Can't launch Google Chrome in Ubuntu 14.04

I have installed the 14.04 LTS in clean. then I use wget the chrome.deb for 64 bit from Google and dpkg -i *.deb to install the chrome in my Ubuntu 14.04,however I can't launch it and get errors as below, could you please help me to solve this problem?  $ google-chrome [2697:2697:0616/211443:ERROR:process_singleton_linux.cc(394)] readlink failed: no authority [2697:2697:0616/211443:ERROR:process_singleton_linux.cc(240)] readlink(/home/frank/.config/google-chrome/SingletonLock) failed: no authority [2697:2697:0616/211443:ERROR:process_singleton_linux.cc(240)] readlink(/home/frank/.config/google-chrome/SingletonLock) failed: no authority [2697:2697:0616/211443:ERROR:process_singleton_linux.cc(264)] Failed to create /home/frank/.config/google-chrome/SingletonLock: no authority [2697:2697:0616/211443:ERROR:process_singleton_linux.cc(394)] readlink failed: no authority [2697:2697:0616/211443:ERROR:process_singleton_linux.cc(240)] readlink(/home/frank/.config/google-chrome/SingletonLock) failed: no authority [2697:2697:0616/211443:ERROR:chrome_browser_main.cc(1209)] Failed to create a ProcessSingleton for your profile directory. This means that running multiple instances would start multiple browser processes rather than opening a new window in the existing process. Aborting now to avoid profile corruption.


I have yesterday updated packages and today the system cannot boot properly. After seeing the Kubuntu logo there is a black screen which shows repeatedly.     Stopped User Manager for UID 121.      Removed slice User Slice of gdm.      Created slice User Slice of gdm.       Starting User Manager for UID 121...      Started Session c3 of user gdm.       Started User Manager for UID 121.   Please see the screenshot below


Translucency for leaves with the Principled BSDF

I was wondering, what is the correct way to set up a leaf shader using the principled shader and translucency?    Using the sss part of the principled shader gave weird results with one-sided meshes, as the backside was actually darker than the front part.  I normally just added the translucency shader to the principled, but that caused some bugs when there were many bounces between close objects, which then added itself onto another and the energy exploded (white plant).  Mixing Principled with translucency also gave weird results, as it automatically darkened the side of the leaf that was lit, if the translucent effect was strong (otherwise the translucency was simply too weak). I only used a value for the factor here, maybe there's a simple solution for what to use as a factor, but I don't know it. I also read that some people suggested using the transmission value, but this seems odd as it is for transmission and not translucency and also produced weird results.   Anyway, help would be highly appreciated, thanks in advance!


What do we call the "repetition" construct (if it's even proper English)?

I've sometimes seen this construct, used to avoid repetitive handwriting, but I don't even know if it's proper English.  If it is, what is the name of this construct? I have no idea what to search for when looking it up...        Don't forget to buy eggs.    "        "  " " yogurt.    "        "  " " milk.


Why do Calabi-Yau manifolds crop up in string theory, and what their most useful and suggestive form?

Why do Calabi-Yau manifolds crop up in String Theory? From reading "The Shape of Inner Space", I gather one reason is of course that Calabi-Yaus are vacuum solutions of the GR equations. But are there any other reasons?  Also, given those reasons, what tend to be the most physically suggestive and useful or amenable forms among the widely different expressions obtainable by birational transformations and other kinds?  Actually, just some examples of C-Ys, and what they are supposed to represent, would be very interesting.


Making code internal but available for unit testing from other projects

We put all of our unit tests in their own projects.  We find that we have to make certain classes public instead of internal just for the unit tests.  Is there anyway to avoid having to do this.  What are the memory implication by making classes public instead of sealed?


The following excerpt is from , 2nd edition, by J. N. Reddy:     4.1 CONCEPTS OF WORK AND ENERGY      Consider a material particle, moving from point $A$ to point $B$ along some path in space under the influence of a force $\mathbf{F}$, which can be time-dependent. The position of the particle is measured from a fixed origin by position vector $\mathbf{r}$. Then the work $dW$ performed by the force $\mathbf{F}$ in moving the particle by an infinitesimal distance (or displacement) $d\mathbf{r}= d\mathbf{u}$ along the path over an interval of time $dt$ is defined as   $$dW= \mathbf{F} . d \mathbf{u}=F_1du_1+F_2du_2+F_3du_3$$   In other words, work done is the product of the displacement and force in the direction of the displacement. The total work done, $W$, by the force $\mathbf{F}$ in moving the particle from point $A$ to point $B$ is given by   $$W=\int_A^B \mathbf{F} . d \mathbf{u}$$   By definition, work done is a scalar quantity, and it is positive whenever both displacement and force have the same direction and negative if they hare in the opposite directions. Since $\mathbf{u}$ depends on the chosen reference frame, $W$ also depends on the choice of the reference frame. Thus, work is a relative quantity. However, work done does not depend on the path but only the end points, $W=W_B-W_A$. If the reference frame is chosen such that $W_A=0$, then $W=W_B$.    to the page  What is he trying to say? Is he saying that work in general is a state variable? And has exact differential? I got confused! So far, all of books I have read, also all of my professors, and many other sources and expert people claim that work in general is path dependent and only in some special cases can be determined by means of initial and final states. Is there something here that I don’t consider? Is there any meaning for $W_B$? Even for those special cases we have for example:  $W=U_B-U_A$ (not $W=W_B-W_A$)  where $U$ is some kind of energy.


How do I stop my fire alarm from going off when I cook?

My fire alarm always goes off when I cook, even when the food is not burning. Because of this, I have never been able to keep batteries in my fire alarms.  How can I stop this from happening?


Is it possible to switch to a new domain name without losing Google rankings?

I have been using a domain name for the last few years. A larger company is threatening to sue me for using my initials as my company name!  So as an answer to this I have created a new domain URL with the addition of my location in the URL. So I now have redirected my old URL to my new URL.  But...I want Google to acknowledge this is really then same site and to keep any rankings, or to transfer the rankings from the old URL to the new URL!  Is this possible?


Does the renormalisation group flow actually involve a group?

I've come across the notion of a renormalisation group flow in a number of places; for example, in Dr. Tongs lecture  in QFT:     it will turn out that that the possible interactions in QFT will be governed by a few basic principles: locality, symmetry & renormalisation group flow (the decoupling of short scale phenomena from physics at larger scales)   The wiki  whilst informative, doesn't actually say; if a group is not involved, then presumably some group like thing is; also what exactly is 'flowing' in the renormalisation group flow?


Is it possible to modify Sony PlayStation 1 games?  For example I'm planning to modify a soccer game called Winning Eleven 3. What I'm exactly trying to modify is player properties such as speed, shot power and so on.


My start menu icons look like this:    I'm using Windows 10 from Windows 7.  How can I make the normal icons appear (not just the shown generic blank icons)?


It would be nice if for each question only relevant reputation points appear, for both the question and the answers. Based on the question tags.  If a question is about Linux, we don't care about Windows reputation points. If a question is about networks, we don't care about database reputation points...


How to remove all traces of KDE installed

I have 2 computers with Ubuntu but on both I installed KDE to have another option for the users. Since Unity has come along very well, there has not been a need to use KDE for a while now. How can I delete all KDE related packages with one single sweep, freeing space and anything KDE related in Ubuntu, including overwriting the Logo of ubuntu when the PCs start or shutdown since after installing KDE the Kubuntu logo is the default one. How to revert back completely from all KDE stuff with a simple short command line or GUI tool.  NOTE - I ask this because it is very time consuming to start selecting, one by one, each package that relates to the KDE desktop environment, checking if it also relates to any GTK, checking dependencies for each, etc.. Deleting the package kubuntu-desktop does not remove every installed KDE package that was installed with it since this is a pseudo package that installs the rest of the real packages but does not uninstall them which makes me wonder why a package can install a whole bunch of other packages but not uninstall them with some added option to actually uninstall them not just the dummy package itself.


Why am I getting the message "You've failed too many recent review audits"?

Today I clicked on Review and saw the message below.     You've failed too many recent review audits - looks like you might need a break. Come back in in 7 days and try again.   Why does this type of message appear?  Is there any daily limit to viewing reviews on Stack Overflow?


Matching only "featured artist" in a set of filenames -- current regex too greedy

I'm writing a script in python to extract the name of the featured artist  from an mp3 filename and set the appropriate id3v2 tag of the file. The filenames are in 3 different formats:  Artist - Track ft. FeatArtist.mp3 Artist ft. FeatArtist - Track.mp3 Artist - Track (ft. FeatArtist).mp3   This is the regex that I wrote:  r'ft\. (.+)[.-)]'   Then I can use re.findall to get the contents of the group. But this is what I get:  In [40]: r = r'ft\. (.+)[.\-)]'  In [47]: re.findall(r, 'Artist - Track ft. FeatArtist.mp3') Out[47]: ['FeatArtist']  In [48]: re.findall(r, 'Artist ft. FeatArtist - Track.mp3') Out[48]: ['FeatArtist - Track']  In [49]: re.findall(r, 'Artist - Track (ft. FeatArtist).mp3') Out[49]: ['FeatArtist)']   My intended output is in all three cases precisely:  FeatArtist   The problem is that the regex is matching as much as it can - I want it to to stop as soon as it finds one of the characters in [.\-)]. How can I do this ?


If I say "I parked at a few streets distance from the stadium", should 'streets' have a possessive apostrophe? ("…a few streets' distance")  "…a few streets distance" can be rewritten as "…at the distance of a few streets". But 'streets' doesn't really own the distance. Now, I understand that 'possessive' is a misleading term. If I say "my city" I don't mean that I own it. But here, I can't see that the streets have any essential relationship with 'distance', they are just a measure.  So my thinking is that there is no apostrophe. I'd struggle to justify that conclusion, though...


Why didn't Fawkes rescue Dumbledore in the Half Blood Prince?

So has JKR ever mentioned, or is it indicated anywhere in canon why Fawkes did not come to save Dumbledore when he was confronted by Draco and the four other Death Eaters on the Astronomy Tower on that fateful night in Chapter 27 of the Half-Blood Prince?  There are several instances where Fawkes was timely in saving his master and Harry.  I know there's an out-of-universe answer to every question on books (Dumbledore had to die so that Harry can continue on this path alone, albeit aided by Ron and Hermione). I'm not looking for any of that please.  Was Dumbledore simply prepared to die that night?


I am not that proficient in Blender, and this has me baffled. I have it set to Cycles Render and I am using a single material that is Cycles also. I have a scene when the view port shading is set to rendered looks like this:   but this is what is rendered:    this is my outliner:  I had to add the outliner to the first image because you need 10 reputation points. really??  Any help would be appreciated.


Is there anywhere I can see my old school reputation score?

I'm curious as to what my old school reputation score would be on some Stack Exchange sites. Is there anywhere that I can see what my old school reputation score would be? For a period of time it looked like Area 51 had not updated and you could see everyone's reputations based off of the old rules, but that looks like it has  been fixed now.   Any ideas?


I'm trying to build a FM transmitter, but without sucess. The current schematic I'm using is this one:  The alternating current at the (+) of the op amp is the P2 output of my phone. V3 and V4 are 2 switching power supplies connected into the AC outlet. I am trying to calculate the inductor with this site:  The wire I'm using to build the inductor is from an UTP cable. The multimeter that I have is very simple, and I can't measure the inductance of the coil. I'm trying to tune this on the radio of my other phone, and can't get it to work. I'm building this on a breadboard. I would appreciate it if someone could help me.


Recently I've been into the idea of hooking up a Bluetooth receiver to my car stereo via my car radio's aux input. I got a Bluetooth receiver module from an old Bluetooth speaker that I had laying around. I disconnected to speaker and, not surprisingly, it was a mono speaker output on the circuit board. I took an aux cable, cut it open, wrapped the left and right together and soldered it to the positive output and soldered the ground wire to the negative output on the board. I plugged it into my car, connected to the module with my iPhone and played Spotify... It worked, but audio only came through the left side of the stereo car system.  My question is: Is there anyway to play the mono sound through both stereo speakers?


how to remove words from a dictionary in dataframe

I am trying to remove certain words from a dataframe column and failing miserably...  Some of my sample data:      Stock_Name Vanguard US Government Bond Index GBP Inc (Hedged) Vanguard US Government Bond Index GBP Acc (Hedged) Vanguard US Government Bond Index GBP Inc Vanguard US Government Bond Index USD Acc   The dictionary:      replace_values = {         r'\bAcc\b': "",         r'\bInc\b': "",         r'\b(Hedged)\b': "",         r'\bGBP\b': "",         r'\bUSD\b': "" }    df["Stock_Name"] = df["Stock_Name"].replace(replace_values,regex=True)    The output I am getting:  Vanguard US Government Bond Index   () Vanguard US Government Bond Index   () Vanguard US Government Bond Index   Vanguard US Government Bond Index     for some reason the parentheses are being omitted. I have tried adding '()' to my replace values dict but it doesn't seem to do anything.


I want to change the section labels so that, instead of writing something like '1 Section', I get 'Section 1'.  I want to keep the numbering.  How can this be done in Latex?  \renewcommand? section*{}?    Something else?


Suspend broken on Ubuntu 16.04 LTS, Dell XPS 9350

Since I upgraded from Ubuntu 15.10 to Ubuntu 16.04 LTS on my Dell XPS 9350, suspend is broken. When closing my lid the laptop will suspend, but resuming fails and it reboots. I tried pm-suspend and tried resuming, resuming failed and the laptop rebooted. I got the following errors when I got back into Ubuntu. The odd thing in my opinion is that it claims the kernel is not an official ubuntu package. Either way my Linux knowledge is not sufficient to know what's going wrong here.      EDIT: I just tried installing kernel 4.4.8 which should fix some things, but it did not fix this problem. By now I also tried 4.4.9 and 4.6 RC7. None of them fixed it for me.


Can I use a 12v 20A DC switch for a 24v 10A DC load?

– Schematic created using   I have a toggle switch that is rated for 12v 20A (240 Watts) and I have a load from a battery that I want to turn on or off with this switch. The battery is 24v 10A (240 Watts). Everything is DC  Can I use this 12v switch with a 24v load if the watts are the same? If not why?


I am trying to draw lines around a number of nodes. I very much like the definition of \convexpath definition given , but it is not working well on my setup (MacTex 2014 with all available updates).   I tried to compile , but what I get is the following, which is clearly not what I should be getting. Any ideas would be much appreciated.


Variable undefined after function is fired - why?

I have some function linked into another and I want to a) do (remove a class) something to the result of one of those functions and I want to b) do something else (add a class) with the very same result when the click-event - that fires the functions also the first time - is fired the next time. While a) works nicely, I do get an error for b) Uncaught ReferenceError: randActivity is not defined because the result that I have in a) is now not set/defined anymore. I don't get why. Can sobody please help me on that code         window.onload = function() {         var items = Array("pushup", "pullup", "run");           function rand(items) {             var randActivity = items[items.length * Math.random() | 0];             document.getElementById(randActivity).classList.remove("not");         }           var runden = 0;         var display = document.querySelector('#displayTimer'),             timer = new CountDownTimer(5),             timeObj = CountDownTimer.parse(5);         format(timeObj.minutes, timeObj.seconds);         timer.onTick(format);           document.querySelector('#startTimer').addEventListener('click', function() {             if (runden != 0) {                 console.log(randActivity); // this is the spot where the error happens.                  document.getElementById(randActivity).addClass("not");             }             timer.start();         });           function format(minutes, seconds) {             minutes = minutes < 10 ? "0" + minutes : minutes;             seconds = seconds < 10 ? "0" + seconds : seconds;             display.textContent = minutes + ':' + seconds;             var zeitErgebnis = seconds;             if (zeitErgebnis == 00) {                 runden++;                 rand(items);                 display = document.querySelector('#displayTimer'),                     timer = new CountDownTimer(5),                     timeObj = CountDownTimer.parse(5);                 format(timeObj.minutes, timeObj.seconds);                 timer.onTick(format);             }         }     };  The error happens in the addevent if the function is fired NOT for the first time. But shouldn't be the variable of randActivity then have the result that it has within the function of format()? Why not?


How many cpu sockets does Windows 10 support?

I would like to build a new computer (it's been 7 years since the last one). Does Windows 10 support more than one ?


How to best encapsulate monetary values in a database

I am working on a multi-currency application. For the purpose of simplifying this question, we will not be considering currency conversion (hence I have deliberately left AsAt : datetime out of the equation). In a number of places I need to store monetary values (e.g. 1.23 USD). I understand that I need to store both the amount (1.23), and the currency (CurrencyID with FK to Currency table having ISOAlpha3Code = USD). My question is, how should I best encapsulate and isolate these two data from the other columns in the table (TableX) to which the monetary value relates?  As I see it, I have three options:   I store two columns in TableX, one being the Amount (numeric(p,s)) and one being the CurrencyID (FK). I add an XOR check constraint on the two columns to TableX. (DBMS dependent) I create a CLR UDT (or equivalent) representing Currency, storing both Amount and CurrencyID. I store one Currency type column on TableX containing the monetary value. I create a MonetaryAmount table with three columns: MonetaryAmountID (surrogate PK), CurrencyID (FK), and Amount. I add MonetaryAmountID (FK) to TableX.   I dislike #1 because I have used this pattern before and nobody has understood that the two data are part of the one complex datum; also, it's not normalized. I dislike #2 because it breaks 1NF, it is DBMS specific, and it will likely be difficult/expensive to enforce referential integrity on Currency. I'm rather ambivalent towards #3 - it feels over-engineered and will probably be computationally expensive, but it is correctly normalized.  #3 also has the added complexity of whether to place a unique constraint on the (CurrencyID, Amount) combination, thereby making it an ad-hoc reference table and better normalizing it. I believe it would be best not to do this, as whilst MonetaryAmounts may correlate, they are distinct in nature.  Any experience you can share (or alternatives you can suggest) would be appreciated. I would especially like to hear from genuine database architectural gurus.


What does "Awaiting SE Preliminary Decision" mean for IEEE transactions journal?

I have a manuscript with IEEE Transactions on Control Systems Technology under peer review from early Jan 2020. Today, there has been a status update on the journal's ScholarOne online portal which says "Awaiting SE Preliminary Decision".  What does this mean?   What does the 'SE' stand for? Why is the decision to be made by the SE classified as "preliminary"? Will there by further non-preliminary decisions made at the editorial office?


How does Gifmaker.org remove white halo on transparent GIFs?

When I try to export with Photoshop or use other online GIF makers, they always end up with the ugly white halo. What makes Gifmaker.org so different, and how can I replicate it in Photoshop or Adobe Effects?


I am flying from Chicago(USA) to New Delhi(INDIA) via London Heathrow Airport(LHR). Actually the route is the following -   Chicago --> London Heathrow --> Munich --> New Delhi.  The layover at LHR and at Munich are of 2 hours each. I am worried if I need to get a transit visa for the flight to Munich. I have browsed through other questions related to this, but I just need an assuring confirmation that I won't need a transit visa.  Edit- I hold an Indian passport and study at the USA with F1 visa.


for $f\in L^1[0,2\pi]$ define $$\hat{f}(n)=\int_{0}^{2\pi} f(t)e^{-int} dt$$ for $n\in\mathbb{Z}$, $X$ is a closed linear subspace of $L^1[0,2\pi]$ such that $\sum_{n} |\hat{f}(n)|<\infty$ for each $f\in X$, we need to show that there is $M<\infty$ such that  $\sum_{n} |\hat{f}(n)|\le M\int_{0}^{2\pi}|f(t)|dt$ for each $f\in X$  please tell me how to solve this one, I have no clue.


Is 70mm really necessary? Wouldn't it work with 35mm too?

So I just came back from Dunkirk, seen in IMAX, 70mm version.  I was digging around the internet with my question but only found religious answers (it's just better, can't describe it, you must see it), rather than technical.  So I just considered these statements, which are hopefully correct:   IMAX is screening films in 2K resolution According to IMAX, 35mm film has a digital equivalent of 6000 lines of horizontal resolution (6K), while 70mm film has the equivalent of 18,000 lines of digital resolution (more like 12,000 in reality).   => 35mm seems to be more than enough for IMAX screen, why 70mm then?  I'm familiar with the DSLR world. Full frame cameras are better than APS-C, because the sensor captures more light, the camera performs better especially in bad lighting conditions. So for example you don't have to use so high ISO and have less noise and stuff like that. I did some simple tests (nothing exact, just going out with both FX and APS-C camera) and I would say that with good lighting (like on a sunny day), the difference in output photos is almost non-existent.   Back to my question. My thoughts are that:   70mm is more about being commercially interesting. The main difference in IMAX is the aspect ratio Probably it gives the director (cameraman) some more space on what to do as the sensor is bigger and therefore captures more light. Some shots would probably look worst on 35mm.   Still not sure about: If they did shoot it on 35mm (even crop it to keep the IMAX aspect ratio), then screen it in IMAX on the same screen, would it look that much different?  edit: The question  is different. It just asks what 70mm is. My question is more about whether 70mm makes any difference in comparison to 35mm given screen sizes and the fact that 35mm is already more than enough to capture resolutions needed for big screens such as IMAX.


What's the difference between accessing struct members by pointer as opposed to by reference?

In "The C++ Programming Language (4th Edition)" Section 2.3.1, Stroustrup shows 3 different ways to access members of a struct:  void f(Vector v, Vector& rv, Vector* pv) {     int i1 = v.sz;    // access through name     int i2 = rv.sz;   // access through reference     int i4 = pv->sz;  // access through pointer }    I understand that for the first one, v is passed-by-value, so a copy of the first argument is put on the function's stack and the value of its size sz is stored inside of i1. In the second example, rv is a reference to the struct passed as the second argument. Because it is a reference, we can access the value referred to by rv without a * prefix.   I'm not too sure I understand what's going on with i4, and why someone would pick the third example over the second (or vice-versa).


Python - newline if variable is in print function, need fix

I have one problem with print in Python, I am starting to learn Python, but when I want to print variables in print function, it looks like that after one variable it adds newline to the outcome: print(game_name + " | " + rating)  I am making a game database with my own ratings on the games but if it prints the game and the rating there is like one empty line belpw the game_name and rating is written, how can I delete that empty newline? I am very new to this, so please don't be mean...


Real numbers as a $\mathbb{Q}$-linear space

Let's consider the real numbers as a $\mathbb{Q}$-linear space and denote it by $\mathbb{R}_{\mathbb{Q}}$. It was proved  that $\dim  \mathbb{R}_{\mathbb{Q}} > \aleph_0$. I suspect that the dimension is actually $\mathfrak c$. But how could we prove it's really $\mathfrak c$ ?


What's the correct one: "one did show up" or "one showed up"?

Is there any difference between these two sentences? Is one of them wrong?   Even if a ship did show up Even if a ship showed up


Does there exists a continuous surjection from $\mathbb{R}$ to $\mathbb{R}^2$?

I constructed a bijection by using decimal expansions of two real numbers and taking numbers 1 by 1 consecutively. (It took me hours to come up with this). I remember someone saying appealing to some sort of expansion is the only way to do this, and I think this type of method can never be continuous. Is there anyway to prove that no such function exists?


I have one object:  Object { name: " ", email: " " }   and another:   Object { name: Array[x], email: Array[y]}   and I want union like:  Object { name: {" ", Array[x]}, email: {" ", Array[y]} }


How to code values for males when they're only meaningful for females?

I'm building a predictive model for a medical condition that happens in both men and women. Physicians have reported that in some cases for women, their menstrual history seems to be a risk factor, though epidemiologists haven't been able to verify this claim. My data includes information about female subjects' menstrual history. My goal is to build a logistic regression model that determines the probability of the existence of this condition.  Here's my problem: I'd like to build a model that includes gender and includes menstrual history questions for female subjects, but how do I assign values for male subjects for things like "number of months since last pregnancy"?  Is there a general method to deal with this kind of problem?


Does using a SSD as a sawp damage the component faster?

I know that SSDs have a shorter write lifespan, even tho many say it will last more that the average user would use, I think that using it as virtual memory would burn it out way faster than the usual read/writes of a common user that do not work with audio/visual for example. Is there any definite answer for this? Would it burn that section faster? Is there anything one could do to align the sections so that an minimum amount of cells are damaged at once?


Can you travel to the UK with an EU national Identity card that is only valid for another week upon return?

For international trips I have a passport, for EU journeys I use my national identity card. Simply because its format is more convenient, since it fits in my wallet.  On my next trip to the UK my national identity card will only be valid for only one week when I return.  I am aware of validity issues on passports (e.g. your passport needs to be at least valid for more then 6 months when traveling to the US), what are the regulations regarding national identity cards in the EU? Can I use it to travel within the EU until the last day of its validity?


Can I still download OS X Mavericks for Free?

I never upgraded to Mountain Lion or Mavericks and now that Yosemite has arrived  I thought of upgrading but I find that some of my software will not work with it. So I would like to upgrade to Mavericks for now. Is it still possible to get the free upgrade? I no longer see it listed in the Mac App Store.


Why does pressing a transform hotkey not display the axes on the selected object?

I open Blender 2.80 (official release, not a beta or RC) and get the new scene with the usual 3 objects present (camera, light and cube). I select the cube, press 't' for the tools menu and click on the Move tool. The usual 3 axis glyph appears at the cube's origin as expected. But if I use the hotkey 'g' to activate the move transform instead of selecting the tool from the menu with the mouse this glyph does not appear. The exact same problem exists if I use the a hotkey for rotate or scale as well. Why? Is there some clickable checkbox setting hidden somewhere that could have disabled this?


how to calculate voltage between two points

how to calculate voltage between A and B?


I'm trying to understand solar panel Maximum Power Point Tracking theory and how it is done practically for charging battery banks.  I think I understand MPPT in a general sense: the solar panel has VI curves which define a specific load in which you will extract the most power. These curves change with environment conditions like light levels, temperature, etc, so the tracking algorithm tries to dynamically find the best load value. It's usually not practical to just change the actual end load that we want to power (and often can't), so we use a switch mode power supply to adjust the output voltage, changing the output current. To balance Pout = Pin (assuming ideal switcher), the panel's current draw changes, and this is how we adjust the operating point on the panel's VI curves.  So my question is this: We are changing the output voltage to get the maximum power, but don't batteries typically need a specific voltage to charge them efficiently? Is it better to shoot for MPP of the solar panel or shoot for optimal charging conditions for the battery?


Building Expression Tree for string.Contains

I'm struggling to build an expression tree so I can dynamically do filtering on some data.  I have come up with this, but it fails at the var lambda = line  foreach (var rule in request.Where.Rules) {     var parameterExpression = Expression.Parameter(typeof(string), rule.Field);     var left = Expression.Call(parameterExpression, typeof(string).GetMethod("ToLower", Type.EmptyTypes));     var right = Expression.Constant(rule.Data.ToLower());     var method = typeof(string).GetMethod("Contains", new [] { typeof(string) });     var call = Expression.Call(left, method, right);     var lambda = Expression.Lambda<Func<T, bool>>(call, parameterExpression);     query = query.Where(lambda); }   The var rule has a Field (ex "Name") which I want to compare with the text in rule.Data (ex 'tom').  So if T.Name.Contains("tom"); I want the query to include the record, otherwise, not.  The var query is of type IQueryable<T>  EDIT: Finally got it working with this code:  foreach (var rule in request.Where.Rules) {     var parameter = Expression.Parameter(typeof(T), "x");     var property = Expression.Property(parameter, rule.Field);     var value = Expression.Constant(rule.Data);     var type = value.Type;      var containsmethod = type.GetMethod("Contains", new[] { typeof(string) });     var call = Expression.Call(property, containsmethod, value);     var lambda = Expression.Lambda<Func<T, bool>>(call, parameter);     query = query.Where(lambda); }


Question Concerning Solutions of a Congruence that is Unique Modulo m

I have been working through exercises in a book on polynomials. There is a section in the first chapter on some basic number theory.  I am having trouble completing one of the exercises. Part (e.) of the exercises goes like this : "We say that the solution of a congruence $ax \equiv b ( \mod m)$ is unique modulo $m$, or simply, unique, if the difference between any two solutions is divisible by $m$. In other words, the requirement is that $au \equiv av \equiv b (\mod m)$ implies $u \equiv v (\mod m)$. Show that the solution of the congruence is unique if and only if $\text{gcd}(a,m) = 1$." Here a solution to the congruence is some $x \in \mathbb{Z}$ s.t. $ax \equiv b(\mod m)$ is true. I suspect $u$ and $v$ are two arbitrarily chosen solutions. I think I am able to prove the forward implication but not the backwards one. We see : \begin{equation} au \equiv av \equiv b ( \mod m) \Rightarrow m | (au - b) \text{ and } m|(av-b) \end{equation} Where $x|y$ means that $y$ is divisible by $x$. The above implies : \begin{align} & \Rightarrow m | \left[ (au - b) - (av - b) \right]   \\\\ & \Rightarrow m | \left[ (au - av) + (b - b ) \right]  \\\\ & \Rightarrow m | (au - av)                            \\\\ & \Rightarrow au \equiv av ( \mod m) \end{align} So this implies : \begin{align} \Rightarrow m | (au - av) \Rightarrow m | a(u-v) \end{align} We then see : \begin{equation} \text{gcd}(a,m) = 1 \text{ and } m | a(u-v) \Rightarrow m | (u-v) \text{ and } m \not | a \end{equation} Where $m \not | a$ means that $a$ is not divisible by $m$. So in this case : \begin{equation} u \equiv v ( \mod m ) \; \checkmark \end{equation} So here I've shown that : \begin{equation} \text{gcd}(a,m) = 1 \text{ and } au \equiv av \equiv b (\mod m) \Rightarrow u \equiv v (\mod m) \end{equation} But I haven't shown that : \begin{equation} \text{gcd}(a,m) \neq 1 \text{ and } au \equiv av \equiv b (\mod m) \Rightarrow u \not \equiv v (\mod m) \end{equation} Can anyone help me with how to prove the converse ?


when there is a new invention, there is a new name for original object, what is this called?

IS there a term or lingusitic device for a name change of a noun / object that has had to change its name because of a new development. For example the invention of the electric guitar, meant the humble guitar became known as an acoustic guitar? Thank you.


Check it List of objects contains string

here is my function  private static List<Types> getShiftTypes() {      List<Types> types = new ArrayList<>();      for (String shift : shifts_arr_t) {          if (!types.contains(shift)) {              types.add(new Types(shift));         }      }      return types; }   Types:  public class Types  { String type; int count;  public Types(String type) {          this.type = type;  }  @Override public boolean equals(Object object) {     boolean sameSame = false;      if (object != null && object instanceof Types)     {         sameSame = this.type == ((Types) object).type;     }      return sameSame; } }   But the compare override is not working. Can you please help me with that?


Many years ago I took a philosophy class that covered Descartes.  The teacher logically explained to us the "I think Therefore I am" over the course of a week.  He also said that it was one of the very few things that you could prove.  He made it seem like there were other things that could also be proven at the most basic of levels, but he never talked about them.  He then went on to some other topic I think it was about Leibnitz and Monads.  My question is, are there other ideas or things that are provable like the "I think therefore I am" and if so, what are they?  I'm also aware from reading Wikipedia that the "I think therefore I am" can be generalized even further.  But are there any fundamental ideas like it that can also be proven?  I don't know if this helps, but apparently this teacher is one of the best in understanding and interpreting the philosophy of Immanuel Kant.  So it's possible that some of those provable ideas he was referring to might be from Kant.  edit: I want a list of proved things in bullet format preferably. From the other similar questions I was able to get: 1.cogito ergo sum 2.axioms of logic  Are there anymore?


This question is a question in my textbook, and I cannot stop thinking about it. The question: Is $\pi$ even or odd? I don't know if even or odd is defined for decimals or for irrational numbers, or if it is, how to find whether $\pi$ is even or odd. Can somebody help?


Searching for a conjecture that is true until the 127 power of n.

I am searching for a mathematical conjecture that is true until something like n = 117, or n = 127, or a number close.  It is an equality, a formula implying calcultations to the power of n, IIRC.  What is the name of this conjecture ?     Why do I search for this formula ?:  I had read an article a few years ago that was discussing about experiments around the validation of a theory in Science, namely in Physics.  The example of this conjecture was given so as to convince that you can choose to repeat an experiment with different parameters a certain number of time, ultimately in the end, it does not give the entire certainty a physical theory is true: it just happens we still haven't found any outlier measurement that contracdicts the physical theory.  As a matter of fact, we can test this mathematical conjecture for the first 127 integers, which is a bunch of times, and believe it is always true, whereas it is false for all n.   I would like the name of it so as to be able to name it / source it in discussion.   Does it ring any bell for you ?


Change a global variable through a function: UnboundLocalError

#!/usr/bin/python  import rospy import serial import time from std_msgs.msg import String  ser = serial.Serial('/dev/ttyUSB0', 9600) print (ser.name) time.sleep(2)  #=========================================================== # An o y ine i kateuthynsi kinisis (mikos deksamenis) # Gia kinisi se eutheia x_d = 0 # mm y_d = 2000 thita_d = 0 # moires i rads #===========================================================  camera = [0, 0, 0] error = [0, 0, 0] data = [0, 0, 0] print(data) def camera_feedback():     # dedomena apo camera-RPi-seiriaka apo allon komvo mallon...     #camera = [x_c, y_c, thita_c]     #x_c = camera[0]                    #isws mpei kwdikas gia na diavazei apo tin     camera[0] = 0     #y_c = camera[1]                    #seiriaki tu RPi (opws to serial_connection())     camera[1] = camera[1] + 250     #thita_c = camera[2]         camera[2] = 0     print(camera)  def error_calculation():     error[0] = x_d - camera[0]     error[1] = y_d - camera[1]     error[2] = thita_d - camera[2]     print(error)  def controller_equations():     # edw mpenun oi eksiswseis tu michali     # kapws pernei to error kai alla dedomena kai dinei w, A, thita_mesi gia na stalun ston PIC     if error != [0, 0, 0]:         print(error)         print(data)         data[0] = 8         data[1] = 8         data[2] = 0     else:         data = [0, 0, 0]     print('kokos')     #data = [w, A, thita_mesi]     #na dw ti format dexete o kwdikas tu PIC  def serial_connection():     rospy.init_node('serial_connection', anonymous = True)     rate = rospy.Rate(10) #isws na min xreiazetai      if not rospy.is_shutdown():          ##data1 = bytearray(data)         ##rdata = bytearray()         ##rdata.extend(data1[0:2])         ##rdata.extend(data1[2:5])         ##vect = list(rdata)         ##print(vect)          if ser.isOpen():             print ("Port Open")             for i in range(1):                 #ser.write(b'5')                 #ser.write(chr(5)) auto stelnei kwdikopoiimenus xaraktires, ox$                 #ser.write(5)                 ser.write(bytes(data) + '\n')                 #print ('Hola!')                 #ser.write("Hola!\n")                 time.sleep(1)                 rate.sleep()  if __name__ == '__main__':     try:         while not rospy.is_shutdown():             camera_feedback()             error_calculation()             controller_equations()             serial_connection()         ser.close()     except rospy.ROSInterruptException:         pass   I run the code above and I get the error: UnboundLocalError: local variable 'data' referenced before assignment  I want to change the value of the global variable data through the function controller_equations(). I did the same with the variable camera in the function camera_feedback() without any error. I searched other posts for an answer but all of them say that is not possible to chance a global variable through a function. Any possible solution or a tip will be appreciated.  I am new in Python and I use Ubuntu 16.04 and Python 2.7.   Thanks in advance.


Would I delay flights, when not showing up for part of the journey?

This is a hypothetical question.  Say you book a flight from A through B to C. For some reason or another, you choose not to board the last part of my trip. Would this create problems for other passengers?  When a checked in traveller does not show up for a flight, that flight is actually delayed – at least if he/she has baggage checked in. If he/she doesn't show up within a reasonable time, the crew will start off-loading the baggage, delaying the flight even further. In my experience, this process takes approximately 20 minutes (which may be very frustrating for other travellers, whom may have planes to catch at the next airport).  So, to recap:   If I don't show up for one part of the journey, will that delay those flights? What if my luggage is short checked to point B (for example,    when they need to be taken through customs) and you don't check them  back in? What if I only bring carry-on luggage?    There are some related questions below, but they focus on whether or not you as a traveller may face problems, whereas I am more interested in what problems it will cause for the airlines and other travellers.


Why is $f\in C_{\infty}=\{f\in C(\mathbb{R})\mid \lim_{R\to\infty} \sup_{∣∣x∣∣>R} ∣f(x)∣=0\}$

Today in my mathematical quantum theory lecture our professor told us without any explanation, that if $f\in L^1(\mathbb{R}) \cap C^1(\mathbb{R})$ and $f'\in L^1(\mathbb{R})$ it follows that $f\in C_{\infty}=\{f\in C(\mathbb{R})\mid \lim_{R\to\infty} \sup_{∣∣x∣∣>R} ∣f(x)∣=0\}$, where we consider $R$ as a radius. Is there an easy way to see that? For me it is not quite obvious. What informations do I get from the conditions that tell me, that this kind of functions are vanishing at infinity?


I have 2 PCs with Ubuntu 12.04 and I have had problems with syncronization of the files. When I modify a file or when I try to connect it my UbuntuOne don't make the synchronism and show me the message: (auth failed (AUTH_FAILED)). How do I do to fix it?  Thanks, Vinícius.


$x \in \mathbb R^d$, $B$(closed)$ \subseteq \mathbb R^d$. Where $\mathbb R^d$ is an inner product space. Proof help

$x \in \mathbb R^d$, $B$(closed)$ \subseteq \mathbb R^d$. Where $\mathbb R^d$ is an inner product space.  Show that there exists a point $b_0 \in B$ such that $d(x,B) = \|x - b_0\|$  My attempt:  $d(x,B) \le \|x - b\|$ for some $b \in B$ because $d(x,B) = \inf\{\|x-b\|\}$  For a point $b_0 \in B$(closed), does this imply that we can find a point $b_0$ such that it is equal to $\inf\{\|x-b\|\}$?   I feel like I can draw a picture to show this but I can't figure out the right logic to prove it. Any help is greatly appreciated.


What is the difference between a symbolic link and a hard link?

Recently I was asked this during a job interview. I was honest and said I knew how a symbolic link behaves and how to create one, but do not understand the use of a hard link and how it differs from a symbolic one.


avast disappear and doesn't re-install/uninstall/repair

It happened this morning: Avast Antivirus Free just disappeared from tray icon ?!  I checked the installation directories, and everything is in there, but the antivirus didn't started.  I tried to repair/uninstall, through Control Panel, but it show me an error message.  I tried to use Avast Clear, from here , but it stuck in the first screen.  I tried to use it again, in Safe Mode, but it stuck again.  So, in safe mode, I removed "all" avast entryies in register, restarted the computer and installed Avira. (But I prefer Avast)  I am using: Windows 8.1 Pro 64bit.  The last Windows Update is: Windows Defender KB2267602, but it shows an error, and I'm think this messed up with Avast.  Does anyone know what could be happened ?


Can you do a t-test or ANOVA between 2 or 3 groups respectively if one of those groups has a sample size of 2? Are the results interpretable in the same way as with larger sample sizes(n=4,5,6?). If you can provide any references to read more about very small sample size statistics, that would be helpful.


Why do objects of type B (subclass of A) in a vector of type A behave as type A?

Thanks for taking the time to look at this question. I was hoping someone could explain a behavior too me of the classes below and maybe a way to fix it. I believe there may be a simple solution to this but I haven't been able to find a solution with the Google machine so far. Consider the code below: void overloadExample() {   class A   {   private:   public:     A(/* args */){};     ~A(){};     int typeone = 1;   };       class B: public A   {   private:   public:     B(/* args */){};     ~B(){};     int typetwo = 2;   };    class foo   {   private:     /* data */   public:     foo(/* args */){};     ~foo(){};     void printer(A atype){std::cout<<atype.typeone<<std::endl;};     void printer(B btype){std::cout<<btype.typetwo<<std::endl;};   };      std::vector<A*> test;   A* atest = new A();   B* btest = new B();   test.push_back(atest);   test.push_back(btest);   foo ptest;   for (size_t i = 0; i < 2; i++)   {     ptest.printer(*(test.at(i)));   }   delete atest;   delete btest; }  output is: 1 1  but I am hoping to somehow get 1 2  My question is why does the object of type B behave as type A? Is there a way to make it call the overloaded function intended for type B as in foo? Update: This question was closed as a repeat of an object slicing question but there is more too the problem which I believe can be solved by


Why position: absolute; and bottom: 0; not being at body's bottom?

update: I know adding a position: relative; to body will make the element be at body's bottom, I just didn't find the description of when not found the non-static parent, what the position would be related to. So I don't think this question is duplicated to . Thanks to @Ben Kolya Mansley  ====  I am writing a component, and met a problem. I set an element position absolute and bottom 0, and append it to document.body (the body height is more than a screen's height), but it is not at body's bottom but viewport's bottom. Why is it so wired?   I read the mdn of position and bottom. It says element with position absolute will look for a non-static positioned parent, if not found, it will be relative to body.   <!DOCTYPE html>         <meta charset="utf-8" />     <meta http-equiv="X-UA-Compatible" content="IE=edge">     <title>Page Title</title>     <meta name="viewport" content="width=device-width, initial-scale=1">
this is bar


I'm interested with this table of contents  In this question there is the answer but as i'm not good in latex i don't know how to make a tex files wich works     please help me   Thank you


"I want you to know how much your effort, time, and work {are/is} appreciated."

What kind of verb we should use after some uncountable nouns separated by commas as the subject of our sentence? In the following example do we need is or are?     I want you to know how much your effort, time, and work are/is appreciated.   I want you to know how much your effort, time, and work are/is appreciated.


Is it possible to open an Access 2010 database file without using Wine or VirtualBox?

I have a .accdb file created with Microsoft Office 2010 and I want to know if it is possible to open it with some native Ubuntu application like LibreOffice or OpenOffice, I know LibreOffice has LibreOffice Base but I can't figure out how to open or if it's even possible to open a .accdb file.  Is there any way I can open a .accdb file without Wine or VirtualBox?


Small snap loop devices visible in gnome-disk-utility OR what is the function of snap ubuntu-core

I just realized using gnome-disk-utility (3.18.3.1) that my 16.04 installation is featuring several small loop devices.  In detail:   78 MB Loop Device (/var/lib/snapd/sn_ntu-core_352.snap -> /dev/loop0) 76 MB Loop Device (/var/lib/snapd/sn_ntu-core_216.snap -> /dev/loop1) 79 MB Loop Device (/var/lib/snapd/sn_ntu-core_423.snap -> /dev/loop2) 705 KB Loop Device (/var/lib/snapd/snaps/tpad_12.snap -> /dev/loop3) 684 KB Loop Device (/var/lib/snapd/snaps/tpad_11.snap -> /dev/loop5) 705 KB Loop Device (/var/lib/snapd/snaps/tpad_13.snap -> /dev/loop6)   Image showing gnome-disk-utility    My questions are as follows:   What are those loop devices used for? Is that an expected behaviour in 16.04? Can  I remove them? And if so - how (just by unmounting)? Is there any risk in removing the 2 installed snaps mentioned below (tpad and ubuntu-core)   UPDATE  Installed snaps  According to snap list I do have   tpad (1.8.1) ubuntu-core (16.04.1)   installed. I remember I did tinker with snaps for a short time when  I realized this option - but am pretty unsure if  I  installed those 2 snaps - or if they are pre-/auto-installed.  tpad is a Terminal text editor with GUI-like user interface  I  did install manually, as  I don't use it  I removed it now via sudo snap remove tpad. As a result the 2 loop devices pointing to tpad are gone in gnome-disk-utility.  So - at the current point  I am still having 1 snap installed called ubuntu-core and I don't know what it is used for. The summary of this particular snap is   The ubuntu-core OS snap


when I click various times on "edit" next to my comment, the editor appears multiple times (the second time there are two editors in the first box and another one at the bottom and the third time there are three editors in the first box etc.)  See this screenshot:


Imgur is blocked by my internet provider. Is there another way to view pictures in posts?

Since the first time I joined SE, I liked the site, but I couldn't see any of the pictures in posts because my Internet provider blocks Imgur as a restricted area.   Is there another way to see the pictures?


Schengen visa refused "an alert has been issued in the Shengen information system refuse entry by a member state"

I applied for a Schengen tourist visa through the Italian consulate in Karachi in July 2019 but got a refusal letter which says an alert has been issued in the Schengen info system for the purpose of refusing entry by a member state.  I have the right to appeal within 60 days.  I previously applied in 2018 for a Schengen tourist via the Netherlands consulate but refused under common reasons justification purpose of stay and no strong ties. My recent application was strong enough but I got this unusual refusal reason. I dont understand what to do please help me.


Check if a file already exists in a particular folder

I want, before uploading a file in image folder, to check if the file in the folder already exists or not. If the file already exists it should show a message.  from flask import Flask, render_template, request from werkzeug import secure_filename  UPLOAD_FOLDER = '/path/to/the/uploads' ALLOWED_EXTENSIONS = set(['txt', 'pdf', 'png', 'jpg', 'jpeg', 'GIF'])  app = Flask(__name__) app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER import os, os.path   APP_ROOT = os.path.dirname(os.path.abspath(__file__)) UPLOAD_FOLD = '/python/image/' UPLOAD_FOLDER = os.path.join(APP_ROOT, UPLOAD_FOLD) app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER    @app.route('/upload') def load_file(): return render_template('upload.html')  @app.route('/uploader', methods = ['GET', 'POST']) def upload_file(): if request.method == 'POST':   f = request.files['file']      f.save(os.path.join(app.config['UPLOAD_FOLDER'],secure_filename(f.filename)))   return 'file uploaded successfully'  if __name__ == '__main__': app.run(debug = True)


Comparing strings in java that are already in the memory pool

So I've read that if you write this:  String a="foo";  String b="foo";  System.out.println(a==b);   it will print "true", because the first implementation checks the memory pool looking for "foo", it cant find it so it creates a new object and puts foo in the memory pool, then every other string will be pointing to the same object.  and if you write:  String a="foo";  String b=new String("foo");  System.out.println(a==b);   it will print "false", because you force a creation of a new object for b so it wont take it from the pool.   my question is if you write this:  String a=new String("foo");  String b="foo";  System.out.println(a==b);   why does it still print "false" ? I mean "a" creates a new object and doesn't look in the memory pool, but b should look in the memory pool and find the object "a" created and point to it. what am I missing here?  thank you.


How replace a word in a text file using a .bat file?

I am new to the bat scripting, so I'm planning to change a word in a text file called "sampleFile.txt"      Can anyone help me? Thankx :)


Design Nuances: Can they add value to any design, or are they simply a personal taste decision?

Update  Since asking this question, I've come to a better understanding of how question scope should be defined (more precisely than this question's original version), so I'll better define the scope herein.     Nuances in Interface Design  Somewhere in my question, , a user expressed vivid appreciation for the nuances of graphic design, expressing their importance. I didn't agree so much with the importance of such subtle features in graphic design, so I posed this question.  Are the nuances of graphic design important?  In user interface design, I've heard artists stress that the "smaller things" are actually of equal importance with the "general features", or at least, very important.     General Definition of Nuances  The smaller things are the subtle features, the nuances of an interface's design. The effects of light touch, going unnoticed without close inspection but contributing to the page in a collective way.  I personally love to pay attention to finer detail; I think subtle detail collectively makes a design unique and adds finesse. But that doesn't necessarily mean that it's a very important aspect of interface design.    Example  Facebook:    While Facebook's design is beautiful, crisp, and, in my personal opinion, good-looking, all of the visual features that I see are very obvious, each serving a specific purpose. I don't see anything that goes unnoticed at the first glance.   Every feature seems to be an important aspect of the page's layout and functionality, not a supporting detail that adds unnoticed finesse to the design.  Twitter:    Twitter, on the other hand, shows a handful of interface design nuances. Subtle outlines, the subtlety through which the twitter icon is engraved (top, center), faint clouds in the background, as well as a few other non-functional, decorative features of subtlety in mobile versions of the interface.  Many of the features seem to provide subtle, decorative value to the interface's design without directly contributing to the its functionality in an obvious way.   The (Updated) Question is:  Can these nuances add value to any design, or are they simply a personal taste decision?


Proving that an irrational number exists near every rational number

Show that arbitrarly close to any rational number there is a real (non-rational) number. In other words, show that to each real $\varepsilon>0$ and each rational $r\in\mathbb Q$ there exists $x\in\mathbb R\setminus\mathbb Q$ with $\left|x-r\right|\lt\varepsilon  $   No idea how to prove this one. Perhaps I can define some sort of sequence and show it converges...?


What do you call an interfix that has semantic meaning?

At university I was introduced to various affixes; prefix, suffix, interfix.  The latter, I was told, could be created by putting an adjective in the middle of a word, thus interrupting it; abso-bloody-lutely or done-diddely-one (as used by The Simpsons' character Ned Flanders). It is highly likely this kind of 'interruption' is mostly used in spoken language.  However, according to Wikipedia, Glottopedia, and other sites, an interfix has no intrinsic meaning and is phonological, used to link two morphemes; speed-o-meter, for instance.  What I would like to know is what to call an "interfix" that may have meaning, and/or is used as a form of exaggeration. Is it still considered an interfix?


Is there a T0 space with a subset A such that (A')' is not a subset of A'?

By $A'$ I mean the set of limit points of $A$, so $A''$ is the set of limit points of $A'$.  There is no T1 space with such a subset. Proof:  Suppose $X$ is a T1 space and let $A \subset X$. Let $x \in A''$ and $U$ be an open neighborhood of $x$. By definition, there exists $y \in U \cap (A' \setminus \{x\})$. The set $U \setminus \{x\}$ is an open neighborhood of $y$ because $X$ is T1, hence there is a point in $U \setminus \{x\} \cap A - \{y\}$. This is also a point in $U \cap A - \{x\}$, so $x \in A'$.  There is a non-T0 space with such a subset: let $X = \{a,b\}$ have the indiscrete topology, and pick $A = \{b\}$. Then $A' = \{a\}$ and $A'' = \{b\}$.  My question is if there is a T0 (but not T1) space with a subset with this property. It does not seem to be possible with the standard T0 spaces I have checked (particular/excluded point spaces, and other simple spaces).


After install ubuntu 15, my clock is missing also I've checked my locale and there is an error too. "locale: Cannot set LC_ALL to default locale: No such file or directory"  I don't know if all there are the same error, or two errors    Sorry for my english :)


An entire function whose real part is bounded must be constant.

Greets  This is exercise 15.d chapter 3 of Stein & Shakarchi's "Complex Analysis", they hint: "Use the maximum modulus principle", but I didn't see how to do the exercise with this hint rightaway, instead I knew how to do it with the Casorati-Weiestrass Theorem, here is my answer:  Define $g(z)=f(1/z)$ for $z\neq{0}$,then by the hypothesis we must have that for any $\epsilon>0$ $g(D_{\epsilon>0}(0)-\{0\})$ is not dense in $\mathbb{C}$, then the singularity at $0$ of $g$ is not essential, this implies $f$ must be a polynomial, but if $f$ is a non-constant polynomial, it is easy to see that its real part must be unbounded, so $f$ must be constant.  I would like to know an answer with the the maximum modulus principle.  Thanks


How should I show that $|a+b|\geq||a|-|b||$?

I am trying to show that $|a+b|\geq||a|-|b||$.  I considered doing an exhaustive process, that is, $a+b \geq 0$, $a+b \leq 0$, and $a+b=0$, and then for each of those considering $|a|-|b| \geq 0$, $|a|-|b| \leq 0$, and $|a|-|b|=0$ (9 combinations)  After doing the first of these ($a+b \geq 0$, $|a|-|b| \geq 0$), I came to the following: $$a+b \geq |a|-|b|$$ and attempting to show this was true.  However, I am unable to show that this is the case.  Additionally, going through such an exhaustive process simply strikes me as wrong or unnecessarily cumbersome.  Any suggestions are appreciated.


Can not lock screen, screen lock never activates, and Super+L does nothing

As stated in the title, when I open Settings and click on Privacy then Screen Lock all of the options are grayed out.    The Blank Screen setting in Power is set to 15 mins. Super+L is set in the Keyboard setting to lock screen, but never works. The only thing that seems to work is the Switch User in the upper right menu.  GNOME shell extensions:   User Themes System-monitor   $ xset q Screen Saver:   prefer blanking:  yes    allow exposures:  yes   timeout:  0    cycle:  0 DPMS (Energy Star):   Standby: 0    Suspend: 0    Off: 0   DPMS is Enabled   Monitor is On


How can I format my active hard drive to NTFS?

I'm trying to install Windows 7 with a 4GB flash drive, but my error that comes up is that my hard drive I'm trying to install on is in ext4. I need to format it to read NTFS. I can't seem to find any topics on how to format an active hard drive. I found a topic that explains how to move Ubuntu to a new drive, but it's a bit confusing to me.


Prove by Induction -Inductive Step problem

The question is prove by induction that $2^n\le n!$ for all $n\ge 4$ So far I have completed the base case so, Base case $n=4$ $ 2^4\le4!$ $16\le24$ Therefore the base case holds Inductive Step Assume F(n) is true $2^{n+1}\le (n+1)!$ $2^{n+1}\le n!(n+1)$ $2\cdot 2^n \le n!(n+1)$ <- I don’t know what do after this to get New Approach $2\cdot n!\le n!(n+1)$   $ by F(n) $ $2^{n+1}\le (n+1)!$


Is Mental Ray available for Blender? Are there any other production quality render options?


How do I run a script as sudo at boot time on Ubuntu 18.04 Server?

How do I run a script as sudo at boot time?  I need to run ethtool --offload <net> rx off to disable the annoying jme udp checksum error message.


Does the verb "provide" always have to be used with "with"? For example,  Can you provide me with some good examples? Can you provide me some good examples? Can you provide some good examples?  I suppose it's a transitive verb, isn't it? Moreover, is the following type of usage correct?  You should provide food for your dog before you go on vacation.  If you could give me some good examples regarding "provide" with different types of usage, I'd appreciate that.


Example for separable space that is not second countable

Sir/madam, How can I prove that the real line with semi open interval topology is separable but not second countable?   Thanks for your answers in advance


I need to prove that $e^x>x+1 \forall x\ne 0$.  Any ideas of hints about how to begin? I don't have any idea except the graphical way.


Find conditional expectation from a 3-dimensional random vector?

I have a three-dimensional random vector $Y$ ~ $N(\mu , \Sigma)$ whose moment-generating function is:  $M_Y(t_1,t_2,t_3)=exp(2t_1+3t_2-3t_3+4t_1^2+5t_2^2+3t_3^2-t_1t_2+2t_1t_3)$.  It was easy to calculate $\mu$  because $M_Y(t)=exp(\mu^Tt+\frac12 t^T\Sigma t), \mu_1 = 2, \mu_2 = 3, \mu_1 = -3.$  Also, $\Sigma=\left[\matrix{8&-1&2 \\ -1&10&0 \\ 2&0&6}\right]$. (If there was any wrong points in this calculation, please let me know).  This is what I have done now....  However, I know only how to calculate the conditional mean when the vector is two-dimentional: $E[Y_1|Y_2=y_2]=E[Y_1]+\Sigma_{12}\Sigma_{22}^{-1}(y_2-\mu_2)$  $VAR[Y_1|Y_2=y_2]=\Sigma_{11}-\Sigma_{12}\Sigma_{22}^{-1}\Sigma_{21}$ (* May anyone let me know the process of having the inverse of covariance in the $\Sigma$?)  For 3D, I still did not get good idea how to calculate $E[Y_1|Y_2=y_2, Y_3=y_3] $ and $VAR[Y_1|Y_2=y_2, Y_3=y_3]$.  For example: $E[Y_1|Y_2=\frac72, Y_3=-2] $ and $VAR[Y_1|Y_2=\frac72, Y_3=-2]$. How is the process changing compared to a 2D one, and where should I start?


The title says all.   Is it true that $\mathbb{Z}/3\otimes_{\mathbb{Z}} \mathbb{Z}[1/2]=\mathbb{Z}/3$?  I know that $\mathbb{Z}/2\otimes_{\mathbb{Z}}\mathbb{Z}[1/2]=0$ because $1\otimes 1=2\otimes \frac{1}{2}=0\otimes \frac{1}{2}=0$.


Use HERE file and redirect output of command

I have the following code in a batch script:  mpirun -np 6 ./laplace <<END 100 100 100 0.01 100 3 2 1 END | tail -n 1 > output   But it isn't working. What I want it to do is to use the HERE file as input to the mpirun command, and then pipe the output to the tail command. However, I think the HERE file and tail output things are getting confused.  How should I write this so that it does what I want?


I am faced with the following problem as homework- a man has 1000 doors. he opens every door, and then he closes every second door. Then he works on every third door- if it's open, then he closes it. if it's  closed, he opens it. Then he works on every fourth door, fifth door, and so on all the way until the 1000th door. I need find the amount of doors left open and their numbers (Door 1, Door 2, etc.).  Can someone please tell me the first step to solving this and what kind of mathematics I need to use.


If $A,B\subset \mathbb{R}$ are closed in $\mathbb{R}$, is $A+B$ also closed in $\mathbb{R}$? I think it is not, but could not find a counter example: any suggestions?


I am broken: reputation graph oddities and rendering issues?

I am broken! Well, maybe not me specifically, but I don't see this issue when looking at other people's reputation pages/graphs, so this isn't something specific to the browser I am using.   This issue only seems to occur in Google Chrome 31 and 32 only (the main browser I use). I tested it in Firefox 26 and Internet Explorer 10 and 11 and could not reproduce it.  So here is my reputation graph, as seen :    As you can see, the reputation history graph along the bottom is white, but if you look at the selected bit you can see the white outline of the bars.  Here is a closer look:    So the bars are definitely there. If you select enough of a time frame using the graph at the bottom, the problem also affects the graph at the top as well:    This shows up as complete white just like the bottom graph until you start to mouse over the bars (which causes the little pop up detailing how much reputation you earned on that day).


C# How to set or copy a new object to a global variable which references a parameter via constructor

Say I have these Classes and variables  public class Human {     public string name; }  public class Home {     public Human m_oHuman = null;      public Home(ref Human p_oHuman) { //note the ref         m_oHuman = p_oHuman;     }      //p_oNewHuman takes over the home     public void TakeOver(Human p_oNewHuman) { //don't need ref, just need copy         m_oHuman = p_oNewHuman; //Won't work as intended.     } }  //Run this code public Human homeOwner = new Human { name = "Sally" }; public Home home = new Home(ref homeOwner) public Human homeStealer = new Human { name = "Daisy" }; home.TakeOver(homeStealer);   What I'm trying to do is pass homeOwner by reference and save that reference in the global variable m_oHuman then later I want to try make homeOwner "point" to homeStealer or at least a copy of homeStealer since it's not passed by ref. But doing it the way I've coded seems to make m_oHuman lose the initial reference, and so homeOwner is still "Sally" when I want it to point to p_oNewHuman.  What I'm thinking I must do, instead of m_oHuman  = p_oNewHuman;, is go through and copy all the variables from p_oNewHuman to m_oHuman.  But with the code I'm really working with, there are many members and classes that I'm trying to make work like the code above and I feel this could become cumbersome having to manually copy object variables. So I'm wondering if there was a better or easier way to achieve this goal.


limit of increasing sequence of measures is a measure

Statement  Let $(X,\Sigma,\mu)$ be a measurable space and let $(\mu_n)_{n\geq 1}$ be a sequence of measure in this space. Suppose that this is a monotone increasing sequence, in the sense that $\mu_n(E)\leq \mu_{n+1}(E)$ for all $E \in \Sigma$, and for all $n$. If we define, for every $E \in \Sigma$  $\space$  $\mu(E)=\lim_{n \to \infty} \mu_n(E)$,   prove that $\mu$ is a measure.  The attempt at a solution  I am having problems trying to prove the countable additivity property, which is, if $\{E_i\}_{i \in \mathbb N}$ is a countable collection of pairwise disjoint sets in $\Sigma$, then  $\mu(\bigcup_{i \in \mathbb N} E_i)=\sum_{i \in \mathbb N} \mu(E_i)$  In this particular case, the property is satisfied if and only if  $\lim_{n \to \infty} \mu_n(\bigcup_{i \in \mathbb N} E_i)=\sum_{i \in \mathbb N}\lim_{n \to \infty}\mu_n(E_i)$  Each $\mu_n$ is a measure, so  $\lim_{n \to \infty} \mu_n(\bigcup_{i \in \mathbb N} E_i)=\lim_{n \to \infty} \sum_{i \in \mathbb N} \mu_n(E_i)$.   How could I go on from here? I know I must use the fact that $(\mu_n)_{n \in \mathbb N}$ is a monotone increasing sequence, I would appreciate any help.


New to ubuntu, new to WSL, I'm not even able to get ping to work.  I've just installed ubuntu and it seems to be running fine. I've set proxy using   export http_proxy=http://mycompany.net:8080   Apt-get-upgrade seemed to work but with "0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded."  Ping just locks up.  Also, as recommended, tried  sudo apt-get --print-uris install PROGRAM   which resulted in 'E: Unable to locate package PROGRAM'


Why I am unable to join separate meshes together?

I downloaded a Sims 3 3D model mesh to make custom clothes for the game Sims 3.  but I noticed all the parts of the models body were separated including the eyes, head, and feet. So I tried to merge all the separated meshes together by pressing the join key but  I got the error no mesh data to join.  I don't why or  how to solve this issue and its really makes things harder for me. If you know a solution to this problem,  please let me know. I must be doing something wrong.  Here is the blend file of the model:


Why can I use static_cast With void* but not With char*

I know that  is primarily used going to or from a char*.  But I was surprised to find that  could do the same with a void*. For example:  auto foo "hello world"s; auto temp = static_cast<void*>(&foo); auto bar = static_cast<string*>(temp);   What do we gain from using reinterpret_cast and char* over static_cast and void*? Is it something to do with the strict aliasing problem?


I have recently started using blender and one of the models I'm working on has dark shadows along edges. I started this model from scratch. I can't remember them being there when I first started the model, but I had trouble joining areas together and think I've pressed something I shouldn't have. However, there are so many options I'm not sure what I did.  Here is an image of what I mean   The one on the left has the shadow. As a test I started a new model, which is on the right in the image, and as you can see it doesn't have any shadows.  Also, occluded vertices partially show through the model. Occlusion doesn't work properly.   In orthogonal view small darkened triangles appear along the the edges.    I don't really want to start the model again from scratch so any ideas on how to remove this shadow would be great. Thanks.


Minecraft launcher giving Java error "the trustAnchors parameter must be non-empty"

On Ubuntu 17.10, the Minecraft launcher keeps giving me "the trustAnchors parameter must be non-empty" error. The full log is here:  user@hostname:~$ java -jar Downloads/Minecraft.jar  Bootstrap (v5) Current time is Oct 11, 2017, 10:48:39 AM System.getProperty('os.name') == 'Linux' System.getProperty('os.version') == '4.13.0-12-generic' System.getProperty('os.arch') == 'amd64' System.getProperty('java.version') == '9-Ubuntu' System.getProperty('java.vendor') == 'Oracle Corporation' System.getProperty('sun.arch.data.model') == '64'  Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 2/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 3/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 4/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 5/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 6/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 7/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 8/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 9/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/launcher.pack.lzma (try 10/10) Exception: javax.net.ssl.SSLException: java.lang.RuntimeException: Unexpected error: java.security.InvalidAlgorithmParameterException: the trustAnchors parameter must be non-empty Unable to download remote file. Check your internet connection/proxy settings. FATAL ERROR: net.minecraft.bootstrap.FatalBootstrapError: Unable to download while being forced     at net.minecraft.bootstrap.Bootstrap.execute(Bootstrap.java:95)     at net.minecraft.bootstrap.Bootstrap.main(Bootstrap.java:381)   Please fix the error and restart.   I have tried the Minecraft launcher from both the Minecraft website and from ppa:flexiondotorg/minecraft.  I have tried openJDK-8, openJDK-9 and Oracle Java 8, all giving me the same error.  A similar problem was posted a while ago here: . The best solution seems to have been to run sudo update-ca-certificates -f. However, running this command does not solve the issue for me.


Numbering of the rows in the table (tabularx)

How to make a numeration of the rows in the table(tabularx) automatically?  I have a table, and in the first column I have numbers of the rows, right now I just type this numbers manually, but is there is any command which can do it automatically?  \documentclass{article} \usepackage[utf8]{inputenc} \usepackage[russian]{babel}  % Включаем пакет для поддержки русского \usepackage{multirow,tabularx} \usepackage[a4paper,margin=1in,landscape]{geometry}  \begin{tabularx}{\textwidth}{ |X|X|X| } \hline №  & Характер работ & Ответственные лица \\ \hline 1.  & Покрасить стену & Иванов И.И. \\ \hline 2.  & Покрасить стену & Петров И.И. \\ \hline 3.  & Сидоров & Сидоров А.О. \\ \hline \end{tabularx}  \end{document}


split a large file to new file with unique file names

I need to split a file into unique file names. I can do it with sed command eg,  sed -n '/scaffold135_/w 135-scaf.txt' input file.txt but it's time consuming so I need a smart way to do it faster. Below is an input sample (the original file has one million lines):  scaffold1_115,T,N,N,N,N,A,N,N,N,N,N,N,T,N,T,T,N,A,A,N,N,A scaffold1_123,A,N,N,N,N,G,N,N,N,N,N,N,A,N,A,A,N,G,G,N,N,G scaffold1_140,C,N,N,N,N,C,N,N,N,N,N,N,C,N,C,C,N,T,C,N,N,C scaffold2_161,G,N,N,N,N,G,N,C,N,N,C,N,G,N,G,G,N,G,G,C,N,G scaffold2_162,C,N,N,N,N,C,N,T,N,N,T,N,C,N,C,C,N,C,C,T,N,C scaffold2_180,C,N,N,N,N,C,N,T,N,N,C,C,C,T,C,C,T,C,C,C,N,C scaffold2_194,C,N,N,C,N,C,C,C,C,C,C,C,C,C,T,C,C,C,C,C,N,C scaffold3_195,G,N,N,G,G,C,G,G,G,G,G,G,C,G,C,G,G,C,C,G,N,C scaffold3_234,T,N,A,T,A,A,T,T,T,A,T,A,A,T,A,A,T,A,A,T,N,A scaffold101_282,C,T,T,T,C,C,T,C,T,C,C,C,C,T,C,C,T,C,C,C,N,C scaffold101_371,T,T,T,T,T,C,T,T,T,T,T,T,T,T,T,T,T,T,T,T,N,C scaffold101_372,T,T,T,T,C,C,T,T,T,T,T,T,T,T,T,T,T,T,T,T,N,C   The lines are unique. I want lines specific to each scafold into a separate file, say all lines that start with scaffold1_ into a file named scaffold1.txt and so on until scaffold10156.txt which contains the lines starting with scaffold10156_


Why do I get a "seam" using Mirror modifier?

I started using Blender a few weeks ago and right now I'm starting my first project without a tutorial. I'm starting to create a character and the first thing that came to my mind was "It needs to have symmetry", so I used a Mirror modifier on my object and it has this "seam". In the image I used a Sphere because it is much more noticeable.  So, how can I fix it? And why does this happens?


At our regular supermarket this morning I noticed that they have put stickers on the check-out conveyor which say 'Lay bottles this way' with an arrow indicating that they want them parallel with the belt.   I don't think one can form the imperative of 'lie' in that way. 'Laying' wine bottles sounds potentially painful on the abdominal muscles. I think they should say 'lie bottles this way'.   Does anyone agree?


Indian Citizen travelling on advance parole to USA

I am an Indian citizen who lives in the USA, travelling from USA to India through ROME FIUMICINO, ITALY airport and returning from India to USA through the same airport in Italy. I am travelling with an advance parole document and don't have a visa stamped in the passport.  My stopover is around 3 hours.  Please advise if I need a transit visa for Italy or can travel to the USA (on return) based on approved advance parole.


Suicidal man is sent to explore a remote planet with a robot to help him

A miserable man who is going to slice his wrists in the bathroom gets an offer to explore a remote planet. He’ll be accompanied by a robot who’s supposed to help him, but instead, as the story progresses, the robot becomes more and more of a nuisance. They have to fight some winged creatures and meet a subterranean tribe that lives in tunnels. Some similarities with Robinson Crusoe.  Could be Sheckley, but I’m not sure.


Are there emulators for quantum computers?

Is there any way to emulate a quantum computer in my normal computer, so that I will be able to test and try quantum programming languages (such as )? I mean something that I can really test my hypothesis and gets the most accurate results.  Update: I'm not really looking for simulating a quantum computer, but I'm not sure if its possible to efficiently emulate one on a normal non-quantum based PC.


Prove that the product of some numbers between perfect squares is $2k^2$

Here's a question I've recently come up with:      Prove that for every natural $x$, we can find arbitrary number of integers in the interval   $[x^2,(x+1)^2]$ so that their product is in the form of $2k^2$.   I've tried several methods on proving this, but non of them actually worked. I know, for example, that the prime numbers shouldn't be in the product. I was also looking for numbers $x$ so that between $x^2$ and $(x+1)^2$ there is actually the number $2k^2$ for some natural $k$. If we find all of these numbers, then we should prove the case only for the numbers which are not in this form. These $x$s have this property: $x^2<2k^2<(x+1)^2$ leading to $x<k\sqrt 2<x+1$ and $x\frac{\sqrt 2}{2}<k<(x+1)\frac{\sqrt 2}{2}$. This means there should be a natural number between $x\frac{\sqrt 2}{2}$ and $(x+1)\frac{\sqrt 2}{2}$. I've checked some of the numbers that aren't like that with computer, and they were: $3,6,10,13,17,...$. the thing i noticed was that the difference between the two consecutive numbers of that form, is either $3$ or $4$. I think this has something to do with the binary representation of $\frac{\sqrt 2}{2}$ but I don't know how to connect it with that. I would appreciate any help :)


properties of the smallest integer divisible by all integers up to $n$

What is the name and what are the properties of the smallest integer divisible by all integers $1\ldots n$?  Clearly, $n!$ would do the trick, but it is generally not the smallest such number.  So far, I only came up with a recursive definition, i.e.  $f(n)=\frac{n\,f(n-1)}{\mathrm{gcd}(n,f(n-1)}$ starting with $f(1)=1$.  This nicely gives e.g. the first 12 such numbers: 1, 2, 6, 12, 60, 60, 420, 840, 2520, 2520, 27720, 27720.  Someone must have come across this before... Thanks.


How to use external hard disk in both Windows and Mac OS X?

I have one external hard drive (Seagate 320 GB). I have used my hard drive in a Windows XP system and it works fine (Read and write). But when I used it on a Mac, I couldn't write any file on the disk and could read only.   How can I use my external hard disk on Mac OS X (both read and write)?


What Mutual Funds does Dave Ramsey Invest in?

Heard Dave Ramsey speaking the other night on his growth mutual fund strategy and he mentioned  reading one of his fund's prospectus and said this fund had a 78 year history and 11.94% average return over those 78 years.  Tried some searches but not sure how to find this specific fund. Anyone know any tools/tips to find this fund or other like it?


help, it keeps saying "failed to fetch" fetching the upgrade failed. There may be a network problem" but i am connected to the internet with lan.


Why can't we use the word "problem" in titles?

Recently this Mathematica question was posted,  The reason for the odd split in the word pro-blem is there is a filter preventing its use in titles. For the most part, I can see where this is useful, as almost by definition all questions asked here are about problems. But, this filter prevents a legitimate use of the word that is accepted in the physics and math communities.   Is there a way around this, or is the problem so great that its legitimate use must be suppressed also?


In a tungsten filament lamp, electrons travel through a high resistance path,due to which the temperature is increased. Now why does it emit light , is it because of the transitions of electrons from one energy state to another or is it radiation because of temperature. And are these two related in any way?Does light from a heated object has different reasons than the light from transitions?And also if electrons are ionised already how are the transitions happening?


Vertical alignment of the top line in \sqrt

When using \sqrt, the top line of the square root symbol seems to be closer to the enclosed text for some text than for others.  It even seems to line up differently with the left "check mark" portion of the symbol.  It seems to have something to do with the dip down of the y below the baseline of the text.  You can see the difference in the following, which I'm compiling with xelatex.  \documentclass{article} %\usepackage{amsmath} same problem without amsmath \begin{document}  $\sqrt[3]{918y}$ $\sqrt{34}$ $\sqrt{34y}$ \end{document}    Is there any way to fix it so that this doesn't happen, and \sqrt compensates for the different baselines?


How can I calculate normals using a vertex and index buffer?

Is it possible to calculate normals using the positions in a vertex buffer and index buffer? Would someone show pseudocode for the algorithm?


Sharing my 240V 30amp between two dryers

We are running a clothes dryer in the lower level of our home. We are installing a washer and dryer on our main level. Can I split the power feed between both dryers and what can I use and where can it be bought. We only want to run one dryer at a time when needed.


How to identify the C terminal on my HVAC

As you can see I have a Y G W R/2 C/3 D/1 terminals on my HVAC. I am planning to change my thermostat to one that requires a c line. There are 2 spare lines available, however I am not sure which is the C terminal. This is a forced air heating (gas) cooling(electric) system. I am guessing that its the C/3 terminal. Any help would be appreciated.


Given an arbitrary set $A\subset\mathbb R^n$, why do all extreme points of the convex hull $\operatorname{conv}(A)$ lie in $A$?  (An extreme point of a convex set is defined as one that cannot be written as a strictly convex combination of two distinct points of this set.)


how to make logos like these? any tutorial online?

I am a student of graphics, and was looking for some inspirational logos and came across these, they look beautiful and I tried to make one myself but failed. How can anyone make such perfect logos? with exact same width and height exact distance. What are these logos called? Is there any tutorial online? Can someone please help me in learning how to make these types of logos? Do i need some kind of illustrator script or action for this?


Whats the problem with my laptop? cant start Ubuntu

While trying to start my Lenovo laptop I get the screen you see in the image below, I’m not able to to do any other thing or get the Ubuntu console. Also I'm not able to start using the Ubuntu CD.


Server Potentially Compromised -- c99madshell

So, low and behold, a legacy site we've been hosting for a client had a version of FCKEditor that allowed someone to upload the dreaded c99madshell exploit onto our web host.  I'm not a big security buff -- frankly I'm just a dev currently responsible for S/A duties due to a loss of personnel.  Accordingly, I'd love any help you server-faulters could provide in assessing the damage from the exploit.  To give you a bit of information:  The file was uploaded into a directory within the webroot, "/_img/fck_uploads/File/".   The Apache user and group are restricted such that they can't log in and don't have permissions outside of the directory from which we serve sites.  All the files had 770 permissions (user rwx, group rwx, other none) -- something I wanted to fix but was told to hold off on as it wasn't "high priority" (hopefully this changes that).  So it seems the hackers could've easily executed the script.  Now I wasn't able to actually locate c99madshell.php itself -- only a bunch of other HTML files containing russian text and a few .xl and .html files with inline PHP that were renditions of the madshell hack.  Upon doing a bit of research, though, it looks like the hack destroys itself after execution -- great.  Anyway, my initial assessment would be this:   Not necessary to rebuild the entire host, as given the isolation of the apache user / group, they shouldn't have been able to get system level passwords. It is necessary to fix this vulnerability by restricting uploads to not have the execute permission, updating the FCKEditor version to correct the original exploit target, and add server-level configuration that denies execution of PHP script within the uploads directory. I should change the DB passwords for the app -- given the configuration file for the database connection lies within the web-root, the hacker most likely could've grabbed it and with it the DB password.   Anyway, please provide any input you guys have regarding what I should tell the bossman.  Obviously it'd be ideal to avoid rebuilding the whole host -- but if thats what we have to take to ensure we're not running a hacked machine, then thats what its going to take.  I really appreciate your guys help.  Also don't hesitate to ask for more information (I'd be happy to run commands / work with you guys to assess the damage).  God damn hackers :(.


I have some own theorem environments. And my theorems are numbered like the chapter. Now I would like to use autoref with that. But it does not work like it is described here () with aliascnt. So how can I get that?  \documentclass[ngerman,halfparskip,12pt,pointednumbers]{scrreprt} \usepackage{babel} \usepackage[utf8]{inputenc}  \usepackage[T1]{fontenc}  \usepackage{amsmath,amsfonts,amssymb,amsthm,bbm} \usepackage{hyperref} \newtheoremstyle{absatz}     {17pt}{10pt}{}{-1pt}{\scshape\bfseries}{.}{\newline}{}  \theoremstyle{absatz}  \newtheorem{satz}{Satz}[chapter] \newtheorem*{satz*}{Satz} \newtheorem{lemma}[satz]{Lemma} \newtheorem{corollar}[satz]{Korollar}   %\renewcommand*{\theoremautorefname}{Satz} \begin{document} \begin{satz} \label{Satz} text text theorem \end{satz}   In \autoref{Satz} we have shown... \end{document}


Request root privilege from within a script

I have a script which can run as sudo script.sh or pkexec script.sh  It would be much nicer from the user point of view if the script asked for the password from the user when just running it by name script.sh.   How can I "embed" request to pkexec or sudo to run the whole script with root privilege?  Note that running everything with sudo sh -c might not be the best solution as I have functions in the script.


Equivalent of R-squared in Generalized Linear Model Regression Results?


I work in LyX. There's a default macro for the kernel: \ker which has nice spacing if I put something after it, compared to \text{ker}. I'd like to have macros with the same nice spacing for the image, coimage, and cokernel, respectively im, coim, coker.


Is there a difference between "geographic" and "geographical"?

I am wondering if there is a difference between "geographic" and "geographical". My colleague, although not a native English speaker, informed me that there is a difference between "historic" and "historical", such as described here: , and that could extend to other terms.  The context is corporate diversification, where firms that are active in different countries are said to engage in "geographic" or "geographical diversification".  To clarify the difference to the existing question:  Furthermore: If there is a difference and I should use one, but not the other term, then how does that apply to "industrial diversification"? Would this become "industry diversification"?  More generally, are such differences between words as with "historic" and "historical" existing for all adjectives, or only a small number of them? How can these be recognized and constructed?


Short story about the human race pooling together resources to reach dying race

It's a great story I read several years ago, and was written in the form of newspaper articles and short narrative.  The humans receive a transmission from an alien race asking for help, and they put their differences aside and use all the nukes to make a spaceship. The ship gets to the coordinates only to find that the planet isn't there, but a galactic organization appears and says that this was all a test to see if the humans were suitable to enter the galactic affairs.


I am using the following formula in a column of cells: `=if(XXnn="";"";timevalue(now()))`  (nn according to the row XX to the column). This enters the time correctly as a value is entered in the relevant cell. However, when entering a value in any other cell in the sheet, the time value already entered is then also changed to the timevalue(now()). I see from  that the (NOW) function is volatile but does anyone have a work around to suggest? How can one use this formula so that it is persistent and doesn't change when another cell is accessed?


$$\int \sqrt{x+\sqrt{x^2+2}}\ dx$$  I tried various solving methods but I am not coming forward. I unformed the term also to ${x+\sqrt{x^2+2} \over \sqrt{x+\sqrt{x^2+2}}}$  and even multiplied with ${\sqrt{x-\sqrt{x^2+2}} \over \sqrt{x-\sqrt{x^2+2}}}$.   Trigonometric and hyperbolic substitution didn't help either.


please tell me when multiple varibles are returned which one gets stored?

I came across this code and want to know what this line [X] will it return:  int add_multiply(int a, int b) {   int p, q;   p = a + b;   q = a * b;   return (p, q); //X } void main() {   int b, a = add_multiply(1, 2);   b = add_multiply(3, 4);   printf("%d%d", a, b); }


Computer wakes by itself, but wake source is unknown

I have an interesting problem. I am using Windows 8.1 on my PC and I have WOL enabled from my BIOS and my LAN card settings and it works just fine.  But, since a couple of weeks back, my computer turns on by itself in the middle of the night.  Two nights ago, after it woke me up because of the noise, I removed the LAN cord and everything was well until the next morning when I powered the PC myself. I also thought it could be a peripheral, so from Device Manager I went through every device there (apart from the LAN card, which I need because of the WOL), disabling Allow device to wake the computer from "Power Management". Also, in the LAN settings, I checked and the network card can be wake the PC up just by using Magic Packet or Pattern Mach.   The problem persisted last night (it woke around 5am).  I started reading forums and saw the idea of looking what last turned on my PC, so I checked with powercfg -lastwake and it returned the following:   Wake History Count - 1 Wake History [0]  Wake Source Count - 0   Because of the answer, I couldn't find a thing, therefore I checked the Windows logs, filtering them by Power Issues. I found the last wake my PC  experienced, and the log was as it follows:   The system has returned from a low power state. Sleep Time: 2014-05-08T23:38:33.848063300Z Wake Time: 2014-05-09T01:56:48.134397800Z     Wake Source: Unknown   This is the reason I have posted the issue here, even though there are many posts about this. I didn't want to repost, but I never found this same problem (with wake source unknown) in any post or forum.  I hope someone has an idea of what may be the problem.


To convert String to integer, I know there is a function atoi() but i found this one helps too! Please explain this  int h1 = (int)str[1] - '0'; I founded this here


From Putnam and Beyond. My question is, how does this proof work? I'd like to know more about the intuition behind its mechanics.  Prove that there is no polynomial $P(x) = a_n x^n +  a_{n-1} x^{n-1} + \ldots  + a_0 $, with integer coefficients and of degree at least 1 with the property that $P(0), P(1), P(2), \ldots ,$  are all prime numbers.  Solution:     Assume the contrary. Let $P(0) = p$ with $p$ prime.Then $a_0 = p$. And $P(kp)$ is divisible by $p$ for all $k \geq 1$.Because we assumed that all these numbers are prime, it follows that $P(kp) = p$ for $k \geq 1$.Therefore, $P(x)$ takes the same value infinitely many times, a contradiction.Hence the conclusion.


I was thinking if it was possible to create a polynomial that would be periodic all over the reals, since polynomials can be periodic on an interval. I then I found out the following function:  $$P(x)= x \prod_{k=1}^\infty (x-k)(x+k)$$  I wonder if that function can be considered as polynomial since it's degree will be $\infty$. Then is this function periodic of period 1? Since the product is to infinity, $P(x+1) - P(x) = 0$. Moreover, how this function look like? I couldn't trace it on the Mac Grapher app nor Wolfram alpha doesn't understand my commands.


Include year in date field of 'activity' tab

Here's :        At the moment, the latest entry there is October 13, which would be mistaken to mean October last year (2012), but it actually is October 2010. This applies to all the filters in the activity tab.