In a multi-label classification, the accuracy is commonly defined as [1] $$ \text{Accuracy}(\boldsymbol{Y},\, \boldsymbol{Z}) := \frac{1}{n} \sum_{i=1}^n \frac{\lvert Y_i \cap Z_i \rvert}{\lvert Y_i \cup Z_i \rvert}, $$  where $Y_i$ is the set of predicted labels for sample $n$ and $Z_i$ is the corresponding set of ground-truth labels. If I get things right, this means that we divide the number of correctly classified labels per sample by the number of labels that are either predicted or given as ground-truth per sample and average over. For example, if $\boldsymbol{Y} := ([0,0,1],\,[1,0,1])$ and $\boldsymbol{Z} := ([0,0,0],\, [1,0,1])$, this would give $$ \text{Accuracy}(\boldsymbol{Y},\, \boldsymbol{Z}) = \frac{1}{2}\left(  \frac{0}{1} + \frac{2}{2} \right) = \frac{1}{2}. $$  To me, this is unintuitive, since the classwise accuracies are $1$, $1$ and $\frac{1}{2}$ (in that order). The problem is that the definition of multi-label accuracy does not reflect correctly classified absence of labels, whereas the classwise accuracy does. The same is true for multi-label recall and precision as defined in [1].  Is it really like that or do I get the definitions wrong? Can you recommend any multi-label measures that suit better for problems, where correctly classified absence of labels is equally important as presence (apart from the Hamming Loss)?  [1] Sorower, Mohammad S. "A literature survey on algorithms for multi-label learning." Oregon State University, Corvallis 18 (2010).


How many non isomorphic groups of order 30 are there?

Let $|G|=30$.  I have prove that there is the only subgroup of order $15$, which I'll denote $H$. Now I do know how to classify the group.  After thinking, I made the following steps.  1) Possible order of subgroup $K$ of $G$ of order 2 are 1, 3, 5, 15.  Case 1. if $G$ contain only one element of order 2, then $G \cong Z_{30}$.  Now I cannot solve for the next steps. Please give me any hints or any other method.


I want to install Ubuntu on my device, but when I run:  sudo ubuntu-device-flash touch --channel=ubuntu-touch/stable/ubuntu --bootstrap    I get this back:  2015/06/28 23:13:09 Expecting the device to be in the bootloader... waiting 2015/06/28 23:13:09 Device is |D2302| Device D2302 not found on server https://system-image.ubuntu.com channel ubuntu-touch/stable/ubuntu    How I can install Ubuntu on my device?


Alternative to SQL Server Management Studio and Azure Data Studio to initially change my password

Background  I'm having to connect to a customer's Microsoft SQL Server. I generally don't need to do much in databases besides your average SQL, so using the database features in IntelliJ IDEA have so far been more than sufficient for various PostgreSQL and Orcacle databases. In this case though I was given a heads-up that I will have to change my password first, and when I use IDEA to connect with the credentials I received it does indeed reject them and gives me an error message saying I need to change my password. I was also told to use SQL Server Management Studio (SSMS) to do so.  Problem  SSMS is only for Windows, I'm running a Mac. The SSMS download page refers to Azure Data Studio for use on a different OS. An initial try of the latter did not let me change the password though. Even if I eventually find a way to do it, is there really no other easier way to do this that doesn't involve installing another full-blown db tool that I have no intention of using in the long run? Or worst case: buy a windows computer for the sole purpose of installing SSMS so I can change a password? Surely there must be a bunch of Mac- or Linux-using DBA's that know of a simple command-line tool or alike that allows them to change their password initially on a Microsoft SQL Server, after which they just use their favorite db management tool to access it?  Edit: Note on "duplicate"  I disagree that this is a duplicate of  because:   That question involves an expired password, while I was never able to log in in the first place, nor able to run any sort of SQL prior to logging in That question involves someone already using SSMS, whereas I've specifically pointed out I cannot use it and I'm asking for an alternative   Additional clarification   When I said customer, I meant a client that has data that I need to pull. I do not have any sort of admin access to the VM or SQL Server beyond the credentials I was provided The error I'm getting is not a notification while I'm logged in. It's an error preventing me from even connecting, so I cannot run any other SQL or commands whatsoever


I have the following command to get SQL data from a fmb (Oracle Forms) file  strings test.fmb | egrep -i '(select|insert|update|delete)'   The output is spool in the window, how can I spool the output to a file?


Question title overlap in new design when title is longer

Today I noticed that in new design view count is getting overlapped with question title on scifi.se for longer title:    But it's not site specific as same problem happen in Beta site too ( Hinduism.se):    That's why asked in main meta.


What is ${\partial\over \partial x_i}(x_i !)$ where $x_i$ is a discrete variable?  Do you consider $(x_i!)=(x_i)(x_i-1)...1$ and do product rule on each term, or something else? Thanks.


Can "short of" be used with a specific amount (cash)?

In another  regarding a difference between short on and short of, the  says the following:     ... But this is not always the case. A person can be short on/of money,   but lacking a specific amount, someone can only be €10 short or short   €10. This construction never uses a preposition.   but is that really true? I can see sentences like "I am short of 10 dollars" quite often.


Prove by contradiction that any prime number is either in the from of $ab+1$ or $ab+5$.

It says:     Prove by contradiction that any prime number is either of the form of $ab+1$ or $ab+5$.   And this was all. But it seems both belong to $\mathbb{N} \cup \{0\}$. Because otherwise it wouldn't hold for $2$ which is prime.  What the problem says is to say:  $$(p\neq ab+1)\wedge (p\neq ab+5)\implies p\text{ is not prime}$$  I tried to show it would then be written as the product of two numbers and thus not prime. But up to what number should I do that?  Stuck.


How to handle ConcurrentModificationException while removing items in collection?

I am trying delete a String that occurs 5 times in my List. This is what I've tried:  for(String obj : list1) {     if(new ArzList().countOccurrence(list1, obj ) == 5)     {         list2.add(obj);         list1.removeAll(Collections.singleton(obj));                     }    else{         list3.add(obj);         list1.removeAll(Collections.singleton(obj));    } }   But I get java.util.ConcurrentModificationException each time.   How do I solve it?


SQL Update column from one table to another

I'm a beginner in SQL however I have two tables one LibraryTable where I have list of songs, and another table called Playlist, I'm using netbeans to program a prototype jukebox, and I can add songs from the Library to my playlist, and I can increment playcount of all the song that where added to the playlist, however both LibraryTable and Playlist have a column called playcount, I want know how I would go about updating the playcount column in LibraryTable with the the playcount column in my Playlist table.


Following code not working in LaTeX : $\{f^'_n\}$

Why does the following code does'nt work when i am using PDFLaTeX or just LaTeX ? I tried it in different editors as well.  This is the code   $\{f^'_n\}$   Surprisingly it works on Math.SE site


NullPointerException raised eventhough it is not NULL

NullPointerException raise while trying update a excel cell using Apache POI.  Particular cell that I want to update has some value but I can't update due to exception.   String excelFileName = "D:\\TempLocation\\Marks.xlsx";//name of excel file String sheetName = "Sheet1";//name of sheet XSSFWorkbook wb = new XSSFWorkbook(); XSSFSheet sheet = wb.getSheet(sheetName) ; System.out.println(regNo+ " " + cellNo); Cell cellToUpdate = sheet.getRow(0).getCell(0); cellToUpdate.setCellValue(mark); FileOutputStream fileOut = new FileOutputStream(excelFileName); //write this workbook to an Outputstream. wb.write(fileOut); fileOut.flush(); fileOut.close();   this is my code. Exception raised at this line:    Cell cellToUpdate = sheet.getRow(0).getCell(0);


7a. Prove by Mathematical Induction that $4^{n+1}+5^{2n-1}$ is divisible by $21$.


The width of the backdrop is 20 ft. It will be projected onto a wall. What size should the photoshop dimensions and the resolution be? This is not going to be a print file, it is going to be displayed digitally!


Is there any point in photographing directly to black & white?

As opposed to photographing in colour, then having all the freedom to edit it afterwards?


So, I'm making a free op minecraft server. I don't want everyone being able to stop the server or ban anyone, so should I set the op level to 2? SuperOP will be able to ban, so obviously level 3. Owner will be level 4.


How do I set a static IP address in Windows?

If I do not have access to the router / DHCP server to create a static reservation (i.e. asking the router / DHCP server to set aside a specific IP address when a certain MAC address requests it), how can I set my Windows 7 workstation to have a static IPv4 address?


How to prove that for all $m,n\in\mathbb N$, $\ 56786730 \mid mn(m^{60}-n^{60})$?

How to prove $\forall m,n\in\mathbb N$:  $$ 56786730 \mid mn(m^{60}-n^{60})?$$  Thanks in advance.


Prospective PhD contacts potential supervisor but receives no answer after 2-3 emails, what to do?

Say a prospective PhD has a high reply rate (90-95%) to first contact emails with potential superviors. He/She has a well thought out e-mail, but a particular professor (here: USA) that is in the top preferences does not reply after two to three e-mails that were sent within a time frame of three months. I also followed the instructions on the professor personal website in the section "prospective PhD students". The student has already contacted some of the advisor students and has received positive feedback about the professor.  Should the student just give up and move on? Should the student keep trying?  Aside from the obvious "I have too many incoming e-mails to answer" or "I am out in the field", what could create a no response behavior from the professor?  I have seen the simplistic answer "move on, bad advisor, doesn't have time, etc". But this seems a contradiction in this case. The PhD students like the professor and say he/she is personable and no e-mail response after a few well written emails.


I am trying to derive the speed of a wave equation $$v = \sqrt{F/\mu}$$ starting from a segment of string under tension with a force of $F$ in which a pulse moves with a speed of $v$. Can someone show me how to derive this equation?


Story About Time Travel Using a Gate on the Sun

When I was in high school (6 or 7 years ago), one of the short stories that we read out of the text book had to do with an alien civilization that had discovered time travel.   They had managed to land on and explore the surface of their sun, and had found a gate there that allowed travel into the future. They copied this technology and it formed a large part of their society. The main character was an agent of an organization meant to keep paradoxes and such from occurring.   I remember that he explains that his job is strange, because since a successful mission means the erasure of the event that caused it, he had no memories of ever actually doing his job. He simply knew what it was and received payment for it. The story also mentions that the "last gate" at the "end of time" was so named because no one who went through it had ever returned. The era that this gate existed in was constantly in a state of flux due to minor changes in the timeline.  If anyone knows the name of this story or the author, it would be a great help. I've been trying to figure out what it is for around a year now, and no one I've spoken to about it has ever heard of or read it.


Website is loading with corrupted data once a while

I have pushed one of my site to LIVE, but once a while when a page loads it is being displayed as below snapshot, but after sometime it gets corrected automatically.  Can one please tell me what could be the reasons for this and how can i make sure to fix this issue so that it is not repeated in future.    Have also used the security plugin "iThemesSecurityPro" to protect my website from malware.   WordPress version used is 4.7.5


Question marks instead of quotation marks in references

I am using BibLaTeX and Babel (catalan) and I get a weird error in the bibliography:the quotation marks are replaced by question marks. If a deactivate Babel everything works.  Babel:  Code:  \documentclass[12pt,a4paper]{article} \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage{csquotes} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{setspace} \usepackage[backend=bibtex,sorting=none]{biblatex} \usepackage{graphicx} \usepackage[margin=2cm]{caption} \usepackage[catalan]{babel} \usepackage{float} \usepackage{wasysym} \usepackage{pifont} \onehalfspacing \usepackage[top=0.79in, bottom=0.79in, left=1.18in, right=0.79in]{geometry} \renewcommand{\thefootnote}{\arabic{footnote}} \addbibresource{bib.bib} \begin{document} [...] \printbibliography \end{document}   Result:   Without Babel:  Code:  \documentclass[12pt,a4paper]{article} \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage{csquotes} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{setspace} \usepackage[backend=bibtex,sorting=none]{biblatex} \usepackage{graphicx} \usepackage[margin=2cm]{caption} %\usepackage[catalan]{babel} \usepackage{float} \usepackage{wasysym} \usepackage{pifont} \onehalfspacing \usepackage[top=0.79in, bottom=0.79in, left=1.18in, right=0.79in]{geometry} \renewcommand{\thefootnote}{\arabic{footnote}} \addbibresource{bib.bib} \begin{document} [...] \printbibliography \end{document}   Result:


"Most countries in the world" or "Most of the countries in the world"?

Most of is used to say quantity of a thing in general, and Most of the is used to say quantity of a specific thing. I think in the world is a specific thing which makes me think that Most countries in the world is right, but I'm not sure.   So what is the right answer?


What must be done to guarantee continued IP address ownership?

There is a pretty high-level of guarantee that we can have continued possession of  a chosen domain name as long as we renew it from our registrar (and provided that our registrar is not corrupted/incompetent).  For example, if we purchase a domain name my-domain-name.com and pay our annual renewal fees on time, it's unlikely that we will lose ownership of the domain name in the future.  Is there such a guarantee for continued possession of IP addresses?  For example,  has publicly stated that the specific IP addresses  8.8.8.8 and 8.8.4.4 belongs to him. Then, what are the necessary steps he must take to ensure that these addresses continue to belong to him in the future?  How much "guarantee" does future IP address ownership has?


What special implication does ‘totally’ have in “He’s totally going to call you”?

There was the following sentence in an article titled, “Like, Degrading the Language? No Way” in New York Times (April 5), in which the author says Americans are moving backward on language:     “(Like the use of ‘like’) the use of “totally” mines the same vein.   “He’s totally going to call you” does not mean “He is going to call   you in a total fashion.” It has a more specific meaning, although only   handled subconsciously by speakers, as so much of language is. “He’s   totally going to call you” contains an implication: that someone has   said otherwise or that the chances of it may seem slim at first glance   but in fact aren’t. As with “like,” “totally” tracks and nods to the   opinions of others. It’s totally civilized.”      Although the author explains “totally going to call you” contains an implication of someone having said otherwise, I’m not still clear with the meaning of “He’s totally going to call you.”   What does it mean? He’s totally going to call you “what”?   How does “He’s totally going to call you.” differ from “He’s going to call you.”? Is this expression (use of totally) ubiquitous today as the author asserts?


combining threeparttable and tabu results in error

While working on my first ever Latex document I have been looking for a way to add notes to tables. An answer to another question suggesting using threeparttable. Regardless of whether I add the tablenotes section, I get an error:   Error in thesis.tex (line 96): Extra }, or forgotten \endgroup. \endtabular ->\TPTsav@endtabular \TPT@endtabhook l.96 \end{tabu} I've deleted a group-   closing symbol because it seems to be spurious, as in `$x}$'. But perhaps the } is  legitimate and you forgot something else, as in `\hbox{$x}'. In such cases the way to  recover is to insert both the forgotten and the deleted material, e.g., by typing  `I$}'.    My MWE looks like this:  Preamble:  \documentclass[man, natbib, a4paper, draftfirst, twoside, 12pt, floatsintext]{apa6}  %---------TABLES--------- \usepackage{booktabs} \usepackage{tabu} \usepackage{threeparttable} %indents in tables (custom command) \newcommand*{\TableIndent}{\hspace*{0.5cm}}% %-------END TABLES--------   In the document:  \begin{threeparttable}[!h] \centering \caption{Number of sample deletions by reason} \label{tab1} \begin{tabu}{X[.3,r]X} \toprule Number of respondents & \multicolumn{1}{c}{Reason for deletion}       \\  \midrule 77,934                & Number of respondents in original SOEP sample    \\ -23,690               & \TableIndent 1. Not in sample starting 2004\\  \cmidrule(r){1-1} 54,244                 &                                                \\  \addlinespace -52,673                & \TableIndent 2. Started first job before 2004   \\  \cmidrule(r){1-1} 1,571                 &                                                   \\ \addlinespace  -16                & \TableIndent 3. Risk data is not available     \\  \cmidrule(r){1-1} 1,555                 & Sample used for analysis                          \\  \addlinespace \bottomrule \end{tabu} \end{threeparttable}   I thought that I had my environments nested wrong, but all answers so far have tabu inside of threeparttable.


Mac not booting in OS X. Partition showing FFFFF-FFFF

I did the same thing as mentioned by the poster of  question and I am facing the same problem. My Mac is not booting in OS X and I am unable to find the startup disk also. I gave the same commands and found that the partition type is changed as OP's.


How do you scale textures in blender 2.8

In blender 2.8 I made a model of a door. I put a texture on the door mesh but it does not fit correctly. It needs scaling down. How do I scale it?


Metasploit ruby "bad interpreter: Permission denied"

When I'm typing in my terminal msfconsole I got something like this:  bash: /usr/bin/msfconsole: /usr/share/metasploit-framework/ruby: bad interpreter: Permission denied  ls -l /usr/share/metasploit-framework/ruby total 276 drwxr-xr-x  9 root root  4096 Aug 24 13:10 2.2.0 drwxr-xr-x 12 root root  4096 Aug 26 03:55 2.3.0 drwxr-xr-x  2 root root  4096 Aug 24 14:19 backward -rw-r--r--  1 root root  6252 Apr 14 08:16 changelog.gz -rw-r--r--  1 root root  3036 Apr 14 08:16 copyright -rw-r--r--  1 root root  4232 Apr 25 19:06 debug.h -rw-r--r--  1 root root  5785 Apr 25 19:06 defines.h -rw-r--r--  1 root root  1316 Jun 18 01:28 digest.h -rw-r--r--  1 root root 17849 Apr 25 19:06 encoding.h -rw-r--r--  1 root root 36172 Apr 25 19:06 intern.h -rw-r--r--  1 root root  5200 Apr 25 19:06 io.h -rw-r--r--  1 root root  4953 Apr 25 19:06 missing.h -rw-r--r--  1 root root   318 Apr 14 08:16 NEWS.Debian.gz -rw-r--r--  1 root root 37881 Apr 25 19:06 oniguruma.h -rw-r--r--  1 root root  1191 Apr 14 08:16 README.Debian -rw-r--r--  1 root root   777 Apr 25 19:06 regex.h -rw-r--r--  1 root root  1465 Apr 25 19:06 re.h -rw-r--r--  1 root root 69536 Apr 25 19:06 ruby.h -rw-r--r--  1 root root  5339 Apr 25 19:06 st.h -rw-r--r--  1 root root   374 Apr 25 19:06 subst.h -rw-r--r--  1 root root   996 Apr 25 19:06 thread.h -rw-r--r--  1 root root  1333 Apr 25 19:06 thread_native.h -rw-r--r--  1 root root  2050 Apr 25 19:06 util.h drwxr-xr-x  4 root root  4096 Aug 24 14:18 vendor_ruby -rw-r--r--  1 root root  1854 Apr 25 19:06 version.h -rw-r--r--  1 root root  1677 Apr 25 19:06 vm.h


Modular arithmetic. $(-1)^rr! \equiv 1 \pmod p$, then $(p-r-1)! \equiv -1 \pmod p$

Let $p$ be a prime number and $r$ an integer such that $1 \le r \lt p$. If $(-1)^rr! \equiv 1 \pmod p$, then $(p-r-1)! \equiv -1 \pmod p$  I know that $n$ is a prime if and only if $(n -2)! \equiv 1 \pmod n$ and Wilson’s theorem: $p$ is a prime if and only if $(p - 1)! \equiv -1 \pmod p$. Still I haven’t found the right relation between them.  I would appreciate some help. Thanks.


How to override Insufficient Privileges Error

Is there any way to gain access to the standard "Insufficient Privileges" page and edit/replace it with custom error?


Group of $r$ people at least three people have the same birthday?

What is the probability that in a randomly chosen group of $r$ people at least three people have the same birthday?   $\displaystyle 1- \frac{365\cdot364 \cdots(365-r+1)}{365^r}$   $\displaystyle \frac{365\cdot364         \cdots(365-r+1)}{365^r} +{r\choose 2}\cdot \frac{365\cdot364\cdot363 \cdots         (364-(r-2) +1)}{364^{r-2}}$  $\displaystyle 1- \frac{365\cdot364             \cdots(365-r+1)}{365^r} +{r\choose 2}\cdot \frac{365\cdot364\cdot363 \cdots (364-(r-2) +1)}{364^{r-2}}$  $\displaystyle\frac{365\cdot364 \cdots(365-r+1)}{365^r}                 $     My attempt :  (May be typo in option $(3)$ of question !)  $$P(\text{at least 3 persons have same birthday})$$  $$= 1 - \{P\text{(no one has same birthday) + P(any 2 have same birthday)\}}$$  So, option $(3)$ is true.     Can you explain it, please?   It  before,  but I'm not satisfied by explanation.


Show that $2222^ {5555} + 5555 ^ {2222}$ is divisible by $7$. I tried factorizing but it didnt lead to anything. Can divisibility rules be used? Any ideas please tell me.


I've just realised that the Quorum badge does not show up in "Choose which badge to track",    in any of the three cases:   You have made no progress at all; You have a Meta quetion with one vote (50% progress) You have been awarded it.     Is there any design reason for this?    Note that this question seems to me to be different from .


How can I revert a config file back to the originally installed version after I have edited it?

I want to revert a file in /etc/ back to its originally-installed form. I have edited the file since it was installed. How can I revert this config file? Apt is smart enough not to overwrite edited config files, so how do I tell it that I want it to do so?  For argument's sake, let's say that I want to revert the file /etc/foo.conf from the package foo.


Are there any other Parselmouths mentioned in canon, besides Harry, Tom and Salazar?

Tom Riddle says to Harry, that they are both probably the only Parselmouths in Hogwarts since Salazar Slytherin.  Parselmouth is said to be a rare gift, but is it really so rare? Are there really no mentions of other Parselmouths than those 3?


(Automatic Bike Project) amount of torque required to change gears?

I am planning to build an electronically controlled automatic bike transmission for my senior design project. I'm personally more of an electrical guy, so dealing with the mechanics is somewhat new to me. I would have loved to use an off-the-shelf electronic derailleur, but alas, they are too cost prohibitive (the school has allotted a budget of $115 per student and we're a group of two, so we have $230 to spend). So I'm going to need to make my own like several other people have done.  I am planning on using the bike's current derailleurs and replacing the hand shifters with motors of some sort to pull on the cables. Of course, we're going to need a certain amount of torque to shift up (and much less for shifting down) and a holding torque to ensure that we don't accidentally slip down a gear.   I have not bought a bike yet, I'm looking at a Diamondback bike that I found on Craigslist (it looks like a hybrid bike). So I'm wondering if there are any average measurements for the required torque.  And of course, I'm sure there are many people more experienced in bicycling than I am. So if you have a better solution, please feel free to shout it out. I'm all ears.


Noetherian prime ideals and Noetherian ring

If $R$ is a commutative ring, and for every $P$ a prime ideal of $R$, $P$ is a Noetherian $R$-module, show that $R$ is Noetherian.


Font size in text annotation when exporting QGIS layouts to PDF or JPEG?

When I try to export a map from the Layout Manager in QGIS, all the elements apart from the text annotation come through fine. These come through as tiny objects, with tiny font.  I could put labels on in the layout manager, rather than on the project window, but as far as I can see, there is no option for using the handy call-out boxes that are available in the main project window.


How can I ensure an angle valve points in the direction I want it to?

This may sound silly but after a few home improvement projects involving minor plumbing tasks (like changing faucets) this has always bothered me.  I'm going to talk about the specific example of an angle valve since it's the one I've faced more often, but this could apply to any kind of plumbing accessory that you twist on until its tight.  I've included an image below of the kind of thing I'm talking about in case the translation I googled is off.  In Europe at least, usually you have a shut-off valve like the one in the picture on every water point in the house. In my case, in the house I moved in, I had some very crappy ones with plastic handles that broke with time and didn't serve their purpose anymore (you couldn't use them to shut the water without using pliers)  When installing the replacement it bothered me that I could not get it tight and pointing to the direction more convenient to then connect it to the appliance/faucet.  Logic seems to dictate that it's however the ridges/groves align between the female point on the wall and the valve's male connection but it's weird for an amateur to see that such a detail would be left to luck or expecting that the female point on the wall was mounted with any intention regarding ridges or what will connect to it.  When I faced this, first I tried starting to twist at different points but found that they only engage at very specific points which makes sense and shows the same result (or same 2 results in some cases) no matter where you start. Then I thought just to tighten it to the maximum then go back enough until it's in the position I want it to be, but even when properly using Teflon tape around the grooves I've found that it needs to be absolutely tight to not have any sort of leaks.  Is there any trick to it?


Landau's argument for dependence of Lagrangian on magnitude of velocity

In chapter 1, of Landau-Lifshitz Mechanics' book, Landau through isotropy and homogeneity of space and homogeneity of time proves that the Lagrangian must depend of magnitude of velocity of the particle.  This seemed fine. But he didn't give a reason as to why it must depend of $|v|^2$ and not on some $|v|^n$ where $n\neq2$.


What should I do about questions that have a wrong preconception already in them

An example might be: "Why is the sky neon green?"  What should I do with such questions? Close as off-topic? Close as unclear? Downvote? Answer with (in this case) "It isn't, it's blue most of the time"?  I vaguely remember seeing a question about this but couldn't find it with a search, apologies if this has already been asked.


How to fix stepped diagonal lines happening in illustrator export

I am trying to save a logo file for a website from illustrator but when I view the image after export the diagonal lines are stepped and not sharp. It is a small file, 175px wide as this is what it needs to be for the website. Can anyone help me? I need these lines to be straight.


Feature request: Delete option for posts in SE Android app

Right now there is no option to delete my own answers and questions in SE Android app.


Add an object to an existing variable into the object

I have a little problem, I'm in this situation: I have a json that I parse with no problems with json_decode making an object, in this array I have various values, in particular I have an array called "message" then I want to add values to this $jsonObj->message for example:  $jsonObj->message->hello = 'example';   now I want to add another object to $jsonObj->message without removing other values then, what I want is:   $jsonObj->message->hello; // this is auto generated from the json   $jsonObj->message ADD $json2;   So I should have $jsonObj->message->somethingIntoJson2 and $jsonObj->message->hello too;  Thank you.


Prove that Space of Lipschitz continous functions is Banach space

Let $X$ be the vector space of Lipschitz continous functions, $[0, 1] \rightarrow \mathbb{R}$. For $x\in X$ set $$\Vert x \Vert_{Lip}=\vert x(0)\vert+sup_{s\neq t}\left\vert \frac{x(s)-x(t)}{s-t}\right\vert.$$   I need to prove:   $\Vert x \Vert_{\infty}\leq\Vert x \Vert_{Lip}$ for $x\in X.$ $\left ( X,\Vert.\Vert_{Lip} \right )$ is a Banach space.   I have tried to make an estimation of $\Vert x \Vert_{\infty}$ and compare it with $\Vert x \Vert_{Lip}$ but i could't reach that far. As to the Point 2. i know that you start with a Cauchy sequence and need to prove that it converges in $X.$ Unfortunately i couldnt come further either.  I will appreciate any comment or help. Thanks.


Bibdesk citing [?] instead of a proper citation

new to LaTeX and BibDesk. Hoping to somehow figure out how to get it to work!   I've entered all the required information into a bib file called Chapterbib.bib and saved it in the same folder as my file. In order to cite a source in my document, I copy the citation key into my document where I'd like to cite a source - however, rather than putting a citation in I simply get [?] after my sentence. I'm not sure what sort of packages or commands I should be using so any advice as to how to get moving from here would be much appreciated. Thank you for your help!


Intersection of an ellipsoid and plane in parametric form

I want to find the parametric equation of the ellipse in 3d space which is formed by the intersection of a known ellipsoid and a known plane. The ellipsoid has the Cartesian equation: $(x/a)^2+(y/b)^2+(z/a)^2=1$.  While the plane has the equation: $mx+ny+kz=0$. I have substituted one equation in the other but what I get is an elliptical cylinder since I had eliminated the $z$-components. How can I get the exact equation of the ellipse of intersection in parametric form?


Hey guys, I'm just trying to remove all the blue behind the logo I'm creating for our 7's tour group. I've never really used photoshop. As I just want the green image with the yellow outline. Thanks in advance.


In the last Harry Potter book, who kills these two characters?

I have always wondered this, and as today is the anniversary of the battle of Hogwarts, I think I will ask this:      Who killed Tonks and Lupin in the battle of Hogwarts?


Access VBA Error Getting Int() Value of Division

Don't know where I am missing, but the simple Access VBA snippet below returns 2 when I divide any floating numbers that the division equals 3.   Note: I have received the code with this Int() function, but if changes are necessary to achieve same result, I can change anything.  Sub RoundTest()      Dim a, b, c      a = 4.8     b = 1.6      c = Int(a / b)      MsgBox (c)  End Sub   Have any of you ever heard of something like this before? I tried on two different computers and get the same result. Maybe it is something with the Access compiler, or my code.


Can anyone help me solve this diophantine equation?

Find all integer solutions to $x^2 + 7 = 2^n$. I've done the case where n is an even integer but now I'm a little lost. Could anyone walk me through the solution?


Using the super class paramater for the subclass methods in the subclass

I trying to create a 2d shapes for my assignment. For that I will first creating an abstract Shape2d class. My assignment clearly indicates that I need to override the equals(Object o) method in the object class which will compare 2d shapes. I made the comparisons with comparing the shapes area and the perimeter disrespect to position in the 2d plane. But the problem here is, I cannot use the abstract methods of the Abstract class Shape2d. Since I need to override the method equals(Objcet o) I cannot convert into equals(Shape2d o). What I can I do with that ? There is my code in the below. /** This class is an abstract class and it is created for to be inherited specialized 2d shapes      *  @version 02.26.2021      */     public abstract class Shape2d      {         private int xLocation;         private int yLocation;              public Shape2d(int xLocation, int yLocation)         {             this.xLocation = xLocation;             this.yLocation = yLocation;         }              /** Getting the yLocation               *  @version 02.26.2021          *  @return          */         public int getYLocation()         {             return yLocation;         }              /** Getting the xLocation               *  @version 02.26.2021          *  @return          */         public int getXLocation()         {             return xLocation;         }              /** Abstact method which will be used for other 2d objects. Calculating the area of the 2d shape               *  @version 02.26.2021          *  @return          */         public abstract double calculateArea();              /** Abstact method which will be used for other 2d objects. Calculating the perimeter of the 2d shape                *  @version 02.26.2021          *  @return          */         public abstract double calculatePerimeter();              /** This method will calculate the distance of the two objects in absolute values.               *  @param anyShape          *  @return          */         public double calculatingDistance(Shape2d anyShape)         {             if(anyShape instanceof Shape2d)             {                 return Math.sqrt(Math.abs(Math.pow(yLocation - anyShape.yLocation,2) + Math.pow(xLocation - anyShape.xLocation, 2)));             }                  return -1;             }              @Override         /** This method is Overrided. It will return the Cordinates of the center (x,y)               *  @version 02.26.2021          */         public String toString()         {             return "Center Cordinates of the Shape is: (" + xLocation +"," + yLocation + ")\n";         }                   /** This method is overriding the equals method for finding out whether or not this shapes are the same          *  disrespect to its position in the                *  @version 02.26.2021          *  @param anyShape          *  @return          */         public boolean equals(Shape2d anyShape)         {             return calculateArea() == anyShape.calculateArea() && calculatePerimeter() == anyShape.calculatePerimeter();         }                        }


How can I reach chrome://plugins in Chrome 57 (or newer)?

In the past, Google Chrome allowed toggling of plugins (like enabling/disabling Flash) from the chrome://plugins URL. This page no longer exists (as of Chrome 57.0.2987.98).   What is the way to access Chrome plugins from this point onwards?


Is there an easy way to see that this simple recurrence is 9-periodic?

In a colloquium talk yesterday, Robert Bryant pointed out that for all initial values $a_0, a_1 \in \mathbb{R}$, the sequence generated by the recurrence relation $$ a_{n+1} = |a_n| - a_{n-1} $$ turns out to be periodic with period 9, i.e., $$ a_n = a_{n+9} = a_{n+18} = a_{n+27} = \cdots $$ This is an interesting and unexpected fact, especially when you consider that to directly prove the periodicity (by writing down expressions for $a_2, \dots, a_9$ in terms of $a_0, a_1$), you would have to prove the following monstrous identity: $$ a_0 = -\left| \left| a_1\right| -a_0\right| -\left| -\left| \left| \left| a_1\right| -a_0\right| -a_1\right| +\left| a_1\right| +\left| -\left| \left| a_1\right| -a_0\right| +\left| \left| \left| \left| a_1\right| -a_0\right| -a_1\right| -\left| a_1\right| +a_0\right| +a_1\right| -a_0\right| +\left| \left| \left| \left| a_1\right| -a_0\right| -a_1\right| -\left| a_1\right| +a_0\right| +\left| \left| \left| \left| a_1\right| -a_0\right| -a_1\right| +\left| \left| \left| a_1\right| -a_0\right| +\left| -\left| \left| \left| a_1\right| -a_0\right| -a_1\right| +\left| a_1\right| +\left| -\left| \left| a_1\right| -a_0\right| +\left| \left| \left| \left| a_1\right| -a_0\right| -a_1\right| -\left| a_1\right| +a_0\right| +a_1\right| -a_0\right| -\left| \left| \left| \left| a_1\right| -a_0\right| -a_1\right| -\left| a_1\right| +a_0\right| -a_1\right| -\left| a_1\right| -\left| -\left| \left| a_1\right| -a_0\right| +\left| \left| \left| \left| a_1\right| -a_0\right| -a_1\right| -\left| a_1\right| +a_0\right| +a_1\right| +a_0\right| +a_1 $$ Of course, a straightforward "brute-force" approach this problem would be to consider sequentially the cases $a_1 > a_0 > 0$, $a_0 > 0 > a_1$, etc. and show that the RHS whittles down to the LHS in each case. But due to the simplicity of the original recurrence relation, I wonder if there isn't a more elegant way (hopefully involving less casework) to see that this recurrence must be 9-periodic.


I recently installed ubuntu 14.04 on my home PC. Installation proceeded with no problems at all, but now I'm having trouble with the video drivers. The drive I need to install is SiS 671, v.7.14.10.5280, A01, I have the zip file downloaded, but is for windows.   When I go to configurations the drive used is a generic one, and no other option for choice.  I really need to install this driver, cause my screen isn't working very well with the generic one.  Clarification of the question: How to install SiS 671, v.7.14.10.5280, A01 driver on ubuntu 14.04?


A momentum equation validity for all particles?

An equation for momentum,  $$p = \gamma mv, \tag{1}$$ then for photon we get some indeterminate momentum which is 0/0.  But the formula $E=(m^2c^4+p^2c^2)^{1/2}$ gives for photon $$p=E/c .\tag{2}$$ And from equation $E=hc/\lambda$, we get an energy which is finite and then using (2) we get the momentum.  If equation (1) gives photon's momentum in an indeterminate form which is not true, then should (1) be termed valid for all particles?


I stupidly ran sudo chown -R carlos:carlos / and carlos is my user. This changed all files to be Carlos and I could not boot up again (because the root files were now owned by #1000) and I cant get sudo acess in live cd (because the owner of /usr was changed to my user). Can anyone help me? FYI I have mounted my hard drive.


cp: ./public.generic-pc.icns: Operation not permitted

On my MacOS Mojave: I'm trying to change the icon of an SMB Windows File server from the old CRT-BSOD icon to something newer like e.g. the NAS icons.  I'm fine with just using the NAS icon (the com.apple.xserve.icns) but I'm not allowed to replace the public.generic-pc.icns file in /System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/  I get an "Operation not permitted" error, even if I sudo cp ....


Let there be a sequence such that the distance between two consecutive terms converges to 0. Must this sequence converge?

I'm trying to solve the following analysis problem and I've developed a proof, I'm just not entirely sure if it's valid or not.   Let $\{a_n\}_n$ be a sequence such that $|a_n -a_{n+1}|\to 0$. Must $\{a_n\}_n$ converge? If so prove it, and if not, find a counterexample.  Proof:   Let $\epsilon > 0$. Since $|a_n -a_{n+1}| \to 0$, there exists $N\in \Bbb R$ such that$|a_n-a_{n+1}| \lt \frac {\epsilon}{m+n}$for all $n > N$. Then, for all $m,n > N$, we have      $$|a_m - a_n|= |a_m - a_{m-1} + a_{m-1} - a_{m-2} + ... + a_{n+1} - a_{n}| $$ $$\le |a_m - a_{m-1}| + |a_{m-1} - a_{m-2}|  + ... + |a_{n+1} - a_n|$$ $$ = \sum_{n}^{m - 1}{|a_{i+1}-a_{i}|} = \sum_{n}^{m - 1}{|a_{i}-a_{i+1}|}$$ $$ \lt \sum_n^{m-1} {\frac {\epsilon}{m+n}} = \frac{\epsilon\;(m+n)}{m+n}=\epsilon.$$ Therefore, the sequence is Cauchy and converges. $\Box$  Any help with checking/improving my proof would be greatly appreciated. Thank you!


As pointed out in a comment to the question this was about gfx.xrender.enabled. The answer can be found in the marked dupe, but it is easy to miss in all the noise talking about ssh and the X11 protocol. Direct link to answer:  My problem started happening about a month ago. I'm currently on Firefox 89.0.1. Up until this point, Firefox ran just fine over ssh -X. I'm running it from an Ubuntu machine (server) to an Ubuntu VM (client) and a different Ubuntu machine (server) to Windows 10 (client), both showing the same symptoms. It's not my hardware setup or -X as all machines are wired to a local gigabit switch and other applications (including Thunderbird) run just fine. They are a little slower than if I was running them on their own desktop, but perfectly usable. After it happened, Firefox is just .... slow. I'm using it with --no-remote and the actual window for Firefox appears in under a second. It then hangs there for about 2 minutes until the tabs become usable. The output in my ssh shell reads: $ firefox --no-remote & libGL error: No matching fbConfigs or visuals found libGL error: failed to load driver: swrast  (firefox:757486): GLib-GIO-CRITICAL **: 10:39:54.241: g_dbus_proxy_new: assertion 'G_IS_DBUS_CONNECTION (connection)' failed  (firefox:757486): GLib-GIO-CRITICAL **: 10:39:54.241: g_dbus_proxy_new: assertion 'G_IS_DBUS_CONNECTION (connection)' failed  (firefox:757486): GLib-GIO-CRITICAL **: 10:39:54.241: g_dbus_proxy_new: assertion 'G_IS_DBUS_CONNECTION (connection)' failed [GFX1-]: Failed GL context creation for WebRender: 0 [GFX1-]: FEATURE_FAILURE_WEBRENDER_INITIALIZE_UNSPECIFIED [GFX1-]: Failed to connect WebRenderBridgeChild. [GFX1-]: Fallback WR to SW-WR libGL error: No matching fbConfigs or visuals found libGL error: failed to load driver: swrast libGL error: No matching fbConfigs or visuals found libGL error: failed to load driver: swrast  but that doesn't look too different to what I had before. Can anyone please suggest anything that might speed it up? I'm not really looking for answers telling me that ssh -X is slow (it is, but it's acceptable to me on all other applications) or things to do with compression or cypher suites. My link is fine, except for Firefox.


Recently, on math.stackexchange.com, some people posted problems from an active contest. Is there a way I can "flag" the questions to get them deleted?


Errors CS5001 and CS0006 when compiling C# solution, compiler attempting to create .exe files for object projects

I have a Solution I'm building in C# that has projects A, B, and C, each of which contains a .cs file describing an object with a number of properties and a default constructor which sets the value of each property to some default value. I then have a number of other projects in the solution which use these objects, and so they each have references to A, B, and C so that they are able to use the objects defined by those projects.   When I try to compile, I first get the following error for each project when trying to build A, B, and C:  error CS5001: Program does not contain a static 'Main' method suitable for an entry point   Then, for each project that depends on A, B, and C, I get the following sequence of errors:  error CS0006: Metadata file 'C:\Users\...\A\bin\Debug\A.exe' could not be found error CS0006: Metadata file 'C:\Users\...\B\bin\Debug\B.exe' could not be found error CS0006: Metadata file 'C:\Users\...\C\bin\Debug\C.exe' could not be found   The start project for the solution is set to the GUI project that depends on A, B, and C. I cannot figure out why the compiler is attempting to create .exe files for A, B, and C, and why it wants to use those .exe files when building the other projects. Any insight would be appreciated, thank you.


Some special characters not displayed properly in a ǝɯɐuɹǝsn

For example,  when displayed in the Android app doesn't show the ǝ character properly  in the username:    This happens in their profile and on posts.  Android app version 1.0.18 on Samsung Galaxy S3 and Android version 4.1.2.


I'm trying to take a 12V wall wart supply down to 5V @ 0 to 500mA without using a prebuilt regulator. I was thinking to use a voltage divider setup but after doing calculations I would be using 2, 12 ohm resistors in series with the 5V breakout in between them, it sounds off to me.   How can I step down to 5V without sinking massive amounts of current in a resistive bridge or regulator?


Show that ${\Delta(\Gamma)}$ is the intersection of all maximal consistent ${\Sigma}$ containing ${\Gamma}$

In this question, we are dealing with predicate logic, where we have access to the deduction theorem, the soundness theorem, and the completeness theorem. The context of this question is the following:  First we say a set ${\Delta}$ of formulae is deductively closed iff ${ \Delta \vdash \sigma}$ implies that ${\sigma \in \Delta}$  So before this question, we have shown certain things to be true in our system mainly:  1- if ${\{ \Delta_i \}}$ are all deductively closed sets of formulae then so is ${\bigcap\limits_i \Delta_i}$  2- Any set ${\Gamma}$ of formulae is contained in a smallest deductively closed set ${\Delta(\Gamma)}$  3- We have established that ${\Delta(\Gamma) = \{ \phi : \Gamma \vdash \phi \}}$  4- We have shown that if ${\Sigma}$ is complete, then it is deductively closed.  (In our system, we have defined a complete set as a set that is consistent and for each sentence $\phi$ in a language $L$, exactly one of $\phi$ and $\neg \phi$ belongs to the set.  Also, a consistent set is a set that is only capable of deriving one of $\phi$ or $\neg \phi$, but not both.)  5- We aslo shown that if ${ \Delta(\Gamma) \cap \{ \phi, \neg \phi\} = \emptyset}$, then ${\Delta(\Gamma) \cup \{\phi \}}$ and ${  \Delta(\Gamma) \cup \{ \neg \phi \} }$ are both consistent.  Furthermore, we say that a set $\Sigma$ is maximal consistent for a language $L$ if $\Sigma$ is consistent and for any consistent set of sentences $\Sigma'$ in $L$ with $\Sigma \subseteq \Sigma'$, we have $\Sigma = \Sigma'$.  So to show the above question these are the only things that we have established and that we can use. I tried solving this question but It doesn't seem to work out especially that my solution was completely off, and I don't know what to do no, please help!!


I need some help in solving the following problem. We roll a fair die repeatedly until see the number $6$. Let $X$ be a random variable is a number of times we roll the die. Let $A$ be the event "The results of all rolls are even numbers". What is the value of $\mathbb{E}(X|A)$?


I have a Dell Latitude E5420 laptop which I upgraded from Ubuntu 13.10 to Ubuntu 14.04 a few days ago.  I can't help noticing a new annoying behaviour of the fan: it repeatedly gets loud every 1-2 seconds, it turns off, and then on again, for minutes and without any intensive-CPU process running.  Is there any fix for this?  Ok, so the temperature does seem to increase a little bit during these loud moments. It goes quickly from 50 to 60 degrees celsius, and then it cools off and goes back to 50.  It just had never happened so often before...  Noisy:  $ sensors acpitz-virtual-0 Adapter: Virtual device temp1:        +25.0°C  (crit = +107.0°C)  coretemp-isa-0000 Adapter: ISA adapter Physical id 0:  +55.0°C  (high = +80.0°C, crit = +85.0°C) Core 0:         +55.0°C  (high = +80.0°C, crit = +85.0°C) Core 1:         +54.0°C  (high = +80.0°C, crit = +85.0°C)  i8k-virtual-0 Adapter: Virtual device Right Fan:   121350 RPM CPU:          +59.0°C     Quiet:  $ sensors acpitz-virtual-0 Adapter: Virtual device temp1:        +25.0°C  (crit = +107.0°C)  coretemp-isa-0000 Adapter: ISA adapter Physical id 0:  +49.0°C  (high = +80.0°C, crit = +85.0°C) Core 0:         +51.0°C  (high = +80.0°C, crit = +85.0°C) Core 1:         +51.0°C  (high = +80.0°C, crit = +85.0°C)  i8k-virtual-0 Adapter: Virtual device Right Fan:      0 RPM CPU:          +50.0°C     , with a similar notebook model (Dell Latitude E6400), is having the exact same issue.  EDIT 2.   Now the fan has been turning itself on and off for minutes, but the temperature is  stable at 42 degrees Celsius:  $ sensors acpitz-virtual-0 Adapter: Virtual device temp1:        +25.0°C  (crit = +107.0°C)  coretemp-isa-0000 Adapter: ISA adapter Physical id 0:  +41.0°C  (high = +80.0°C, crit = +85.0°C) Core 0:         +40.0°C  (high = +80.0°C, crit = +85.0°C) Core 1:         +40.0°C  (high = +80.0°C, crit = +85.0°C)  i8k-virtual-0 Adapter: Virtual device Right Fan:   102210 RPM CPU:          +42.0°C    EDIT 3. I updated the Dell BIOS to the latest version (from 5 to 14), but to no avail.  If I run the fan test with fwts, one test fails and 5 succeed. I can't get a more verbose output, though...  $ fwts fan Running 1 tests, results appended to results.log Test: Simple fan tests.                                                        Test fan status.                                        5 passed, 1 failed                Load system, check CPU fan status.


Recover files of encrypted SD card after factory reset without decrypting the card

I own a Samsung ON 7 phone and I was using a class 10 Sandisk memory card which was encrypted by the device in the lock screen and security menu and with no other third party software. Now I have done factory reset on my phone and accidentally forgot to decrypt the SD card, now SD card is detectable and all the files are there and visible as well. but i can't open any file. What to do, please help !


Are there any libraries for drawing a neural network in Python?

I'd like to render a neural network in Python to make sure it is set up properly.  I'd like to verify that it has the correct # of nodes, correct edge configuration, and perhaps even correct edge weights after training.  I'd like to visually debug simple examples by printing them to a PNG/JPG but do not know any libraries that do this.  Is there a library for drawing a neural network for visual debugging?  (Such a library would of course make assumptions on the data types/structures - e.g., assuming the neural network comes from Theano, TensorFlow, or some other library.  I'm flexible on the assumptions made.)


Stupid number of duplicate items in "## new items in your Stack Exchange inbox" email

I was unable to visit Stack Exchange for around the past 48 hours (much to my consternation), so I got one of those emails telling me I have new inbox notifications.   The problem:    There are only 4 distinct items in the list, but 34 entries total (the link to  was repeated 15 times and the link to  was repeated 17 times).  If it matters, I'm a moderator on the site from which all these notifications originated.


Html code displayed when user entered simple quote on login page

i am facing an error whenever the user entered a simple quote(') in username or password fields when he tries to login..an HTML code is displayed and i can't fix it.  This is my login page  Login.php   require "init.php"; $user_name=$_POST['login_name']; $user_pass=$_POST['login_pass'];  $sql_query="select name,course_name,mark from user_info,Marks where user_info.username=Marks.student_username and username like '$user_name' and password like '$user_pass';"; $result = mysqli_query($con,$sql_query);  if(mysqli_num_rows($result)>0) {   $row=mysqli_fetch_assoc($result); $name=$row["name"]; $username=$row['username']; $course=$row['course_name']; $mark=$row['mark']; echo $name; } else {     echo "username or password incorrect"; }   Html code after login button pressed


My daughter and I both have apple phones and up until about 1 month ago she was always logged in on her device using my apple id.    I am trying to find out does this give her access to make any changes on my phone (not necessarily on purpose or even knowingly).  Specifically, under contacts, where my name is listed, right under my last name was listed a nick name that I didn't put there.  Could she have some how on her phone updated my either her name and it transferred over to my name because of the sharing issue?  Or if she was talking to Siri and she asked Siri to call her something, could that have updated to both her name and to mine?    I'm trying to figure out how it got there when I didn't put it there, or how to avoid that problem in the future.


Remove subfolders but keep files in windows for google photos

When you download photos using google takeout, it puts them in a ton of folders (606 for me). I want to get all of the 2000-ish photos from all of those folders and just put them in a single folder so I can then sort them myself into month-albums.   So my question is, how do I get rid of all the sub folders from a folder but keep the files?


Can somebody help me understanding the fouries series coefficients?  I know that if we have:  $$f(t) = \sum_{n=1}^N A_n \sin(2\pi nt + Ph_n) \tag{where $Ph_n$ = phase}$$  And because of the $\sin(a+b)$ formula: $$ f(t) = \sin(2\pi nt + Ph) = \sin(2\pi nt )\cos(Ph_n) + \cos(2\pi nt )\sin(Ph_n)$$ Then:  $$\sum_{n=1}^N A_n \sin(2\pi nt + Ph) = \sum_{n=1}^N (A_n\sin(2\pi nt )\cos(Ph_n) + A_n\cos(2\pi nt )\sin(Ph_n))$$ And by definition: $$a_n = A_n\cos(Ph_n)$$ $$b_n = A_n\sin(Ph_n)$$ Then:  $$f(t) = \sum_{n=1}^N A_n \sin(2\pi nt + Ph) = \sum_{n=1}^N (a_n\sin(2\pi nt ) + b_n\cos(2\pi nt ))$$ Where does the $A_n$ in the first formula come from? Could somebody explain me where does the $\frac{a_0}{2}$ in the formula below come from? $$f(x) = \frac{a_0}{2}+\sum_{n=1}^\infty (a_n \cos(nx) + b_n \sin(nx))$$  And the most important:  How can I proof the formulas for the $a_n$ and $b_n$ coefficients?  PLEASE, I'm searchinf for these answers for DAYS.


I'm getting this error when I try to reload Synaptic, I installed apps in terminal via ppa's I found on launchpad.net and dep files from other developer sites...  Could not download all repository indexes  The repository may no longer be available or could not be contacted because of network problems. If available an older version of the failed index will be used. Otherwise the repository will be ignored. Check your network connection and ensure the repository address in the preferences is correct.  Failed to fetch dl.google.com/linux/deb/dists/stable/Release  Unable to find expected entry 'non-free/binary-amd64/Packages' in Release file (Wrong sources.list entry or malformed file) Failed to fetch ppa.launchpad.net/apt-fast/stable/ubuntu/dists/trusty/main/source/Sources  404  Not Found Failed to fetch ppa.launchpad.net/apt-fast/stable/ubuntu/dists/trusty/main/binary-amd64/Packages  404  Not Found Failed to fetch ppa.launchpad.net/apt-fast/stable/ubuntu/dists/trusty/main/binary-i386/Packages  404  Not Found Failed to fetch ppa.launchpad.net/nanny/ppa/ubuntu/dists/trusty/main/source/Sources  404  Not Found Failed to fetch ppa.launchpad.net/nanny/ppa/ubuntu/dists/trusty/main/binary-amd64/Packages  404  Not Found Failed to fetch ppa.launchpad.net/nanny/ppa/ubuntu/dists/trusty/main/binary-i386/Packages  404  Not Found Failed to fetch ppa.launchpad.net/stebbins/handbrake-releases/ubuntu/dists/trusty/main/source/Sources  404  Not Found Failed to fetch ppa.launchpad.net/stebbins/handbrake-releases/ubuntu/dists/trusty/main/binary-amd64/Packages  404  Not Found Failed to fetch ppa.launchpad.net/stebbins/handbrake-releases/ubuntu/dists/trusty/main/binary-i386/Packages  404  Not Found Some index files failed to download. They have been ignored, or old ones used instead.   Someone suggested I edit /etc/apt/sources.listWhen I open it up all I see is the normal ubuntu ppa's


Latex how to make capital A without the middle bar?

have often seen in texts on Lie groups a capital A but without the middle bar but how to make such in Latex ?


How to prove that if $(ab,n)=1$ then, $(r,n)=1$?

Let $ab=nq+r$ where all variables represent integers with $0\leq r<n$. If $(ab,n)=1$ then how to prove that $(r,n)=1$? I need to prove this to help me understand the proof of Euler's theorem better.  I have been able to reason it out verbally but I want to prove it rigorously using equations. If $d=(r,n)$ then $d|r$ and $d|n$. Therefore $d|(nq+r)$. Therefore $d|ab$. But $(ab,n)=1$. Since $d|n$ and $d|ab$, hence $d=1$. Therefore $(r,n)=1$. I cannot figure out how to frame the equations to express this. Please help.


Decomposition of vector space to produce nilpotent and invertible transformations

Let $V$ be a finite-dimensional vector space over a field $K$. Let $T$ be a linear operator on $V$. Prove that there exists a unique sum $V=V_{0}+V_{1}$ such $T(V_{0}) \subseteq V_{0}$, $T(V_{1}) \subseteq V_{1}$, $T|_{V_{0}}$ is nilpotent, and $T|_{V_{1}}$ is invertible.   Is this exercise related to invariant spaces and direct sums? I was reading the theory, and I can't see how start the problem.


The below bug doesn't always happen, but does most of the time. Steps to reproduce:  Go to any review queue Post a comment Edit the comment Click Save Edits  Result:  Obviously the red box above is the annoying bug...  :-)


How method parameters are passed in Java?

Sorry for my some stupid question but I've learned that parameters in Java passed by value. If I write code like this, i get 69, not 690 because in this method I changed the copy of variable num. public class Main {     public static void main(String[] args)     {         int num = 69;         mystery(num);         System.out.println(num); //69     }     public static void mystery(int num)     {         num *= 10;     }  } But in this example values of my array are changed!!! And I don't understand why, cause I thought parameters passed by value!! public class Main {     public static void main(String[] args)     {         int[] a = {1,2,3,4,5};         mystery2(a);         for(int e : a)         {             System.out.print(e + " "); // 10 20 30 40 50         }     }     public static void mystery2(int[] array)     {         for(int i = 0; i < array.length; i++)         {           array[i] *= 10;         }      } }


START where both path and filename have spaces

START /high /d "./files" "Program Name.exe"     This doesn't work, it works if "Program Name" wasn't in quotation marks, but in this scenario i don't have control over the file name and where the batch file gets executed. How would i solve this using Batch?


R glmnet package: why is elasticnet parametrized like that?

The documentation for glmnet in R  states that it solves the following minimization problem:    Why did the authors choose to parametrize $\alpha$ in such a way that $\alpha=\frac{1}{3}$ corresponds to the elastic-net parameter that will lend equal weight to the $L_1$ and $L_2$ parameter, rather than the seemingly natural choice of $\alpha=\frac{1}{2}$? Is there a reason that they added the extra factor of $\frac{1}{2}$ to the $L_2$ penalty?


Why do DNGs only show in low resolution on Google Photos?

Through my NAS at home I store and backup all my photos on Google Drive. These photos also show up on Google Photos. I use Lightroom and convert all photos to DNG when copying to my NAS.  When I look at the photos in Google Photos the image is rather small. Clicking the (i) info button tells me the image has a resolution of 1024x680, file size 9.8 MB and a MP of 0.7. This is probably just a preview or thumbnail of some sort, but how do I view the image in larger resolutions in Google Photos?


I'm getting the below data which is a jpeg image in response body. Below is a screen shot of the response.      When i do type of res._body, it is a string. How can i convert it base64 string so I can render the image in browser, or is there an easier/another way to solve this. This is a part of angular app I'm building.


Can anyone give me the pattern of the regex to get all the local images ONLY. :( I'm using the code below but it includes the image links.    Regex rgx = new Regex("[^\\/:*?\"<>|]+\\.(?i)(jpg|png|gif|bmp)", RegexOptions.IgnoreCase);   input:   http://dl9.glitter-graphics.net/pub/846/846279rr8zhg26y6.gif  images/strawberries.jpg   output:   846279rr8zhg26y6.gif  strawberries.jpg    I don't want the 846279rr8zhg26y6.gif


Why is it so hard to find the roots of polynomial equations?

The question that follows was inspired by  question:  When trying to solve for the roots of a polynomial equation, the quadratic formula is much more simple than the cubic formula and the cubic formula is much more simple than the quartic formula.    That the general solutions to various polynomial equations are so complex and difficult to derive seems to suggest a fundamental limitation in the problem solving capabilities of the mathematical machinery. Does this intuition of mine make any sense? What should I make of it? Why is it that with each successive degree in a polynomial equation, the solution becomes so much more complex? Can I gain some intuition about what makes finding the roots so hard? According to the : "there is no general algebraic solution—that is, solution in radicals— to polynomial equations of degree five or higher." What is so special about the quintic that makes it the cut-off for finding a general algebraic solution?


VS code application- Unable to authorize an org or run any commands on the terminal

I am facing issue with my vs code application. Not able to run any commands in the terminal except sfdx. Unable to authorize org(Getting error- ended with exit code 127). I googled and tried most workarounds like re installing vs code application enter image description herecode, salesforce CLI, checked with IT team to see if it is firewall or proxy issue. But they confirmed it is not proxy issue . Not sure what is the exact issue here. Can anybody please assist me. sfdx update is also not working. I have attached 2 screenshots of the errors. It would be great if anyone has any inputs on this. When I try to authorize an org it redirects to browser , but when I enter my credentials getting localhost:1717 error as attached in the image. sfdx update : throws sfdx-cli: Updating CLI... ! »   Error: Channel "stable" not found. Please assist. Regards, Madhura


I have 2 messages which have been encrypted using the same pad. I know that if i xor these 2 messages together the key falls out. I am confused in how to figure out what the 2 messages are from the combined xor of the two. How do I go about decoding the 2 messages?  I am aware of crib dragging, but I don't know how to figure out which message the crib belongs to.  Note: the key(pad) used is a random sequence  Links to or Concrete examples of how to implement a solution would be really helpful.


The ♦ character is formatted to look like the moderator diamond on the Android app

Whilst using the SE Android application last night I noticed I had an upvote on  I wrote a while back. This answer features the ♦ character which is the same character used to distinguish moderators. Rather than treating this as a regular ♦ character, it gives it the same larger, orange style that the moderator diamonds have, both in text and within a code block:      This affects the listing screen as well as question titles:


Set CRS to numpy array with no geographical data using rasterio

I have 1 dimension numpy array that has no geographical information. The numpy array was originally satellite image that I have manipulated in order to get this 1 dimension array. I have the crs and transform of this array. However, until now, in order to have geographic data on this array I had to write it as tiff and only then I could get back the geographical data and do things such as crop the raster and more. I know there is option to reproject an array with no geographical data, as mentioned  . I have tried to do this with my data as following, based on the doc: src_shape = (886, 1138) rows, cols = (886, 1138) d = 1.0/240 # decimal degrees per pixel # The following is equivalent to # A(d, 0, -cols*d/2, 0, -d, rows*d/2). src_transform = A.translation(-cols*d/2, rows*d/2) * A.scale(d, -d) src_crs = {'init': 'EPSG:4326'} source = img_pred      dst_shape = (886, 1138)  dst_transform = rasterio.transform.from_bounds(*bbox, width= bbox_size[1], height= bbox_size[0]) # this gets the transform which is in this case : Affine(0.00011618510158013974, 0.0, -44.75374, 0.0, -7.050087873462236e-05, -6.80845)    dst_crs = rasterio.crs.CRS.from_dict(init='epsg:4326') destination = np.zeros(dst_shape, np.uint8)   reproject(     img_pred,     destination,     src_transform=src_transform,     src_crs=src_crs,     dst_transform=dst_transform,     dst_crs=dst_crs,     resampling=Resampling.nearest)  Then I get new array with values 0:  So my question is : how do I get my array with the values reprojected correctly? I assume that the problem might be in the definition of the original CRS, (src_crs), as my numpy array has no crs at all, but not sure if this is the reason.


Drawing Roman laurel leaves (SPQR) in TikZ

I was trying to get the symbol of the old .  I'm actually interested in the laurel leaves, and not so much in the banner per se.  What I would like to have is something like this (in Tikz, as oppose to simply \includegraphics).  With the possibility to change the stylish A to any other simple roman letter.    I'm a complete newbie with TikZ, and even though I know this question sounds like do this for me, I would really appreciate if someone could at least throw in an sketch where to start.


possibility, importance and order-optimality of algorithms

Evaluate below claims of the problems and their algorithms in terms of possibility, importance and order-optimality.   Problem A has worst-case lower bound $\Omega(n^{2})$ and there is an algorithm with $W(n) \in \mathcal{O}(n)$. Problem B has sharp worst-case lower bound $\Omega(n^{2})$ and there is an algorithm with $W(n) \in \mathcal{O}(n)$.


Strange temporary network outage in Linux

I'm facing a very annoying problem that I noticed a week from now and for which I can't find an answer: my network suddenly stops responding, usually coming back exactly 25 seconds later. I was using kernel 3.10.4 and now migrated to 3.11-rc4 to see if something changed, but no, the behavior is the same. And since it is a hard to spot problem due to the fact usual web surfing is in "bursts" and the outage is completely random, I can't really tell this problem was present in a previous kernel as well (I always use custom but unpatched kernels from kernel.org, all compiled by myself)  I can't tell the kernel is the culprit either, but I can say there are no clues on the system logs (I checked both /var/log/syslog and /var/log/messages and there is nothing unusual there) and that hardware doesn't seem at fault, for the problem shows up using either one of my network cards:  lspci output:  02:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5751 Gigabit Ethernet PCI Express (rev 01) 04:00.0 Ethernet controller: 3Com Corporation 3c905B 100BaseTX [Cyclone] (rev 30)   and I already tried to exchange the ethernet switch ports and still no one else where I work has a problem except me (although we use similar machines, I'm the only one using Linux, so I had to take some infamous jokes about it as well... hehe).  I ran up wireshark on my machine and left it continuously pinging our gateway and another machine on the same network segment. Then, at the first sign of network malfunction I would check it and verify the gateway stopped responding pings, but the other machine was still there responding normally. Some other times is the other machine which stops responding and the gateway is fine, and some other times both stop responding. I don't know what else to do, so I'd like some help or tips on how to further debug this, since the system logs are completely normal.  I have my kernel config file and a capture file from wireshark showing the situation. I can post here or at some pastebin site in case anyone finds it useful to understand the case, just please let me know the detail level I should use (I guess the packet level without the raw data would be enough).


My wife wants a 4th baby, but I don't.  We have been talking about it for the last few days (talking strongly).   I have raised points such as:   We will get less time to spend with our current kids. The age gap between the first and the last will be too wide. It will cost more money. She will be out of work longer. We will need a bigger house. And we don't even have our own house yet (we are still renting). We will have to start again. Sleepless nights, nappies, feeding, new cot, car seat, etc etc.   She says:   She feels like she is missing something. She has always wanted a large family. Things will be the same regardless of having 3, or 4 kids. She agrees that money will be tighter, but wants to push through it.   Our current kids are 9 months, 2 years, and 4 years. We are young married couple (25), and I have a fairly decent job.  What would be the pros and cons of having another child?   How can we rationally talk to the other about having/or not having another child?  And what should we do if we cannot agree?


Cronjob doesn't run. Similar cronjob does run. Issue with Env Vars??? Fedora involved. psql involved

I have cronjobs like so  * * * * * /usr/bin/psql -U usename dbname -c "select usename, now(), pg_terminate_backend(pid) from pg_stat_activity where state like 'idle%' and (now() - query_start) > interval '2 hour';" &> /home/fedora/terminate_backend.log * * * * * /usr/bin/psql -U usename dbname -c "vacuum analyze;" &> /home/fedora/vacuum.log   The second is running and producing the requested, albeit useless, log. The above does not create a log and I have reason to believe that it is not running.   I've tried adding /usr/bin/echo "DUMB" > /home/fedora/dumb.log; in front and still nothing appears.   It looks like so  * * * * * /usr/bin/echo "DUMB" > /home/fedora/dumb.log; /usr/bin/psql -U usename dbname -c "select usename, now(), pg_terminate_backend(pid) from pg_stat_activity where state like 'idle%' and (now() - query_start) > interval '2 hour';" &> /home/fedora/terminate_backend.log   Any help is appreciated. Might it have something to do with env vars? If looked in env and tried adding the host 127.0.0.1, Nothing. And btw, the vacuum one works, so...


Why geom_density is showing me values higher than 1 in the density plot? How to change it into fraction?    And my code used to generate the plot  ggplot(data = input2, aes(x = r.close)) +   geom_density(aes(y = ..density.., fill = `Próba`), alpha = 0.3, stat = "density", position = "identity") +    xlab("y") + ylab("density") +   theme_bw() +   theme(plot.title=element_text(size = rel(1.6), face = "bold"),         legend.position = "bottom",         legend.background = element_rect(colour = "gray"),         legend.key = element_rect(fill = "gray90"),         axis.title = element_text(face = "bold", size = 13))


Are the insides of LCD monitors dangerous?

I have an LCD monitor that is cracked. So far nothing leaks out but if something starts leaking should I be concerned?   I have searched and read everything from:     It is safe to be around and handle just don't eat it.   to     It is toxic and should be avoided!   So I ask which is it? Should I be concerned if I see leakage?


Square root of a squared number: $\sqrt{a^2} = a \in \mathbb R$?

True or False  $$a\in \mathbb R\implies \sqrt{a^2} = a$$   a positive or negative, will always be equal to a, so for me it is true, but the teacher says that the expression is false, but I can not understand why?


Let $A, B, C$ be some complex matrices. If $AB - BA = C$ and $AC = CA$, then $C^k = 0$ for some $k$.

Let $A, B, C$ be some complex matrices. Suppose that $AB - BA = C$ and $AC = CA$. Prove that: $C^k = 0$ for some $k$.   It is an exercise in the section of "Jordan Canonical Form of Nilpotent Transforms". But I am not sure how to prove the question. Could anyone give me a hint?


My USB has my stuff in it but it says it's empty

My USB was working 100% fine before I went to college yesterday. I added some new files to it, took it to school, plugged it into my teacher's computer, and nothing shows up. It says it's empty. I tried it with a different computer to see if it was just the teacher's PC. I plugged it in and I got the same thing.  How do I get my files back? Most of my stuff is on there and I would like them back as soon as possible.


Why do we define the convolution?  Why is convolution useful?  What is the purpose of the geometry of convolution of two functions in plane? Can we draw the convolution of two functions without compute the integration?  What is idea of definition of convolution?  What is relation between convolution and probibility?  I have already read


I'm looking to get rigorous definitions on which to base the important quantities in classical mechanics.  To me a "rigorous" physical definition is an operational definition -- that is one in which we define how to measure the quantity over the course of an experiment -- or a definition in terms of other quantities which are operationally defined.  Time can be measured (at least in classical theory) arbitrarily well with clocks.  Whether or not we can actually build a clock with the necessary accuracy is not important for this definition as long as we can conceive of one being built.  Position can be measured arbitrarily well with measuring sticks.  Using these two quantities above we could conceive of strategically placing an array of measuring sticks and clocks (that is building a reference frame from them) so as to entirely measure the motion -- position, velocity, acceleration, etc as a function of time -- of any object we care to.  Now I turn my attention to the most important equation in Newtonian mechanics: $F=ma$ (or $F=\dot p$ it doesn't really matter in this case).  For this equation to make any physical sense we need to be able to measure the mass and/ or force (and/ or momentum) of an object during any experiment arbitrarily well.  How can we define force or mass (or momentum) in such a way that in the midst of some complicated motion -- possibly involving losing/gaining mass, etc -- we can still be certain that we can measure values for these quantities?  One note on this: I would prefer not to assume the equivalence principle as a way of measuring mass.  Let's just pretend that inertia mass and gravitational mass are not the same because, as far as I can tell, in classical mechanics there is no strong reason to believe the equivalence principle holds based solely on Newton's laws (and other equally important "first principles" like the conservation laws).  Of course, there's empirical evidence, but again let's just ignore this for now and see if we can find another way of measuring mass (or force or momentum or kinetic energy or any other thing which as allow us to obtain a measurement of mass indirectly).    EDIT: This will be a response to the  (admittedly a similar question) detailing why I find the answers therein unsatisfactory.  My hope is that either someone can give a new answer or can assuage my uneasiness about one or more of those answers to the linked question.  The top answer is by joshphysics.  The part about forces (and masses) is his statement of the third law: " If any two objects are being observed in a local inertial frame, then their accelerations will be opposite in direction, and the ratio of their accelerations will be constant."  Here he implicitly assumes that two objects in an inertial frame will be accelerating.  So I think he just forgot to add that there must also be so interaction (force) between the two objects.  If we assume that there is an interaction between the two objects then this is just Newton's regular old third law (pretty much).  However, this definition only provides a means of measuring mass if the accelerations of the two bodies are completely due to the single interaction between the two objects.  I'm not entirely sure I understand his second law and so let's move on.  The second answer is by Cleonis.  His second law is the standard second law.  Cleonis claims that he's defining force and mass but he doesn't (well he does seem to imply that given a known force that mass is just a constant of proportionality in the last sentence of his third-to-last paragraph before the additional remarks -- but without a way of measuring force, it's not useful) -- so that's a bit disappointing.  Constantine then defines force as the time derivative of momentum.  Even if we leave force as a primitive we still need a method of measuring the mass of an object in any given system.  His method of defining it in a system of two particles doesn't work if we have more than two particles so it has a very limited applicability.


SHA-256 is a well know hash function that creates digests of 256 bits. This means that the size of the digest space is 2^256 (or at least it should be), ie, the range of the digest space is:     from 0x 00 00 00 ... 00 00 00 to 0x FF FF FF ... FF FF FF   Question However, is there any kind of limitation in the SHA-256 algorithm that would not allow a specific range of digests?    For example: 0x 00 00 00 ... 00 00 00 and 0x FF FF FF ... FF FF FF are two possible digests for SHA-256 or it is impossible to exist a message that would hash into those values?


A Systematic Way to find Counter Examples? via Linear Algebra

So I had a test today, and one of the questions was:   "Give an example of a set, S contained in $R^3$ that is closed under scalar multiplication but isn't closed under addition"  And I was just wondering -- is there a systematic way to go about this rather than search for examples? Perhaps some sort of algebraic way to create such a set that satisfies these conditions without any further thought?


Tomorrow morning I want to try a soft-boiled ostrich egg in my sous-vide cooker at a temperature of 65°C. Does somebody know how long the egg has to stay in the sous-vide cooker? I've found an online calculator which says 1h40min. Do you think that's enough time? I'am a little bit skeptical. :D


Renting a car from Detroit to Tennessee or Florida

I'm in Michigan and I'd like to get to Tennessee or Florida. My idea is to go by car but when I see what the rentals cost (one way is immensely more expensive and I won't be going back north myself), It feels kind of pricey.  Is there a cheaper option? I've googled to see if I can find a web site with one way cars (someone who wants his delivered, for instance) but haven't been lucky with that.  Suggestions?


For a project, I need to simulate from a joint distribution with both continuous and discrete variables that are dependent. The conditional distribution of any variable given the rest is known. I decided to simulate with the help of Gibbs sampling. My question is:  Is it possible to simulate from a joint distribution containing both continuous and discrete variable with Gibbs sampling?


Sometimes whenever I write a program in Linux and it crashes due to a bug of some sort, it will become an uninterruptible process and continue running forever until I restart my computer (even if I log out).  My questions are:   What causes a process to become uninterruptible? How do I stop that from happening? This is probably a dumb question, but is there any way to interrupt it without restarting my computer?


How to stop people from using my domain to send spam?

I receive Mailer Daemon messages saying certain emails fail. My domain is itaccess.org which is administered by Google apps. Is there any way I can identify who is sending emails from my domain, and how they are doing it without me creating an account for them?  Delivered-To: 7e949ba@itaccess.org Received: by 10.142.152.34 with SMTP id z34csp12042wfd;         Wed, 8 Aug 2012 07:12:46 -0700 (PDT) Received: by 10.152.112.34 with SMTP id in2mr18229790lab.6.1344435165782;         Wed, 08 Aug 2012 07:12:45 -0700 (PDT) Return-Path: <whao@www20.aname.net> Received: from smtp-gw.fsdata.se (smtp-gw.fsdata.se. [195.35.82.145])         by mx.google.com with ESMTP id b9si24888989lbg.77.2012.08.08.07.12.44;         Wed, 08 Aug 2012 07:12:45 -0700 (PDT) Received-SPF: neutral (google.com: 195.35.82.145 is neither permitted nor denied by best guess record for domain of whao@www20.aname.net) client-ip=195.35.82.145; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.35.82.145 is neither permitted nor denied by best guess record for domain of whao@www20.aname.net) smtp.mail=whao@www20.aname.net Received: from www20.aname.net (www20.aname.net [89.221.250.20])     by smtp-gw.fsdata.se (8.14.3/8.13.8) with ESMTP id q78EChia020085     for <7E949BA@itaccess.org>; Wed, 8 Aug 2012 16:12:43 +0200 Received: from www20.aname.net (localhost [127.0.0.1])     by www20.aname.net (8.14.3/8.14.3) with ESMTP id q78ECgQ1013882     for <7E949BA@itaccess.org>; Wed, 8 Aug 2012 16:12:42 +0200 Received: (from whao@localhost)     by www20.aname.net (8.14.3/8.12.0/Submit) id q78ECgKn013879;     Wed, 8 Aug 2012 16:12:42 +0200 Date: Wed, 8 Aug 2012 16:12:42 +0200 Message-Id: <201208081412.q78ECgKn013879@www20.aname.net> To: 7E949BA@itaccess.org References: <20120808171231.CAC5128A79D815BC08430@USER-PC> In-Reply-To: <20120808171231.CAC5128A79D815BC08430@USER-PC> X-Loop: whao@whao.se From: MAILER-DAEMON@whao.se Subject: whao.se:  kontot avstängt - account closed X-FS-SpamAssassinScore: 1.8 X-FS-SpamAssassinRules: ALL_TRUSTED,DCC_CHECK,FRT_CONTACT,SUBJECT_NEEDS_ENCODING      Detta är ett automatiskt svar från F S Data - http://www.fsdata.se      Kontot för domänen whao.se är tillsvidare avstängt.     För mer information, kontakta info@fsdata.se      Mvh,     /F S Data      -----    This is an automatic reply from F S Data - http://www.fsdata.se    The domain account "whao.se" is closed.   For further information, please contact info@fsdata.se    Best regards,   /F S Data


save new data to wp_options non-post form

I have a form on my front-page. It sends the entered address to Google API and returns the JSON to wp_options. That works fine. I am using update_option to do that, so it rewrites the meta_key each time. How would I go about having each address entered remain?    $address = esc_html( $_POST['address'] );    //assign JSON object to var using  geocodeing function('address') input    $address_results = gmap_geocode($address);    // transfer data to options array   $options['py_name'] = $py_username;   $options['address'] = $address;   $options['coords']  = $address_results;    // create and name the option_name and set fields with $options array   update_option( 'row_name', $options );


I was looking for an answer to this question for some days now:     Find a function f such that $f(f(x))=-x$   Please help, thank you!


Is the size of the universe directly related to its temperature?

The universe was at its hottest when it was at its smallest. As the universe expands, it gets cooler.   Is the expansion of the universe the direct cause the cooling?  I suppose it would be more clear to me if someone defined the meaning of 'temperature'.


In linear regression, any intuitive explanation why duplicating samples will reduce coefficients' std-dev?

I read the explanation by Ocram  about how to calculate the stddev of coefficients in linear regression.  I also run experiment with my sample data. I have test1 which contains 1000 samples; I then created   test2 = pandas.concat([test1, test1])   and run the same regression again. It is true that the standard deviation of each coefficient ($\beta$) decreased.   However, I cannot visually think about this behavior. Can anyone provide an intuitive visual explanation why the stddev goes down when I duplicate my samples?


After following the instructions in INSTALL.W64 I have two problems:   The code is still written to the "out32" folder. I need to be able to link to both 32-bit and 64-bit versions of the library on my workstation, so I don't want the 64-bit versions to clobber the 32-bit libs. The output is still 32-bit! This means that I get "unresolved external symbol" errors when trying to link to the libraries from an x64 app.


We know that Naruto's parents died right after his birth, and by the time he was in the Academy he was living alone. However, there must have been a period of time when he was being raised by someone, because babies can't take care of themselves. Is it ever said who raised him for that initial time or where he lived?


Find all instances on a 24 hour analog clock where if the hour and minute hands are interchanged we get a valid time.    Solution:  Let the position of the hour and minute hands be measured clockwise in degrees from the vertical.  Let:       X  =  position of hour hand    24X  =  position of minute hand  (mod 360)     After interchanging the hour and minute hands:    24X  =  position of hour hand    (mod 360)    576X  =  position of minute hand  (mod 360)  =  X    We seek all solutions to:       X  =  576X (mod 360)       0  =  575X (mod 360)       X  =  (360/575)N; N  =  0, 1, 2, …, 574


If $\emptyset$ denotes the empty set, what is $ \langle \emptyset \rangle$ in an group?

If  $\emptyset$ denotes the  empty set, what is $\langle \emptyset \rangle$ in a group?  Would it just be $\emptyset$? or none?


i need to convert png files to tiff. Is there an easy way to do so in Ubuntu 14.04? Thanks!


I ask this as I am confused about empty sets. I assume there is some formalisation past 'a collection of objects'. As then the empty set doesn't really make sense. Dealing with the empty set all the time in mathematics, I have become very comfortable with its manipulation. But upon trying to explain the axiom of choice to an undergrad philosophy student, he had a lot of issues with the concept of an empty set as a whole, making me question it myself.   Even if included as an axiom, what justifies its existence. The axiom of choice does seem very obvious when you are a person very used to manipulating the empty set, but if not it has little to no intuitive understanding.


$X\sim\operatorname{Poisson}(λ_1)$, $Y\sim\operatorname{Poisson}(λ_2)$ are independent how find the derivative of the distribution for $X | (X+Y=u)$?

I want to compute the derivative of the distribution of $X|(X+Y=u)$.


In Game of Thrones S08E06, we see        Arya deciding to conclude her character arc in Westeros     and set sail to West of Westeros. Jon asks her what is there in West of Westeros & she replies with something like Nobody knows?     Do we know what lies beyond West of Westeros? Do we have anything to go by from A Song of Ice and Fire Or from A World of Ice and Fire or other supplementary books from GRRM?


Using python to set object shading to 'smooth'

So I wish to create and object and set it's shading to 'smooth' using python. It seems simple enough but after trying every method I could find on the internet none of them worked for me. Here's a short example script where the object needs to have smooth shading:  import bpy from mathutils import Vector  verts = [(0,0,0),(0,5,0),(0.25,5,0),(0.25,0,0),(0,0,5),(0,5,5),(0.25,5,5),(0.25,0,5)] faces = [(0,1,2,3), (4,5,6,7), (0,4,5,1), (1,5,6,2), (2,6,7,3), (3,7,4,0)]  grat1mesh = bpy.data.meshes.new("grat1") grat1obj = bpy.data.objects.new("grat1", grat1mesh) grat1obj.location = (5, -5, 0) bpy.context.scene.objects.link(grat1obj) grat1mesh.from_pydata(verts,[],faces) grat1mesh.update(calc_edges=True)  grat2obj = grat1obj.copy() grat2obj.data = grat1mesh.copy() bpy.context.scene.objects.link(grat2obj) grat2obj.location += Vector((-0.125, 1.25, 1.25)) grat2obj.scale = (2, 0.5, 0.5)  bm = grat1obj.modifiers.new("Chop", 'BOOLEAN') bm.object = grat2obj bm.operation = 'DIFFERENCE' bpy.context.scene.objects.active = grat1obj bpy.ops.object.modifier_apply(modifier=bm.name) bpy.context.scene.objects.unlink(grat2obj)   I found this online and tried to place it at the end of the script:  smoothings = [] smoothings.append(face.use_smooth) me_ob.faces.foreach_set("use_smooth", smoothings)   However this just returned an error on the second line, perhaps as it was from an older website. Obviously using a simple bpy.ops.object.shade_smooth() didn't work and I'm kind of stumped as of what to do here!


Let $a,b,c\in\mathbb Z$. Then   $$ \gcd(a,b)=\gcd(a,c)=1\implies\gcd(a,bc)=1. $$   I tried using Bezout's Lemma, that states: if $a$ and $b$ are relatively prime, then $a\mid bc\implies a\mid c$.  This means in our case that $a\mid bc\implies a\mid c\ \land\ a\mid b$.  Is this the right approach? How to continue from here?  EDIT  Can I conclude from Bezout's lemma, that in our case, if a number divides $bc$, that is divides both $a$ and $b$? The reverse holds also. So the common divisors of $a$ and $bc$ are the same are the common divisors of $a$ and $b$, and $a$ and $c$?


I'm trying the next code:  \documentclass[pdftex,spanish]{article} \usepackage{babel} \usepackage{tikz}  \begin{document}  Simple arrow:   \begin{tikzpicture}     \draw[->] (-1.5,0) -- (1.5,0); \end{tikzpicture}  \end{document}   but it doesn't work. It throws the errors:    ! Argument of \language@active@arg> has an extra }. ! Paragraph ended before \language@active@arg> was complete.<to be read again>\par \draw[->]   What can I do if it works right without the babel package?


How to turn on bitlocker on 4 TB USB HDD?

When trying to turn on Bitlocker on an external 4 TB USB HDD using Windows 7, there's error A device attached to the system is not functioning. in a rather unhelpful dialog, as shown below:    Now according to , there are a few solutions, but the answers aren't very detailed. First of all, the solution in  (uninstall ) is unlikely to work I suppose, because this is external drive and uninstalling that would disable using Bitlocker on it completely. And then answers lack an exact way to format the drive to the maximum capacity, if that's the only way on external drive. So I'm looking for a succinct answer to these:   Does uninstalling  and then reinstalling it later work or not, with external drives? What's the exact command/method to format the drive to maximum working capacity? Other known-to-work ways to enable Bitlocker on the drive, like acquiring a Win8 PC to do it?


I have a table with three points in it and I want to create a line from them using PostGIS.    when I try to create a line from this geometry using:  select id,         st_makeline(geom order by id desc) as geom  from public."point_table" group by id;   I get null geometery    What am I doing incorrectly?  PostGIS version 2.2.1 PostgreSQL version 9.5.1


How to restart a video card driver in Windows 7?

Some times my video card driver (Intel GMA X4500HD) crashes and gets restarted automatically. But more often (almost every time I watch a flash-powered online video for a period of time) it just gets slower and slower and extremely slow until I restart my computer. This looks like a resource leak in the video driver code and I'd like to try restarting it alone without restarting the whole system. How do I restart it (or cause it to crash immediately to be restarted automatically by the OS) manually?


Covering with most possible equal size subsets having pairwise singleton intersections

Assume I have a non-empty finite set $S$ with $x=|S|$. I want to divide the set $S$ into subsets $S_1, S_2, .., S_n$ (Edit: Yes, $S = \cup S_i$, and I'm embarrassed that I forgot to include that) such that:     $ |S_i| = y, \forall 1 \le i \le n$  (The cardinality of each subset is fixed)   $|S_i \cap S_j| = 1, \forall 1 \le i,j \le n, i \neq j$ (Each subset has exactly 1 element in common with any other subset)   Edit: The second condition above excludes the possiblility of a pairwise disjoint division of subsets.  Is there a way to determine the maximum value of $n$ (the number of possible subsets), given $x$ and $y$?


finite and infinite product of discrete space

It is known that finite product of any discrete space is discrete. But infinite product of discrete space need not to be discrete. The main reason is that the any singletion in  infinite product space is never be open ? or is there any infinite  product of discrete spaces that each singletion is open subset in it?


Why there is a huge extra blank space at the beginning of this document?

After compiling following document, there is an extra blank space at the beginning of each page. I suspect there is an incompatibility between the lineno and pdfsync package. Is there a way to fix this problem?  \documentclass[a4paper,10pt]{amsart} \usepackage{pdfsync} \title{Title of article} \usepackage{lineno} \pagewiselinenumbers  \begin{document} \maketitle \section{Introduction} In the traffic court of a large mid-western city, a young lady was brought before the judge to answer a ticket given her for driving through a red light. She explained to his honor that she was a school teacher and requested an immediate disposal\linelabel{disposal} of her case in order that she might hasten on to her classes. A wild gleam came into the judge's eye. "You are a school teacher, eh?" said he. "Madam, I shall realize my lifelong ambition. Sit down at that table and write 'I went through a red light' five hundred times."  Line \ref{disposal} on page \pageref{disposal}. \end{document}   Related  and .


Does the Cobalcat appear in any other stories apart from "Tuf Voyaging"?

There's a great early SciFi book by George R R Martin called "Tuf Voyaging". In one of the chapters he uses his spaceship "Seed Ship" to create a bunch of alien monsters for a planet that fights it wars through monster arena battles.   He create a large cat like creature called a "cobalcat", it has infared eyes, and psionic abilities.   Has this cat creature turned up in any of his other short stories?   I'm sure I can remember a story about a human manned spaceship that crashes? or lands on an alien planet. While there they come across one of these cats that tricks them into thinking its harmless and benign. But eventually kills them once they take off with it on the ship? I think thats how it goes. I'm a bit murky on the details. Any help would be great. Thanks.


xfce4-Terminal doesn't create a new pts session?

I'm running Openbox on Manjaro, and I've come across a peculiarity trying to use write and wall with some friends. I use xfce4-terminal as my preferred terminal emulator, and I was never able to get any messages using these utilities.   If I logged in and did not startx, I could communicate on the base tty just fine. If I used Xterm things worked fine as well. I noticed though, that the xfce terminal does not create a new pts session, and the results of who showed only myself as tty1. However, trying to write or wall to tty1 here was no dice. ssh'ing from somewhere else, or using screen within the xfce terminal gave me a virtual pts, which could be written to.  I did note with w that the user on tty1 was running xinit /home/mmes/.xinitrc -- /etc/X11/xinit/xserverrc :0 vt1 -auth/yadayada all the time. This led me to believe that somehow the xfce terminal is sending commands through the x server somehow, without using a session of its own?  This situation has kind of baffled me, and I would love to hear thoughts why from someone who knows how these graphical terminal emulators actually work, as well as if they know how to write or wall messages there.


How do I disable network manager permanently?

I'm using Ubuntu 18.04.1 LTS. I want to disable network manager on an Ubuntu machine, because (1) I don't need it, (2) I prefer having hardcoded configuration, and (3) network manager regularly causes issues by changing the DHCP configuration. I tried to follow :  Stop network manager sudo systemctl stop NetworkManager.service  Disable network manager (permanently) to avoid it restarting after a reboot sudo systemctl disable NetworkManager.service   Despite this, the network manager is back again every time I reboot the machine. How can I make it go away?


Periods show up as hieroglyphs in TexMaker OS X

I am getting the following strange and somewhat annoying behavior in TexMaker for OS X 10.9:    It happens any time a period immediately follows a curly brace.  Why?  Is there any way to fix this...?  Thanks for any tips!


How do I enable 'minimize on click' on Ubuntu dock in 17.10 and later?

I am talking about when you click on the icons in the dock This command gsettings set org.compiz.unityshell:/org/compiz/profiles/unity/plugins/unityshell/ launcher-minimize-window true  which works for Unity Launcher, (obviously) does not work.  Related to:


finding if two binary quadratic forms represent the same integers

I am currently working with quadratic forms for a given discriminant D; to get all primitive forms (one for each equivalence class) I found this website :   For instance for the case D=-23, the three primitive forms are given by : (1,1,6), (2,1,3), (2,-1,3); and I know that the two last ones represent the same integers.  I need now to work with some discriminant such that the class number is larger (h(D)=4,5..) and I need to know if two forms represent the same integers. Would you know of a similar software where I can check this?  Thanks.


I am trying to install ubuntu 14.4 on a computer (actually into QEMU emulator) which does not use unity or any GUI, and only a command line which looks like the "terminal" application in fullscreen. I checked out , but I do not want server features, just ubuntu desktop features without the desktop. How can I do this, or possibly is there a way to remove the "server" from ubuntu server? EDIT: Ubuntu server appears to be only available for 64-bit machines. I am planning to run it within QEMU Emulator on a 32-Bit Toshiba Satellite machine running Ubuntu Desktop 14.4.


How to select generated element in Javascript

When I click start,some choices will be displayed.  I would like to select each choice by getElementById is it possible?  How can I change my work to achieve it ?  Thanks    document.getElementById("start").addEventListener('click',function(){   html=" ";   for (let i=1;i<=4; i++){     html+= "<button id='choice'>"+"choice"+i+"</button>
";   }   document.querySelector('.btn').innerHTML = html; });  document.getElementById("choice").addEventListener('click',function(){   console.log(this); });
<button id="start">start</button>


When to use "she's"(short form) and and "she is"(full form)? What is the difference?

Example : He isn't tired but she is. Why can't use "she's"? Why is "she is" used?