I have Ubuntu 14.04 installed on an SSS running perfectly. Got a new 2TB drive that has Windows 7 installed on it.  How do I add Windows 7 to my grub menu?  This is output of sudo update-grub:   Searching for GRUB installation directory ...  found: /boot/grub Searching for default file ...  found: /boot/grub/default Testing for an existing GRUB menu.lst file ...  found: /boot/grub/menu.lst Searching for splash image ...  none found, skipping ...  Found kernel: /boot/vmlinuz-3.13.0-51-generic  Found kernel: /boot/vmlinuz-3.13.0-49-generic Found kernel: /boot/vmlinuz-3.13.0-24-generic  Found kernel: /boot/memtest86+.bin Updating /boot/grub/menu.lst ... done   This is the output of sudo os-prober:   sudo os-prober /dev/sdc1:Windows 7 (loader):Windows:chain

I have finally installed Ubuntu on my second drive. When I start my computer GRUB only offers me to boot Ubuntu, not Windows 7. What needs to be done so that I can choose between Ubuntu and Windows in GRUB?  When I press F12 for boot menu at startup and I choose Windows Boot Manager it boots into Windows 7.    I ran command sudo fdisk -l and here is log ():  WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.   Disk /dev/sda: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0xc3ffc3ff     Device Boot      Start         End      Blocks   Id  System /dev/sda1               1  1953525167   976762583+  ee  GPT Partition 1 does not start on physical sector boundary.


I'm planning to add a set of recessed lights to an existing circuit in my home.  The existing circuit is fairly simple: one light, controlled by one switch, and there is no insulation in the wall or ceiling.  My dilemma is in adding the fixtures into the circuit between the existing fixture and the switch.  I will need to splice additional wire into the circuit, but I'm certain there isn't enough slack to draw the existing line into the fixture's junction box to make the connections.  Should I run new line from the existing fixture to ensure that the connections happen inside the box?  Otherwise, can I splice a short segment into the existing line to get the slack I need?

Is there a way without using junction boxes to simply splice in additional length of 12/2 NM-B cable? Can I use twist caps?  I'm putting in a dog door and as it so happens, there is some 12/2 right in the way of the location I've chosen. There's no additional slack in the cable, and I don't want to rip up more drywall than I have to. I'm tempted to just cut it and splice in an additional foot or two with twist caps to get it out of the way. I don't know if this is safe or legal. Do I need to get junction boxes? Attached some pictures for fun.  Also, there is a 1-gang electrical outlet box that is going to the outside. I'm moving that up a bit.


I am willing to know the appropriate resolution for making panaflex print of about 5ft by 6ft or higher as billboard print.

(This question is meant to be a resource to direct others to given that this is a common question.)  Given the task of creating an image that will be printed at a certain size, what pixel dimensions and resolution should I be setting my file at?


I'm going to permit redirections ">>" and ">" for the www-data user in sudoers but I can't find this.

I am trying to follow what I assume is best practices of using sudo instead of root account.    I am running a simple concat file operation such as:  sudo echo 'clock_hctosys="YES"' >> /etc/conf.d/hwclock   This fails as to the right of the ">>" it is running as the normal user.  Adding extra sudos also fails (expected behaviour since piping to the sudo command and not to the file).  Example is just that but it has been verified and tested under the root account.


Question: Disprove that for all integers $a,b$ that if $d=gcd(a,b)$ then $d=gcd(a^2,b)$ or $d=gcd(a,b^2)$ Attempts. I thought to first try $a=b$, then $d=a$ and $gcd(a^2,b)=b=d$ Ok, how about $a=0, b \neq 0$, then $d=b$ and $gcd(a^2,b)=b=d$ Ok, if $a,b$ are co-prime, then the $d=1$ and $gcd(a^2,b)=1$ Ok, maybe $a=b^2$, then $d=b$ and $gcd(a^2,b)=b$ Not sure what else to try. Maybe the problem is wrong? I copied it down carefully. Hints appreciated.

Let $p$ be a prime. Suppose that $\gcd(a, b) = p$. Find $\gcd(a^2,b)$  for all integers a and b.   I was able to prove that $\gcd(a^2,b^2) = p$ but I don't know if it helps.  Any help is greatly appreciated.


So basically, I'm trying to create a simple java calculator for the following functions but it seems my functions are not executing the way they're supposed (i.e. + not adding, - not subtracting). Would appreciate some help :)      if (ope == "+") {         //add     } else if (ope == "-") {         //subtract     } else if (ope == "*") {         //multiply     } else if (ope == "/") {         //divide     } }

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?


I'm working on a 2D-ish animation (camera above looking straight down to flat objects) for an educational video and am wondering how to create two effects. The first one I'd need is the appearance of something being put on like a sticker. Where it starts out curved or rolled away from the camera and then it lays out flat.

I want to animate a paper as it's being tightly rolled. I've done some research and seen that using the spiral add on might be advantageous, but I haven't found anything relating specifically to my question.   How might I do this?


I am trying to find a line in haproxy configuration file:  global         log 127.0.0.1   local0         log 127.0.0.1   local1 notice         #log loghost    local0 info         maxconn 32768         tune.maxaccept -1         chroot /var/lib/haproxy         daemon         stats socket /var/run/haproxy.sock mode 600 level admin         stats timeout 2m         timeout http-request 5000  defaults         log     global         mode    http         option  httplog         option  dontlognull         retries 5         option redispatch         maxconn 16384         timeout connect 7s         timeout client  500s         timeout server  500s         timeout http-request 7000         timeout client-fin      30s         timeout tunnel  1h   What is the regex to match the line timeout http-request 5000 but only in global section. Also, we need to ensure to exclude #.

I don't really understand regular expressions.  Can you explain them to me in an easy-to-follow manner?  If there are any online tools or books, could you also link to them?


Would like to append path variables to end of line on a specific row with search pattern and append, "Defaults    secure_path" string I want to append: :/etc/bla/foo/  the file,      filename   # asdf # lkaj # asdah  Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin  ## safdafdhdahdabfdabf ## Aedhadhfdahdahadhda   Tried pattern search for "Defaults    secure_path" and append to end of line:  sed '/^Defaults    secure_path = / s/$/ :/etc/bla/foo/' filename   But, got error:   sed -e expression #1, char 38: unknown option to `s'

I have a directory full of XML files that look like this, for which I want to change the value of the "offset" element number from 1 to some other number  $ cat my.xml       <offset xmlns="">1</offset>   I wrote various combinations of this sed command, but nothing I tried runs without an error.  I am pretty sure that I need to escape some of the characters, but those that I've tried always end in errors ("unexpected token", "unknown option", etc).  I also tried without the -e flag, since it really isn't an expression.  sed -i -e s/<offset xmlns="">1</offset>/<offset xmlns="">99</offset>/ *.xml   Any help would be appreciated.


Is there a biblatex command that prints a bibliography entry? A command that prints this entry for example: Prunescu and Sin 2013 - Bioresource Technology Vol. 150C, p. 393-403 which is defined in my .bib file.  I need it on a slide in beamer.

When we do   \bibliographystyle{style} \bibliography{References.bib}   We get all the references at the end of the document, with some kind of reference/id in the document.   What I need is the complete reference in the document itself (not at the end) and then to be able to write what I want below this reference. For example;  Chaminade, T., Hodgins, J., & Kawato, M. (2007). "Anthropomorphism influences perception of computer-animated characters' actions." Social Cognitive and Affective Neuroscience 2(3): 206-216      - Some text..........      - Some more text.......  Cowley, S. J., Kanda, T. (2005). "Friendly machines: interaction-oriented robots today and tomorrow." Alternation 12(1a): 79-106.      - Some text.....      - Some more text....   How can I do it? Thanks.


I have three huge tables each with many many columns (say 500 each). Each of these tables joins together to form that data that I need by the 'USER_ID' field.   What is the easiest way to select this without duplicating the "USER_ID" field 3x?  I don't want to have to type out 'select table1.col1.....table3.col500'   my current query:  select table1.*, table2.*, table3.* FROM table1 JOIN table2 on table1.user_id  = table2.user_id JOIN table3 on table1.user_id =  table3.user_id   I'd like to do some sort of 'except table2.user_id, table3.user_id' in the select portion of the statement so I don't see this column there 3x...

I'm trying to use a select statement to get all of the columns from a certain MySQL table except one. Is there a simple way to do this?  EDIT: There are 53 columns in this table (NOT MY DESIGN)


I've just bought a new Toshiba laptop, on which Windows 8 is preinstalled. I've installed Ubuntu Gnome 13.10 and GRUB2 correctly detects Ubuntu and Windows. But the strange problem is that when I try to boot Windows 8, it appears the following error:  /EndEntire file path:/ACPI(a0341d0,0)/PCI(2,1f)/UnknwnMessaging(12)/HD(2,200800,82000,a8d996409dcfe211,a8,59)/File(\EFI|Microsoft\Boot)/File(bootmgfw.efi)/EndEntire error: cannot load image.   I've tried to solve using boot-repair, using the auto-correction. But never has changed. Here is the log generated by boot-repair:   How can I fix this?

I've just purchased a new Acer Aspire V3-771G laptop which came pre-installed with windows 8.  I shrunk the main windows partition and installed Ubuntu 12.10. I then had to run boot-repair to be able to boot to Ubuntu. .  This worked and I could now boot Ubuntu and it provided me with 3 other entries which should supposedly allow me to boot back to windows 8. However when trying these menu entries I get the following errors:  Windows UEFI bkpbootmgfw.efi  /EndEntire file path: /ACPI(a0341d0,0)/PCI(2,1f)/UnknownMessaging(12) /HD(2,c8800,96000,fe030bf1430a6047,9a,9a)/File(\EFI\Microsoft\Boot) /File(bkpbootmgfw.efi)/EndEntire error: cannot load image.   Windows Boot UEFI loader  /EndEntire file path: /ACPI(a0341d0,0)/PCI(2,1f)/UnknownMessaging(12) /HD(2,c8800,96000,fe030bf1430a6046,9a,9a)/File(\EFI\Boot) /File(bkpbootx64.efi)/EndEntire error: cannot load image.   EFI/OEM/Boot/bootmgfw.efi  /EndEntire file path: /ACPI(a0341d0,0)/PCI(2,1f)/UnknownMessaging(12) /HD(2,c8800,96000,fe030bf1430a6046,9a,9a)/File(\EFI\OEM\Boot) /File(bootmgfw.efi)/EndEntire error: cannot load image.   I have looked in the /boot/efi partition and the .efi files listed in grub are there but I always get this error.


I'm using the latest arch kernel 5.7.12-arch1-1, the latest bash version 5.0.017-1 and the latest coreutils-8.32-1 which the find utility is a part of. I have the following code in my .bashrc to make easy work of finding files on the system. But I can't quite get it working. At the bash command prompt the following all produce the correct output, listing the correct files I wish to locate find . -iname '*driving*licence*part*' find . -iname '*driving*licence' find . -iname '*driving*' So why does f driving licence part f driving licence f driving using the below function not? Each if statement is parsing for the number of variables provided. function f () {            # find files            # update the files location database       sudo updatedb       if [ -n "$1" ] && [ -n "$2" ] && [ -n "$3" ]; then        find . -iname '*$1*$2*$3*'     fi      if [ -n "$1" ] && [ -n "$2" ]; then        find . -iname '*$1*$2*'     fi      if [ -n "$1" ]; then        find . -iname '*$1*'     fi   }

I am seeing different results from the find command between being run manually on the command line vs run in a script.   If I run the following on the command line:   find . -name '*.txt' ! -name '*20120427.txt'    I get all the .txt files in a directory except for the ones with the date that I want to avoid.  But when I have this same line in a script with a variable to identify the date:  FDATE=`date +%Y%m%d` find . -name '*.txt' ! -name '*${FDATE}.txt'    The script finds all the .txt files including the ones with the date I want to avoid.   The only difference between the 2 is that I am passing the FDATE variable in the script. Is there something obvious I am missing? I do not understand why the results are coming out different.


I would like install Xposed framework. My device is running Android L (5.0.2). The Xposed framework is compatible with android 5?

I want to install the xposed framework on my Nexus 5 and in the framework, the install/update option doesn't work.  My Nexus 5 runs Android 5.0 (Lollipop).


We can use goto and :label in batch. Is there anything like it in Python?

Is there a goto or any equivalent in Python to be able to jump to a specific line of code?


I've tried everything I can think of but longtable just won't allow me to  add a caption and label to the top of the table.   My table looks like this:    But when I add in a caption and figure, overleaf/texstudio both crashes. Here's my code:  \documentclass[10pt,a4paper]{article} \usepackage[hmargin=1cm, top=2cm]{geometry} \usepackage{amsmath, amssymb} \usepackage{hyperref} \usepackage{graphicx} \usepackage{booktabs, makecell, longtable} \newcolumntype{L}[1]{>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}p{#1}} \parindent=0em \parskip=20pt  \usepackage{enumitem}   \begin{document} \begin{center}  \setlist[itemize]{topsep = 1ex, parsep =0pt, leftmargin=*,after=\vspace{-\baselineskip}} \begin{longtable}{ll L{5.5cm} L{4.5cm}}     \caption{Table of 2013 Census variables used in this dissertation}      \label{Table 2.1}     \toprule     \textbf{Variable} & \textbf{Census Code} & \textbf{Description} & \textbf{Study Variables} \\  \midrule     Education & cen\_ind\_std\_highest\_qual\_code     & This variable records the highest qualification achieved by an individual. A qualification is a formally recognised award for educational or training attainment by one of the following authorities: \begin{itemize}     \item New Zealand Qualifications Authority and their recognised approval bodies     \item Universities New Zealand     \item Associations of Polytechnics of New Zealand     \item Association of Colleges of Education in New Zealand     \item Recognised overseas authorities \end{itemize}         & \textbf{highest\_qual}             \begin{itemize}[leftmargin=1.5em]         \item[0.]   No formal qualifications         \item[1.]   Level 1, 2, or 3 certificate         \item[2.]   Level 4, 5, or 6 certificate         \item[3.]   Undergraduate degree         \item[4.]   Postgraduate degree         \item[9.]   Missing or unidentifiable             \end{itemize}   \\ \bottomrule \end{longtable} \end{center} \end{document}

I want to have a longtable like this:  \begin{center} \begin{longtable}{|p{2cm}|p{3cm}|p{7cm}|p{3cm}|} \caption{my caption} \hline 1 & 2 & 3 & 4\\  \hline  \hline 1 & 2 & 3 & 4\\ \hline 1 & 2 & 3 & 4\\ \hline . . . 1 & 2 & 3 & 4\\ \hline  \label{variability_impl_mech} \end{longtable} \end{center}   but when I try to compile this, I get this error: !Misplaced \noalign  when I write the caption after the last \hline, it works fine. I want to have the caption on top of my table but this error appears.


What is the fastest speed (in miles per hour) that a massive object can travel at? I have heard that an object can travel at the speed of light, but I've also heard that massive objects cannot travel at the speed of light.

I'm in a freshmen level physics class now, so I don't know much, but something I heard today intrigued me. My TA was talking about how at the research facility he worked at, they were able to accelerate some certain particle to "99.99% the speed of light". I said why not 100%, and I didn't quite understand his explanation, but he said it wasn't possible. This confused me. Since the speed of light is a finite number, why can we go so close to its speed but not quite?  Edit: I read all the answers, and I think I'm sort of understanding it. Another silly question though: If we are getting this particle to 99.99% the speed of light by giving it some sort of finite acceleration, and increasing it more and more, why cant we increase it just a little more? Sorry I know this is a silly question. I totally accept the fact we cant reach 100%, but I'm just trying to break it down. If we've gotten so close by giving it larger and larger acceleration every time, why cant we just supply it with more acceleration? And how much of a difference is there between 99.99% the speed of light, and the speed of light? (I'm not really sure if "difference" is a good word to use, but hopefully you get what I'm asking).


I was solving practice problems for my upcoming midterm and however I got stuck with this question type.  It is asking me to find all roots and then sketch it.  $(1+i\sqrt{3})^{1/2}$  How do we proceed?

If I'm given a complex number (say $9 + 4i$), how do I calculate its square root?


if we look at $S_3$ so we have $|G|=6=3*2$  Now to find the number of Sylows subgroup we look at all the divisors of $6$ which are: $1,2,3,6$  $n_2:$ will be all the number that $2$ does not divide so it is $1,3$  $n_3:$ will be all the number that $3$ does not divide so it is $1,2$  Is that correct?

Find the three 2-Sylow subgroups of $S_3$ and find a 2-Sylow subgroup and a 3-Sylow subgroup of $S_4.$  I just learned Sylow' theorem at the moment and I don't know how to do these problems. I know a p-Sylow subgroup of a group $G$ is a subgroup of order $p^k$, where $p^k$ divides the order of $G$ but $p^{k+1}$ does not. $|S_3| = 6 = 2\dot\ 3$ and $|S_4| = 24 = 2^3\dot\ 3$. How can I solve these types of problems?


What do i have to do to join highlighted group of faces with others, so shadow will be the same when joined. All faces are already part of same object (Joined them via Ctrl + J). I tried merging them and bridging them but without correct effect. Also i selected both edges and filled missing spaces (F), but shadow didn't correct. Both groups are completly together.

While rendering a mesh with smooth shading on, I get a dark region/shadow on certain faces. The effect is more evident when smooth shading is applied to a mesh containing ngons, with the ngons turning black when rendered.   The blackening effect is visible in the viewport too.  How can I solve this problem?


I am having a very hard time understanding the , from an intuitive level. I've had a lot of people trying to explain this to me, including my professor and my brother, who is a graduate statistics student. However, I can only understand up to the part that the host's door choice is not random, but cannot wrap my head around the fact that this non-randomness makes the probability to win, if the player switches doors, jumps from 1/3 to 2/3. Note: I am a maths graduate student who doesn't have much experience with everyday life's statistics situations. Learning statistics/probability to me has always been challenging, not because of the maths, but because of the (intuitive) meaning of the equations. This Monty Hall problem is an example of my inability to comprehend a real-life statistics situation. While answering the question, please keep in mind that I hope to relate this Monty Hall problem to something intuitive that I can experience in real life.

From Wikipedia :     Suppose you're on a game show, and   you're given the choice of three   doors: Behind one door is a car;   behind the others, goats. You pick a   door, say No. 1, and the host, who   knows what's behind the doors, opens   another door, say No. 3, which has a   goat. He then says to you, "Do you   want to pick door No. 2?" Is it to   your advantage to switch your choice?   The answer is, of course, yes - but it's incredibly un-inituitive. What misunderstanding do most people have about probability that leads to us scratching our heads -- or better put; what general rule can we take away from this puzzle to better train our intuition in the future?


Can you change the wavelength of light keeping frequency constant and can you do the opposite as well? I understood the basics but please don't hesitate to go deeper into the concept. Also, If you happened to have an elegant explanation please drop it here if you can.

When light waves enter a medium of higher refractive index than the previous, why is it that:  Its wavelength decreases? The frequency of it has to stay the same?


sda6 is ext4 file system and where my ubuntu is installed, 30GB. sda3 is "ntfs" file system and where my windows is installed, 400GB. sda7 is a 50 GB empty partition with "ext4" file system.   How to move the space of sda7 to sda6 to let sda6 become 50+28=78 GB.    Here's a real case of mine :( I want to add more space into my ubuntu (28.2 GB one) from other emtpy partition space.

Previously, I have installed Windows 7 on my 320 GB laptop with three partitions 173, 84 and 63 GB each. The 63 GB partition was where the Windows was installed. The rest were for file containers.  Now I changed my OS to Ubuntu 12.04 LTS. I installed Ubuntu by replacing the entire Windows 7 on the 63 GB partition. The rest of the partitions remain as an NTFS Windows partition and I can still access them both (the 173 and 84 GB partitions).  Now I want to change the two partitions of Windows into an Ubuntu format partitions plus most importantly, I want to extend the 63 GB partition to more than a 100 GB because at the moment I am running out of disk space. Whenever I try to install any application, especially using wine, it always complains for a shortage of disk space.  How do I do the extending activity before I entirely format my laptop again and lose all the important files on my partitions?


I have the Windows version of Steam installed on my laptop...since it's a laptop I'll be wanting some of that space back, but I don't know how to uninstall a .exe file. I have the latest WINE-Staging installed and I'm running the latest Ubuntu 18.10.

I am using Ubuntu 11.10. By using wine software i installed some software like nimbuzz and ibibo messenger. Both the programs are not working and showing the bug as We're sorry, but an unknown error has caused ibibo Messenger to close.  So I wanna uninstall those.   How to uninstall those type of programs which I installed through Wine?


Recently a question of mine got an unusual surge in upvotes, I guess I may have been linked from some high visibility blog or something like that.  Is there any way to know the traffic sources for a question?

There are a number of questions on Programmers' that seem to be getting a lot of traffic:      for example.  I'm curious as to why these questions are getting lots of views, while others aren't. So I'd like to know if anyone has posted a link on Twitter, Facebook, Reddit etc.  Can the referrer urls for individual question be made available to the moderators?  I'm not asking for exact and/or precise information - just the domain would do.  Obviously we'd need the a "most viewed" page in the moderator tools somewhere which would show these questions with a popup or link that showed the referrers for this link. A threshold of some kind for the number of views would probably be required to limit the queries made.  (NOTE: I'm not discussing the quality of said questions).


Would it be more correct to say that a photon, traveling at the speed of light, would experience all points in time simultaneously, and therefore be everywhere at once?  It might be just our perception that seems to portray them as moving?

To an an external observer it appears that time has stopped for photon. But this relation is reflexive, so for an observer travelling with the photon it appears the universe has stopped everywhere.  Is this right?  Space also gets distorted parallel to the direction of motion, but not perpendicular to it.   Does this mean that for an observer travelling with a photon sees spacetime as a flat plane?  Note 1: I'm using language vividly not literally when I say a photon experiences space and time. Not that I'm against idealist or panpyschist interpretations of matter or energy come to that.  Note 2: Since it's been pointed out that an inertial frame can't be boosted into the frame of a photon and moreover there is no limiting behaviour here - no matter what frame you are boosted into, light will always appear to travel at c. Nevertheless, when an external observer watches a train chasing a photon by gradually increasing its speed, he will note that the train speed is approaching the speed of the photon (but will never match it) and when he looks at the clock inside the train he will not too that it is gradually slowing down (but never actually stops). Using this picture, we can attempt the thought experiment - if not one that can be carried out - of what a world looks like to a photon.


For some reason I am getting an unresolved reference 'i' error here in python 3.9.x How can I amend my code to get it to run without error?  for card in range(len(cards)):     card = cards[i]     print(f"{i+1} - {card}")  # get choice choice = get_int_input(1, len(cards)) # get card return cards[choice-1] if choice else None  '''

I could swear I've seen the function (or method) that takes a list, like this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:  for i in range(len(name_of_list)):     name_of_list[i] = something   but I can't remember the name and googling "iterate list" gets nothing.


my power supply died last night rather spectacularly: blue sparks, popping sounds, a smell of burning plastic. the computer shut down, then tried to start itself up again, and sparked and popped some more before I was able to turn off the power switch on the back (in retrospect: was that dangerous of me? just reaching toward it to hit its switch?) and unplug it.  so clearly THAT needs to be replaced. but I have to wonder: what are the chances that OTHER components were damaged as well? can I simply buy a new power supply, and expect things to work? or could doing so actually be dangerous? could another component - like the motherboard, graphics card, or hard drives - have been damaged in such a way that plugging in another power supply would simply kill THAT power supply? (or damage other components that somehow survived the first assault?)  I've been building desktops casually, for myself, for a little over 10 years now, but I would by no means consider myself an expert in computer hardware or electronics, and something like this has never happened before. I'm a bit out of my depth.  other details, in case they may be of help:   the power supply is a Cooler Master RS-460-PSAR-I3. I bought it about 3 years ago, when I built this computer. (no internal components were reused, except two SATA drives.) I don't overclock anything; I never have. one of the two case's side fans died a few months ago. these fans are an unusual size (250mm), so had trouble finding a replacement, and then never got around to replacing it. I can't deny the possibility that things have been running hot for a while. (I was worried about this when the fan first broke, so kept an eye on a CPU temp program for a couple days afterwards. I don't remember the numbers, but I remember being unconcerned, though I am aware that these programs are unreliable by their nature.)   thanks for any help!

A couple days ago I booted up Left 4 Dead, but then heard a pop and my computer turned off. It smelled like dead electronics so I unplugged the computer. I figured it was a power supply failure, so I ordered a new Corsair HX520 and tried to install it today, hoping that was the only thing that needed replacing.  However my computer most emphatically did not work. Case fans turned on, a few motherboard lights and optical drive power lights turned on, but neither my GPU fan or my CPU fan turned on. Also one of my hard drives sprayed a few sparks from its underside and a bit of smoke came from it. I figure that one is dead. There was also no signal to the monitor or beep codes. I quickly turned the computer off to avoid any potential CPU overheating and tried with only 1 stick of RAM and no hard drives and got the same result.  What does this mean? Does the GPU fan not turning on mean the video card is shot? What does the CPU fan not turning on mean? Is the motherboard dead as well, or the CPU, or both? Should I just spring for a new computer at this point?  (edit) Also, can a power supply failure hurt your RAM?


I am using the following expression for URL validation.   ^(https?:\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$   However, when I have   "httpcolonforwardslashessite" (colon = : and foward slashes = //)   it still passes it as a url. how can I modify the above expression to make sure that there is ".com/net" at the end?  Thank you  tldr: I want to check for .com or .net at the end of url. What changes can I make to above exp to achieve this?

How can I check if a given string is a valid URL address?  My knowledge of regular expressions is basic and doesn't allow me to choose from the hundreds of regular expressions I've already seen on the web.


This is the series in question:  $$S = \frac{1}{1+1^2+1^4}+\frac{2}{1+2^2+2^4}+\frac{3}{1+3^2+3^4} \ldots$$  The general term seems to be:  $$T_n=\frac{n}{1+n^2+n^4}$$  In the original question, which is from Resonance DLPD Algebra, the value of $14S$ is asked.  I haven't been able to make any progress on this question even after trying for a long time. I don't know how to handle series where the denominator contains sum of numbers in general. Can you please provide a hint?

Problem :   How to find the sum of the sequence $\frac{1}{1+1^2+1^4} +\frac{2}{1+2^2+2^4} +\frac{3}{1+3^2+3^4}+.....$  I am unable to find out how to proceed in this problem.. this is a problem of arithmetic progression... Please suggest how to proceed...Thanks..


I am trying to run the bubble picker code(android) in github which is already available,but still getting these exceptions.Tried multiple suggestions but still getting same things,Please help me in resolving these exceptions. Tried these things:Invalidate & Restart,Changing properties file,Clean and rebuild  XML Code:  <com.igalata.bubblepicker.rendering.BubblePicker     android:id="@+id/picker"     android:layout_width="match_parent"     android:layout_height="match_parent"     app:backgroundColor="@android:color/white" />   Java Code:  public class Screen1Animation extends AppCompatActivity {  BubblePicker picker; protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.screen1animation);     //picker = (BubblePicker)findViewById(R.id.picker);     final String[] titles = getResources().getStringArray(R.array.titles);     final TypedArray colors = getResources().obtainTypedArray(R.array.colors);     final TypedArray images = getResources().obtainTypedArray(R.array.images);      try {         picker.setAdapter(new BubblePickerAdapter() {              @Override             public int getTotalCount() {                 return titles.length;             }              @NotNull             @Override             public PickerItem getItem(int position) {                 PickerItem item = new PickerItem();                item.setTitle(titles[position]);                 item.setGradient(new BubbleGradient(colors.getColor((position * 2) % 8, 0),                         colors.getColor((position * 2) % 8 + 1, 0), BubbleGradient.HORIZONTAL));                 //item.setTypeface(mediumTypeface);                 item.setTextColor(ContextCompat.getColor(Screen1Animation.this, android.R.color.white));                 item.setBackgroundImage(ContextCompat.getDrawable(Screen1Animation.this, images.getResourceId(position, 0)));                 return item;             }         });   Exceptions:  FATAL EXCEPTION: main Process: com.example.sampleapp, PID: 24972 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.sampleapp/com.example.sampleapp.Screen1Animation}: android.content.res.Resources$NotFoundException: Resource ID #0x0     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3194)     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3302)     at android.app.ActivityThread.-wrap12(Unknown Source:0)     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1891)     at android.os.Handler.dispatchMessage(Handler.java:108)     at android.os.Looper.loop(Looper.java:166)     at android.app.ActivityThread.main(ActivityThread.java:7425)     at java.lang.reflect.Method.invoke(Native Method)     at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:245)     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:921)  Caused by: android.content.res.Resources$NotFoundException: Resource ID #0x0     at android.content.res.ResourcesImpl.getValueForDensity(ResourcesImpl.java:288)     at android.content.res.Resources.getDrawableForDensity(Resources.java:1026)     at android.content.res.Resources.getDrawable(Resources.java:969)     at android.content.Context.getDrawable(Context.java:609)     at android.support.v4.content.ContextCompat.getDrawable(ContextCompat.java:463)     at com.example.sampleapp.Screen1Animation$1.getItem(Screen1Animation.java:45)     at com.igalata.bubblepicker.rendering.BubblePicker.setAdapter(BubblePicker.kt:37)     at com.example.sampleapp.Screen1Animation.onCreate(Screen1Animation.java:29)     at android.app.Activity.performCreate(Activity.java:7383)     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1218)     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3147)

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?


i have to use the IEEE Latex  for the Conference Paper. I downloaded it and the Authors do not line up correctly. The names are displayed to each other. \documentclass[conference]{IEEEtran} \IEEEoverridecommandlockouts \usepackage{cite} \usepackage{amsmath,amssymb,amsfonts} \usepackage{algorithmic} \usepackage{graphicx} \usepackage{textcomp} \usepackage{xcolor} \def\BibTeX{{\rm B\kern-.05em{\sc i\kern-.025em b}\kern-.08em T\kern-.1667em\lower.7ex\hbox{E}\kern-.125emX}} \begin{document}  \title{Paper Title*\\ {\footnotesize \textsuperscript{*}Note: Sub-titles are not captured in Xplore and should not be used} \thanks{Identify applicable funding agency here. If none, delete this.} }  \author{\IEEEauthorblockN{1\textsuperscript{st} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{2\textsuperscript{nd} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{3\textsuperscript{rd} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{4\textsuperscript{th} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{5\textsuperscript{th} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{6\textsuperscript{th} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} }  \maketitle  \begin{IEEEkeywords} component, formatting, style, styling, insert \end{IEEEkeywords}  \section{Introduction} \end{document}   Any Ideas how to fix this Problem ? (Because this simply looks stupid.)

How do I align author names such that the first three authors appear in 3 column format and the last two in two column?  \author{\IEEEauthorblockN{1\textsuperscript{st} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{2\textsuperscript{nd} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{3\textsuperscript{rd} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{4\textsuperscript{th} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} \and \IEEEauthorblockN{5\textsuperscript{th} Given Name Surname} \IEEEauthorblockA{\textit{dept. name of organization (of Aff.)} \\ \textit{name of organization (of Aff.)}\\ City, Country \\ email address} }


Go to SO Careers 'Support' page:  Then, click on the '' link under the 'More Information' section. The link currently points to:     Upon doing Google search I found:  I believe this is a correct link.

As SE developer Chris explains in :     We use a Jekyll-based blog generation system. Unfortunately, sometimes some of the pages do not generate correctly, thus causing the files to be missing. Regenerating the blog usually solves this, but knowing when we have a "busted blog build" is half the battle. (The other half of the battle is fixing the system for good so that all pages generate correctly all the time.)    This happens quite often, think the first time was reported as .  All past reports are about single missing page, hence starting now a "generic" report.  I am aware the battle is long and hard, would be happy to get updates about the progress right here in this report. :)


For a unit test of C dode, I want to ascertain that a value passed as a void * is, indeed, a valid pointer.  I don't think that I can prove that it definitely is a valid pointer, but how can I say that it probably is? Or definitely is not?  I am developing and unit testing on a 64 bit Intel processor, and the target is an ARM 9. I am not averse to assembler inserts.   is there a minimum value for a valid pointer? 0x08 doesn't look very pointer-ish, wheras values above 0x1000000 do. must it be divisible by something (say 8)? can I say with 100% certainty that an odd number is not a valid pointer?   I don't need a flawless answer, just something to catch most errors.    [Update] I am considering looking at the link map, although that seems like overkill. The problem is occuring when casting to remove compiler wanrings.  Some system calls require a char * or void *, and csting to those is masking some coding errors.

Is there any way to determine (programatically, of course) if a given pointer is "valid"? Checking for NULL is easy, but what about things like 0x00001234? When trying to dereference this kind of pointer an exception/crash occurs.  A cross-platform method is preferred, but platform-specific (for Windows and Linux) is also ok.  Update for clarification: The problem is not with stale/freed/uninitialized pointers; instead, I'm implementing an API that takes pointers from the caller (like a pointer to a string, a file handle, etc.). The caller can send (in purpose or by mistake) an invalid value as the pointer. How do I prevent a crash?


Why is $e$ the number that it is?  Most of the irrational number that we learn about in school have something to do with geometry, like $\pi$ is the ratio of a circle's diameter to its circumference.  Those numbers can also be derived using maths ($\pi = \lim_{n\to\infty}4\sum_{k = 1}^{n}\frac{(-1)^{k+1}}{2k - 1}$).  On the other hand, $e$ is derived only from math, and finds no other immediate geometric basis.  Why then, is $e$ the number that it is ($2.7182\ldots$) and not some other number?  EDIT: My question is more along the lines of why $e$ is $2.7182\ldots$ On an alien world where there is a different system of numbers, could there be a similar constant that has all the properties of $e$, but is not $2.7182\ldots$?

Potentially related-questions, shown before posting, didn't have anything like this, so I apologize in advance if this is a duplicate.    I know there are many ways of calculating (or should I say "ending up at") the constant e.  How would you explain e concisely?  It's a rather beautiful number, but when friends have asked me "what is e?" I'm usually at a loss for words -- I always figured the math explains it, but I would really like to know how others conceptualize it, especially in common-language (say, "English").     related but not the same:


I understand that this may be a duplicate question. However, none of the answers to the relevant questions convinced me.  My question is that: why C++ allows forward declaration of class but not enum?  I understand that if you specify the underlying type of the enum or use enum class in C++, you can forward declare enum type. But why does C++ needs to know the size of underlying type?  enum E; void foo(E e); // Error  class C void bar(C c); // Correct, Compiler doesn't know the size of class C either.

I'm trying to do something like the following:  enum E;  void Foo(E e);  enum E {A, B, C};   which the compiler rejects.  I've had a quick look on Google and the consensus seems to be "you can't do it", but I can't understand why.  Can anyone explain?  Clarification 2: I'm doing this as I have private methods in a class that take said enum, and I do not want the enum's values exposed - so, for example, I do not want anyone to know that E is defined as  enum E {     FUNCTIONALITY_NORMAL, FUNCTIONALITY_RESTRICTED, FUNCTIONALITY_FOR_PROJECT_X }   as project X is not something I want my users to know about.  So, I wanted to forward declare the enum so I could put the private methods in the header file, declare the enum internally in the cpp, and distribute the built library file and header to people.  As for the compiler - it's GCC.


math.stackexchange community. I have joined to inquire on a hypothesis a friend of mine has recently proposed. Please note: before posting this, I have repetitively told him that his logic is flawed in a plethora of ways. But I'll humor him, just this once.  This dear friend of mine claims that when [sic] divided by zero, infinity equals all real numbers, or as follows: ∞ / 0 = (-∞, ∞)  Oh, my fellow mathematicians and logicians, please inform my friend of either his grave error or his genius discovery. Thank you.

I came up some definitions I have sort of difficulty to distinguish. In parentheses are my questions.   $\dfrac {x}{0}$ is Impossible (  If it's impossible it can't have neither infinite solutions or even one. Nevertheless, both $1.$ and $2.$ are divided by zero, but only $2. $ has infinite solutions so as $1.$ has none solution, how and why ?) $\dfrac {0}{0}$ is Undefined and has infinite solutions. (How come one be Undefined and yet has infinite solutions ?) $\dfrac {0}{x}$ and $x \ne 0$, it's okay for me, no problem, but if someone else wants to add something about it, feel free to do it.


In particular, lower light.  I will be shooting plays and other stage performances.  Low light.  Really not good light at all until their lights are upgraded.  I know I can't expect miracles, but how can I calculate what shutter speed to use to stop the subjects?  I can't see good enough to tell if the subject is blurred on the LCD screen.  Everything looks good on a screen that small.  I'm thinking of buying a Nikon D90, if that matters.  Don't know what ISO I'd need.  The subjects will be from 15 - 40 feet away, but mostly 15 - 20.  I cannot use flash.  Lens will be 1.8 - 2.8 (either a prime or a Tamron zoom).  Typically children, but some are older high school kids.  I don't know how far I need to be or what focal length is needed at a give distance to fill the frame with a 6'tall person.  Those are all the variables I know.  Thanks for any advice.

I find that taking pictures where the subject is in motion (people, pets, toy helicopters) I get a blur where there is movement.  On the other hand I see images of a drop of water in free fall in perfect clarity.  How fast does the shutter need to be to capture action in motion with perfect crisp clarity?  For example I want to catch a dog shaking himself dry after a swim and not get a bury mess but to see the hairs flying and water frozen in the air as it flies off the dogs fur and makes a giant mist around the dog.


I'm an Ubuntu newbie. Can anyone tell me how to set up PGP on Thunderbird today? It looks like it may have changed.  Should I download more of the canonical apps (an option in software setup)?

As everybody knows, emails are being read and stored. I don't like that so much and installed Enigmail, which enables PGP-encryption for emails in Thunderbird. It took me two days to install and understand the details.  Now that it is working I get aware, that I will never really use it, because my family, friends and clients aren't really interested in generating public and private keys. So I won't be able to send any encrypted messages, nor will receive them.  I'm searching for a simple way to encrypt emails in Ubuntu, without having to bother other people with "strange" petitions about software they would have to install to read my emails.


Spent several hours trying to find the right answers... and testing codes..  Just switched my site from Dreamweaver html site to a wordpress site to keep up with the Google mobile restrictions. I now need to create 301 redirects for individual pages, however the redirects are to a subdomain with pages generated automatically through an IDX provider (real estate).  For example I want to 301 redirect one page:   http://example.com/Andalucia_Homes_for_Sale.html   to   http://search.example.com/i/andalucia-apollo-beach-florida   using the htaccess file.

This question is here so we can offer users who are looking for information on how to make one or more common or basic redirects in Apache using the htaccess file. All future questions pertaining to finding information that is that is covered by the question should be closed as a duplication of this question. .  Whats the point in this question? The idea while not perfect is catch the most commonly asked questions regarding redirects using the  htaccess on the Apache platform either on  some type of lamp or a live server. The type of answers should be generally those that you could imagine are used by 100,000’s of sites world-wide and are constantly asked here at Pro Webmasters repeatedly over and over in various forms.  A few examples of the type of answers we are looking for:   How can I redirect non-www to www? How can I redirect a sub domain to the main domain? How can I redirect a sub folder from domain to a root or a subdomain?  How can I redirect an old URL to a new URL?   A few examples of the types of answers that we are not looking for:   Answers that do not involve a redirect. Any answers relating to NGinx, IIS or any other non-Apache platform. Answers that involve custom and complex string or query removals.   Resources for Advanced to Complex Mod_Rewrite Rules:      Please note: that this question is still in construction and may need some refining either by myself or a real moderator of Pro Webmasters, if you have any concerns or questions .


I was reading  on fermentation temperature control where it says,     However, since yeast growth and fermentations are exothermic and therefore generate heat, figure that the temperature within the fermenter can be as much as 8 °F (4 ºC) higher than outside of the fermenter during the early days of fermentation. So beers that are fermenting in refrigerators set at 65 °F (18 ºC) are most likely fermenting at about 72 °F (22 ºC).   4 ºC is a huge difference!  Right now I have a carboy in a fridge that's temperature controlled to 19 ºC (on the lower side of the optimal range for WLP351). The sensor strip is taped to the glass of the carboy, and consistently reading 19.2 ºC.  I'm wondering if next time I should set the temperature control lower in the first 12 hours, but I realize I have no idea how that translates to change in different sections within the carboy—near the glass, the bottom, the top (where ale yeasts float, correct?), and so on. For example even if it's 19.2 ºC on the outside of the glass, the liquid touching the inside of the glass is probably much warmer due to convection.  Is there a gradient diagram or some rough formula that would help me determine the effective fermentation temperature (where the yeast actually is) from the outside glass temperature? Or, do I have to find a way to stick a (sanitized) sensor strip into the carboy.

What's the best method to use a temperature controller during fermentation? If you're using a freezer (or warming apparatus) connected to the controller, how do you compensate for the fact that the wort's interior temperature can be several degrees higher than the air temperature around the fermentor?  In  about temperature control inside a freezer, mdma stated:     Finally, if you want to be really sure what your fermentation   temperature is, it's best to add a thermowell and a separate   thermometer. Don't be tempted to use the controller thermometer to   both measure and control the wort temperature - the wort changes   temperature very slowly, and the controller will overshoot massively,   causing everything else in the freezer to be frozen.   This was enlightening to me. I just bought a temp controller and until reading this post I had been planning to put the controller probe into the thermowell. If I understand what mdma is saying, because the relatively dense mass of the wort will not change temperature as quickly as the surrounding air, by the time the probe in the thermowell has reached the target temperature, the air surrounding the fermentor will have dropped considerably farther. Then the ambient temp will continue to chill the wort itself, resulting in a lower-than-expected wort temp and wider swings in temp as the controller cycles cooling on and off, thus defeating the goal of maintaining a consistent temperature.  (Side note: I suspect that when fermenting ales at room temperatures, the rest of the freezer is unlikely to get all the way down to freezing temperatures, but it would still be a significant variance.)  So how do you balance between air temp and wort temp? Do you just keep an eye on it and adjust the controller if the difference is significant? How much do you compensate between air temp and wort temp?


We have deleted approx 200000 tables and after which we ran Database shrink from GUI. But still database size shows almost 1 TB. Any solution?

I know shrink is the devil: It reverses page order and is responsible for skin cancer, data fragmentation, and global warming.  The list goes on... That being said, say I have a 100 GB database and I delete 50 GB of data -- not on one table, but a general pruning of old data on a database wide level, covering 90% of the tables -- does this constitute an appropriate use case for shrinking the database?  If not, what are the appropriate steps to take to clean house after removing such a high percentage of data from a database?  I can think of two: Rebuild Indexes and Update Stats. What else?


When I open an app and then I'm dong using it I usually just push the home button. The problem is that leaves the app open and if you do that too many times it slows down your phone. My question is what is the correct way to close an app after you're doing using it without pressing the home button?  Or is pressing the home button and then sliding it away the correct way of closing an app?

I'm new to the Android platform, and this is probably a dumb question, but...  How do you close an app?  When I'm in an app, and I want to get out, I just click on "Home" and move on, but I just installed a Task Manager app, and I noticed everything is left running.  Is there a way to exit apps? Or do I need to use the Task Manager every time I exit something?


How do I fix this so that i get to use the GUI desktop.  I want to run ubuntu 17 from the disk.

I am trying to boot Ubuntu on my computer.  When I boot Ubuntu, it boots to a black screen.  How can I fix this? Table of Contents:


In the case specified on the title, which answer will receive the bounty? What if a bounty question has just one answer? Will it get the bounty worth?

It's possible to offer and award bounties of reputation on questions.   What is a bounty? How can I find questions that have a bounty attached? How do I start a bounty? When can I start a bounty? Why is the system requiring me to choose a bounty amount that's higher than the minimum? Can I use Markdown formatting in the bounty remarks? Can I edit the remark? How long is the bounty period? How do I award a bounty? Can I award a bounty to my own answer? Can I award a bounty to an old answer? If I offer a bounty on someone else's question, can I award the bounty to their answer? After awarding the bounty, can I remove it or move it to another answer at a later time? What happens if there's no answer after the bounty period? What happens if I feel my question is still unanswered? What is automatic awarding? Are bounty awards exempt from the 200 points/day reputation limit? How does Community Wiki mode affect bounties? How does user deletion or post dissociation affect bounties? Can I award a bounty to an answer from a deleted user or one where the author was dissociated? Can I offer a second bounty after the first one has expired? Can I raise my bounty? What happens if a bounty question is closed or deleted? Why can't I vote to close or migrate a bounty question? What happens if I delete my account while I have an active bounty? Do I keep an awarded bounty when I delete my answer? What happens if a question where I awarded a bounty later gets deleted or migrated? Can I cancel my bounty? Can I affect / divide / share part of my bounty to two (or more) users? How many outstanding bounties can a single user have?      See also:  in the Help Center


Hi everyone!  I hope you can lead me in the right direction. I'm want to transition into QA but , I'm not sure where to start. I'm really sorry if this is the wrong place to ask, I did try another place but wasn't getting any responses, so I hope this is ok.  I'm pretty much self taught with Ruby & Python, I've heard that it would be helpful in my search for a QA job and beyond.  What are some good materials to read? Or is good place to learn more online? Also has anyone heard about   I have a basic web stack whilst learning so Ruby, Rails, Javascript, Rspec, SQL, I've played around with minitest also, and some of the basic of TDD. With Python I was using it more for data analytics so matplotlib, numpy, and pandas. Would any of this be helpful in learning more about QA?  I was thinking I should learn about manual testing first then auto is that a good route or not? Also should I focus more on Python instead of Ruby; or something else I would like to stay with those two, but I've heard java might be useful...though we haven't gotten along since highschool.  Any other help or info is much appreciated. Thanks!

I've around 10+ years of experience in Banking operations including  reconciliations, sales, customer services, asset management, and financial transaction QA.  Coming to academics I've done my PG in commerce (costing, auditing, banking, and statistics) also a diploma in project management, ISTQB foundation, Prince 2 foundation and ITIL foundation.    Can any one advise me if the testing role is ideal for me and how to start with it.


I have this exercise: Let $X_i, i\in I$ be non-empty topological spaces with I some index set. Let $(x_n)_{n\in\mathbb{N}}$ be a sequence of points in the product space $\prod_{i \in I}X_i$. Let x be another point in $\prod_{i \in I}X_i$. For every $i\in I$ let $\pi_{X_i}:\prod_{j\in J}X_j\to X_i$ denote the projection onto the the $X_i$ component. I have to show that $(x_n)_{n\in\mathbb{N}}$ converges to x (wrt. the product topology) if and only if for every $i\in I$ the sequence $(\pi_{X_i}(x_n))_{n\in\mathbb{N}}$ converges to $\pi_{X_i}(x)$ in $X_i$. I have shown $\Rightarrow$, but I have a hard time showing $\Leftarrow$. I am thinking that I have to show that for every neighborhood U of $\pi_{X_i}(x)$ there exists an $N\in\mathbb{N}$, such that for all $n\geq N$ we have that $\pi_{X_i}(x_n)\in U$, but I am not sure how to do so. Furthermore I have to show which one of the directions holds when we equip $\prod_{i \in I}X_i$ with the box topology, and then find an example to show that the other direction does not always hold when we use the box topology. I am thinking that it's the direction $\Rightarrow$ which holds for the box topology, but I have a hard time showing this, and for which example wouldn't $\Leftarrow$ hold, when we have a box topology?

question is regarding the same problem. I wish to present my proposed solution and get feedback on my argument, and as such, I claim that it is not a duplicate. (In particular, the other asker actually knew what he was doing, so this question will probably be sufficiently different. It also includes the discussion about the box topology, which the original question lacked.) We are given that $\{x_n\}$ is a sequence of points in the product space $\prod X_\alpha$. We are to show that this sequence converges to $x$ if and only if $\{\pi_\alpha(x_n)\}$ converges to $\pi_\alpha(x)$. Moreover, we are to determine if this holds if we equip $X = \prod X_\alpha$ with the box topology. We first show $\implies$. Suppose, for the sake of contradiction, that $\{\pi_\alpha(x_n)\}$ does not converge to $\pi_\alpha(x)$ for a fixed $\alpha$. Then there exists an open set $U_\alpha$ containing $\pi_\alpha(x)$ such that $X_\alpha - U_\alpha$ contains infinitely many $\pi_\alpha(x_n)$. Since every projection in the product topology is continuous, $\pi^{-1}(U_\alpha)$ is open in $X$. This contradicts the assumption that $\{x_n\} \to x$, since we now have an open set of $X$ where one of the $\{x_{n_i}\}$ clearly do not converge, where $\{x_n\} = (\{x_{n_1}\},\{x_{n_2}\},\cdots)$ We proceed to show $\impliedby$. We are given that $\{\pi_\alpha(x_n)\} \to \pi_\alpha(x)$ for every $\alpha.$ Let $\prod U_\alpha$ be an open set in $X$ containing $x$. By the definition of the product topology, we know that $U_{\alpha} \ne X_\alpha$ for only finitely many $\alpha_1, \alpha_2,\cdots,\alpha_k$. Now, since we know that $\{\pi_\alpha(x_n)\} \to \pi_\alpha(x)$, it follows by the definition of convergence that there exist numbers $N_{\alpha_1},N_{\alpha_2},\cdots,N_{\alpha_k}$ such that $\pi_{\alpha_i}(x_n) \in U_{\alpha_i}$ for $i \in \{1,\cdots,k\}$ and $n \ge N_{\alpha_i}$. Letting $N = \max\{N_{\alpha_1},\cdots,N_{\alpha_k}\}$, we see that $x_n \in \prod U_\alpha$ for $n \ge N$. (Recall that for $\alpha$ not in the finite collection, it equals the whole space $X_\alpha$, where inclusion is trivial.) We conclude that $\{x_n\} \to x$ Lastly, we consider $X$ with the box topology. In $\implies$ we did not use any particular properties of the product topology, aside from the continuity of projections, which also holds for the box topology. As such, I claim that $\implies$ still holds. However, I claim that $\impliedby$ does not hold. I ask for an example that shows this, since I am not able to find any argument I'm happy with. ("Well, our proof used properties of the product topology, so..." is only acceptable for my private notes.)


I am reconnecting nodes to create a glass effect. I'm following a tutorial and he has connected nodes and not explained what he has clicked on to bring it up. I can't find the Add box in blue.

A lot of people recommend to use the maximum node for glass setup, but I can't find that node. Nothing comes up when I search for it.  Where do I find it?


I'm trying to create command which is doing "ssh -> sudo su -> auto type password to sudo -> I have bash running under root"  I run this command ssh -t myuser@host "echo 'myuserPassword' | /usr/bin/sudo -S /bin/bash -l" I want it result in login as root and keep bash running. But instead I'm getting error:  stdin: is not a tty   Please how to fix this error and make it work?  Or any other way to auto login with sudo password?  Thanks.

I'm writing a C Shell program that will be doing su or sudo or ssh. They all want their passwords in console input (the TTY) rather than stdin or the command line.  Does anybody know a solution?  Setting up password-less sudo is not an option.   could be an option, but it's not present on my stripped-down system.


I am following Das' Finite Temperature Field Theory and the discussion of the effective potential. Das defines, \begin{equation} S^J = \int d^4x \left[ \frac{1}{2}\partial^\mu\phi\partial_\mu\phi - \frac{1}{2}m^2\phi^2 - \frac{\lambda}{4!}\phi^4 + J\phi \right] = S + \int d^4x\ J\phi. \end{equation} The generating functional is naturally, \begin{equation} Z[J] = e^{\frac{i}{\hbar}W[J]} = \int\mathcal{D}\phi e^{\frac{i}{\hbar}S^J} . \end{equation} From the equations of motion, we have \begin{equation} (\square + m^2)\phi + \frac{\lambda}{3!}\phi^3 - J = 0. \end{equation} We will denote this as $F(\phi) = J$. Now, consider $\phi\to\phi + \delta\phi$. We naturally know then that $\delta Z[J] = 0$. Therefore, \begin{align} 0 &= \int \mathcal{D}\phi\ \frac{\delta S^J}{\delta \phi}e^{iS^J}\\[0.25cm] &=  \int \mathcal{D}\phi\ (F(\phi) - J)e^{iS^J}\\[0.25cm] &=  \int \mathcal{D}\phi\ \left(F\left(\frac{i}{\hbar}\frac{\delta}{\delta J} \right) - J\right)e^{iS^J}\\[0.25cm] &=  \left(F\left(\frac{i}{\hbar}\frac{\delta}{\delta J} \right) - J\right)Z[J] . \end{align} In terms of $W[J]$, \begin{equation} e^{-\frac{i}{\hbar}W[J]}F\left(\frac{i}{\hbar}\frac{\delta}{\delta J} \right)e^{\frac{i}{\hbar}W[J]} = J(x) . \end{equation} Das then goes on to say that this is equivalent to, \begin{equation} F\left( \frac{\delta W}{\delta J(x)} + \frac{\hbar}{i}\frac{\delta}{\delta J(x)} \right)  = J(x) \end{equation} where "here, we are assuming that the functional derivative, after simplification, actions on the identity on the right." I am not sure how this final result is obtained. I would appreciate any input.

In the book of Ashok Das, Field theory-path integral approach, he begin the demonstration of the Schwinger-Dyson equation using the fact that the $\delta Z[J]=0$, so  \begin{equation} \delta Z[J]=\int \mathcal{D} \phi \frac{\delta S[\phi,J]}{\delta \phi(x)} e^{iS[\phi,J]}=0, \end{equation} but we already know that  \begin{equation} \frac{\delta S[\phi, J]}{\delta \phi(x)}=F(\phi(x))-J(x), \end{equation} where $F(\phi(x))$ is the equation of motion.   So if we go back to the first equation and use the identification  \begin{equation} \phi(x)\rightarrow -i\frac{\delta}{\delta J(x)}, \end{equation}  we conclude that  $$ \int \mathcal{D}\phi\left(F(\phi(x))-J(x)\right)e^{iS[\phi,J]}=\left(F\left(-i\frac{\delta }{\delta J(x)}\right)-J(x)\right)\int \mathcal{D}\phi e^{iS[\phi,J]} $$ $$ \left(F\left(-i\frac{\delta }{\delta J(x)}\right)-J(x)\right)Z[J]=\left(F\left(-i\frac{\delta }{\delta J(x)}\right)-J(x)\right)e^{iW[J]}=0. $$  But is here where I get lost, how did he pass from the above equation for  $$ e^{-iW[J]}\left(F\left(-i\frac{\delta }{\delta J(x)}\right)-J(x)\right)e^{iW[J]}=F\left(\frac{\delta W[J]}{\delta J(x)}-i\frac{\delta}{\delta J(x)}\right)-J(x)=0. $$  A more important question is: what does this last equation mean at all, mathematically speaking, because the functional derivative now is acting on nothing.


I got error when removing one of the element in my list of (list of integers). I use iterator to remove that element  Here is my code:  List<List<Integer>> list = new ArrayList<List<Integer>>(); .... .... Iterator<List<Integer>> myListIterator = list.iterator(); int ct1 = 0; while (myListIterator.hasNext()) {     List<Integer> val = myListIterator.next(); // here is the error      if(ct1 == val.get(0))         list.remove(val);     ct1++; }   And I got this error message:  Exception in thread "main" java.util.ConcurrentModificationException     at java.util.ArrayList$Itr.checkForComodification(Unknown Source)     at java.util.ArrayList$Itr.next(Unknown Source)   Does anyone know what's wrong with my code? Thank you guys!

We all know you can't do the following because of ConcurrentModificationException:  for (Object i : l) {     if (condition(i)) {         l.remove(i);     } }   But this apparently works sometimes, but not always. Here's some specific code:  public static void main(String[] args) {     Collection<Integer> l = new ArrayList<>();      for (int i = 0; i < 10; ++i) {         l.add(4);         l.add(5);         l.add(6);     }      for (int i : l) {         if (i == 5) {             l.remove(i);         }     }      System.out.println(l); }   This, of course, results in:  Exception in thread "main" java.util.ConcurrentModificationException   Even though multiple threads aren't doing it. Anyway.  What's the best solution to this problem? How can I remove an item from the collection in a loop without throwing this exception?  I'm also using an arbitrary Collection here, not necessarily an ArrayList, so you can't rely on get.


Consider the function $f:[0,1]\to\mathbf{R}$, with    $$f(x)=\begin{cases}\frac{1}{b} ,\quad x=\frac{a}{b}\in[0,1]\cap\mathbf{Q},  \ (a,b)=1 \\ 0 , \quad x \in [0,1]\cap\mathbf{Q}^{c} \text{ or } x=0 \end{cases}$$      Prove that $f$ is continuous for every $r\in [0,1]\cap\mathbf{Q}^{c}$   Could I have some kind of hint or help?

In :  $$ \begin{align} t(x) = \begin{cases} 0 & \text{if $x$ is irrational}\\ \frac{1}{n} & \text{if $x = \frac{m}{n}$ where $\gcd(m,n) = 1$} \end{cases} \end{align} $$  I can prove the discontinuity at rational $b$ by taking a sequence of irrationals $x_n$ which converge to $b$.   But while going through an argument for continuity at irrationals.  I found this in a book.      On the other hand if $b$ is an irrational number and $\epsilon > 0$   then there is a     natural number $n_0$ such that $1/n_0 < \epsilon$.   There are only finite number of rationals with denominator less than   $n_0$ in the interval $(b-1,b+1)$. Hence we can find a $\delta > 0$   such that $\delta$ neighbourhood of $b$ contains no rational with   denominator less than $n_0$.   I understand the rest of the proof. But I am unable to prove the emphasized text. Although I find it intuitive.


I tried searching for the answers and it says that when you say at it generally talks about the location. When we say in it talks about when you're inside that place. I just don't know which one is better. I hope you can help me.

There are a lot of posts on this topic, but I can't find any answers to my question.  I came across the following two definitions of 'school':        [uncountable] (used without the or a) the process of learning in a   school; the time during your life when you go to a school (British   English)   [uncountable] (used without the or a) the time during the day when   children are working in a school      Source:   I know there are better ways to convey the message, but which sentence would a teacher utter if he was a school teacher teaching students, adults, etc.? What about a janitor, director, and secretary?     I teach at/in school OR I teach at/in a school   The above definitions concern students, and not working individuals like teachers or janitors.  I would appreciate if you also stated whether you're American, Canadian, British, etc.


As I was going over the Review Close Votes Queue I came upon a  that seemed familiar.  When I tried to vote to close the question (as duplicate) I got a message saying that I already flagged this question for closure.   I checked my flags, and indeed found a duplicate flag for this question, which was deemed helpful (at the time of flagging that question I didn't have 3K rep, so I couldn't cast a close vote).  My question is why can't I vote to close this question? I never voted to close it. I just flagged it. I assume the person who handled the flag decided to follow my suggestion to close the question as duplicate and cast a close vote (the question currently has one close vote), but that wasn't my close vote.  And if you convince me it's the desired behavior not to let me vote to close that question, then that question shouldn't have appeared in my Close Votes Queue in the first place.

Back in April, I flagged a post as "not a real question".  The post was subsequently closed and reopened, then closed again and finally just reopened a 2nd time a short time ago.  I still firmly believe the post is not acceptable for SO, so I went to use my recently acquired close vote privilege and was greeted with the following messsage:    I specifically clicked close and not flag (and figuring I just clicked in error, I tried again and got the same message).  I do understand that, in the new closing system, flagging for closure is treated very much like a close vote (since it throws it to the close vote queue) except no vote is actually recorded.  My issue is why should by flag be counted as a close vote when I never actually voted to close.


I would need some help in understanding if my wife (who is an Indonesian) can still be granted access to Singapore after being previously denied entry (and was also detained for about 30 days due to usage of 2 passports with different names more than 6 years ago).  if we come to Singapore now, what shall we put in the embarkation card questionnaire that requires input of whether she has been denied entry before ? (shall we tick Yes ?); on the question of using a different passport (shall we also tick Yes ?).  Is there a possibility that re-entering Singapore will risk my wife being detained again based on the background I provided above ?  pls advise.  Respecfully, Budi

My friend who is an Indonesian citizen tried to enter Singapore this week and was refused entry at the Singapore Harbour Front Ferry Terminal by immigration.  This was his first trip overseas and is not used to international travel, so due to his inexperience and that he was excited to go to Singapore, he possibly made some mistakes on trying to be granted access into Singapore.   He was told he was to enter a Singapore address for his stay or a friend or relative he will stay with. He was only staying for one day and was going to catch the ferry back at night, so he had no plan to stay in Singapore and as such had no address to put. They then asked why he was traveling alone and that he should travel with somebody for his first trip. He told them he always travels alone in Indonesia and finds it easier to see and do things alone. He was then asked why he was entering Singapore and the reason he gave was to purchase some electronics which he cannot buy in Indonesia. They asked for how much money he had and they then advised that he did not have enough money to purchase the items he was after. They refused his entry and he was then escorted to a ferry and returned to Indonesia. His passport was not stamped and he was not fingerprinted.   He was given a Notice of Refusal of Entry which had the reason as "Being ineligible for the issue of a pass under current immigration policies" form on his departure. Also included on this form is his passport number etc. He was not advised of him being banned or a time frame that he cannot enter Singapore.  My questions are: Has he been banned or restricted to enter Singapore for a period of time? When entering countries including Singapore, does he need to tick the box stating he has been refused entry into another country? I am hoping to get my friend to Australia at the end of the year for a 10 day holiday and will this hinder his chance of getting a visa and entering Australia?


So for my university final assignment I'm doing a procedural world generator in unity. The idea is that different types of terrain are generated such as ocean, swamp, hills etc. I have the different biomes generating as chunks with different colours at the moment and the next step for me is to smoothly transition between them rather than drop off from one terrain type to another. To do this I'm going to need to adjust the heightmap so that the edges join together rather than having gaps between them. The noise is continuous so biomes of the same type connect seamlessly. However with different biomes the height generated from any given noise is different, that way my mountains stick up without my ocean chunks being weird shapes. The result is like I said earlier, there are seams between my chunks that I need to stitch. So my real question is what approaches are there currently to blend from one height map to another?

I want to generate a procedural world using perlin noise. As expected, my terrain is generating with a repetitive patern. I'd like to add biomes, zones separated with higher or lower amplitude to simulate mountains or plain. I first thought I could randomly select rectangles of verticesof random sizes and then give them bigger amplitude to simulate mountains. The problem with that is that It wont seem natural, since I will only have rectangle biomes and also I don't know how to make it so the mountains would connect with the plain to avoid things like this Here is my script: public int size = 10; public float amplitude; public float frequence; void GenerateTerrain(float amp, float freq) {     Mesh meshy;      MeshRenderer meshRenderer = GetComponent<MeshRenderer>();     meshRenderer.sharedMaterial = new Material(Shader.Find("Standard"));     MeshFilter meshFilter = gameObject.GetComponent<MeshFilter>();      List<Vector2> uv = new List<Vector2>();     Vector3[] vert = new Vector3[size * size];     List<int> tri = new List<int>();     List<Vector3> norm = new List<Vector3>();     meshy = new Mesh();       for (int i = 0, x = 0; x < size; x++){         for(int z = 0; z < size; z++){             float y = Mathf.PerlinNoise(x * amp, z * amp) * freq;             vert[i] = new Vector3(x, y, z);             i++;}}       for (int i = 0; i < vert.Length; i++){         norm.Add(-Vector3.forward);}       for (int x = 0; x < size - 1; x++){         for (int z = 0; z < size - 1; z++){             int i = size * x + z;              tri.Add(i);             tri.Add(i + 1);             tri.Add(i + size);             tri.Add(i + size + 1);             tri.Add(i + size);             tri.Add(i + 1);}}       for (int i = 0; i < vert.Length; i++){         uv.Add(new Vector2(vert[i].x, vert[i].z));}      meshy.vertices = vert;     meshy.triangles = tri.ToArray();     meshy.uv = uv.ToArray();     meshy.normals = norm.ToArray();     meshFilter.mesh = meshy; }  void Update() {     if (Input.GetKeyDown("u"))         GenerateTerrain(frequence, amplitude); }


On Terraria Console Version I killed The Twins And destroyer.   But! the Steampunker NPC Wont move in, I do have Jungle, Normal, Hallow in my house, how ?   What am I doing wrong?  What went wrong?   Is it only for PC version?

I can't make the steam punker move into my house! Even though i killed a mechanical boss, removed the Hallow from my house, and the house is suitable, she isn't moving in. Could someone please help me? I just don't know what went wrong!


Hello I am having a some difficulty with a very simple program.  import java.util.*; public class Compare {     public static void main( String args[] )     {          String username;          Scanner input = new Scanner(System.in);          String users[] = {"John", "James", "Smith", "Paul"};           System.out.println("Please Enter Username: ");          username = input.next();           for( int i = 0; i < users.length(); i ++ )          {                if( users[i] == username )                   System.out.println("Match");                else                   System.out.println("No Match");          }     } }   When I run this program I get No Match which I don't know how is possible when I enter the same string as on of the strings in the users array. Any Suggestions?

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?


Is there a way to make windows xp bootable pendrive in ubuntu.  I have seen winusb but it seems that it only supports winvista and win7.

I'd like to create a Windows bootable USB stick, but I don't have a Windows machine with me at the moment to do so. How could I achieve the same using Ubuntu?


The following is an exercise from Topology by Munkres.      Let $X=\{0,1\}$, $X^\omega=\prod\limits^\infty X$, and $B=\{\text{all countable subsets of $X^\omega$}\}$.    Show that $|X^\omega|=|B|$.    My attempt: I can't seem to find a particular bijection, so I want to use Schröder-Bernstein and find two injective functions using each set as its domain and range, respectively.  It is easy to see that the function $f:X^\omega\to B$ defined as $f(x)=\{x\}$ is an injection. However, I can't seem to find a function $g:B\to X^\omega$ that is injective.   Any help is appreciated.

Suppose that $\;f_1,\;f_2:\;A\to B$ such that $f_1$ is injective and $f_2$ is surjective.   I was trying to find out whether there exists $f_3:\;A\to B$ such that $f_3$ is bijective. Is it possible to construct it from $f_1$ and $f_2$?  I tried proving the statement non-constructively via a cardinality argument, but ended up hand-waving a lot (i.e., since the cardinality is the same, there exists a bijection, a bit of circular reasoning). But, I'd be more interested in a construction based argument, as I can't think of one.


I've heard of a trick called "En passant" but what does it mean?

How useful is that rule and how many times we can use that in one game?  Under what conditions can the en passant rule be used?  How often does it come up and is it a good idea to use it?


I have a big work trip planned to the US in 3 weeks. I am worried about this autograph on one of the visa pages.  Has anyone ever had issues with this sort of thing, or any ways around it? I don't have enought time to get a new passport.

I chanced on an  today, featuring a guy who likes to draw artwork into passports. The article claims that the passports still work without an issue.  Now I am pretty sure my passport says something like 'no manual annotations can be made without rendering it invalid', so I am a little sceptical about that article.  Has anyone experience on how drawing into one's passport effects its validity and how much that is enforced?


I have created a string of integers like this:  var whereClause = "4,5,6"   I need to use this in the following SQL where clause, where message.Id is an int col  select * from table a where message.Id in (@whereClause)   Running this throws Conversion failed when converting the nvarchar value '4,5,6' to data type int.  How would one cast the string, so that it could be used in a WHERE IN clause?  EDIT Appreciate this could possible be a repeat of a question, but I am using Dapper.NET and couldn't find any examples

How do I parameterize a query containing an IN clause with a variable number of arguments, like this one?  SELECT * FROM Tags  WHERE Name IN ('ruby','rails','scruffy','rubyonrails') ORDER BY Count DESC   In this query, the number of arguments could be anywhere from 1 to 5.  I would prefer not to use a dedicated stored procedure for this (or XML), but if there is some elegant way specific to , I am open to that.


Admiral Gonzeles told his men to search for a gun. A soldier asked if the admiral had any further instructions.  Should the second time admiral is used be capitalized or not?  Thanks  Frank

Please excuse the contrived example below, but I am wondering if this example is properly capitalised? I'm assuming that capitals are used when addressing someone directly, but lower case is used elsewhere. Can someone give some rules on this?      The captain walked into the room.    "Hi, Captain," said the admiral.   "Hi, Sir," replied the captain.   "Call me Admiral."   "Hi Admiral."   The captain and admiral stepped forward.   "Prime Minister, this is Captain Jones," said Admiral Brown.   "Pleased to meet you," said the prime minister.


I have an extra wire I can use for the C wire on both ends but in my attic the main unit has a wire already attached to the C spot and going away from the unit to something else. Can I attach two wires to the c terminal?

TL;DR: Can you terminate more than one common on the furnace C terminal?   Background:  I've linked a diagram of how my non-programmable thermostat is currently hooked up. I want to replace it with a Trane Z-Wave thermostat that requires constant power. There's already a blue wire in the 18/5 bundle, but it's disconnected on both ends. The C terminal on the furnace control board is already in use by the rooftop condenser. If possible, I'd like to connect the blue wire to the stat and terminate it on the same C terminal on the furnace that is already in use by the A/C.    Some model numbers:   Furnace: Goodman GKS9 Gas Furnace with A/C (CAPF) -  Old stat: Honeywell TH3210D1004 non-programmable New stat: Trane TZEMT400BB3 Z-Wave


We are traveling to Canada on 7/2/19. My 19 year old son did not get his passport (they screwed up twice). Is there any way he can still travel with us to Canada and back? We are traveling by car to Toronto from New York.

If I am a US citizen, do I need a passport to go visit Canada at Niagara Falls for 3 days and then reenter the USA?


Similarly between "Last month" and "The last month".   Last week implies, at some point during the previous week. Not inclusive of the current week.  What exactly does the last week mean? Is that inclusive of the current time? Same question for the last n weeks?   Or are phrases ending with ago the only qualifier for being for being inclusive of the current week? A month ago pretty obviously implies a period of 30 days going back from current time.  Thanks in advance!

I would have question related to other question I asked today. I know that:   last year refers to something that happens in the last year (which could be yesterday if today is 1.1.) the last year — means the last 365 days including today.   But what about "for the whole of the last year" and "for the whole of last year"? In an answer I received it is mentioned that this "of" disctincts between last year and last 12 months, which I thought is done by "the"?


On my thl 4000 I can't install apps - I get 'insufficient storage' massage, but I have 168M of free storage and the apps are 2 - 8 M  I tried to follow all the instructions on the different forums, it helped at first but now nothing works.  android v - 4.4.2

After one of the latest updates (not sure if it was the last one or a previous one) of the Google Play app, I am having an error trying to update a large app (42MB). It says:     Error Downloading . There is insufficient space on the device.   My device is a Samsung P1000 running Froyo. It's rooted, but the error was there before rooting it.  A quick Google search showed several Samsung users having the same problem (the app in question that was giving me the headache is Smurf's village). Some said that removing the updates to the Android Market (Google Play) app would fix it, but to me it was of no avail.  I also tried the procedure in  to no avail.  Now I am stuck with a prehistoric version of the Market (that works on small apps) and still cannot update Smurf's Village or install big apps. How can I fix this?  EDIT: device has over 2GB of internal SD storage, 27GB of external SD card, so space is not an issue.


According to high-school physics, light frequency and wavelength are inversely proportional, and their product is the speed of light. But when discussing spectral power, somehow sunlight peaks differently in these two spaces:    How is this possible?

I read that it makes a difference whether you calculate $\frac{dE(\lambda) }{d \lambda}=0$ or $\frac{dE(\omega)}{d \omega}=0$ in the sense that the maximum energy density with respect to the wavelength does not coincide with the frequency maximum that one would assume to be at $\omega_{max} = \frac{c}{\lambda_{max}}$. Actually, I do not understand why this is so ( Now, I am only interested in a pure physical explanation, mathematically this is clear and due to the chain rule). Does anybody know how to explain this odd thing?  Somehow I feel that the core of the question has not been completely answered. Although I can easily look up wikipedia, where the need for the chain rule is explained, I am rather interested in understanding where the following argument breaks down, which seems to be why this question has caused some confusion in the past(as you can see by googling this question):  So we have $E(\omega)$ the energy radiated at a given frequency. Now this function has a maximum somewhere, so there is a frequency where a maximal amount of energy is emitted. In other words: If you add the sum of the photon's energies at each frequency that are emitted, you will notice that the maximum is reached at this frquency. Now $E(\lambda)$ tells you basically the same for the wavelength, but again: We know where at which frequency the maximal amount of energy is radiated, so we know the corresponding wavelength.   I think there is a need to explain this.   If anything is unclear, please let me know.


a)Show that the following sequence of functions is convergent.  $f_{1}(x) = \sin(x)$   $f_{2}(x) = \sin(\sin(x))$  $f_{3}(x) = \sin(\sin(\sin(x)))$  ...  $f_{n}(x) = \sin(\sin(\sin(...(\sin(x))))$ ($n$ times)  b) Find limit of the above sequence.

I need your help with evaluating this limit:  $$ \lim_{n \to \infty }\underbrace{\sin \sin \dots\sin}_{\text{$n$ compositions}}\,n,$$  i.e. we apply the $\sin$ function $n$ times.  Thank you.


I am unable to install Ubuntu 18.04.  To start things off, I see a black screen instead of installation instruction after booting the liveusb using BIOS boot (not UEFI). Not sure why this black screen but I am guessing its a graphics driver issue. I am using a newly bought amd rx560 card.  But I did however gain access to the OS by setting 'nomodeset'. Unfortunately at the end of the installation process, it failed to install the GRUB, giving me the error message shown in the title of this question.  I usually have two partitions for any linux distro: swap and root. I also leave the "Device for bootloader installation" option untouched. Which is by default /dev/sda  Please feel free to ask me any information regarding this. I really need help on this. I don't want to go back to windows after 9 years of ubuntuship.

I am installing Ubuntu 16.04 in an Intel NUC computer with UEFI enabled. I am using an SSD from another computer. During the installation I chose Erase the disk and make a new full install  At the end of the process I see:  grub-efi-amd64-signed failed installation /target/ Ubuntu 16.04    And the system does not boot.  I tried to use boot-repair but apparently it does not solve the problem.


I'm new to game development and want know how to make or load a terrain from OpenStreetMap or Google Maps in your current city. (I'm using Unity3D.)  My idea is just load or generate a map of the current location, without collisions or anything else. A good example could be the Google's game "Ingress".  I found a few tutorials but only for a static city or mountain.

I want to build a game with a concept similar to , where the game map is overlaid on a real one.  Where can I find map data for an app like that? How (generally) do I integrate my own game objects into that map? Game objects need to move in real time, so having them as static markers on the map isn't sufficient.  I thought I could use Google Maps but as far as I can tell it would be impossible to create my own graphical style (like Ingress has done) with the official API provided by Google.


Domino server receive requests with variable in header [X-Forwarded-Proto-F5]. I would like to do some tricks depends of value there (either redirect requests or not).  Is it possible to do redirects based of some variables in request's header using only IBM Domino server?  If no, what other options do I have?

Issue  I've difficulties to understand if it is possible to do redirects depends of variable in Header using Domino server (R9).  AIM  Redirect all requests (for 1 particular website) to: https://www.domain  EXAMPLE incoming requests:   http://example.com http://www.example.com https://example.com   All 3 examples should be redirected to   https://www.example.com   Here is my setup   All requests come to "Load Balancer" and then it redirect requests to Domino Server. Load Balancer always (!) convert requests from HTTPS to HTTP, so Domino always receives HTTP requests. Load Balancer adds flag/variable to requests which have been converted from HTTPS to HTTP. Domino must redirect HTTP to HTTPS. My issue - I need to figure out how to verify variable in request and depends of it - do redirect to HTTPS or NOT. So far if I set redirect for all request - I receive a loop and I understand why.   Does anybody have an idea how to solve that only with Domino Server?  Possible solutions I know about   Setup one more server between Load Balancer and Domino, so it does redirect instead of Domino. Go with DSAPI. I really would like to avoid it, it requires development + maintenance.


When running this program I get this error code thrown back:     java.lang.NullPointerException     at javax.swing.ImageIcon.<init>(ImageIcon.java:217)     at DebugMe.<init>(DebugMe.java:16)     at DebugMe.main(DebugMe.java:31)   However no errors are being thrown within the compiler itself. The "debug.jpeg" image is within the same folder that the program is being run from as well.  import java.awt.*; import javax.swing.*;  public class DebugMe extends JFrame {     private String message = "Congratulations, the program is working again.";     Image debug = new ImageIcon(this.getClass().getResource("debug.jpeg")).getImage();     int x; //Initialized x      /**      * Constructor for objects of class DebugMe      */     public DebugMe()     {         x = 0;         setSize(500, 500);         setVisible(true); //Lowercase t on true     }      public static void main(String[] args)     {         DebugMe myDebugMe = new DebugMe(); //capitalized me in Debugme         int x;     }      public void paint(Graphics g)     {         super.paint(g);         g.drawString("message", 100, 100);         g.drawImage(debug, 100, 200, Color.BLUE, this);     } }

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?


As the title, I was asked to show that $2^{44}-1$ is divisible by $89$.  My first attempt is to change the expression into $(2^{22}-1)(2^{22}+1)$.  Then further simplified it into $(2^{11}-1)(2^{11}+1)(2^{22}+1)$, I used my calculator and was able to show that $2^{11}-1$ is divisible by $89$ but then I don't know how to show it with modular arithmetic. I do think that it is quite similar to the form where we can use the Fermat's little theorem. $(\sqrt{2})^{88}-1$. (Though I do understand Flt can only be applied to integer.)  Can someone tell me whether I can take square root in modular arithmetic as well? I am still pretty new to the modular arithmetic. Thank you very much.


When I tried to set up git in my computer I encountered the following error:  E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?

I get this error when trying to use apt-get:  E: Could not get lock /var/lib/dpkg/lock - open (11 Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/) is another process using it?     How can I fix this?


I've just eliminated the /Desktop/ folder through rm -r that i shouldn't. I know there is no way to restore it but I would like to know if there is some automatic back up that I can use to restore my file. I'm using ubuntu 16.04.

Are there any tools, methods, incantations to recover recently deleted files on Ubuntu?  If it makes any difference, I want to recover a  2.x database file. But would be better to have a method/tool that works on any kind of file.


I upgraded to Ubuntu 20.04 and now my task manager is unusable because it displays a weird  icon font. How can I fix this? Thanks!

Recently, on my Ubuntu 18.04 I have noticed that at least on gnome-calculator and chromium browser the fonts are displayed as squares. I have followed instructions  and , the calculator is fixed, but the problem on chromium still exists when I open a dialog to search for a file.  Not sure if this happens on other applications as well, I haven't checked all my apps, but File managers nemo and nautilus are working fine.  Also, before few months ago, I have included some windows fonts for my libre office shown . I used the copy (cp) method, not the link (ln -s). But, was working fine until yesterday. Haven't done any major change or update, at least on my Linux partition (dual boot). But, I don't think that this has anything to do with that.  Any idea how can I fix this issue?  .


So, after around 5 minutes of idle, CPU goes to ~12% usage by process SYSTEM (PID 4), more specifically by thread called ntoskrnl.exe!ExQueueWorkItem+0x400 and after some time it ends by itself but it happens everytime I left my PC idle. If any key is pressed or the mouse moved, this stops immediately.   I have this PC for a year already and never seen this before last couple of months. So, i did clean installation of windows about two weeks ago to solve this and there was not such a problem since then but today it appeared again. I didn't make any changes in software/hardware.   I have all drivers updated, Windows 10 Home, Fall Creators Update with latest build. Despite this everything is working fine but this problem is annoying.   So what should I do?  Edit: i found out using taskschedulerview that everytime this cpu usage happen there are several processes every time the same

I have noticed that from some time my system is freezing and its probably caused by the high CPU usage which is caused by the system process.  All applications I'm running is the Skype, TeamSpeak and Chrome so it definitely shouldnt eat that amount of CPU.  You can see the problem itself and running processes in the screenshot below:    Sometimes CPU usage is reaching 90%, but the average usage is like 40-65%.  My PC parameters:   Windows 8 (customer preview) Intel Core i3 - 2350M 8 GB RAM   I'd appreciate any help attempt! Regards.  --UPDATE--  As the user below posted a great answer, I have noticed that the process that is eating the most CPU in the system is called Arthurx.sys, simple google tells that it's a TPLink driver (an wifi adapter, I have bought like 2 weeks ago!) drivers has been installed from the Windows MSDN, but also tried to install the drivers from the attached CD, but it doesn't help. From the system start, it is using like 5% of the CPU only, but after 2-4 hours of working it is growing up and reaching 40-60% of the CPU usage.  Device name: TPLink WN722N


DP-1 connected primary 1440x900+1920+0 (normal left inverted right x axis y axis) 160mm x 90mm    1440x900      59.89*+    1920x1080     60.05    60.00    50.04      1280x720      60.00    59.94    50.00      1024x768      60.00      800x600       60.32      720x576       50.00      720x480       59.94      640x480       59.94    This is the output I get from xrandr -q  $ lspci | grep VGA 01:00.0 VGA compatible controller: NVIDIA Corporation Device 1c82 (rev a1)   All of the resolutions work (are bad looking though), but the only one that doesn't work (the one I want) does not. All I get is No signal from my monitor when I do this:  xrandr --output DP-1 --mode 1440x900   Additional info:  $ dpkg -l | grep nvidia ii  nvidia-370                                 370.28-0ubuntu0~gpu16.04.2                    amd64        NVIDIA binary driver - version 370.28 ii  nvidia-opencl-icd-370                      370.28-0ubuntu0~gpu16.04.2                    amd64        NVIDIA OpenCL ICD ii  nvidia-prime                               0.8.2                                         amd64        Tools to enable NVIDIA's Prime ii  nvidia-settings                            370.28-0ubuntu0~gpu16.04.1                    amd64        Tool for configuring the NVIDIA graphics driver   Model: Samsung LE19R86BD  $ cvt 1440 900 # 1440x900 59.89 Hz (CVT 1.30MA) hsync: 55.93 kHz; pclk: 106.50 MHz Modeline "1440x900_60.00"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync $ xrandr --newmode "1440x900_59.89"  106.50  1440 1528 1672 1904  900 903 909 934 -hsync +vsync $ xrandr --addmode DP-1 "1440x900_59.89"   X Error of failed request:  BadMatch (invalid parameter attributes)   Major opcode of failed request:  140 (RANDR)   Minor opcode of failed request:  18 (RRAddOutputMode)   Serial number of failed request:  37   Current serial number in output stream:  38

After installing Ubuntu 10.04 with my Samsung SyncMaster B2030, native resolution (1600X900) is not found in the list of resolutions.