Will an SPI flash memory chip have the same issues with non-atomic write operations as a dsPIC's internal EEPROM?

I had some intermittent trouble with the internal EEPROM of a dsPIC. Every so often, some value in the EEPROM would be found zeroed out on power-on. I tracked the problem down to when the chip lost power after the erase step of the write cycle, but before the write had completed. It was all about the timing of the power-down relative to the firmware execution, which was (in normal operation) random. I solved this by adding a buffer section to my EEPROM, to ensure that an incomplete write-cycle could be completed on restoration of power. I had to turn EEPROM writes into an atomic operation.  Now I'm using a different dsPIC without internal EEPROM, and I'm trying to use an  to store persistent data. I'm wondering if I should have similar concerns. Should I be worried that my external flash chip will power down mid-write and lose data, and write a fix for this in my firmware like I did for internal EEPROM? Or does the chip itself guarantee atomic write operations?  For further detail, my buffering technique defines an area of persistent memory that consists of three fields: address to write to, data to be written, and a READY flag. A "write" consists of four steps: write to buffer, set READY flag, write from buffer, clear READY flag. On power-up, you check the READY flag. If it's set, execute whatever's in the buffer. This worked well in EEPROM, but I'm not sure if it will work well in flash.


Finding a point along a line a certain distance away from another point!

Let's say you have two points, $(x_0, y_0)$ and $(x_1, y_1)$.  The gradient of the line between them is:  $$m = (y_1 - y_0)/(x_1 - x_0)$$  And therefore the equation of the line between them is:  $$y = m (x - x_0) + y_0$$  Now, since I want another point along this line, but a distance $d$ away from $(x_0, y_0)$, I will get an equation of a circle with radius $d$ with a center $(x_0, y_0)$ then find the point of intersection between the circle equation and the line equation.  Circle Equation w/ radius $d$:  $$(x - x_0)^2 + (y - y_0)^2 = d^2$$  Now, if I replace $y$ in the circle equation with $m(x - x_0) + y_0$ I get:  $$(x - x_0)^2 + m^2(x - x_0)^2 = d^2$$  I factor is out and simplify it and I get:  $$x = x_0 \pm d/ \sqrt{1 + m^2}$$  However, upon testing this equation out it seems that it does not work! Is there an obvious error that I have made in my theoretical side or have I just been fluffing up my calculations?


When flying into the US, where do I go through customs?

Flight from Atlanta to Minneapolis-St. Paul and connecting flight to Calgary. From Atlanta do I fly out of the domestic or international terminal? Where do I go thru customs?


How to get contact from stolen Android phone?

I already read . And that answer did not work for me. I have explained it on the question.  My android phone was stolen. I need to get all contact of my phone. I had enable sync in that phone.  When I visit , it has only a very few contacts (only if contact has an email ). How can I get all contacts?


Why do i get this null error on method call?

i get this error, Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.example.cave.Area.setTiles(android.widget.ImageView)' on a null object reference  i tryed to make anything i know...  //this the main Area[] area = new Area[9];     ImageView[] tiles = new ImageView[9];     for(int i=1; i<=9; i++)     {         area[i].setTiles(tiles[i]);     } //this is the second class public class Area  {  ImageView tiles ;  public ImageView getTiles() {     return tiles; }  public void setTiles(ImageView tiles) {     this.tiles = tiles; }    //   i want to create tiles, 9 x 9, this is for area 1, than i want another area,    area 2, area 3 ... area 9... i want to create imageview array to call it in a    class of areas array... //


The  web browser is a 64-bit-only open source project based on Firefox.  I would like to see how is the performance compared to Firefox, apparently its better.  Being new to Linux, it's a challenge when it comes to packages that are not .deb. On the official site, Waterfox  as a .tar.bz2 file. How can I install Waterfox on Lubuntu 17.04 and also add an entry for it in my menu, under Internet, alongside Firefox?


Generate All Permutations...Need help understanding what is wrong with answer

Here is my answer in python for generating all permutations of a list It's not giving me the correct solution, and I'm not sure where I went wrong. sol=[] def prem(A,lis=[]):   if len(A)==0:     print(A)     sol.append(lis)   else:     for index,elem in enumerate(A):       print(A)       prem(A.pop(index),lis.append(elem))


How to specify Russian (foreign) authors in the bibliography of an article in English?

I am writing an article for publication in English. It is necessary to include references to articles written by Russian authors in Russian language. Do I have to translate their names and titles of their articles to English or I can leave their names and titles of the articles in original language (Russian)?  In the Russian-language articles, I see that foreign authors (their names and titles of the articles) are not translated into Russian and left in the original language (English). However, I have not seen articles in English, where Russian/foreign authors and articles were referenced in the original language (i.e. Russian).    For now, I am following  citation style.


Open files without extensions in PDF viewer per default

For some reason (backup system, different story) I have a bunch of PDF files without a file name extension.  It is  possible to configuere my PDF viewer as the default application for files without file name extensions (.pdf) ?  (Yes I know, this ist stupid question. It´s more a theoretical question :-) I know tools like TrID - File Identifier)


Requirements of the edges of a tetrahedron

What are the requirements of the six edges $a,b,c,d,e,$ and $f$ of a tetrahedron?  I know for each face of the tetrahedron, the three edges must satisfy the triangle condition. I also know by just satisfying all four faces does not meet the requirement of forming a tetrahedron. The requirements looks complicated. Can somebody helps me out?


How can I fix a 404 Error when using a PPA or updating my package lists?

PPA seems to be constantly offline. Whenever I use sudo apt-get update, this error is shown:  W: Failed to fetch http://ppa.launchpad.net/ 404  Not Found   How do I fix these errors?


Word for mildly popular (used as a compliment)

I'm trying to find a word for something meaning not explosively popular or successful, yet not a failure. It should not be intended as criticism and should represent something not necessarily new but more forthcoming or predicted to be destined for eventual greatness.     Alphie's _______ novel Xyz is a ....


How should a website's title be structured?

Are there any best practices for choosing the title of web pages? There are a lot of resources online oriented toward SEO, but not toward users.  My impression is that most sites have something similar to Product - Page. But there are cases when switching this around is more useful. For example, if mail clients displayed the title like this:  Inbox (3) - Gmail  Instead of:  Gmail - Inbox (3)  You would be able to see the message count, even if the title was cut off. (I'm pretty sure Gmail used to do this).  I assume the title is mostly ignored by users except when:   using boorkmarks finding the right tab in the browser   What are the considerations for users when choosing a web page title? Are there different considerations for the home page, pages behind a login, etc?


Since when did the Community user edit posts?

Now I have truly seen everything. The community user does a lot of things, but editing answers to add information? Now that is truly bizarre. What am I talking about? Have a look at the revisions to  question. Yeah, that's right - the community user suggested an edit that adds to the answer. What is going on? Do we need to fear the new intelligent bots? Should we run for cover... or should we try to get rid of it? A plausible explanation of what happened here would be great if nobody can think of a good defense strategy.


I found this declaration in a piece of code involved in a puzzle, could anyone explain what it's doing? I've tried looking myself but I don't really understand.  test = [[0] * 9] * 9


Does a Druid in Wild Shape add their own Proficiency Bonus to the physical attribute of the Beast for Skills?

The PHB entry on Wild Shape states: "You also retain all of your skill and saving throw proficiencies, in addition to gaining those of the creature."  Does this mean you add the character's Proficiency Bonus to the beast's physical attribute modifiers to arrive at the Skill total? For instance, my Druid has a PB of +3, proficiency in Stealth and an 18 Dex, for a total of +7 Stealth in normal form. But in Polar Bear form, her Dex drops to 10...does that mean I'd only be at +3 in Stealth in bear form?


How do I become root when "su -i" is not supported?

As far as I know the following command is supposed to make me root:  su -i   Nevertheless, when I type it in Ubuntu 17.04 Zesty Zapus, I get the following message:  su: invalid option -- 'i' Usage: su [options] [LOGIN] Options:   -c, --command COMMAND         pass COMMAND to the invoked shell   -h, --help                    display this help message and exit   -, -l, --login                make the shell a login shell   -m, -p,   --preserve-environment        do not reset environment variables, and                                 keep the same shell   -s, --shell SHELL             use SHELL instead of the default in passwd   I remember it was working some time ago. How do I re-enable it?


To prove that, a graph $G$ is bi-colored iff, when in it doesn't have a cycle of odd lengths. How to prove this theorem, I need some hints/resource recommendation.


I'm travelling from UAE to London through Fiumicino airport . Do I need an Anairport transit visa for a 2-hour layover in the Fiumicino airport? I hava a valid visa to Uk


What did Louise say to the Chinese President in the movie Arrival?

In the movie Arrival, Loiuse, played by Amy Adams says something to the Chinese President, which he claims were his wife's words. I think she is speaking Mandarin but no subtitles are provided. What did she say?


What is the largest possible order of a permutation in $S_{n}$?

I was trying to solve the following question (from this ):     What is the largest possible order of a permutation in $S_{10}$?    I though there is some sophisticated way to solve it but then I read the solution (also located in the link). Is there a better, more sophisticated way to solve such problems for $S_n$, then writing down all the elements and their orders?  For example, finding the largest possible order of a permutation in $S_{101}$  will be much harder.


How to change entire SQL server location from C:\ program file to another drive?

scenario:  one of my client was asked me to move entire program files folder from C:\ drive E:\ drive and change the all databases location to E:\ drive. They have copied entire program file folder through third party tool and pasted it on E:\ drive and they asked me to change path of databases and SQL installation to E:\ drive. Now how to change all databases paths and how to do this kind of activity? i know how to move system and user databases manually from one drive to another but i haven't face this king of scenario. Please suggest me how to do this task without any errors.


Do stat boosts affect DoT effects already in play?

I'm playing Witch Doctor and making use of several of the wonderful Intelligence boosts they can get (Gruesome Feast, Soul Harvest...). I need to know when to time these boosts, however, to get the best use of them. So, how does gaining Intelligence affect the following?   A Grasp of the Dead in play Corpse Spiders already thrown Monsters already taking damage from Locust Swarm or Haunt and lastly, minions in play, like Gargantuan   This question could be used in general for other classes as well, I just used Witch Doctor as an example.


I did      iostat  -Id disk0   on my MacBook Pro (MacOS Sierra) and found the total number of reads/writes done on the SSD. Is it true that this is indicative of the age of the MacBook? Should a new MacBook have very few reads/writes? Mine has a power cycle count of 10 but a very high number of transfers (2050247) at 28.6 KB/t i.e. around 55GB worth of reads and writes. Something seems off here...


Get single char from console immediately

Is it possible to get each char from STDIN once it is provided (without waiting for return key)?


Mathematical notation for a conditional sum

I'm looking for the correct way to define a sum of all elements in a set that fullfill a certain condition.  Example: $$ n(A) = \frac{\sum_{F \in A}{ \begin{cases} A_F\text{ is }\mathrm{NULL} & w_F\\ \text{else} & 0 \end{cases}}}{\sum_{F \in A}{w_F}} $$  A is to supposed to be a record with a number of fields $F$. $A_F$ is the value of field F in the record A. $w_F$ is a weight associated with the Field $F$. I want to calculate how much percent of the record is NULL weighted according to $w_F$.  What I want to know is if this below is a valid way to formulate this or if there is a better way.  If someone has some pointers on a more formal / mathematical notation for database/records I would also be very grateful.  Thanks!


What is a multiwire branch circuit? (also known as "multiwire circuit", "multiwire branch circuit", "split phase shared neutral", "two circuits fed from one 12-3 or 14-3 NM-B cable", "shared neutral circuit",  etc) This question comes up from time to time on this site, and I couldn't locate a canonical answer about what a multiwire branch circuit is. They seem to be relatively uncommon in residential wiring, so many homeowners may not know how to recognize or handle them, especially when taking on "simple" DIY projects like adding a GFCI or AFCI outlet or breaker. This boils down to multiple sub-questions, but I think they are related enough to answer here:  What is a Multiwire Branch Circuit? How do I know I have one? What do I need to do differently when working with one?  A few related questions that give various pieces of the answer are:


Can We Input Return Using Shell Scripts?

I want to use adduser USER (USER is a user name), but this asks me many questions like full name and address. I want a script which types the return key automatically and skip those questions. For example, I execute ./myadduser.sh USER and myadduser.sh call adduser USER and input return to all questions. Is there a great way to do this? I am thinking about Ubuntu 14.04.  Sorry, I made a mistake. Input return not to all questions since I have to input password which cannot be return. Is it possible to input return to all questions except questions about password?


Finding source code for all geometry tools of QGIS

I want to find the Python source code for tools like Merge Lines, Multiple parts to single parts, Intersection, Difference etc. I am not having any luck finding them online. Does anyone know any links to Python code? I am using QGIS 3.18.1.


What do I need to destroy to get all the Dark Elixir in a village?

I want Dark Elixir.  My question is, if it is shown that 1000 Dark Elixir is available as loot in someone's village, and I destroy his storage with lightning spells, will I get all 1000 Dark Elixir, or do I need to destroy the Dark Elixir drills and the Town Hall too in order to get it all?


'I have decided to purchase a jet for getting to NYC and back more quickly.'

Are the following sentences grammatical or not? If not, does substituting a to-infinite make them grammatical? (Optional: designate if the sentence expresses purpose, reason, aim, or function)  1 I have decided to purchase a jet for getting to NYC and back more quickly. 2 I have decided to buy a jet for having a quicker way to get to NYC and back.  This is my only reason and aim; this will be the jet's only purpose and function.  3 I hate hairdryers, so I am buying a space heater for drying my hair more naturally, and that is my only aim & purpose & reason and that will be its only function 4 For having a lasting shine in your hair, buy ShineOn Shampoo. 5 My neighbor and I have decided to cooperate more for having a better life together.   Research done: ELL  (Note the  here is a restatement of Cambridge Dictionary's ) ELL  ELL  BBC English  (Currently the best site I've found.) ELU  All of which have answers that I find  (i) incomplete (ii) contradictory (iii) terribly confusing, if not (iv) wrong. To sort through the haze, I am focusing on one issue. Background Some sources say that you need to use a to-infinitive for expressing purpose, aim, function, reason, etc. I find these to be rather hazy distinctions, given that the ODO defines  as The reason for which something is done or created or for which something exists and the same work lists as : aim, reason, function, etc. It is my assertion that at least some of the following sentences demonstrate that one can use the -ing form (be it a gerund, verbal noun, participle) to express individual purpose (aim, reason, function, intention, whatever you want to call it). Do you agree, or not? Why (not)?  In shorter terms, are the sentences grammatical? or do we have to substitute a to-infinitive (including in order to + infinitive) to make them grammatical? (Optional: designate if the sentence expresses purpose, reason, aim, function, etc.)


Google Play Store - No Connection (Galaxy Note 3)

I'm have connectivity issues with the Google Play Store app.  I have a non-rooted Note 3 (4.3).  The had worked the first few weeks I had the phone in December and then hasn't worked since.  I get the same "No connection - Retry" error everytime I access it.  I've been have trouble with Google Play Services since I tried disabling it when I realized how much battery life it drained.  I've had trouble using Youtube at times but never as persistent and consistent as the Play Store.  I have done the following:   Wi-fi/LTE connections, no difference between the two Airplane mode on/off Manual and automatic date/time Updated both Google Play Services and Google Play Store via Android Police   I have basically done everything except a factory reset which seems like the next logical step but it does not fix the problem for everyone.  I am trying to figure out if there is anything else I haven't tried that I may be overlooking.  Thank you!


For example, if I had a dark blue or black background choosing white text will make it stand-out and more readable.   If I had a white or off-white background, black text will stand-out and be readable.  What do I do if the background color is neither dark enough for white to show well nor light enough for black to show well?


Say I need to build n lambda functions, and put them into a list:  n = 6 lamd_list = [lambda x: x * i for i in range(n)]   Here x is input of the lambda functions, and the i is intended to be fixed to 0~5 in the list. However, when I run:  lamb_list[0](3)   The output would be 15 (3 * 5) instead of 0 (0 * 5). How can I modify the code to make it do as I intended? Note that here the n is a variable (not fixed), so I can't do the loop manually. Also, I don't want i as an input to the lambda function.


Driving a LED with an open drain digital output

I need to drive an LED from an .  So I was thinking about a classic circuit with a BJT.  But then I saw that GPIO outputs of the microcontroller are configurable as open drain.  Would this circuit work?    The LED has a 20mA forward current and a 2V forward voltage. Considering \$R=(3.3-2)/0.02\$ it should be on, if GPIO is Hi-Z and off, if it is GND, right?  I don't see why this circuit would not work but I've never seen it before, so I just want to be sure before designing it.  Edit: Then you mean it is better to do this:    Edit 2: Finally here is the schematic I'll be using (the output GPIO LED6FAIL is 3.3V and it's a push-pull):


How reliable is validating email domain by reverse DNS MX record checking

This question is not about how to protect against spam or validate a particular email user. But how reliable is validating emails domain (does it exists at all) by reverse dns. What are the pitfalls of this method?  I don't care in this part is it some spam address or not, I just want to know if domain exists at all and is able to receive and send emails.  Like in title, how reliable is this check. I want to validate emails domain name, if it exists. I've asked similar question on board for programmers, but I can't get full answer, so I think this board will be better for such question.   Every single server in the world have their MX record exposed to the world? Or is there a possibility that there exists a server that hides their MX record and even if email will be valid, check will fail.  I know and I've tested that only emails domain is checked, not the user part. I just don't know how reliable it is. Is it always possible to check servers MX records.  With some more research I have found that some servers use something like MTA for mail exchange which don't use MX record. If I check A/AAAA records then, will that be enough?


I'm trying to prove the following equation above. So far I have: \begin{align} 2^{2n} &= (1+1)^{2n}\\ &= \sum_{k=0}^{2n}\binom{2n}{k}1^k1^{n-k} = \sum_{k=0}^{2n}\binom{2n}{k} & \text{(By the Binomial Theorem)} \end{align}  I know I have to use the following identity somehow: $$\binom{n+1}{k} = \binom{n}{k-1} + \binom{n}{k}$$  How do I split my summation to get what I'm looking for? Thanks!  EDIT: HERE IS MY SOLUTION \begin{align*} 2^{2n} &= (1+1)^{2n}\\ &= \sum_{k=0}^{2n}\binom{2n}{k}1^k1^{2n-k} & \text{(By the Binomial Theorem)}\\ &= \sum_{k=0}^{n}\binom{2n}{k} + \sum_{k=n+1}^{2n}\binom{2n}{k}\\ &= \sum_{k=0}^{n}\binom{2n}{k} + \sum_{k=n+1}^{2n}\binom{2n}{2n-k} & \text{(Binomial Symmetry)}\\ &= \sum_{k=0}^{n}\binom{2n}{k} + \sum_{k=0}^{n-1}\binom{2n}{k}\\ &= \sum_{k=0}^{n}\binom{2n}{k} + \sum_{k=1}^{n}\binom{2n}{k-1}\\ &= \binom{2n}{0} + \sum_{k=1}^{n}\binom{2n}{k} + \sum_{k=1}^{n}\binom{2n}{k-1}\\ &= \binom{2n}{0} + \sum_{k=1}^{n}\binom{2n+1}{k} & \text{(By Identity listed above)}\\ &= \sum_{k=0}^{n}\binom{2n+1}{k} \end{align*}


Can't include a 'tabu' inside \newenvironment with cells in the postamble

I'm trying to include a tabu inside a new definition of an environment but it fails if the postamble (enddef) of the new environment includes tabu's contents, so cells. With tabular or tabular* works. The error is:   ! Missing number, treated as zero. \tabu@0.H5   The MWE:  \documentclass{article} \usepackage{tabu} \newenvironment{testt} {\begin{tabu} to \textwidth{cccc}  11 & 12 & 13 & 14 \\  21 & 22 & 23 & 24 \\} {  41 & 42 & 43 & 44 \end{tabu} }  \begin{document}  \begin{testt}  31 & 32 & 33 & 34 \\ \end{testt} \end{document}   How to solve this?


We know a sound wave is a disturbance that moves through a medium when particles of the medium set neighboring particles in motion. And using the pressure variations we can plot a  pressure/time graph which looks like a 'wave'in the drawing sense.  What do we mean when we say light is a wave and particles? using the above system, can we  say that light is the disturbance that moves through a medium of photons( forgive me that makes no sense). When we draw a light 'wave', what does it mean? a photon goes up and down?  Please keep the answer as 'not complicated math' as possible.


How do Hrbacek and Jech derive the class function $F$ in Theorem 4.12 from Theorem 4.11?

My question is about a proof of Theorem 4.12 given in the text Introduction to Set Theory by Hrbacek and Jech.   Let $V$ be the class of all sets, $\operatorname{Ord}$ be the class of all ordinals, and $G,G_1,G_2,G_3$ be class functions from $V$ to $V$.  Theorem 4.11:  There exists a class function $F:V\times\operatorname{Ord}\to V$ such that, for all $z\in V$ $F(z,0)=G_1(z,\emptyset)$ $F(z,\alpha+1)=G_2(z,F_z(\alpha))$ for all $\alpha\in\operatorname{Ord}$, with $F_z(\alpha):=F(z,\alpha)$ $F(z,\alpha)=G_3(z,F_z\restriction\alpha)$ for all $\alpha\neq 0$ limit, with $F_z\restriction \alpha:=\{\langle\beta,F(z,\beta)\rangle\mid\beta<\alpha\}$  Theorem 4.12:  For any set $a$, there is a unique infinite sequence $(f_n\mid n\in \Bbb N)$ such that (1) $f_0=a$ (2) $f_{n+1}=G(f_n,n)$ for all $n\in \Bbb N$  The proof for Theorem 4.12 is given in the text as follows:  Let $G:V\to V$ be a class function. We want to find, for every set $a$, a sequence $(f_n\mid n\in \Bbb N)$ such that $f_0=a$ and $f_{n+1}=G(f_n,n)$ for all $n\in \Bbb N$. By Theorem 4.11, there is class function $F$ such that $F(0)=a$ and $F(n+1)=G(F(n),n)$ for all $n\in \Bbb N$. Now we apply the Axiom of Replacement: There exists a sequence $(f_n\mid n\in \Bbb N)$ that is equal to $F\restriction \omega$ and the Theorem follows.   I don't understand how Theorem 4.11 is used to derive the class function $F$ in the proof of Theorem 4.12. Can someone elaborate on how to obtain the desired $F$? Thank you for your help!


Suppose $x,(y > 0)$ are real numbers. I want to know if it is true that for small $t$, we have  $$ (tx)^2 + (ty)^2 \leq 2ty $$


I want to install ns2.35 on Ubuntu 14.04. When I implement this command:  $ sudo apt-get install tcl8.5-dev tk8.5-dev Reading package lists... Done Building dependency tree   Reading state information... Done E: Unable to locate package tcl8.5-dev E: Couldn't find any package by regex 'tcl8.5-dev' E: Unable to locate package tk8.5-dev E: Couldn't find any package by regex 'tk8.5-dev'   What should I do for resolving this problem?


What does 2 to the power x mean in set theory

In a mathematics assignments i encounter the following statement:  We have a finite collection of combinatorial objects $S \subseteq 2^x$ (For example matchings or spanning trees)  What does this notation $S \subseteq 2^x$ mean (Especially the $2^x$ part)?


I need to create a cloud mask using the pixel_qa band, this is the code that I have so far:    var city = ee.Geometry.Point(9.15, 45.18); var landsat8 = ee.ImageCollection('LANDSAT/LC08/C01/T1_SR')  // Fmask classification values   var mosaic = landsat8      .filterBounds(city)      .filterDate('2017-08-01', '2017-09-01')      .mosaic();  var getQABits = function(image, start, end, newName) {     // Compute the bits we need to extract.     var pattern = 0;     for (var i = start; i <= end; i++) {         pattern += Math.pow(2, i);     } // Return a single band image of the extracted QA bits, giving the band a new name. return image.select([0], [newName])               .bitwiseAnd(pattern)               .rightShift(start); };  // A function to mask out cloudy pixels. var cloud_shadows = function(image) {     // Select the QA band.     var QA = image.select(['pixel_qa']);     // Get the internal_cloud_algorithm_flag bit.     return getQABits(QA, 3,3, 'Cloud_shadows').eq(0);     // Return an image masking out cloudy areas. };  // A function to mask out cloudy pixels. var clouds = function(image) {     // Select the QA band.     var QA = image.select(['pixel_qa']);     // Get the internal_cloud_algorithm_flag bit.     return getQABits(QA, 5,5, 'Cloud').eq(0);     // Return an image masking out cloudy areas. };   I tried to create a mask using the Map.addLayer but the result is only a white mask. What I need is to create a mask in which clouds are displayed with a certain color (ex. white) and all the other pixel type with another color (ex. black).


Is there a way to draw a Voronoi diagram with pgfplots?


As a package developer scratch orgs look like a great solution for automated CI testing and Salesforce has even done some great demos using Github and TravisCI to show automatically testing code using the DX CLI. However, in reviewing the details of DX, it looks like the limit is currently set to 50 orgs a day. If we want to test pull requests against 5 different org configurations, this limits us to 10 test runs a day. On a moderately sized team, this is going to be a tough limit to deal with. Has anyone had any success in working around this limit (or heard of any planned limit increases in the future). My initial thoughts are:   Get Salesforce to increase the limit (does not seem likely since this is a very young feature) Reuse scratch orgs for a period of time (this would require a good way to clean them and some savvy CI build code) Run fewer tests (not going to go over well the first time a bug for a specific org configuration slips through)


Sum of columns for rows containing a specific term

I'm wondering if there is any sed or awk command that can sum all columns for the rows with an identical identifier. For example, my file data.txt is set out as below, except that it contains ~1800 columns of data and ~1400 rows.  ABCD:1234  1.23  0.23  0.83   0 ABCD:1234    0    1.10  0.21   0  EFGH:5678    0    1.90  0.12  8.21 IJKL:9999    1.22  0    1.84  9.21 IJKL:9999    1.44  0   12.94   0 IJKL:9999    1.32  0   24.12   2.43   And how I would like it to be after the command would be like this:  ABCD:1234  1.23  1.33  1.04  0 EFGH:5678    0    1.90  0.12  8.21 IJKL:9999   3.98   0   38.9  11.64   I'm not sure if this is even possible with awk or sed (I'm a biologist and still learning the basics of Unix). Any help would be much appreciated.


cant upgrade by sudo apt- get upgrade, hash sum mismatch, ubuntu 16.04, problem upgrading firefox

Get:2 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libxatracker2 amd64 17.0.7-0ubuntu0.16.04.2 [1,106 kB] Err:2 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libxatracker2 amd64 17.0.7-0ubuntu0.16.04.2   Hash Sum mismatch Get:1 http://archive.ubuntu.com/ubuntu xenial-security/main amd64 firefox amd64 57.0+build4-0ubuntu0.16.04.5 [43.6 MB] Err:1 http://archive.ubuntu.com/ubuntu xenial-security/main amd64 firefox amd64 57.0+build4-0ubuntu0.16.04.5   Hash Sum mismatch Fetched 88.4 MB in 3min 20s (441 kB/s)                                          E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/f/firefox/firefox_57.0+build4-0ubuntu0.16.04.5_amd64.deb  Hash Sum mismatch  E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/m/mesa/libxatracker2_17.0.7-0ubuntu0.16.04.2_amd64.deb  Hash Sum   mismatch  E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?


UK visitor visa refused. Tax return and business account not considered as proof of income

My parents' visitor visa was refused and here is the full scenario.  My father is self-employed and hence earns yearly profit and doesn't draw a monthly salary. He doesn't have regular deposits in any of his savings accounta, and all his transactions are carried out via his business account.  He was self-sponsoring the trip as we were planning to sponsor my in-laws. As a proof of funds he submitted his business account details and one savings account detail. Unfortunately the saving account has a single lump sum transaction and the balance is low.   They didn't mention the business account in the refusal letter at all. He provided an IT return file which they termed as "self-declared" and "self-completed". His income is not fixed hence the income quoted was an estimated one and his IT returns shows that even though he quoted say INR 40k per month, last year it was 30k per month and last to last year it was 35k per month. His income tax is audited by a chartered accountant.  Also he estimated the cost of the trip at 2.5 times of the monthly income. He had submitted property tax receipts as proof of property and trade license as proof of employment. They are asking for "proof of income".  Mother's refusal  She is a housewife and she was being sponsored by my dad. Since in the form the column of income from other sources like investment and savings were written null, they didn't consider her fixed deposits and savings account details (which has a decent amount maintained for more than a year). She has no property in her name.  I am their only child and my maternal grandmother is alive.  We don't have our spouse's name in me and my husband's passports. But we do have marriage certificate and affidavit stating that I can use both my husband's surname and my maiden name.  My father has intimation notice of his IT returns system generated by IT department and digitally signed by IT officer which acknowledges his IT returns. (it is different from the IT return file receipt that he submitted).  He has more than enough money in his business account but we do understand that business account is not considered as proof of income.  Our own visa is only valid for exactly a year more as we have to leave after 12 months.  My husband can sponsor them easily and we wish to apply again after 2 months.


Equivalent to command prompt's "tree" command?

Back in my (sucky) Windows days, I used the tree command to view the file hierarchy in a pretty display. I am aware of the find command, but to actually process any data in my clogged 241,416 folders/files from just checking each line is as possible as time travelling... ./build/CMakeFiles/cmake.check_cache ./build/CMakeFiles/Makefile.cmake ./build/CMakeFiles/CMakeTmp ./build/CMakeFiles/TargetDirectories.txt ./build/CMakeFiles/compilerid.dir ./build/CMakeFiles/compilerid.dir/depend.make ./build/CMakeFiles/compilerid.dir/flags.make ./build/CMakeFiles/compilerid.dir/DependInfo.cmake ./build/CMakeFiles/compilerid.dir/link.txt ./build/CMakeFiles/compilerid.dir/build.make ./build/CMakeFiles/compilerid.dir/cmake_clean.cmake ./build/CMakeFiles/compilerid.dir/main.o ./build/CMakeFiles/compilerid.dir/CXX.includecache ./build/CMakeFiles/compilerid.dir/progress.make ./build/CMakeFiles/compilerid.dir/depend.internal ./build/cmake_install.cmake ./build/CMakeCache.txt ./build/Makefile ./build/compilerid ./CompilerID.kdev4 ./.kdev4 ./.kdev4/CompilerID.kdev4 ./main.cpp  Output of find on one folder holding the files of a one-file, incomplete C++ project On Windows, the tree command gave a diagram-like output that is human readable   Screenshot of the pretty tree command So, my question is, is there anything graphically close to the Windows/DOS tree command?


Is the sentence "Those two are triplets" proper? It seems like it would not be correct, because triplets come in 3 and this only references two people.   A similar case would be "He is a twin." I think this is different though because twin is singular, and triplets is plural.  If I was only pointing out one, "He is a triplet" seems correct. I feel that when using triplets, it implies 3.


I want to re-position the display on my ASUS K53SM laptop's screen because I somehow managed to damage some portion of it (and I don't want to spend on this laptop for the time being).  Please refer the following image:    I changed the resolution from 1366x768 to 1280*768 to avoid the bad portion of the screen, but the screen is now centered and the right portion of my screen is now rendered useless.  What I want to do is, set a custom resolution of my laptop and re-position it in a way that is utilizes all the working area of my screen.  How do I re-position the displayed image on my laptop?


Would you compromise your design and how far should you go?

I am pretty sure that most of us here, or at least those do graphic design for living, have found themselves in following situation:   You agree with a client to do the design, agree on price, schedules, formats etc… You work hard, make adjustments, collaborate with client; everything goes well in the beginning. At some point you realise that the client does not listen your professional advice regarding design and prefers his/her own ideas that might not look so professional (choice of fonts, colors, odd choices of elements, shapes etc…). No matter how hard you try, the client is persistent and will not accept the designer’s advice. You get back to work, try to make the best out of it, and the final result is not so good, mainly because you had to stick to the client’s wishes. Work is shipped, payment done, and you don’t want to include this work in your portfolio because it is not good. After all, it is not your work, it is something that was physically created by you as a designer, but the ideas, concept, story, and message came out as a result of nonprofessional person, your client.   Ok, they pay for it, and as long as they are happy this is fine. But, the more compromises you make, the more time you spend working on bad design. If you are a young designer on a quest to get recognition, you don’t want to work just for the sake of money and then face the lack of good design in your portfolio.   Maybe at the beginning of your career you don’t care that much, but later if life this might be a big issue. At some point you will be approached by a big client that might offer you long-term contract, but first they will want to see your work. No point explaining to them what you did and why you made so many compromises.   They will not be interested in that.  Every project is precious as your time and you want to do use it wisely and produce great work.   How would you deal with such a situation?


I wish some advise.  We have a quote from a VAT Registered building company for work on an extension, this quote for simplicity was 50k GBP. At the end of the list of items on the quotethey will complete (doors, plastering, windows electric) they give the 50 k GBP subtotal.   After the above line on the quote they say this verbatim “20% all costs are plus VAT at standard rate”.  On receiving this quote, I found this very confusing as I did not understand what the word costs related, to the items or the total. I verbally queried if the amount 50k included VAT or not, I understood the answer to be no it was 50 k including the VAT.  We start the work, then first bill includes a agreed percentage let’s say 40% of the work. The expected amount was 20k but instead I get a bill for 20k plus VAT I.e 24k.  What are your thoughts? Stupid me or misleading?


Can't execute .out files, getting permission denied

I have written a C++ program and complied it to produce a.out file. However, whenever I try to run it, I get Permission Denied. I read that we can use sudo, but I can't quite get it to work. I use something like, sudo "./a.out" but that too doesn't work.  Edit:  Here is the message I get when I try "./a.out".  bash: ./a.out: Permission denied


I have read that many times that a compiler translate a high level code into machine language and whenever I google "machine language" it tells me it is the assembly language. On the other hand when I opened a hello world app written in c++ with notepad it showed me something which was anything but assembly. What actually is the secret behind this stuff and also where did the binary and bits come in? Please solve my confusion.


How to recreate subpixel anti-aliasing like Windows Command Prompt

I want to be able to create a anti-aliasing effect as shown in windows command prompt with any text or vector I'd like without having to screenshot it within the program. How could I go about doing this?


Calling foreign phone number that happens to be in the same country

I am French but currently living in the US. I have a French cell phone number (+33XXXXXXXXX). Would someone calling me from the US be charged an international call (the +33 prefix being more important than the actual geographical location of the phone)?


i am using batch and i need help formatting this one thing, on saved file the date changes everyday but the "yyyy" is just put down as "yy" Example: if the year was "2021" the name would be "21" I havent found anything that could get me the last 2 numbers on the year. Please help as i need this for work. Sincerely, Kythe


For which values does the Matrix system have a unique solution, infinitely many solutions and no solution?

Given the system:  $$\begin{align}  & x+3y-3z=4 \\   & y+2z=a \\  & 2x+5y+(a^2-9)z=9 \end{align}$$  For which values of a (if any) does the system have a unique solution, infinitely many solutions, and no solution?    So I am getting that it has: infinitely many solutions at: (-1)    No solution at (1)    Unique solution at (-1,1)    AM I RIGHT??


Holed none-copper clad green epoxy glass soldering problem vectorbord model

TO MODERATOR  Tis question is different from the post from   DO NOT MARK AS DUPLICATE AS HAVE MANY PEOPLE LINK TO THIS PAGE TO ASSIST ME WITH IDEAS.  Placing a fake link  is completely impolite , rude an uncalled. ................................................................ I am very new at electronic soldering.  I got a different type of prototyping board which can not determine how to properly solder components.  It is a Vectorbord green epoxy board with holes but no copper clad.  I tried to solder with flux and solder from Radio Shack but the solder does not bond to the board.  I have look the specification but I am to able to determine if these type of board are for etching or just need a specific solder and flux.  Please help.


How to create these kinds of graphics in Illustrator? Do they have a technical name?

I'm just wondering how these kinds of graphics are created, i.e. the white lines that twist and turn across the page. I see them all the time and was just wondering if there is a way to create them in Illustrator using the Blend tool or wrapping a grid along a path? I'm not sure. Thanks!


Can I find out through find my phone where my phone last was when the battery died?

I can't find my iphone 6 using find my phone and I am not sure if the battery has died or someone turned it off.  Is there any way to find out the last location of my iphone before the battery died or the phone was turned off?


Word "save as" folder no longer original folder after Mavericks

Following upgrade to Mavericks, Word for Mac 2011 has different "save as" behavior.  WAS: "save as" would default to the directory of the current/open file.  Now: "save as" directory goes to word default, requiring navigating back to original drive/folder/subfolders.   Problem further described in this support thread:   I'm a lawyer and saving new versions of a document with new dates or marked changes is industry standard (no internal "versions" for us!) as a method of version control. I believe more people must have this problem. Time-wasting and incredibly hard to change a process that's been in place for years and years.


Ideals in $\mathbb{Z}[X]$ with three generators (and not with two)

It is well-known that in $\mathbb{Z}[X]$ we do have non-principal ideals, for example $(2,x)$. This is an ideal with two generators. Now I was wondering if there exists an ideal with three generators, which cannot be generated by two elements. (And of course, if so, if we can find ideals with $n$ generators which cannot be generated by $n-1$ elements).  I do have one suggestion: $(8, 4x, 2x^2)$, found by trial-and-error.  My question is twofold:    Is this an ideal as described above?  Is there a more constructive way to think about this question?


You dont currently have permission to access this folder error

I bought a new SATA Hard drive and installed a fresh copy of Windows 7 on it. I also installed my old one beside the new SATA HD.  Now I want to access my images / musics and videos but I get this error:      You dont currently have permission to access this folder, click continue to permanently get access to this folder    and when I click continue, I get this new error:      You have been denied permission to access this folder   when I go to the securiy tabs, my username (which is also the administrator on the pc) is not there - My new HDD is called C: and the old one is E: - I tried  and run the CMD - but the CMD directory is:     C:\Windows\System32>   and my drive is E:.


How can I reapply for my refused B1/B2 Visa (Denial under 214B)?

Got my B1/B2 visa refused 20 days ago under 214-B. He just asked normal questions like why, with whom, for how many days, how much experience I have and how much I earn... and refused it.  I have 1.8 yrs experience and have a package of 240000 INR per year. I needed to re-apply asap.  What should be the best route I take to get it approved? When can be the best time? Will the bond of 3 yrs work? or what type of strong evidences I can show?


I have an application which takes the information of a mysql database(a music-db) and shows it via echos in a div. Everything works fine.  Now I wanted to add a search bar so you can search the database for a specific song.   The search bar just loads a php file with a mysql query. The word or the letters you want to search for are passed via a varbiable in the link(for example test.php?searchvalue=it).  Now my problem: I get the following Mysql-error:     You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1   The quotes in the error are single quotes!  The Query is:  $searchvalue = $_GET["searchvalue"];  $query = mysql_query("select SongID, Songtitel, artwork, duration, SCID from tMusic where Songtitel LIKE '%$searchvalue%'") or die(mysql_error());   Why is this wrong?  Thanks for help.


i have an array of card types that looks something like this  var cards = new Array();  cards [0] = {name: "VISA", length: "13,16", prefixes: "4", checkdigit: true}; cards [1] = {name: "VISA_DELTA/ELECTRON", length: "16", prefixes: "417500,4917,4913",     checkdigit: true};   however id like to be able to find the card type depending on the card number entered. e.g if they select their card type from a drop down list i.e visa, then the credit card number should start with 4 otherwise when they submit the form a message of some sort should be display saying this is (whatever card it is, please change card type). Any help would be appreciated.  the id for the card number text field is CardNumber. Im not sure what other info may be needed, i have a function called Validate which validates the rest of the form and a function call Calculate which does the luhn check.


Calculating percentage of overlap between 2 features from 2 different layers using ArcGIS Desktop?

I have two layers. Layer 1 has features that are property/parcels with area in acres. Layer 2 has features that are wetlands/bodies of water with area in acres. I want to calculate parcels that have for example 0% wetlands, 10% wetlands, 20% wetlands, 30% wetlands etc. to 100% wetlands.   How can I do this on ArcGIS Desktop?   Ideally, I want to find parcels/properties that have a limited number or a limited percentage of wetland coverage.


Is it possible to close browsers, using JavaScript, PHP, or HTML without a prompt?  I was using this answer:   I was using Internet Explorer but it has since been updated to version 10 (soon to be updated to 11) and this exploit does not work.  If there is a solution in a different (but updated) browser, that could work as well.


root of prime numbers are linearly independent over $\mathbb{Q}$

How can we prove by mathematical induction that $1,\sqrt{2}, \sqrt{3}, \sqrt{5},\ldots, \sqrt{p_n}$ ($p_n$ is the $n^{\rm th}$ prime number) are linearly independent over the rational numbers ?  $\underline{\text{base case (n=1)}}$: $1,\sqrt{2}$ are linearly independent over the field $\mathbb{Q}$ otherwise $a1+b\sqrt{2}=0 \Leftrightarrow \sqrt{2}=-\frac{a}{b}$ which is absurd.  Then I am stuck.


SEO - does Google read dynamic canonical tags?

I used the following code to redirect all the HTTP pages of a site to the https:// version.  <link rel="canonical" href=""> <script>     var url = window.location.href; // get current URL     var link = document.querySelector('link[rel=canonical]'); // get the link element     var changedUrl = [url.slice(0, 4), 's', url.slice(4)].join(''); // change the URL to https://     link.setAttribute('href', changedUrl); // set href attribute of link element </script>   Now my questions is, will Google read the dynamically generated canonical tags and index them like normal canonical tags? Or will I have to try another approach?


How to fix Cannot create PoolableConnectionFactory (FATAL: password authentication failed for user )

I am working on project using GeoServer, PostgreSQL and docker. I am newbie in all these technologies. I publish new layer in GeoServer and when I try to preview, my browser tries to download instead of showing preview as it does before. I had the idea to delete container and recreate with pulling the last image again. Once done, nothing not working anymore. And I lost some data. I check I get missing styles, and I recreate some of them. The issue now is I do not be able to see my preview. I can see only the last layer I added, but when I check in GeoServer workspace data folder, I see my layers folders but it seems that something is missing. I re-check and I get this error. java.lang.RuntimeException: Error getting FeatureType, this should never happen!  Error getting FeatureType, this should never happen!Unable to obtain connection:  Cannot create PoolableConnectionFactory (FATAL: password authentication failed for user "root")  Cannot create PoolableConnectionFactory  (FATAL: password authentication failed for user "root")  FATAL: password authentication failed for user "root"  So I am in trouble, I do not understand why I am getting this. Is it because I remove the container? I was thinking that I must get my data because there is a volume option in docker-compose file for my system? So can I fix everything if I copy data from another container?


I want to use a BLUETOOTH I added this in manifest   <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" /> <uses-permission android:name="android.permission.BLUETOOTH" />   next I did this :  String uid = "0000111f-0000-1000-8000-00805f9b34fb";     UUID uuid = UUID.fromString(uid.toUpperCase()); //Standard SerialPortService ID     mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);     mmSocket.connect();     mmOutputStream = mmSocket.getOutputStream();     mmInputStream = mmSocket.getInputStream();   but here ;  mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid);   I have this Error     va.lang.NullPointerException: Attempt to invoke virtual method   'android.bluetooth.BluetoothSocket  on a null object reference


I am an undergraduate student from Bangladesh. Two of my posters have been accepted at Sigmod undergraduate research poster competition.  Now, I am looking forward to attend Sigmod. I will be receiving some travel grant from Sigmod to attend the event. However, the fund seems insufficient as the airfare from my country to US is very high.  Is there any external source where I can apply for travel grants or support of similar kind?  I am determined about attending Sigmod and I will be paying the rest of the costs by myself. So it would be really helpful for me if I get some support.   N.B. : I have already seen the post . However, I believe I need some more concrete answers. Thank you for understanding.  I have already asked the chairs for student volunteering and others. In this case, SIG and conference funding is basically the same. So I do not have the option to apply for SIGs.


I've written a $_GET query that passes strings on from a URL to a select query used to find information in MySQL.  The problem is, unless the URL query includes quotation marks, it won't work.  Is there any way to pass a string without the quotation marks ?  Here's the relevant code:    $query = $_GET['query'];  connect to database code..  $sql = "SELECT * FROM table1 WHERE col1 RLIKE $query";  result code ...


Textbook recommendations for self-studying high school math?

I'm a high school student who is trying to figure out a complete course of self-study for each year of high school. How can I self-learn grades of math without devoting too much time? This is a complex issue for me, as other students at my competitive high school have tutors and the like. Please recommend textbooks that have detailed explanations and progressive practice problems, for self-study for each area such as:  Algebra  Geometry  Trigonometry and Analytic Algebra  Pre-calculus  BC Calculus  Other people have skipped grades of math due to help from tutors and parents. Can I cover all of geometry and trigonometry in 8 months without going insane and be able to skip a grade?


Generalizing results - what is the population?

Take as an example the well-known . In the original paper, the regression model was used to model the amount people were willing to pay for improved air quality.  But the 'people' whose behaviour was being modelled was never specified. Presumably, it was not limited to 'residents of Greater Boston'. Only implausibly would it be 'humans anywhere on the planet'. Nor, 'all US residents'.   So what inference are we invited by the authors to draw about the scope they intend for their theory? Perhaps 'all residents of large US metro areas'. But - what about other First World metro areas? The first two sections of the Boston paper scrupulously avoid any reference which might suggest that they had a particular 'population' to which their 'sample' was to apply.  There is also the dimension of time - the data came from the 70s, whereas the theory is has no time limitations spelt out.  Plus - going back to first principles - how could the Boston data be treated as a sample of a population including, say, the Chicago metro area when no data from the Chicago area was considered?   Besides, lots of the covariates in the Boston regression weren't samples at all, but totals - so, for example, the proportion of blacks was supplied from census stats.  My question: how can we conceive the Boston data as supporting the geographically unlimited propositions in the paper? Is there a mathematical way of showing equivalence or approximation of the Boston data analysis to other cities? Or is it just assumed as a matter of common sense - such that the paper's authors would be amazed to think anyone could have any doubts on the matter?


Can't find any tutorials on Body Edgeloops

I can find plenty of tutorials on good edge loops while modelling the head, hands, feet but nothing on the main body itself, any help please?


Why is the inserted image not between the paragraphs?

In the following code , I have 2 paragraphs with an Image between para 1 and para 2. As written in the code. The figure code is between the paragraphs text. But in the pdf file output the image does not lie between the paragraphs but at the end of the para 2. Can anyone pls help me to get the image between the paragraphs? CODE: \subsubsection{para1}   xxxxxxxxxxxxxxxx  \\  \begin{figure}[h]  \includegraphics[scale=0.8]{RotorAssembly}   \caption{Rotor components and assembly  \label{fig: Permanent magnet rotor }  \end{figure}  \subsubsection{para2} Permanent magnets are made of xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


BibTeX related, searched many posts but couldn't find precise answer

I've perused quite a few posts on here and haven't found a precise answer to this, though there are many similar questions.   I am using TexMaker and trying to produce a list of references at the end of my document. Here's basically what I have:  In file.tex  \documentclass[12pt]{article} \begin{document} text \bibliographystyle{plain} \bibliography{refs} \end{document}   In refs.bib (stolen from another example; my .bib file is exported so I'm fairly certain the syntax is right).   @misc{ Nobody06,    author = "Nobody Jr",    title = "My Article",    year = "2006" }   I have tried several methods of compiling including latex bibtex latex pdflatex pdfViewer, among others. TexMaker finds no errors, but I get warnings at all of my citations: citation  on page # is undefined. A .bbl file is produced, but it is empty (literally no text whatsoever). My .blg file also appears to have no information in it whatsoever. One of the strangest things (IMO) is that TexMaker KNOWS that my citations exist because if I type \cite I get auto completions which match my citations.   I'm pretty new to using LaTeX so I'm don't assume I have tried something obvious, I probably haven't, though I HAVE tried pretty much everything that I found posted online...


I am a bit confused about the derivation of MLE of Uniform$(0,\theta)$.  I understand that $L(\theta)={\theta}^{-n}$ is a decreasing function and to find the MLE we want to maximize the likelihood function.  What is confusing me is that if a function is decreasing, then wouldn't the function be maximized at the smallest input rather than the largest?  Thank you in advance for your help.


I left 2 blocks of cheese from a deli sit in the car overnight, car was hot inside.  I put in fridge right away when found.  Sharp and Baby Swiss.  Is it ok to eat?


I want to junit test on a private class nest into the public class.  public class getData{ ... private class DataInfo {  private String data;  public String getData(){   return data } }  }   Is there a way to test above private class method?


i have added one list like below:  >>> l = [1,2,3,4] >>> len(l) 4   so when i accessed  l[3:1] python has return blank list like []  l[3:1]=4 it returns error like  >>> l[3:1] = 4 Traceback (most recent call last):   File "<stdin>", line 1, in <module> TypeError: can only assign an iterable   but when i used l[3:1] = 'a'. it successfully run and gives new list as below:  >>> l[3:1] = 'a' >>> l [1, 2, 3, 'a', 4] >>>    now i have length of 5. now i want to add new element at 5th index so i write  >>> l[5] = 5 Traceback (most recent call last):   File "<stdin>", line 1, in <module> IndexError: list assignment index out of range >>>    my questions are follow:   why ptyhon returns blank list when accessing like l[3:1]? why it gives error when using l[3:1] = 4 but works fine using l[3:1]='a'? Why it is giving error instead of adding new value at 5th index?


How to print output and stay in the same line (Python)?

I have string that goes over multiple lines leading the terminal to scroll to the latest printed line. But I want to stay in the first line, so that I will be able to see the first lines but not the latest. Is that possible? e.g.:  for i in range(100):     print(f"hello {i}")   and I want to see hello 0 but the output should stay in the same shape


jQuery accessibility with PHP GET parameters

This has been in my mind for a long while now and I can't seem to figure it out myself. Neither do I find any useful information about this, out there, so I hope to get some answers here instead.  I'm using jQuery which is integrated into my site, together with a lot of PHP GET parameters to control what content you're watching. However jQuery doesn't seem to be available when code inside an if-block with a GET parameter tries to reach it.  Example PHP:  if($_GET["page"]) {     echo "
Click me
"; }   Example jQuery:  $(".box").click(function() {     alert("Box!"); });   When you press "Click me", nothing would happen, as it the jQuery code doesn't exist. Why is this happening and is there any workarounds for this?


How many steps are there actually on the path to High Hrothgar

The title says it all.  It is mentioned several times that there are 7000 steps on the path to High Hrothgar. Are there actually 7000 steps or are the NPCs exaggerating?


I'm looking at upgrading my 95 MB/s SD card to a UDMA 7 CF on my 5D mk II; however, I know that eventually I'll hit an internal hardware bottle neck (after all the processor can't spit out images at an infinite rate).  Instead of asking specifically about my camera, how would I find that threshold where adding a faster card wouldn't make the camera any faster?


For beta sites exclusively, the opened achievements tab will be overlapped by the "Next Privilege" box on a user's own activity page:    The above was took with Language Learning Stack Exchange open though I have reproduced in:   Retrocomputing Stack Exchange (beta) Coffee Stack Exchange (beta) PPCG (beta)   Can we not have the next privilege overlapping the Achievements tab (when opened)?


I'm trying to understand how the Gibbs sampling algorithm works. I've simplified it into a bivariate case to help my understanding but I'm unsure how to go from conditioning on $X^{t-1},Y^{t-1},X^t$ to $Y^{t-1},X^t$.     Lets say we want to sample from $f_{X,Y}$ but we only have access to $f_{X|Y}$ and $f_{Y|X}$.  We construct a transition kernel that generates samples from our joint distribution;  $\begin{align*} K((x^{t-1},y^{t-1}),(x^t,y^t))= f_{X^t,Y^t|X^{t-1},Y^{t-1}}  &= f_{Y^t|X^{t-1},Y^{t-1},X^t}\cdot f_{X^t|X^{t-1},Y^{t-1}}\\&\ldots \\ &= f_{Y^t|Y^{t-1},X^t}\cdot f_{X^t|X^{t-1},Y^{t-1}} \end{align*}$


What would be the best way to describe the non-standard syntax of "The spider he was confused."?


Why is the area under the ROC curve better than raw accuracy as an out-of- sample evaluation metric?


This is a kind of follow-up of my previous Phys.SE question   that seems to have established that, for an outside observer, things never fall into the black hole. Note that this is not to say that an outside observer never sees anything falling into a black hole (as in receiving the optical signal), but it is instead an stronger statement: no matter how long an outside observer wait for anything to fall into a black hole, there will always exist intersection between his own future light cone and the in-falling object's light cone outside the event horizon. That is what I mean by "things never fall into the black hole".  Assume an initial universe with no black holes (stellar or primordials), and thus, has no event horizons. Is there a solution to GR equations showing that the light cone of any amount of mass will inevitably reach a singularity, never intersecting with the light cone of an observer outside the would-be-black-hole? For my understanding, the Schwazschild metric describes an eternal, static, black hole, so I guess I am looking for something else here.  Please notice that I tried to be much more specific than the other questions about black hole formation, because the answers saying that in falling observers would reach the singularity in a finite amount of proper time isn't really helping me to understand the phenomenon from an outside perspective.


How should a question which quotes a question be punctuated?

Suppose there is a sentence in question form, like the one appearing below:     Where do you belong to?   Now, if a speaker refers to that question, he will frame another sentence and will place the question in the quotation marks in that sentence, like what is appearing below:     They said, "Where do you belong to?"   Now, if the speaker wants to convert this sentence too in question form, he will put the original question in another question, like what is appearing below:     What did they mean by saying "Where do you belong to?"   Now, if the speaker wants to rephrase this sentence, it would become as follows:     By saying "Where do you belong to?" what did they mean?    My question is how the 4th sentence is to be punctuated. It has two question marks in it. Does the sentence correctly take two question marks? If so, why will the 3rd sentence not take two question marks − one, just before the closing inverted commas and, the second, just after those commas? The 4th sentence and the 3rd sentence are all same, except being a bit different in placement of the words. Will they take two different sets of punctuation marks?


Why is it "I did that wrong" instead of "I did that wrongly"?

It seems that "in a manner such that it is wrong" should be "wrongly", not just "wrong"...


I have a big problem my render F12 is all white, while my preview render is working.  Please help me guys, thanks.


This is a subset of my question earlier about how some questions survive while others exist, despite seeking legal advice that is clearly personal to them. I've decided if that is the law of the land, and people want to cast votes to close, I'm on board. Today, I ran across a couple questions of this type. One new user wrote a question, and with posting it, also posted a bounty. The Q is a clear plea for legal advice. The person, having come from another SE community had enough reputation to post a bounty, unlike other new uses, which prevents it from being closed.  My question is, why does the existence of a bounty shield a question from closure?


image of adjoint equals orthogonal complement of kernel

Let $T:V\to W$ be a linear map of finite-dimensional spaces.  Then $${\rm im}(T^{\textstyle*})=({\rm ker}\,T)^\perp\ .\tag{$*$}$$ I can prove this as follows: $${\rm ker}(T^{\textstyle*})=({\rm im}\,T)^\perp\tag{$**$}$$ is quite easy, and we know $T^{\textstyle*}{}^{\textstyle*}=T$ and $W^{\perp\perp}=W$, so $${\rm im}(T^{\textstyle*})=({\rm im}\,T^{\textstyle*})^{\perp\perp}=({\rm ker}\,T^{\textstyle*}{}^{\textstyle*})^\perp=({\rm ker}\,T)^\perp\ .$$ However, I would be interested in a "direct" proof of $(*)$.  It's fairly easy to show ${\rm LHS}\subseteq{\rm RHS}$.  For the converse I have tried obvious things but seem to be going round in circles.  Also, any insights as to why $(**)$ is harder than $(*)$ - if in fact it is :)  Edit.  To clarify, I am considering the adjoint defined in terms of an inner product, $$\langle\,T({\bf v})\mid{\bf w}\,\rangle   =\langle\,{\bf v}\mid T^{\textstyle*}({\bf w})\,\rangle\ .$$


The task is to find all ideals of ${\mathbb{Z}_n}$, where $n$ is   positive integer, greater than one.   My effort  Let $I$ be an ideal of ${\mathbb{Z}_n}$. It is obvious that $I$ is an additive subgroup of ${\mathbb{Z}_n}$. Consider $G$ as an additive subgroup of ${\mathbb{Z}_n}$. Then $G$ is a cyclic additive subgroup generated by $\left\langle d \right\rangle $, where $d \mid n$. We know that for a finite cyclic group of order $k$, every subgroup's order is a divisor of $k$, and there is exactly one subgroup for each divisor. It follows that all ideals of ${\mathbb{Z}_n}$ are of form $\left\langle {{d_1}} \right\rangle ,\left\langle {{d_2}} \right\rangle , \ldots \left\langle {{d_i}} \right\rangle $, where ${d_1},{d_2}, \ldots ,{d_i}$ are positive divisors or $n$.   Questions  Is my proof correct?


How to search only unanswered questions with an open bounty ?

Is there a way to search only unanswered questions with an open bounty on StackOverflow ?


What is the exact difficulty in defining a point in Euclidean geometry?

In Euclidean geometry texts, it is always mentioned that point is undefined, it can only be described. Consider the following definition: "A point is a mathematical object with no shape and size." I do not understand what is the problem with this definition. Please give the detailed reasons. Thanks in advance!


Can we determine if a complex number is greater than another?

Is it possible to determine if one complex number is greater than another? Or as the question implies is there an "order" to complex numbers (like 1 is before 2 in the real numbers)?  I thought that would could simply use the modulus to determine if one complex numbers is greater than another, though I believe this can't be the only way used (what if 2 complex numbers have the same modulus  and are quite different). So I thought, if the point is in the uppermost right quadrant of the complex plane, then both real and imaginary parts are positive, so it would be greater than any other complex number in a different quadrant of the complex plane (you might say what about the modulus, but in the reals $1>-2$ even though $|-2|>|1|$). But what if one complex number has a positive real, and negative imaginary and another one has a negative real and positive imaginary? (And for arguments sake they both have the same modulus)  If we can't determine why not? In the real numbers it seems (to me), quit trivial at a basic level to determine if one real is greater than another e.g. $2>1$. What is this property of numbers called? Why doesn't complex numbers exhibit this property (if indeed it doesn't)?


I'm not sure if it's proper to ask this question on Stack Overflow itself, but I'm really eager to find a good Stack Overflow app for my iPhone and Android phone, so I can login to my Stack Overflow and ask/answer questions. I tried a few but none is perfect, some can't support iOS 7 perfectly, others don't support login. Can anyone help?


Keep getting "sudo: unable to resolve host"

Everytime I type in sudo it says that after it. I tried following others instructions, but it says bash: /etc/host: permission denied.


Is the maximum degree of a planar graph 5?

I'm trying to study (by myself) planar graphs. On the book I'm reading, I came across this sentence about the 5-coloring problem that I really don't understand:  Lemma 5.8.15. Every planar graph has a vertex of degree at most five. Proof. By contradiction. If every vertex had degree at least 6, then the sum of the vertex degrees is at least 6v, but since the sum of the vertex degrees equals 2e, by the Handshake Lemma (Lemma 5.2.1), we have e  3v contradicting the fact that e  3v <= 6 < 3v by Theorem 5.8.6.  I don't get why a planar graph has a vertex of degree at most five. If I take the 9-star graph there will be a node with degree 9 and the graph will still be planar so the maximum degree is greater than 6. Can anyone explain this to me? Thank you.


How can I link to a specific section/part to a specific answer on a specific page?

I was able to add  name-link inside (or top-of) the section related to "Setup Java Environment Variable" in my own answer. My answer post is a bit longer, and this "JavaEnvVar" section is located in much bottom side. When I'm writing an answer for another question, I want to show a specific link into that specific bottom-side section "JavaEnvVar" in my own long answer. How can I do this? See this LONG  (I used this link https://stackoverflow.com/a/62874205/3553808 in above line, to link into the specific answer, this link was obtained from the "Share" option/button which is shown at bottom side of that answer) In my long answer, the line which has "Java ENV-VAR (ENVIRONMENT VARIABLE)" is the "JavaEnvVar" section, that has the name-link which I displayed here in the top/first line of this post/question. I want to reach that "JavaEnvVar" section quickly, to show only the specific instructions related to How to setup JAVA_HOME ENV VAR (which was created by me with some specifics), and then it will be easy for a user to find it & understand it. I'm trying to use such link (to specific-section of a answer), into my another answer . I have tried to use this https://stackoverflow.com/a/62874205/3553808#JavaEnvVar, but that does not work! it goes into top/beginning of my answer. I created a DIV such as this:
SECTION-NAME:
 but that also does not work, the Stack... parser removes it! So it seems (after using Firefox > main-menu > Tools > Web Developer > Inspector ) that Stack Exchange / Stack Overflow parser is removing the  name-link from that section in the webpage HTML code! But when I use "Edit", then src of answer still shows the name-link.


Is the double boiling canning procedure really necessary?

It seems the usual procedure is to sanitize cans and lids by immersing them in boiling water, to fill the cans, and then to cap them and boil for a few more minutes.  If I sanitize a can and then fill it with boiling jam, and cap it with a sanitized lid, then why bother with the extra boiling?   It seems like a totally redundant step.  Conversely, if you are going to immerse the filled cans in boiling water to process them, then why bother pre-sanitizing them?  This makes no sense!


Sound Problem - No Audio Input is Shown i.e Microphone is not Visible. Neigher "Headphone" profile is available?

Sound Problem - No Audio Input is Shown i.e Microphone is not Visible ,neither the "Headphone" profile is available !  I have Headphone connected and I can hear voices coming out of it !  I suspect Cadence or GLadish is responsible for this  ! Please help. I also suspect resetting all audio related settings to back to its factory state will solve this issue !! But I dont know how to do that !?


LWC: How do I display "out of box" object hover?

When you hover over an Account name link on standard views, a popup with the Compact Layout shows the details of that record.  Is it possible to do this using Lightning Web Components?  Perhaps using the output from getRecordUi?  I cannot find any examples online of how to use the results from getRecordUi - how can that be converted to a page layout to display to the user?    Some related links that I found, but did not have answers:


My computer is always freezing, how do I fix it?

I am using a Dell Latitude E6500 on Ubuntu 16.04 with 2GB RAM.  The computer freezes often when running firefox and even running python.  Should I use a lighter OS like Lubuntu or are there any changes like swap RAM or eliminating unneeded programs that can free up some RAM? When i first start the computer it runs at less that 1 GB RAM.


Using modules and webpack for JS project: Why am I getting an `Uncaught ReferenceError`

I'm working in modules with webpack and in order to avoid creating variables in the global scope, I did this Revealing Module Pattern: function establishArrays() {      let globalVar = (function () {         let projectList = [];         return {             projectList: projectList         };     }()); };  export default establishArrays;  If I put console.log(globalVar.projectList) in the function, it works when run, showing [] Now establishArrays is part of a file index.js into which is imported renderProject as well. However, when I do this, function renderProject() {   console.log(globalVar.projectList) }  I get this error, Uncaught ReferenceError: globalVar is not defined at main.js:2 What could be causing this? In index.js I have imported and run them: import createUUID from './UUID'; import establishArrays from './establishArrays'; import createProjectListeners from './createProjectListeners'; import renderProject from './renderProject';  createUUID(); establishArrays(); createProjectListeners(); renderProject();  Thanks!


Knowing that $a_n \rightarrow a$ and $b_n=\frac{a_1+a_2+...+a_n}{n}$. How can I show that $b_n \rightarrow a$?


I hear about "" all the time, but don't know what it is.     What is it's purpose?  Why do I need it? What problems does it solve? What problems does it create?


What happened to Red Skull at the end of Captain America - The First Avenger?

At the end of Captain America - The First Avenger, when Red Skull and Captain America are fighting on a plane, Red Skull holds the Tesseract in his hands. And soon a portal opens to another space dimension and the Red Skull disintegrates due to the power of the Tesseract.     Did the Red Skull actually die or was he sucked to another space dimension? Because the Tesseract is later revealed to be a Space Infinity Stone


How to create a simple button for a script?

I'm struggling trying to create a simple button for this script:  for Nlys in (3,8,11,13,16,5):     bpy.context.object.data.layers[Nlys] = True  for Nlys in (0,1,2,4,7,10,14,17,9,12,15,18,6,20,5,19,28):     bpy.context.object.data.layers[Nlys] = False   In Maya I was used to drag an drop the code into a shelf and the button was created automatically.  Is there a way to to this in Blender?    Update:  helped me to figure out a solution for this result.


If f is concave upward on [a,b], then is average value of f more than f(a+b/2)?

I'm trying to solve a question concerning about average value of function. A problem is  If $f$ is concave upward on $[a,b]$, then $\frac{1}{b-a}\int_a^bf(x)dx > f((a+b)/2)$  I understand why it is true using diagram but I can't prove it. I'm trying to use the fact f is concave upward so $f'$ is increasing but I couldn't go any further.  Thank you in advance!


Why won't my secondhand iPad let me activate an Apple ID?

On the settings under iCloud, if I try and log in on the ID I created this morning, it says that the maximum number of ID's have been activated on this device. When I try and create a new account underneath, it says that this device is not eligible for one.  How can I resolve this?


I am looping over a feature in Arcpy and doing several geoProcessing tasks on each feature/iteration.   The loop runs pretty well but crashes on some of the features. I dont really know why but its probably because of some geometry error or something weird.     I can see what files have been output along the way so I can simply restart the loop and bypass the bad feature.  If I could somehow detect a runtime error like above, I could restart the loop and bypass the bad features. Is there any way to fire a function on a Runtime Error event?


It slowly dawns on me, after several years of using the SE network, that it doesn't do the obvious: present questions to me where I might be of maximum value. Specifically:   Questions on any of the SE sites that I'm a member of That are at risk of going unanswered (ie, not minutes-old questions that will likely be answered by someone else) That match my expertise (based on favourite tags, or tags of questions I've answered) With a bias to higher rated questions   SE seems good at pointing me at "hot" questions (ie, ones with many answers), or all "unanswered" questions (regardless of whether they're relevant, or even answerable). This seems very inefficient from the perspective of maximising the number of answered questions (rather than maximising total number of answers).  Am I missing a feature somewhere? If so, are others missing it too?


Call static (async) method with generic type constraint, with type name (string)

I need to call a static method (of a helper class) which has a generic type constraint like this:  public static ResultType SomeMethod<T>(string someParm)      where T : SomeBaseClass   How can I call this method if I only know T by its name (string)?   I have seen , but I could not figure out how to use  in my case.  UPDATE  After this was flagged as duplicate, I realised I should have asked if the static method is an async method with optional parameters.  public async static Task<ResultType> SomeMethod<T>(string someParm,      string optionalParm) where T : SomeBaseClass   Then I found this answer: . Basically, invoking an async method would return what you expect it to return, which is generally either a Task or Task<>. Bleeding obvious now, LOL   Then, I was getting Parameter mismatch count. It turned out I had to provide all parameters, and specify Type.Missing for optional parameters where I want the method to use the default value.


I have just installed Ubuntu and it's great. I  also installed Flash by following .  After I wanted to download a video from Youtube and I installed a software called Miro that looks like some sort of browser. When i navigated to Youtube it says no Flash Player downloaded. But if I use Firefox, Youtube  works fine. Help pls


I'm using TeXLive 2014 on FreeBSD. Every LaTeX-files produce the following warning:   LaTeX Warning: Please use \usepackage[latin2]{inputenc} with            \usepackage[magyar]{babel}.   "Magyar" is the name of the hungarian in hungarian language :)  The relevant part of my documents:  \documentclass[a4paper]{article} \usepackage[magyar]{babel} \usepackage[utf8]{inputenc} \usepackage{t1enc} \begin{document} Árvíztűrő tükörfúrógép. \end{document}   Can I skip this warning or should do something to fix it? Or maybe it's a bug?  Before TeXLive 2014 this warning didn't appear.


Adding custom input field in menu backend

How can I add the custom content in the menu items in the back-end. For example I want to add another input field and save it. I could not find any information in the Codex.


Should I include a publication where I'm only acknowledged (and not one of the authors) in my CV?

Suppose that I've helped other researchers with the statistical analyses for an epidemiological study and therefore I am acknowledged for that in the "Acknowledgments" section of the paper (something like "We thank andrea for his statistical support").  Obviously, this doesn't count as a publication for me, as I am not one of the authors. But if I include it in my CV, how much "weight" would a professor (or someone within the academia) give to that? I also have other publications where I am either the first author or one of the co-authors.  I am not thinking of a particular situation here (like applying for a grant or for a PhD position). I am just curious to know if it could be useful to put it into my CV or if it would just be irrelevant.


how many bytes does a string object in memory,contains the object header?

As i know,a Java object contains object header,reference and it's data.  //jdk 1.7 public final class String{        private final char value[];        private int hash;        //...     }   For new String("abc") ,how many bytes will it take if we just think about 32-bit system?  totleBytes =      8//String Object header     +4 //value reference      +4 //hash     +12 //char[] object header     +3*1//value[] data   does it right,or miss something?


I am wondering how to prove both of this by induction: $1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+\cdots+\frac{1}{2^n}\leq 1+\frac{n}{2}$ In general, how should I think of how to prove such an inductive step for these types of inequalities? If there is any other way to prove please feel free. Any help would be appreciated.


I'm a beginner with JAVA so this question is not making much sense:     Write a method called append that accepts two integer arrays as   parameters and returns a new array that contains the result of   appending the second array's values at the end of the first array. For   example, if arrays list1 and list2 store {2, 4, 6} and {1, 2, 3, 4, 5}   respectively, the call of append(list1, list2) should return a new   array containing {2, 4, 6, 1, 2, 3, 4, 5}. If the call instead had   been append(list2, list1), the method would return an array containing   {1, 2, 3, 4, 5, 2, 4, 6}   Help is greatly appreciated. Thanks.


Should the site prompt new users to include an @name in comments?

Lots of the first questions come with insufficient information, context and eventually left unanswered after days.  While other users comment below requesting more info, the inexperienced OP usually reply without @ believing it works exactly the same as facebook, but no one receives notification.   One or two days later, the OP feels really lost on the site, and convinced his/her question is so hard to be solved or the people on the site just trend to ignore him/her.  A little extreme example today on stackoverflow, a user deleted the question posted yesterday, and posted again to get other's attention. Simply because no one being notified.   Current  will notify other users when OP missed @ in such cases:   OP comment on an answer, the author of the answer will be notified. (not applicable, as most unnotified comments are under the question.) OP comment under his own post, and exactly one person commented. (not applicable in most cases, as a fuzzy question usually start a little discussion below.)   Which means basically, there won't be any notification for previous people who commented.   So is it possible to enforce (at least shows a tip) the new user comment with a @ in their first few comments?


These popups are in my screen from the day I bought my POCO M2 and they last for long time. And when I am doing something else they come in between. They interfare while typing and selecting options. Moreover, they are annoying. Anyone has idea??


What is it called when someone says something like: "I'm not a racist, but..."

Other examples are:      I'm not sexist but (sexist comment)      Not to be a dick, but (dick comment)      No offense, but (offensive comment)   And so on... where they are trying to excuse themselves from what they are about to say?  What is the name of these kinds of statements?


References to learn how to efficiently use neural networks for time series prediction (textbooks, online courses, etc.)

Is there any educational material that focuses on introducing neural networks for time series prediction, ideally comparing to traditional models?  It is ok if the references assume the reader knows about neural networks: I am only interested in how to efficiently apply them to time series prediction.  I would prefer some modern material (e.g., something that goes beyond :   )  I am  of  the typical references for learning neural networks in general, as well as neural networks applied to natural image processing and computer vision.      Some textbooks I looked at:   {1} Montgomery, Douglas C., Cheryl L. Jennings, and Murat Kulahci. Introduction to time series analysis and forecasting. John Wiley & Sons, 2015. --> only has three pages on neural networks.


I want to to my RaspBerry Pi 4 with an old small CPU fan. However it's a 12V fan. Is it possible to use 2 of the 5V pins on the board to total to 10V? Sorry if this is a dumb question. I haven't worked with electronics in a while.


How sharply does the wavefunction collapse upon measuring position?

It cannot be a Dirac delta as this is not a continuous normalisable function. Further to the answer written by John Rennie  We may assume that the collapse is not perfect. In this case, how is the quantum formalism applied to calculate the probability of this measurement? One solution to this is to discretise the continuous operator as a function of position. The eigenstates are then degenerate and we will have a non zero probability of measurement. However, is it necessarily true that the resulting collapse will be a projection of the wavefunction? Can it not be 'reset' to a simpler distribution, for example Gaussian?


Please add specific close reasons to the review queue on Meta

The review queues on Meta provide the highest level close reason. If a user closes a question with the reason:     The problem described here can no longer be reproduced. Changes to the system or to the circumstances affecting the asker have rendered it obsolete. If you encounter a similar problem, please post a new question.   which falls under the "off topic" section, but is also about the Stack Exchange network. The close reason shows up in review as:     off-topic: This question does not appear to be about Stack Overflow or the software that powers the Stack Exchange network within the scope defined in the help center.   In the case of , which just showed up in the queue, this is extremely confusing. The question is specifically about the Stack Exchange network, should be closed, and should be closed with the reason the original voter selected, but not the reason the reviewer sees.  Take a look . I'm sure Lance Roberts and Richard Tingle were well-meaning, but they likely also read this the wrong way, as the question should clearly have been closed with the given reason.  In order to figure out what the real close vote is, I would need to go through the menu and check, or go to the question and check.  This is somewhat related to the question about the misuse of "off topic" in review reasons, though I can't seem to find that question at the moment.  Could the close reasons displayed please be changed to match the actual close reason selected?  (Also, if this happens on all sites, please let me know so I can make this a generic question instead of a Meta-specific one.)


Why can variance be estimated from a sample taken from an alternative hypothesis?

This is a new question going off . Let's say we have the following scenario:      A neurologist is testing the effect of a drug on response time by injecting 100 rats with a unit dose of the drug, subjecting each to neurological stimulus, and recording its response time. The neurologist knows that the mean response time for rats not injected with the drug is 1.2 seconds. The mean of the 100 injected rats' response times is 1.05 seconds with a sample standard deviation of 0.5 seconds. Do you think that the drug has an effect on response time?   When we do this, we assume the sample standard deviation is equal to our population standard deviation. However, from what I see, this 1.05 sample is not necessarily a sample from our population. This 1.05 measurement is a sample taken from a population that might have a standard deviation that's completely different from the null hypothesis population. For example, what if this drug made all the rats have a response time clustered very closely around 1.05. This means the standard deviation of the population who took the drug would be less than the standard deviation of the population who didn't take the drug.  Because we're not necessarily sampling from the same population distribution, how can we use the sample distribution to estimate another population distribution?   The only explanation I can think of is that we have to assume our drug has no effect, assuming the null hypothesis, and then it would be sampling from the distribution under the null hypotehsis. I get that. But if the null hypothesis is FALSE and there really IS a difference, you'd be sampling from a different population (distribution under the alternative hypothesis), but we still ASSUME it's from the distribution under the null hypothesis, and that's what I can't understand.


No icons for automounted volumes on GNOME / Nautilius desktop on Ubuntu 19.04

Up to Ubuntu 18.04, using default GNOME/Nautilius desktop, when I inserted a (data file) USB stick it would automount and put a USB icon onto the desktop.  I find this very useful, especially for quick eject via context menu.  Now at 19.04, on USB insertion I do see a "banner" appear for a few seconds, but I no longer get any desktop icon .  I run under VirtualBox on Windows, but that has not changed and I do not think is at issue.  Ubuntu does still automount the stick at /media/<username>.  I found .  I checked in dconf-editor and both keys, including org.gnome.desktop.media-handling.automount-open, are set.


Adobe flash download button redirects me to main site

I want to update my flash version to 11.9.900.170. Firefox's check for plugin updates redirects me to   If i click on Install Now i am redirected to www.adobe.com without a download.  How can this be fixed for future updates?  I am searching for a direct download from another server then adobes' at the moment.


Field extension $\mathbb{F}_p(X^p,Y^p)\subset\mathbb{F}_p(X,Y)$ not a primitive extension

How do I prove that $\mathbb{F}_p(X^p,Y^p)\subset\mathbb{F}_p(X,Y)$ is not a primitive extension?  And how can I give infinitely many fields $E$ such that $\mathbb{F}_p(X^p,Y^p)\subset E\subset\mathbb{F}_p(X,Y)$?


I'm using an image for the background, but I only see a blue sky and not the clouds in the bottom of the image near the horizon. It feels like the background image is too close? And in the world tab the preview is just blue. Should I not see the clouds also?  If I create a scen that are 10x10 meter or 100x100 meter or 1000x1000 meter in size, how does Blender set the correct scale or distance between the scene and the background?  I can rotate the background, but can't find any clouds. And I have tested different settings in the Environment Texture node, but all I can see is blue background or very close to the sun. I get this problem often with this type of images, and I don't know what I am doing wrong? Have I missed some kind of settings?  Other types of hdri images, that look spherical, I have no problem with. But this image looks more ordinary. Preciate some help!


Can we do PITR of one specific PostgreSQL database

I am new to PostgreSQL, so please ignore if my question sounds stupid. Imagine we have three databases in PostgreSQL and someone mistakenly ran a TRUNCATE command an hour ago on one of the databases. Now we want to do a PITR for that database alone, since there is an issue with only one database. Is it possible in PostgreSQL to do PITR for one specific database OR it can happen only at instance level? I read the documentation for . It looks like it can only be done at instance level (I guess we say instance as "Database Cluster" in PostgreSQL world, I come from SQL Server world).  As with the plain file-system-backup technique, this method can only support restoration of an entire database cluster, not a subset.  If PITR is not possible at DB level, then how Prod DBAs are handling this situation? Also one last thing, I have a test server with multiple DBs and if PITR is possible at DB level, then please share me the steps so that I can test it myself. I am mainly interested in supported versions of Postgres. My test server is PostgreSQL 9.6.16.


Where can I find historical flight stats?

I'm looking for some old flight stats as Flightaware provides me for the last 4 months. However, I'm looking for flights from the past 5 years. Is there any database that is capable of doing so?  For example, I'm interested in KLM1964 on January 5, 2012.  Specifically, statistics including departure/arrival times, and aircraft type.


Select All function not working properly in jquery

I have a search bar and a table below it which has a select all option. The Select All function works fine but when I search something in the search bar and then Click on the Select All button, nothing happens. I am not able to figure out why is it so?  Here is my code for Select All function      function selectUnselectchkAllProcessedOrders() {     debugger     $("#chkAllProcessedOrders").click(function () {         var checked_status = this.checked;         $("input[name='fulfillmentOrderId']").each(function () {             this.checked = checked_status;              if (checked_status)                 $(this).parent().parent().addClass('greanBackGround');             else                 $(this).parent().parent().removeClass('greanBackGround');         });      }); }   when i click the Select All checkbox after clicking the search button, i can see using debugger that when the selectUnselectchkAllProcessedOrders() function is called, this.checked is undefined.  Here is the cshtml

                                      Order Number	                                      <input type="text" id="TextBoxFullFillmentOrderNumber"  />	                                      <input type="submit" name="ButtonSearch" value="Search"  />                     <input type="hidden" name="posearchorderno"  id="posearchorderno" />                     <input type="hidden" name="search" value="some" />

     }


Conservation Laws and time-reversal symmetry

In most dynamics books I've read they refer to conservation laws and their associated symmetries, cf. . I know that   the conservation of momentum is a result of the homogenity of space angular momentum is the result of isotropic space  and the conservation of energy is the result of the homogenity of time.   Is there a fourth conservation law that would result from time-reversal symmetry?


worksheet problem...Prove the set of all subsets of N is countably infinite

Prove that the set of all finite subsets of $\mathbb{N}$ is countably infinite.  I understand what countably infinite means but I don't know how to arrange the subsets according to their sum and I can't figure out how to form the proof Please help  thanks


Generate all possible variable values in Python

What is the most pythonic way of getting the following:  (False, False, False) (False, False, True) (False, True, False) (False, True, True) ...   I have n variables, each taking a value True or False, how can I combine these? I was thinking of using range(n) and then checking the bits of generated integers, but this seems too hacky.


When I try,  user@user-OptiPlex-7010:~$ sudo apt-get install gcc    I got response as,  Reading package lists... Done Building dependency tree        Reading state information... Done gcc is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.


Gave up waiting for root device on Ubuntu

I've just installed Ubuntu 12.10 to dual boot with Windows 8, but every time I choose Ubuntu from grub menu, it always get stuck at this error and won't boot:  Gave up waiting for root device. Common problems:  - Boot args (cat /proc/cmdline)    - Check rootdelay= (did the system wait long enough?)    - Check root= (did the system wait for the right device?)  - Missing modules (cat /proc/modules; ls /dev) ALERT! /dev/disk/by-uuid/920903aa-762f-40d2-8126-87f4b0e6f975 does not exist. Dropping to a shell!  BusyBox v1.19.3 (Ubuntu 1:1.10.3-7ubuntu1.1) built-in shell (ash) Enter 'help' for a lost of built-in commands. (initramfs)   I tried with boot-repair, but it doesn't help, .


Could we please clarify just the Primary phase of the election?

Has a lot of info about the election process here on StackOverFlow  The first  phase of the election process ("nomination") is pretty obvious.  The last phase of the process (the actual voting) is pretty obvious.  The middle phase, "The Primary" is confusing. I didn't really comprehend the full details of what is acceptable and unacceptable voting during this phase.  This year, The elections page for the primary phase says there are 30 candidates to fill 3 positions.  Of the 30 candidates, I thought that 7 of them wrote the most sensible presentations, so I upvoted those 7.  Is that okay? Do I need to limit my votes to 3 at this stage?  Some of my favorite guys are clearly not going to win (which is okay). I just want to make sure that it's okay to "vote" for more than the number of open positions.  I also notice that just about every candidate gets "yes" and "no" votes.  Should I vote down a candidate whom I think would act in ways that are contrary to my beliefs and thoughts?


So here goes the problem :   Compute:  2^1234 (mod 11)   How would I go about trying to solve this ?   This is what I have tried so far      I know that 2^10 (mod 11) is congruent to 1,but that is about it.


Can there be rate of change of force or rate of rate of change of force?

Is there a rate of change force?          I know that net force is rate of change of momentum or mass *acceleration.  But is there rate of change of force or (mass * jerk) ? or Rate of rate of change of force(mass *jounce)  How to relate them to the physical world? Is it even physically possible?  Assuming mass to be constant


I want to retrieve my Gmail account. I used it 2 year before, 2 year before some security problem happened suddenly Gmail account blocked, I can't use Gmail account up-to now.  I tried to create same username, account creation not accepting, its showing username already exits. Actually I want that username,even data is deleted also no problem.