, but it's ugly.

Let $x,y,z\ge 0$,and $x+y+z=2$, show that $$\sqrt{1-xy}+\sqrt{1-yz}+\sqrt{1-xz}\ge 2$$  Mt try: $$\Longleftrightarrow 3-(xy+yz+zx)+2\sum_\text{cyc}\sqrt{(1-xy)(1-yz)}\ge 4$$ or $$\sum_\text{cyc}\sqrt{(1-xy)(1-yz)}\ge\dfrac{1}{2}(1+xy+yz+zx)$$


I am aware that if I click on  in my chat profile I can see the most recent messages in the rooms where I have posted something lately. (And I can view the same information in profiles of other users.) Is there any place where I could see all my chat messages or, even better, all my messages in a given chat room?

I want to know my very earliest/first chat post in a chatroom. Is there perhaps a way to search/view all my posts and sort the results?


"If we find a prime $p$ such that $p\mid n$ , then $n/p$ is a positive integer that's smaller than $n$."   I understand $n/p$ is $n$ divided by $p$ but what is $n\mid p$?

What does this equation mean? What does the $|$ mean? $446617991732222310 | mn(m^k - n^k)$ Here is the complete question for reference -  What is the smallest positive integer $k$, such that for every ordered pair of integers $(m, n)$, we have $446617991732222310 | mn(m^k - n^k)$?  Please help


A square $10 X10$ is completed with numbers from 1 to 100 such that 2 consecutive numbers are in neighbor little squares.  Show that that on a line or a column there exists more than 2 perfect square.(A perfect square is a positive integer of the form $k^2$)  Looks that there are not too much ways to complete a such square.

Let   consider   a  square $10\times 10$   and  write  in  the   every   unit  square    the   numbers   from  $1$  to  $100$   such  that   every  two   consecutive  numbers  are  in   squares   which  has  a  common edge.  Then  there  are  two  perfect  squares   on  the  same line  or  column. Can  you   give  me  an  hint? How  to  start?


I'm using WordPress' built in gallery feature on a post. However, it produces the images with inline height and width attributes:

   And I have tried the following filters, but none work:  add_filter( 'get_image_tag', 'remove_width_and_height_attribute', 10 ); add_filter( 'post_gallery', 'remove_width_and_height_attribute', 10 ); add_filter( 'image_send_to_editor', 'remove_width_and_height_attribute', 10 );  function remove_width_and_height_attribute( $html ) {    return preg_replace( '/(height|width)="\d*"\s/', "", $html ); }   I am not sure what the image is defined as: a thumbnail, a gallery image? What do I need to filter to remove this?

WordPress automatically adds the width and height attributes to [gallery] shortcode images.  How to delete these attributes? Something  but for [gallery] output.


I have this fragment of code  final List<Account> result = this.jdbcTemplate.query(LIST_OF_ACCOUNT_SQL, new String[]{ids},  When I pass only one argument like         final String ids= "3213";  Code is working fine. But I have problem passing multiple arguments to my wildcard final String ids= "3213, 2313";  This is my SQL "SELECT ID, NAME FROM ACCOUNT WHERE STATUS = 'OK' AND ID IN (?) ";  I am using Oracle Database.

What are the best workarounds for using a SQL IN clause with instances of java.sql.PreparedStatement, which is not supported for multiple values due to SQL injection attack security issues: One ? placeholder represents one value, rather than a list of values.  Consider the following SQL statement:  SELECT my_column FROM my_table where search_column IN (?)   Using preparedStatement.setString( 1, "'A', 'B', 'C'" ); is essentially a non-working attempt at a workaround of the reasons for using ? in the first place.    What workarounds are available?


print(int( 342342342342342342 / 10 ))   The output is      34234234234234236   I do not understand where the 6 comes from! I also tried "long" which gives an error.

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


Does the protection Lily made on Harry apply only from Voldemort? Is there any proof from the books?

I know that when Lily sacrificed herself for Harry, Voldemort could no longer touch him and any attempted Avada Kedavra on Harry by Voldemort would rebound onto himself, until, of course, he took some of Harry's blood and put it into himself.   Now Harry and Voldemort share Lily's sacrifice and protection and also share Voldemort's soul since Harry is a Horcrux. When Voldemort tried to kill Harry in the Forbidden Forest, Harry was kept alive by his own blood which ran through Voldemort's veins. When Harry then challenged him a second time, Voldemort's killing curse rebounded onto him yet again since the Elder Wand won't kill its master.   But Voldemort shouldn't have been able to die since Lily's blood sacrifice lived in him and Harry should never be able to die either... shouldn't they both be immortal? I don't get it, someone help!


I have a table and inside this table every row is generated using ajax. In every row there is a select tag with an id(selectTax). I want to make a js function that occur when this select selected. For this i am using   $("#selectTax").change(function(){   console.log("vikash"); });   But when i am clicking on this nothing happening. Help me soon please.

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


I have a command block that teleports you to another place - it is permanently on (because of redstone), so whenever I get close to the command block, it teleports me - it is really annoying. How can I deactivate it?

I set a command block to /tp. It was supposed to activate only if you had 0 time left, and to activate the command block with a hopper clock to keep giving it power.   But it is not checking if you have 0 time left, so it keeps teleporting me. I can't get close enough to the command block to break it, so I'm stuck in a neverending teleport loop.  Any ideas?


E=-dv/dr.   But V=0 at equitorial line of a dipole and E  is not 0.Can anyone please help me how this is true?    Whenever function is 0,its derivative is always 0 i.e. if.  f(x)=0 then f'(x)=0 . Here f(x) is V which is 0,but f'(x) which is E is not 0. Please help.

For example, in a dipole, at the center of the two charges making up the dipole, the potential is zero but the electric field is non-zero. But if $E = -\operatorname{grad}V$, then why is $E$ not zero?  Another example: In the case of two positive charges, the electric field is zero at the mid-point of line joining them, but potential is non-zero. What am I misunderstanding here?


Is there a way to sync a specific device in Linux?  This would be used to ensure that, e.g., writes to a USB thumb drive have taken place without waiting for queued writes from a video processing job to complete on an unrelated RAID array.  If there is a system call / combination of parameters that can achieve this, I could probably write a simple C wrapper. If someone knows of a Ubuntu package that can do this, that'd be even better.

Is there a way to sync only one partition instead of all partitions?  Something like "sync /dev/sdc1".


If I have a device how give-me a latitude and longitude with 7 decimals (eg. -42.5124478, -22.3006726, longitude and latitude respectively ) and I round it to 4 decimals (eg. -42.5124, -22.3007).   It represents +-0.0001 of possible precision error.     The point is, imagining about a Earth a perfect sphere, I want to know what max limits from rounded decimals in Earth Surface according of rounding (based on this metric answered here   how much dislocation of surface area it will represents? and how to calculate it?

I have latitude and longitude as 19.0649070739746 and 73.1308670043945 respectively.   In this case both coordinates are 13 decimal places long, but sometimes I also get coordinates which are 6 decimal places long.   Do fewer decimal points affect accuracy, and what does every digit after the decimal place signify?


I told Serana to wait at whiterun at the front gate, I forgot about her and when I came back she wasn't there, where would she be?

I had parked my follower at an inn with a bunch of valuable items that I didn't want to carry. I guess I have been out a bit too long as this message appears:      Your follower tires of waiting and leaves.    There have been other situations where my follower has mysteriously disappeared as well.  How can I find my follower when they get up and leave or disappear into thin air?


I am trying to wrap my mind around special relativity and I have these questions:  If I am moving at 70% of the speed of light (relative to the ground) to the right, and my friend moves at 70% of the speed of light (relative to the ground) to the left, are we moving apart at faster than the speed of light?  Does this mean that from my perspective, he is moving away from me at faster than the speed of light?  How about from the perspective of a third party not moving (relative to the ground). Do they see us moving apart at faster than light?

Let's say we have $2$ particles facing each other and each traveling (almost) at speed of light.    Let's say I'm sitting on #$1$ particle so in my point of view #$2$ particle's speed is (almost) $c+c=2c$, double light speed? Please say why I am incorrect :)    EDIT: About sitting me is just example, so in point of view of #1 particle, the second one moves at (almost) $c+c=2c$ speed?


I have a question regarding referencing figures in the text. Say I have a figure in text with the caption Figure 1: Blah Blah. Then in my main text i refer to this figure saying something like "As you can see from Figure 1 etc...".   Then I realise I've forgotten to add a figure prior to this one and I insert a new figure earlier in the section which becomes figure 1, thus causing the old figure 1 to become figure 2. I'm assuming my in text reference earlier of "As you can see from figure 1 etc..." will not have changed to "As you can see from figure 2 etc...".  Am i right in assuming this?   Is there a way of working around this? I have a lot of figures in my document in a number of sections and at present my in text references just say "Figure XXXXXXXX" serving as a reminder to go fill them in at the end. However it would be good if I could do this sooner. Is there a way to ensure these change or do I just have to do it manually if I add figures in earlier sections of the text?   Hope the question is clear enough, please feel free to ask for more information if not. Thank you

Is it possible to automatically reference a figure and equations in text? I meant sth like bibliography references. Moreover, by changing the place of the figures or equations relevant figure or equation number can be changed automatically in text. Exp.:     In remote sensing Equation 1. is applied widely.      Equation 1.                     x= a+b


I need to do a logout button. I use Flask and Python and my website uses basic authentication so as to log in. I found out that the only possible way to log out is to close a browser (which is not what I'm looking for) or to change already entered login and password doing something like this:  user:pass@127.0.0.1:8000   It works when I input that phrase in URL but I'd like to do it programmatically.  My Python code:  @app.route('/logout') @auth.login_required def logout():     urlparameter = "user:pass@127.0.0.1:8000"     return Response(render_template('logout.html', urlparameter=urlparameter, mimetype='text/html'))   HTML button:  Logout   However, it doesn't work. How should I change it? Thanks

Is it possible to log out user from a web site if he is using basic authentication?  Killing session is not enough, since, once user is authenticated, each request contains login info, so user is automatically logged in next time he/she access the site using the same credentials.  The only solution so far is to close browser, but that's not acceptable from the usability standpoint.


Let $f,g:[0,1]\rightarrow [0,1]$ be measurable functions.Is $g\circ f$ measurable or not?  The composition is definitely measurable from the axiom definition of measurable function. But if we want to prove it from the classic definition of measurable function,we have to prove that preimage of an open set of this composition is measurable. In order to do that,we have to prove that the preimage of a mesurable set by a measurable function is a measurable set.Now I don't know what to do with the mesurable sets in $[0,1]$ except for the Borel sets.

We know that if $ f: E \to \mathbb{R} $ is a Lebesgue-measurable function and $ g: \mathbb{R} \to \mathbb{R} $ is a continuous function, then $ g \circ f $ is Lebesgue-measurable. Can one replace the continuous function $ g $ by a Lebesgue-measurable function without affecting the validity of the previous result?


Given $A$ is a $3$rd order Real Symmetric Matrix such that $A^6=I$ Then Prove that $A^2=I$  My try: Given that $A^6=I$ we have  $$A^6-I=(A^2-I)(A^4+A^2+I)=0$$  Now our aim to prove $A^4+A^2+I$ is an invertible matrix  Also $$A^4+A^2+I=(A^2-A+I)(A^2+A+I)$$  So to prove both $A^2-A+I$ and $A^2+A+I$  both are invertible  Can i have any clue?

Let$A$ be a $3\times3$ real symmetric matrix such $ A^6=I$ . Then $A^2=I$. How can I prove this statement is true or false? As it is given $A$ is symmetric so $A=A^T$. Also $ A^6=I$. But the main problem is that I can't operate $A^{-1}$ on both sides whether it is invertible or not. Can any help me what should I do?


I'm reading  to touch up on my Regex.  In the second chapter, Jan has a section on "special characters:"     Special Characters      Because we want to do more than simply search for literal pieces of text, we need to reserve certain characters for special use. In the regex flavors discussed in this tutorial, there are 12 characters with special meanings: the backslash \, the caret ^, the dollar sign $, the period or dot ., the vertical bar or pipe symbol |, the question mark ?, the asterisk or star *, the plus sign +, the opening parenthesis (, the closing parenthesis ), the opening square bracket [, and the opening curly brace {, These special characters are often called “metacharacters”. Most of them are errors when used alone.      (emphasis mine)   I understand that only open square bracket and open curly brace are special since a close brace or bracket is clearly a literal if there's no preceding open. However, why does Jan specify that close parenthesis is a special character if the other two close's aren't?

I am tired of always trying to guess, if I should escape special characters like '()[]{}|' etc. when using many implementations of regexps.  It is different with, for example, Python, sed, grep, awk, Perl, rename, Apache, find and so on. Is there any rule set which tells when I should, and when I should not, escape special characters? Does it depend on the regexp type, like PCRE, POSIX or extended regexps?


Checking the new backlinks to my website  in Google Search Console I noticed many backlinks in various junk blogs pointing to my website.  One example:   I am afraid such low quality backlings can spoil my backlink profile.  There are hundreds of such backlinks pointing to my website.  Who may be doing it? Shall I disawov all those crappy backlinks?  Can such backlinks result in certain pages of my website being hit by the Penguin algorithmic sanctions?

We have recently discovered a host of spammy links pointing to our website been put up in last 1 month through webmaster tool We have not engaged any seo agency/link building and have never created these links  Worst, these are spammy forum sites and almost some-one seems making an attack to our site as the link and keyword is same in all these sites Till not Have not received any warning, however as it has come to our notice - before any SERP getting down - we want to action this out  One thing we have observed is that - All these spammy links points to a single inner page of website  Pl suggest as have   a) Will Google disvow tool will work by stating to disvow these links  or  b) Is it a good way if we make this specific page 'nofollow' and even 'noindex' The reasoning behind this is like if the page is not followed and not indexed - the negative links pointing to the page of the site is already no follow and may be out from google serp  or what's the best alternate way to tackle this. Pl suggest in urgent help and advise required


This question is probably some variant of (or loosely related to) the pole-in-the-barn problem.   Simply stated, if I punch at relativistic speeds, would it experience Lorentz contractions so as to not reach the target? Or would it result in a paradox that the there is a hit from target's frame of reference but falling short from the puncher's frame of reference?  Below are the rules/notes -   Both the body and the target are stationary / at rest in relation to each other. Only the punching arm is moving.  The punch travels in a straight line towards the target.  The punch is being observed by both the target and the puncher.  We're not concerned about the mechanism and strength of muscles etc. The body can punch very close to the speed of light without breaking. It can be thought of as a spear thrust into a stationary target or  even a piston between two walls.  For simplicity, let's say that the length of the arm (or spear or piston) is same as the distance that the punch has to travel from the initial position to the target.    It might sound like an outlandish/comical problem but the core of the question is how it'll work from the reference frames of the target and the puncher.    EDIT 1: The punch stops after the arm has been fully extended but not because of it. In other words, let's say the length of the arm is 1m (and the distance to be traveled to make contact is also 1m), the punch knows to stop after traveling exactly 1m. The information/instruction that it has to stop after 1m is available to the punch (and every other part of the arm) before it is thrown. Deceleration happens instantaneously.

Yesterday we started relativity on our physics class, and my professor taught us a few concepts. We did some examples on how things changed by looking them from different reference systems, and a paradox came to my mind from an example he did on the blackboard:  Suppose that we have a bug inside a hole (and suppose that the height of the bug is $0$). This hole is $L$ meters deep. There's a man outside the hole that wants to kill the bug with a nail of length $l$, with $l<L$. Obviously, it's not possible for him to kill the bug by trying to push the nail in the hole. However, if the nail moves really fast, from it's reference system the hole will have a height $L_n<L$, and if it moves fast enough then it will happen that $L_n<l$, so he finally could kill the bug. On the other hand, the bug knows that from his reference system, the nail will have a lenght $l_b<l$, so it would never reach him.  Is it possible to quantify the problem? How is it possible that the nail reach the bug from it's reference system and from the bug's reference system it's even smaller than before?


In /etc/postfix/sasl/smtpd.conf I have:  auxprop_plugin: sql sql_engine: mysql sql_hostnames: 127.0.0.1 sql_database: mail sql_user: mailadmin sql_passwd: secret sql_select: SELECT password FROM users WHERE smtp_username = '%u' sql_usessl: no   This is working if I place a plain text password in the password field, but the database uses passwords stored with the MySQL ENCRYPT() function. Since the Query selects the password, rather than using the password in the where clause, how do I check that the user supplied password when ENCRYPT()ed matches the encrypted password in the database?  Is it possible to change the query to use ENCRYPT()ed passwords?

Is it possible to use MD5 password encryption to encrypt passwords when using Postfix / SASL and MySQL? Currently, my setup is using the MySQL CRYPT() function, which for various reasons isn't ideal.


Can someone give an example of a domain $G$ which has a boundary different from the boundary of its complement $G^c$?

$\newcommand{\bdy}{\operatorname{bdy}}$  I'm trying to show that $\bdy(A) = \bdy(A^c)$.  I know that $\bdy(A) = \operatorname{closure} A \setminus \operatorname{int}(A) = (\operatorname{int}(A^c))^c \setminus \operatorname{int}(A)$, but I don't know where to go from there.  Any help or hints would be very much appreciated.


Is it possible to take a part of mesh from an object in edit mode and copy paste it into another object's edit mode.  I am making a model and gloves are a separate object. I want to somehow make it and arms as single mesh what are the possible ways.

Hi im new to Blender and i want to know when im in edit mode if i can copy or cut a selections of polygons faces and paste to another mesh.  Thanks in advance for any help


The current handling of bounties when questions are migrated is somewhat inconsistent and incoherent. Active bounties are refunded to the asker prior to the question moving, which seems fine and good. Already awarded bounties are not handled as consistently, and bountiers complain about it on meta:  In , the points were simply disappeared, gone from both the offerer and the earner on both the source and destination site.  In , the bounty was initially deducted from the earner and refunded to the offerer, but then a mod stepped in to restore the bounty as previously offered and earned.   This is only going to come up more often as the SE network expands, especially as the new /review system facilitates migrating old flagged questions which would otherwise have just lingered. How should previously awarded bounties be handled during migration?

In March 2011 I offered a 500 bounty on one of my StackOverflow questions () and awarded it to Filip de Vos.   This question was later migrated to Database Administrators and has the following messages on it.     migrated to dba.stackexchange.com by Will♦ Dec 28 '11 at 12:25      This   question belongs on our site for database professionals who wish to   improve their database skills and learn from others in the community.   .     deleted Dec 31 '11 at 1:01   I appear to have been   on whereas Filip .  Is this a bug? Definitely doesn't seem fair or correct to me. The question still shows up in both our bounty tabs despite the migration. I would have hoped that the previously awarded bounty reputation points could still be honoured in this situation.


Can I substitute apple cider vinegar for white wine vinegar in a pasta and chicken dish?

I am about to use a recently viewed tv recipe for Rhubarb ketchup. Official ingredients include white wine vinegar but does say any vinegar 'will do'. I have some cider vinegar, will this dramatically alter the flavour or sweetness? Might I have to alter sugar quantity?


First thing I have to mention here, I'm new to python.  Now I have a file located in:  a/long/long/path/to/file.py   I want to copy to my home directory with a new folder created:  /home/myhome/new_folder   My expected result is:  /home/myhome/new_folder/a/long/long/path/to/file.py   Is there any existing library to do that? If no, how can I achieve that?

How do I copy a file in Python?  I couldn't find anything under .


When we write to any professor, we write Dear Professor X. If we write only Professor X, is it weird?   Professor X,    Best Regards,

When writing letter to an academic professor (not necessarily from student to professor), what is the appropriate way to address his/her title?  I have seen in letters using  Dear Prof. X even when the addressee is not a full professor  Dear Dr. X though, knowing that the addressee is a full professor  Dear Mr/Mrs X though, knowing that s/he has an academic title