I killed all my NPCs (including the Goblin Tinkerer), but after a while I have not gotten any messages saying "(NPC Name) would like to settle down." The only NPCs that move back into my tree home are:  Nurse  Arms Dealer  Guide  Merchant Nobody else moves back in. Please help! It's been one day now!

I read on the wiki that people will move in under the following conditions:   You do something to please them An empty house is available with a light source, table, and chair (also with walls).   I have a house which is about 7x8, then a roof space above that; about half the area. I could put furniture up there too, but will anyone move in?


I have two Excel files, with customer data. I need to compare the two.   I have copied the username column from both into a new sheet. Now I want to go through, and if the username is in the first column and the second, ignore that record. So I have a list of only the unique usernames.  The lists are not in any order, so I cannot just compare each column depending on row, I need to compare one cell, to all the cells in the other column, all the way through.  Is this even possible? I have never used Excel before.

I would like to compare two Excel spreadsheets  Both have the same columns, in the same order, but not the same rows.  I have a spreadsheet with 1,000 rows and 50 columns including a unique ID for each row and personal data (address, phone number, etc.).  I want to compare it with the same base extracted one year ago.  My objective is to know all changes (for example, someone who changed his address).  I tried with spreadsheet (as explained here: ) but it doesn't work because in my "new" file I have new rows, and I have some rows in the old file which are not in the new.  Spreadsheet compare with Excel line number. Is it possible to compare with the first column (Unique ID)?   Here is a very simplified example:    There are two sheets representing my two spreadsheets.  As you can see both have the same columns but:    There are rows that are on both sheets with no changes (all the row is the same)  There are rows that are on both sheets but there are changes (in orange on my example)  There are rows that are only in the December sheet (I don't need to identify these lines)  There are rows that are only in the January sheet (in orange on my example)    The orange color is exactly what I want, but in this example I can do it manually: comparing December and January. In the real spreadsheets I cannot do it manually as there are too many changes, data, lines, columns, etc. and I will do this monthly.   There is only one column which can never change: the column A.


The power set of $\mathbb{N}$, $\mathcal{P}(\mathbb{N})$, is not countable as well as the sets $\mathbb{R}$, and $\{0, 1\}^{\mathbb{N}}$ the set of all sequences which takes values 0 or 1. Use this to show that the set of all irrationals is not countable.   We have the set $\mathcal{E} = (\mathcal{E}_{n}) \in \{0, 1\}^{\mathbb{R}}$ defined by $\mathcal{E}_{n} = 1 - f(n)_{n}$, where $f(n)_{n}$ is the n-term in the sequence $f(n) \in \{ 0, 1\}^{\mathbb{N}}$  We can find a subset of $\mathbb{R}$ to show that $\mathbb{R}$ is not countable:  $$ C = \left \{ \sum_{n=0}^{\infty} \frac{\mathcal{E}_{n}}{3^n}; (\mathcal{E}_{n}) \in \{ 0, 1 \}^{\mathbb{R}} \right \} $$  $C$ is the Cantor triadic set. So, $C$ is a subset of $[0,1] \in \mathbb{R}$, and it is bijection with $\{ 0, 1\}^{\mathbb{N}}$. Hence $\mathbb{R}$ is not countable. Since $\mathbb{R}$ is not countable and $\mathbb{Q}$ is countable, then $\mathbb{R}$ \ $\mathbb{Q}$ is the set of all irrationals and it's not countable since the union of two countable sets is countable.  Now, I'm looking for other solutions to prove it, please comment on

Can someone point me to a proof that the set of irrational numbers is uncountable? I know how to show that the set $\mathbb{Q}$ of rational numbers is countable, but how would you show that the irrationals are uncountable?


I'm trying to make dropdown menu with tailwindCSS   and there is a good example for me :   but i can't recognize where is a hover control, and what is \ mean in CSS.  hope kindly help me.  .group:hover .group-hover\:block {   display: block !important; }

What characters/symbols are allowed within the CSS class selectors? I know that the following characters are invalid, but what characters are valid?  ~ ! @ $ % ^ & * ( ) + = , . / ' ; : " ? > < [ ] \ { } | ` #


Is Stack Overflow open source? If so - where can I get the source code?  If not - I see some people using it:  how did they get it?

Since the source code for this site isn't available for purchase or external use, I'm looking for software that can run a Q&A environment similar to Stack Exchange. Are there any such pieces of software available?


I followed the instructions at  to install Yandex browser.   When I did apt-get update, I got this error:  root@aspire:~# apt-get update E: Malformed line 1 in source list /etc/apt/sources.list.d/yandex-browser.list (URI) E: The list of sources could not be read.   So apparently the  were not quite correct, because I entered the lines into yandex-browser.list as instructed  root@aspire:~# more /etc/apt/sources.list.d/yandex-browser.list deb [arch=amd64] http://repo.yandex.ru/yandex-browser/deb beta main   So, if the problem is the first line, how should I change this? I am guessing I need to remove the [arch=amd64] part, but then will I still get to the right package, as there are both a 32-bit and a 64-bit packate at the repository?

I have unistalled and reinstalled the Ubuntu Software Center as per info I found in a similar thread and I got the same response about line 91 or something like that.  I just tried to upload a screen shot but since I'm new it won't allow me to.  I also can not figure out how to cut and paste anything so I have to hand type what the error screen says, both when I attempt to open the software center and nothing happens, when I try to enter commands into the terminal to uninstall, reinstall, whatever I get the same following:  COULD NOT INTITIALIZE THE PACKAGE INFORMATION An unresolvable problem occured while initializing the package information Please report t:his bug against the 'update-manager' package and include the following error message: 'E: Malformed line 91 in source list/etc/apt/sources.list (dist parse)  E: The list of sources could not be read.,  E: The package list of status file could not be parsed or opened.   How do I report bugs?  What can be done about this.  I have searched and everything everyone says to do leads me back to the same line error message.  So, I don't know how to get to line 91 in the source list; to tell you what it says. Sorry, I'm really new to this. That is what I need is to find out how to get there and fix what it says. I would really like to NOT have to re partition my hard drive and start from scratch, so I'm really looking forward to getting this problem solved. I need to be able to install new software.


Problem  This is an interview question my friend asked me since she messed up with it. To be more specific,     What is the resulting distribution when a Gaussian $\mathcal{N}(\mu, \sigma^2)$ is transformed by Sigmoid $t(x)=\frac{1}{1+e^{-x}}$.   I tried to derive and got the following  $$ \begin{aligned} \log y&=x-\log (1+e^x)\\ x&=\frac{1}{\sqrt{2\pi\sigma}}\exp(-\frac{(x-\mu)^2}{2\sigma^2}) \end{aligned} $$ But the $\log(\cdot)$ seems to be intractable when I plug $x$ in.  I also tried to simulate this process and got    It seems that the resulting distribution is still Gaussian (with some elevation and shrinking in magnitude). But I still would like to know the theoretical derivation.  Could someone help me and my friend? Thank you in advance.

If I have a normal distribution with a given mean and variance and apply a logistic transform to it, what is the mean and variance of my transformed variable?   This seems like it has to be a well known problem, but I haven't been able to find a quick reference anywhere.


I have a String Array called copy. I want to check if copy[0] matches with copy[2] and copy[3]. If it matches, then print something.  I tried using IF statements but i keep getting errors.  public static void main(String[] args) {     String[] copy = {"1","2","1","1","5","6","7","8","9"}; }

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


I'm writing a thesis with \documentclass{report} on Overleaf and I am using the IEEE reference system, that has references as numbers, i.e. [1], [2], [3] etc. According to several reference guides for IEEE (for example the following [],[],[],[]), "Citations are numbered in the order in which they appear in the text". This is however, not what happens in my text. Instead they seem to be numbered alphabetically. So the first reference in the whole document does not get number [1] unless I change the author name to something like "Aaa". But I want the first reference in the text to get number [1] (and the following references to be in the order which they appear) no matter what the author names are. I \usepackage{biblatex} and have all the references in \bibliography{references.bib} My questions:  Why aren't the references numbered in the order which they appear? What do you need to add (or remove?) to make the references be numbered in the order that they appear?

http://mirrors.ctan.org/macros/latex/contrib/IEEEtran/bibtex/IEEEfull.bib   defines a bibliography style.  How to use that if I want to use biblatex to format my bibliography?


Unlike the discrete case, the probability of any particular point in a continuous probability is zero. We must integrate over a small range of the pdf to bring a non-zero value.  In a machine learning model that assumes continuous data (as is oftend done for sound or images), the probability of any particular training data is zero.   Some models (such as variational inference models) are evaluated by their log likelihood.   My question: if the data is continuous, how can the likelihood be non-zero? The likelihood is assumed to factor over the data points, and the probability of each data point is zero, ...

I am trying to understand Maximum likelihood estimation but it looks like I am missing something rather elementary.          suppose we have an iid random sample $X_1, X_2,..., X_n$ for which the probability density function of each $X_i$ is $f(x_i; \theta)$ where $\theta$ is an unknown parameter. Then, the joint probability density function of $X_1, X_2,..., X_n$ is given by:          $f(X_1=x_1,X_2=x_2,\cdots,X_n=x_n)=\prod_{i=1}^{n} f(x_i, \theta)$      In Maximum Likelihood estimation, we try to maximize $f$ as a function of $\theta$.  Question: Why do we maximize probability density instead of probability? In what way does it make sense?  Edit: As explained in the answers, the probability of choosing a finite number of sample points from a continuous probability distribution is zero, so maximizing probability doesn't make sense, but how does maximizing probability density make sense?


I am trying to post images with cURL in PHP using multipart/form-data header.  I want to know what setting the "CURLOPT_POSTFIELDS" for curl.  I want to send like this value for server.  The element name has been used many times.  -----------------------------7e21b0029071a Content-Disposition: form-data; name="updates[]"  1 -----------------------------7e21b0029071a Content-Disposition: form-data; name="set_images[]"  1 -----------------------------7e21b0029071a Content-Disposition: form-data; name="updates[]"  1 -----------------------------7e21b0029071a Content-Disposition: form-data; name="set_images[]"  1 -----------------------------7e21b0029071a Content-Disposition: form-data; name="images[]"; filename="1.JPG" Content-Type: image/jpeg  ** raw image data ** -----------------------------7e21b0029071a Content-Disposition: form-data; name="images[]"; filename="2.JPG" Content-Type: image/jpeg  ** raw image data ** -----------------------------7e21b0029071a Content-Disposition: form-data; name="images[]"; filename="3.JPG" Content-Type: image/jpeg  ** raw image data * -----------------------------7e21b0029071a Content-Disposition: form-data; name="images[]"; filename="4.JPG" Content-Type: image/jpeg  ** raw image data ** -----------------------------7e21b0029071a--   I was teryed this option.  it was not work.  $data = array(     'updates[0]' => '1',     'set_images[0]' => '1',     'updates[1]' => '1',     'set_images[1]' => '1',     'updates[2]' => '1',     'set_images[2]' => '1',     'updates[3]' => '1',     'set_images[3]' => '1',     'images[0]' => new CURLFile('1.JPG'),     'images[1]' => new CURLFile('2.JPG'),     'images[2]' => new CURLFile('3.JPG'),     'images[3]' => new CURLFile('4.JPG'), );  curl_setopt($curl, CURLOPT_POSTFIELDS, $data);   Is it impossible to send the raw data of the first example?

I’ve run into a limitation in the cURL bindings for PHP. It appears there is no easy way to send the same multiple values for the same key for postfields. Most of the workarounds I have come across for this have involved creating the URL encoded post fields by hand tag=foo&tag=bar&tag=baz) instead of using the associative array version of CURLOPT_POSTFIELDS.  It seems like a pretty common thing to need to support so I feel like I must have missed something. Is this really the only way to handle multiple values for the same key?  While this workaround might be considered workable (if not really annoying), my main problem is that I need to be able to do multiple values for the same key and also support file upload. As far as I can tell, file upload more or less requires to use the associate arravy version of CURLOPT_POSTFIELDS. So I feel like I am stuck.  I have  about this problem in more detail on the cURL PHP mailing list in the hopes that someone there has some ideas about this.  Suggestions or hints on where I can look for more information on this are greatly appreciated!


I created a fighter which can jump very high, but I had difficulty determining how high I can exactly reach. I am a Goliath which is 8 feet tall (strength 20). Say my weapon has 5 feet reach.    Can I reach creatures which are 13 feet above the ground, while standing on the ground?

We encountered a Vampire Spawn in the 10-foot-high basement of an old church. The first strike was mine, after which the creature attacked my ally and retreated onto the ceiling as the thundering roar of my Booming Blade punished its retreat. Still inexperienced and unsure about my reach, after a short consultation with my mind, I decided to spend my turn switching to my trusty crossbow and make some distance.  However this turned out to be a mistake, since right after, the creature was in in my face trying to gouge out my eyes. Due to my nimbleness I managed to avoid its attacks. Regretting my earlier choice to change weapons I was left with the options to switch weapons and miss another turn, attack with disadvantage, or use my crossbow as an improvised melee weapon and trust in Booming Blade to hold the enemy in place after I disengaged.  Perhaps I should have switched weapons, but I decided that 1d4 (improvised weapon) + 1 (magic ring) + 1d8 (booming blade) was good enough. I missed.  On the plus side, it was my crossbow's sneak attack assisted bolt that finally slayed the Vampire by piercing its heart.    In this situation, would it have been possible to just attack upwards instead of changing to the crossbow?  In session, this was something to be looked up later and decided against, but I haven't found any rules on attacking in 3D.  With me being more than 5 feet in height and my melee attack range considered to be 5 feet, I should have been able to reach the ceiling itself, not to mention the Vampire Spawn hanging from it.    As for exact measurements (read this part only if you enjoy pointlessly over-analyzing things):  My character is 5 feet 6 inches/5.5 feet, which gives an  (for a human, my character is a Kenku), . This should give me a height of 8.3 to 8.9 feet from standing statically.    Testing it in real life, my estimated and standing reach match to less than 0.2 inches of the estimation on the site and I'm just shy of reaching my ceiling standing statically. As a test I tried moving as if I was attacking my ceiling and based on where I could feel my hand touch the ceiling, the length of my fingers and how much distance I lacked to reach my ceiling, I estimate about 0.4 feet in additional height. Considering that I'm taller than my character, let's say that gives 0.3 feet, increasing the height to 8.6 - 9.2 feet and that's still without changing how you hold the handle of the sword. In addition, just lying on the ground, my torso and legs measure about 0.6 feet.  Because my Kenku isn't a human, only a humanoid, it's impossible to estimate arm length which influences standing reach, however, considering that birds usually have a high wingspan and long legs, I think it's reasonable to assume that the arms should be as long, if not longer than, a human's.    So that would require the Vampire Spawn to be flat against the ceiling without any parts hanging down more than 0.2 to 0.8 feet for it to be outside of my reach. I consider that unlikely.  What are the actual rules for this type of scenario, or how do you handle it in your group? Should I be allowed to melee attack an enemy that's on a ceiling or low in the air?


Is it possible to check the BIOS version of my computer from a running Ubuntu instance?

How can get the BIOS version of my motherboard?  The command dmidecode gives you some information about the BIOS, but I can't find what I need...    I tried dmidecode command before asking and I didn't find what I needed - I want only the BIOS version and nothing else in the output.


I am trying to create a donut by following Blender Guru on youtube. The render was working fine but suddenly the icing of the donut is has become invisible.  While modelling:   After rendering:   Can somebody please help me find a solution? I am using blender 2.81a  file:

I have a project, and it has an object that has always rendered correctly, but one day when I open the project and make a test render, the object has disappeared. All the settings are normal, the object, and all of its children render display in the object outliner set to true. I really don't know what happened to it. Can someone tell me what I should look through to diagnose it? Sorry I cannot provide much detail. What I've explained is all I know. Edit: I am uploading the .blend file at  This is a Minecraft scene. It is the wolf that doesn't render. At one point it did, but now it just won't. The wolf has particle properties. I don't know if that matters, but it could. Look through all the wolf's properties to try and figure it out.


I am trying to do an analysis using matching on propensity score weights. In my data, treatement is a 3-class variable: no treatment, treatment 1, treatment 2. Outcome is a 2-class variable: 0 or 1 As the number of patients in the no treatment category is very high (8000) compared to treatment 1 (900) and treatment 2 (700), I would like to use 1 to many matching I used in R the twang package with the mnps command to generate propensity scores. I followed the twang tutorial but the analysis with svyglm seems to only use inverse probability weighting...is there a command that enables matching on the propensity score rather than IPTW? if matching is possible, how we do carry out the 1 to many matching? (I tried MatchIt in R but this only enables matching with treatment as a 2-class variable) thank you

What's the best way to use matching methods with multiple treatment groups? I'm assessing the impact of an intervention on an outcome. For my first analysis, I used the MatchIt package (see code below) to match treatment and control groups and to compare outcomes for the treated vs control. The Treat variable is 0 or 1.  nn_match <- matchit(treat ~ cov1 + cov2+ cov3 ,                      method = "nearest", data = df)   In my second analysis, I'd like to assess the effect of different treatment levels (for example, I have Treatment A, Treatment B, and Treatment C) on the outcome, but I'm stuck on the best way to proceed. Does it make sense to run separate matching analysis for each treatment group while excluding the observations from the other treatments groups?   nn_treatA_match <- matchit(treat_A ~ cov1 + cov2+ cov3 ,                      method = "nearest", data = df_minus_other_treatBC) nn_treatB_match <- matchit(treat_B ~ cov1 + cov2+ cov3 ,                      method = "nearest", data = df_minus_other_treatAC)   Or is there a way to run the analysis with the entire dataset and match controls to each treatment at the same time? Other posts have mentioned the twang package, but I'm not sure if that's what I should go with as I'd like to compare outcomes for each treated group to the control and not just across treated groups.


Consider the following sentences-  1- He is taller than me.  2- He is taller than i am.  Which one is grammatically correct and acceptable in various English language exams?  (I've read about it in some books.. Asked some teachers but still there is confusion)

Consider the sentence "I can run faster than 15 miles per hour." Its meaning is clear and to my eyes obviously grammatically correct. Now let me present some variations that have given me trouble for a long time.  I am faster than 15 miles per hour. – To me this is clearly incorrect. Directly comparing me to a speed doesn't seem right. We need to compare my speed to a speed, or me to another person.  I can run faster than him. – Compared to the base sentence, there is a distinct shift in meaning of the comparison. While before I named a speed faster than which I can run, now I am naming a person. It doesn't seem quite right. I realize the parts of speech can change, but my initial objection is that "him" is not a speed.  I can run faster than he. – This seems most correct to me, but still somehow feels objectionable. Is this in fact the correct way to say it? And if so, is it proper as is or need I say "... faster than he can" or even "... faster than he can run?"  I am faster than him. – With "am" instead of "can run" it now seems slightly more correct. But is it?  I am faster than he. – I'm in doubt here. It doesn't seem wrong to me to say, "I am faster than he is" or even "I am faster than he is fast." (Though I suppose that is a given since I could hardly properly compare to some other category as in "I am faster than he is smart.")  My speed is faster than his. – Hmm. This seems more proper as "my speed is greater than his."   So which of these constructions is correct and which is incorrect? Is there a general rule that I can follow? UPDATE The scholarly article  may be of great interest to some readers!  Once we accept that the elided constituent and its antecedent can differ in form, it becomes reasonable to ask how large this difference can be. The answer in Rooth (1992), Fiengo and May (1994), Chung et al. (1995) and subsequent work is that the wiggle room is actually quite small: the elided constituent and its antecedent are allowed to differ only in the realization of inﬂectional morphology. Other than that, both constituents have to be syntactically and lexically isomorphic.


I would like to fetch values:  Data1 Data2 Data3   They will always be included in the <element> tag  string sample = "This is a email template" +                 "which containe <element>Data1</element>" +                 "and also this one <element>Data2</element>" +                 "dont forget this <element>Data3</element>";  var match = Regex.Match(sample, "<element>(.*)</element>"); foreach (var item in match.Groups) {     var found = item; }   Loop executes twice with the following set of values:  1 => <element>Data1</element>and also this one <element>Data2</element>dont forget this <element>Data3</element> 2 => Data1</element>and also this one <element>Data2</element>dont forget this <element>Data3   Any idea, what I am missing here?

I have this gigantic ugly string: J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:\foo.pf J0000011: Job name: MBiek Direct Mail Test J0000020: Document 1 - Completed successfully  I'm trying to extract pieces from it using regex. In this case, I want to grab everything after Project Name up to the part where it says J0000011: (the 11 is going to be a different number every time). Here's the regex I've been playing with: Project name:\s+(.*)\s+J[0-9]{7}:  The problem is that it doesn't stop until it hits the J0000020: at the end. How do I make the regex stop at the first occurrence of J[0-9]{7}?


This is what comes up when I try to install Gnome via Terminal:  ansh@Ansh-HP-Notebook:~$ sudo apt update [sudo] password for ansh:  E: Could not get lock /var/lib/apt/lists/lock - open (11: Resource temporarily unavailable) E: Unable to lock directory /var/lib/apt/lists/ E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?  ansh@Ansh-HP-Notebook:~$ sudo apt install ubuntu-gnome-desktop  E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?

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


I am given a paper with Kaplan-Meier curve. I'd like "reverse-engineer" the chart to get the original data (without the censoring events, as they are difficult to discern in my low quality copy).  I've seen the tool for this task on the Net, but it was long time ago and  forgot its name.   Can someone please remind me, how to find it?  Thanks.

Anybody have any experience with software (preferably free, preferably open source) that will take an image of data plotted on cartesian coordinates (a standard, everyday plot) and extract the coordinates of the points plotted on the graph?  Essentially, this is a data-mining problem and a reverse data-visualization problem.


If $h:S^n\rightarrow S^n$ is null-homotopic prove that $h$ maps some point $x$ to its antipode $-x$.  I'm not sure how to proceed with this problem. I understand that null-homotopic means that $h$ is homotopic to a constant map $g:S^n\rightarrow S^n$. Unfortunately I haven't found a way to get a handle on the antipodal points. Any insights would help greatly.

There is a problem in Armstrong's Basic Topology in chapter 9.3 that I just can't seem to solve by myself, neither have I found a solution online. It goes as follows:      Suppose we have a map $f:S^n \to S^n$ that extends over $D^{n+1}$ in the sence that there is a map $F:D^{n+1}\to S^n$ with $F|_{S^n}=f$. Then there exists a $x\in S^n$ such that $f(x)=f(-x)$.    My idea was to glue two $D^{n+1}$ along $S^n$ to obtain the $S^{n+1}$ and a map $\tilde{F}:S^{n+1}\to S^n$ induced by $F$. Then by the Borsuk Ulam theorem I get a $x\in S^{n+1}$ s.t. $\tilde{F}(x)=\tilde{F}(-x)$, but I can't see how to get a $x\in S^n$ with this property.  Armstrong also states that $f$ having even degree is already sufficent, any hint on how to see that would also be much apprechiated.


Given this set: $$ S=\left\{\begin{bmatrix}a&-b\\b&a\end{bmatrix}\middle|\,a,b\in\Bbb R\right\} $$ Part I:  Why is this set equivalent to the set of all complex numbers a+bi (when both are under multiplication?) There is one matrix that corresponds to a specific complex number. Can this example be found and how can it be demonstrated to give equivalent answers?  Part II:  What is a formula for the multiplicative inverse of the matrix shown in the set, using knowledge on inverses of complex numbers?

I was reviewing some matrices and found this interesting  if $r = \begin{pmatrix} 0&1\\ -1&0 \end{pmatrix}$ then $rr=-I$, also $$\exp{(\theta r)} = \cos\theta I + \sin\theta r$$ No wonder, the matrix $R(\theta) = e^{\theta r}$ is the 2d rotation matrix, just like $e^{i\theta}$ rotates a vector in the Argand plane. I have a very cursory knowledge of complex analysis, so I would like to know where I can find the details, i.e what is the unifying theme and in which literature can it be found.


Related questions I have posted here so far:      Thanks to those who answered or commented on the questions above, I'm ready to order replacement resistors for R87, R88, R89, and R90 highlighted below:    The main objective of replacing the current resistors with ones with different values is to help the amplifier run as cool as possible because the originals seem to get hot enough to make the amplifier unstable. (I wouldn't mind some reduction in the output power, etc.) So, with this objective in mind, what would be the best and the second best choices as.45 the replacement resistors, among the following? (They all fit in the originals' locations, and they're all available for immediate shipping in the US today.)  Choice 1:  5W 1.5K ohm (same foot print, volume, surface area as the original's)  Choice 2:  5W 1K ohm (same foot print, volume, surface area as the original's)  Choice 3:  7W 1k ohm (same foot print, but volume and surface area bigger than the original's)  Choice 4:   7W 750 ohm (same foot print, but volume and surface area bigger than the original's)

I'm looking for four power resistors of the same type to replace R87, R88, R89, and R90 in the POWER AMP section of the amplifier of Klipsch SW-12 subwoofer shown below:    What should the minimum voltage rating of the following new resistors be?  Choice 1:  5W 1.5K ohm  Choice 2:  5W 1K ohm  Choice 3:  7W 1k ohm  Choice 4:  7W 750 ohm  Choices 1-3 all have their voltage rating listed (350V - 500V), but I can't find the voltage rating for Choice 4:    Datasheet:    If I can't find the voltage rating for Choice 4, should I drop it from my list of choices for the replacement resistors?  [A picture showing R88 and R90 with four other white resistors: Added 2/13/17]  There's a similar-looking row of six white resistors on the other side of the amp, too (bottom in the picture).    [Added 2/13/17]  I received a reply from a US distributor of the Choice 4 resistor:  Received: Mon, Feb 13, 2017 9:33 am Subject: MCPRM07WJP751B00  Hi  The max voltage rating is 500v.  I don’t have a data sheet to send but the product manager was able to contact the mfg to get the voltage.  Have a nice day.  . . . . . . . . . . .  [Added 2/14/17]  This is the resistor's listing that prompted me to ask a question about voltage rating for resistors:    I hadn't been able to find it until this morning.


It is known that in groups, rings, and fields, the inverse of any element under the operations of the structure, provided it exists, is unique.  Can one define a set of elements, along with an operation, such that the inverse is NOT unique?  What properties would such a structure have?

Let $M=\{x, y, z\}$ be a set and let $\circ$ be a binary operation on $M$ such that the identity element is $x$ and $y \circ y = x = y \circ z$. Prove that inverses need not be unique if associativity fails given the multiplication table below.  $x \circ x = x, x \circ y = y, x \circ z = z$  $y \circ x = y, y \circ y = x, y \circ z = x$  $z \circ x = z, z \circ y = x, z \circ z = x$


Do you think it would be worthwhile to provide hints as to what language to use for the syntax highlighting?  Sometimes I find the highlighting on SQL or VB.NET answers is more distracting than helpful; for example:       to pick the two I've been looking at recently.

I noticed that sometimes my code gets highlighted in different colors when rendered.   What is syntax highlighting? How does it work? Why isn't my code being highlighted correctly? How do I report a bug or request a new language? How do I use syntax highlighting? What languages are currently available on Stack Exchange?


When the load_upload() function gets executed, I want an explorer window to automatically open, so the user can select a file ($(imageFileInput).click();), and when a file is selected, I want the form to submit automatically.  The problem is that, when the form is generated dynamically as seen below, changes are somehow not detected. This seems to make it impossible to automatically submit the form when the value of imageFile changes.  How could I automatically submit the form this way? Any help is much appreciated!  function load_upload() {     var form = document.createElement('form');     form.method = "POST";     form.action = "image_upload_process.php";     form.id = 'imageForm';      var imageFileInput = document.createElement('input');     imageFileInput.type = "file";     imageFileInput.id = 'imageFile';     $(imageFileInput).click();     form.appendChild(imageFileInput);      document.body.appendChild(form); };   My change event:  jQuery(document).ready(function($) {     document.getElementById("imageFile").onchange = function() {         document.getElementById("imageForm").submit();     }; });

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


I am mounting my user filesystem in a server I connect to through SSH as a remote filesystem in my local Ubuntu machine.  For that I have been following the instructions in .  The first part, mounting the system, works fine (though I have to remove the defer_premissions option for it to work).  But I also tried the second part, editing /etc/fstab to mount the remote filesystem on boot, and it made my system boot up in emergency mode.  The problem got fixed immediatly as soon as I removed the sshfs#root@xxx.xxx.xxx.xxx:/ /mnt/droplet line from /etc/fstab, so it looks like that is indeed the culprit.  How do I fix this to mount the remote filesystem on boot?

From another SO , I understand I should create an entry in fstab to permanently mount an access to a virtual machine.  I am not Linux expert. The magic command which allows me to perform this from a terminal is:  sudo sshfs -o idmap=user -o allow_other -o nonempty jverstrynge@devjverstrynge:/home/httpd /home/jverstrynge/httpd   When I check the above SO question, I see an entry looking like this:  /media/mybook/laptop_backup /export/laptop_backup none bind 0 0   Can someone explain how to transform the CLI command into an entry in fstab?


For this task i have to capture not only month and year but also the entire string starting from i.e < a href using dummy sampler and regular expression extractor can u pls suggest me

Assign month as one varaible and year as one variable pass into next requst  For the above thing needed using bean shell post processor  and dummy sampler


I use the line of code below to loop through a table in my database:  $items_thread = $connection -> fetch_all($sql);   And if I print the array out:  print_r($items_thread);   I will get this:  Array (     [0] => Array         (             [RecipientID] => 3             [RecipientScreenname] => Tom L             [RecipientFirstname] => Thomas             [RecipientEmail] => info@xx.com         )      [1] => Array         (             [RecipientID] => 3             [RecipientScreenname] => Tom L             [RecipientFirstname] => Thomas             [RecipientEmail] => info@xx.com         )      [2] => Array         (             [RecipientID] => 1             [RecipientScreenname] => Lau T             [RecipientFirstname] => TK             [RecipientEmail] => lau@xx.co.uk         )  )   But I want to get rid of the duplicate items in the array, so I use array_unique  print_r(array_unique($items_thread));   I get the weird result below which is not quite I am looking for:   Array (     [0] => Array         (             [RecipientID] => 3             [RecipientScreenname] => Tom L             [RecipientFirstname] => Thomas             [RecipientEmail] => info@xx.com         )  )   Ideally, I think it should return this:  Array (     [0] => Array         (             [RecipientID] => 3             [RecipientScreenname] => Tom L             [RecipientFirstname] => Thomas             [RecipientEmail] => info@xx.com         )      [1] => Array         (             [RecipientID] => 1             [RecipientScreenname] => Lau T             [RecipientFirstname] => TK             [RecipientEmail] => lau@xx.co.uk         )  )   What shall I do to get it right? Have I used the wrong PHP syntax/default function?

How can I remove duplicate values from a multi-dimensional array in PHP?  Example array:  Array (     [0] => Array     (         [0] => abc         [1] => def     )      [1] => Array     (         [0] => ghi         [1] => jkl     )      [2] => Array     (         [0] => mno         [1] => pql     )      [3] => Array     (         [0] => abc         [1] => def     )      [4] => Array     (         [0] => ghi         [1] => jkl     )      [5] => Array     (         [0] => mno         [1] => pql     )  )


I am trying to replicate a caption like the one below.  Thus far I have made the following modifications:  \usepackage{caption} \captionsetup[table]{labelsep=newline, labelfont=bf, singlelinecheck=off, justification=justified}  \caption{Table title.\newline \indent Table subtitle.}   However \indent does not seem to work in caption, so how do I get a single line indented in my caption?  Thank you for your help.

Does someone know how to indent the text within captionof?  I have a long caption that I want to make two paragraphs out of but indent does not seem to work.  \documentclass{article}  \usepackage{caption} \usepackage[demo]{graphicx}  % make demo figure \makeatletter   \AtBeginDocument{%     \def\Ginclude@graphics#1{%       \begingroup\fboxsep=-\fboxrule       \fbox{\rule{\@ifundefined{Gin@@ewidth}{150pt}{\Gin@@ewidth}}{0pt}%         \rule{0pt}{\@ifundefined{Gin@@eheight}{100pt}{\Gin@@eheight}}}\endgroup}} \makeatother  \begin{document}  \noindent \begin{minipage}[c]{\linewidth} \centering \includegraphics{} \captionof{figure}{\textbf{Title} \newline \indent Paragraph 1 is found here with a lot of text lot of text lot of text lot of text lot of text lot of text \newline \indent Paragraph 2 is found here with a lot of text lot of text lot of text lot of text lot of text lot of text} \label{fig:angio} \end{minipage}  \end{document}


I have added a radio button to my content type and I have found that N/A was automatically put in as a selection.  How do I get rid of this?

I have a "gender" (checkbox) option that I want to show on the user profile page (but not on the registration page). The options are "Male" (default) and "Female". Since I don't make the field required it is showing the "N/A" option. Drupal does this .  If I make the field required the "N/A" option will go away but then it will automatically show on the registration page which I don't want.  I was trying to hide it with CSS but I cannot see a way to just hide that checkbox and "N/A" text:
 <input id="edit-field-gender-und-none" class="form-radio" type="radio" value="_none" name="field_gender[und]"> N/A

 <input id="edit-field-gender-und-0" class="form-radio" type="radio" checked="checked" value="0" name="field_gender[und]"> Male

 <input id="edit-field-gender-und-1" class="form-radio" type="radio" value="1" name="field_gender[und]"> Female
   Help! ;-)


32 bit Windows XP has two well-known memory limits. Each process is limited to 2GB of memory (or 3GB if you change a setting). The maximum memory that Windows XP will use in total is 3.25GB.  There is no fundamental 4GB limit for memory in 32 bit operating systems - Windows Server 2003 can use more than 4GB. The key limit that defines a 32-bit system is per-process (the virtual address space for one particular application). This is the reason for the 2GB/3GB per-process limit in Windows XP, which is also shared by Windows 2003 Server.  I dual-boot, with 64-bit OpenSUSE 11.3 Linux and Windows XP. Linux is becoming my main operating system more and more over time, but I have too many Windows XP apps that I use regularly to just discard them.  What I want to know, therefore, is whether there is any way to get memory above 3.25GB into practical use in 32 bit Windows XP. The kinds of possibilities I have in mind are...   A way of making Windows XP behave more like Windows 2003 Server. A way of replacing the hard disk cache handling in Windows XP with an alternative that can use extra memory. A RAM disk that can use non-Windows memory.   Two possibilities that may be worth a mention, but which I will reject for the moment, are...   Use Windows 2003 Server 32 bit - license issues. Use Reactos - still alpha, with significant issues, and I'm not sure if it can use more than 3.25GB memory anyway.   EDIT  In Joels answer, the final paragraph is...     If you have a lot of RAM (6Gb or more), I've also heard tales of people installing software that sets up a RAMDisk for the unused RAM and then placing the page file there.   If anyone knows where I can get suitable RAMDisk software, that is an answer I could accept. A normal RAMDisk isn't suitable because it will only use the memory that Windows manages, and therefore will more likely  and still leave the extra RAM unused.

I have Windows XP Pro 32bit, and cannot upgrade to a 64bit os for various reasons at the moment.  I read that I can use PAE to remove the 3.5Gb limit of a 32bit os by editing the boot.ini file.  Is this true, if it is true, how do I edit the my system so I enable the PAE?


Suppose we have simple circuit in which a battery of EMF $E$ is connected to a capacitor of capacitance $C$.  Work done by battery $W_{b}=CV\times V$ and energy stored in capacitor $=\frac{1}{2}CV^{2}$. Therefore the difference, which I'm assuming to be energy loss due to battery's internal resistance $=\frac{1}{2}CV^{2}$.  My question is why doesn't the energy loss by internal resistance depend on the chemical nature of the battery used? How do we define the quality of a battery if same energy is lost irrespective of their chemical composition in all of them ?  If my approach is wrong, what does this remaining $\frac{1}{2}CV^{2}$ signify?

A uncharged capacitor $C$ is connected to a battery with potential $V$. It becomes fully charged and has a charge $Q=CV$ stored on it.   Now the polarity of the battery is reversed. The capacitor will have the charge $Q$ still but with polarity reversed too.  My question is: What is the work done by the the battery?  According to me, during 1st charging it will do a work of $QV$. The energy of the capacitor is also not changing, then what is the work done to change its polarity?


I want to "annotate" a pdf with arrows and stuff drawn in tikz, but I don't understand how to put tikz draw commands inside the overpic put command.  Code:  \documentclass{standalone} \usepackage{tikx} \usepackage[percent]{overpic}  \begin{document} \begin{overpic}{filename_of_orig_pdf}  \put(0,0){Can easily put text}  \put(x,y){ \draw[] {}; }     %?  \end{overpic} \end{document}

Recently I have learned how to draw simple stuff with TikZ. I really like it. Now I wonder if it is possible to draw with TikZ on a image. Instead of pasting a image in Illustrator and adding some vectors to point something in the picture I would like to do it using TikZ. Is it possible?   For example, on a picture of a computer (PNG,etc) I would like to draw some arrows and labels saying "Keyboard", "Monitor", etc.


Let $D$ be an integral domain and $a,~b \in D$. Suppose that  $a^n=b^n$ and $a^m=b^m$ for any two some $m,~n$ such that $(m,n)=1$. Prove that  $a=b$.   I know that $ab≠0$ since $D$ contains no divisors of zero, but  I don’t have an idea as to how to prove this.

Let $D$ be an integral domain and let $a^m=b^m$ and $a^n=b^n$ where $m$ and $n$ are relatively prime integers, $a,b \in D$.   How do I show $a=b$?


I have to select and return 1 random character out of a string using this method (separate from main method):  public  static  char selectAChar(String s)  I'm not sure how to select the random variable, and not sure if i should use a for loop. everything I've tried I couldn't get it to return the right variable type.  EDIT: heres the coding i have so far  public static void main(String args[]) {     Scanner kbd = new Scanner (System.in);      System.out.println("Enter a string: ");     String s = kbd.next();      selectAChar(s); }    public  static  char selectAChar(String s) {   }   i tried something using this for loop for(int i = 0; i < s.length(); i++) but i can't figure out how to choose a random character and return it.

How do I generate a random int value in a specific range? I have tried the following, but those do not work: Attempt 1: randomNum = minimum + (int)(Math.random() * maximum);  Bug: randomNum can be bigger than maximum. Attempt 2: Random rn = new Random(); int n = maximum - minimum + 1; int i = rn.nextInt() % n; randomNum =  minimum + i;  Bug: randomNum can be smaller than minimum.


Is it true that $M=(M^{\perp})^{\perp}$ if $M$ is a closed subspace of a PRE hilbert space (a space with a scalar product, but that is not complete)?  The proof of the analog fact for hilbert spaces uses the projection on the subspaces $M^{\perp}$ and $(M^{\perp})^{\perp}$, but if the space is not complete that projection may not exist.

I am looking for an example such that in a pre-Hilbert space $H$ we have for a subspace $U$ that  (i) $\bar{U} \oplus U^\perp \neq H$  (ii) $ \bar{U} \neq U^{\perp \perp}$  Since finite and closed subspaces will probably not do it, I am not good at inventing nice examples. Does anybody here have a few at hand?


I am an Egyptian student and willing to visit Switzerland for less than 90 days. I hold a Portuguese residence permit (due to being a student, which I renew every year). I usually have no problems traveling to Schengen area countries. My question is, if I intend to visit Switzerland for less than 90 days, would I need any kind of authorization?

I have requested for a French long term (Type D) student visa from a consulate in India. It's a national Type D visa and not a Schengen visa. My question is that can we still go to other Schengen countries on this visa? If not then can we get a Schengen visa from a consulate in France?


So, the question that's always been bugging me is:   What is the proper usage of "This" and "That", not when it comes to objects or things, but when it comes to concepts.  For example, there's a paragraph that goes in a way that's similar to this:      "Coconuts kill a small number of people every year, yet wars have consumed many more lives than coconuts during the long period of human   existence.      That/This fact will not change anytime soon."   Another, simpler example,  is:      "Who is That/This friend you're supposed to meet?"   The basic difference between That/This is that "This" refers to a thing which is nearby, and "That" to a thing which is farther away.   So, how do you use the two words when it touches such vague examples? Does it even matter? Or maybe it would have been This when the statement is inside the same paragraph, and That when it's in another?

Learning and using English I'm always confused about what word to use for referring to things that have been described by me a few sentences earlier: "that" or "this".   Confusion comes from the fact that only the equivalent of "this" is always used in my native language for such referring. But I've noticed that in English for such referring "that" is used as often as "this" (or maybe even more often).  Some examples for illustrating (just tried to google something appropriate to convey my idea better):     We assess local... the demographics of the local population. What are the natural traffic drivers in the area. Things like cinemas and pubs and retail and office and all that type of things and we now put together a bit of a matrix and actually give a weighted score to each of the things we know help our business. That helps us decide in a more scientific fashion.   or:     The problem of Cervantes' origin became after that into a tough matter. Some experts believed that the Cervantes from Alcázar, in the times of the Lepanto Battle, was in the age of a child, more concerned about gathering nests and that type of things than about fighting as a soldier.   and for "this":     I believe lot of people who involved fishery industries in Mexico Gulf are suffering now but as for economic issues, U.S government and other countries will support them and give an utmost response to it. Important thing is that we learn from this mistake and make sure this type of things will never happen in the future and protect nature environment thus we have to take this technology to get energy from water very seriously. I really hope this technology will be available and used for everybody as soon as possible.   Is there a rule describing proper usage of these words in cases like this? (or should I have written "..in cases like that"?)


Let $R$ be a ring and $v: R \to \mathbb Z \cup \{+\infty\}$ a map that meets following axioms:   $v(a) = +\infty \iff a=0$ $v(ab) = v(a)+v(b)$ $v(a+b) \geq \min\{v(a),v(b)\}$   I have to show that $v(a) \neq v(b)$ implies $v(a+b) = \min\{v(a),v(b)\}$, but I have no idea where to begin, can anyone give me some hints?

Let $O$ be a discrete valuation ring with valuation $v$. We normalize by $v(\pi) =1$, with $\pi$ a prime element in $O$.  By definition, for all $x,y$ in $O$, we have $v(x+y) \geq \min (v(x),v(y))$. For some reason, the texts (Neukirch and Serre) suggest that one has equality when $v(x) \neq v(y)$. Where does this come from?  Does one also have an upper bound for $v(x+y)$?  I actually have elements $x_1,\ldots,x_n$ and I want to show that $v(x_1+\ldots+x_n) = \min(v(x_i))$. Does it suffice to show that $v(x_i) \neq v(x_j)$ for all $i\neq j$?


I know the meaning of $\int_{a}^{b}f(x)dx$, which is $F(b)-F(a)$. Geometrically, it gives us the area under the graph from $x=a$ to $x=b$ But what does $\int_{a}^{b}dx$ mean mathematically with respect to $f(b)-f(a)$ and what is its geometrical meaning?

I was considering the notation we use for integration, and was wondering what it means if we leave various parts out:   If its $\int_{a}^{b} dx$ it becomes $b-a$, as there is an "invisible" $1$, which we integrate. If its $\int_{a}^{b} f(x)$ what does that signify or represent? Can it be evaluated?   Thanks


I try to remove parts of the top bar in Ubuntu 18.04 with Gnome 3. First I have removed the whole top bar with a part of CSS because we didn't used it at all, but we have installed the TopIcons plugin for our notifications because our software work with that plugin. Removing the complete bar don't work anymore, because also the TopIcons are not visible then. I still like to remove the right top corner part of this bar, as we made our own "Shutdown and Restart" buttons in the menu. The reason is to avoid users using the settings panel and make it impossible to use the "wired settings".   I would like to remove this:    Is there any way to customize this bar or a way to remove parts of the top bar? I have used this CSS to remove the complete top bar, that was working well:  echo "#panel { height: 0px; margin-bottom: 20px; } #panel .popup-menu-arrow, #panel .system-status-icon { color: rgba(0,0,0,0); }" >> /usr/share/gnome-shell/theme/ubuntu.css

I have Ubuntu 18.04 and set the Scaling Factor in Tweaks to 1,10 because the 1920x1080 resolution makes stuff on my screen look a bit too small for my taste. That toggled this stickman icon, which now seems to not want to go away from my Panel unless I disable "Large Text".    Is there any way to hide this icon while keeping my settings?


I understand that Colour Temperature correlates with the object's thermal temperature, such as a red-hot piece of iron being ~360c and the incandescent bulb filament is about 2500c.   Why are sources of light, such as LEDs and florescent tubes, that emit white to white-blue light (which according to Colour Temperature, would be around 4500+c) cool, or nowhere near 4500c, when touched?  Also, why is the sky considered 10,000k? Especially if the surface of the sun is only ~5770k?

We know, via Wien's law, that a body at 6000K emits an electromagnetic wave at the peak wavelength in the visible spectrum.  How come say the fluorescent tubes which also emit the EM waves that we can see as visible not 6000K?


I have downloaded Ubuntu 14.04 from its official website. I've had problem installing it on my PC. Now I want to check whether my download was good or not as it took a long time to download .iso file. If the download isn't the problem, this would mean something else went wrong here and it would save me 6 hours of downloading this again.     I have  no technical knowledge, so is there any simple way that I can understand?  Now i have checked hash for the iso file and it doesnt matches, how can i repair it? any app is there to help me? as i have no knowledge for using codes or understanding them, what now? don't know what to do.  i have no linux os in my pc. so i can't use the terminal to download ubuntu. can i use terminal using livecd demo?  but using livecd demo slows my pc. how can i get a good download in windows?  any other suggestion ?

I've just downloaded a CD image of Ubuntu. I know the installer has a check CD option, but how can I check that the image is good before burning it to CD?


Is it legal in football that a player scores a goal in penalty by creating a pass (in forward direction as per rules) to another teammate and get passed back and repeat the passes until they want to score the goal? (any defensive moves from the opposite team are neglected)

I saw a video of Johann Cruyff , isn't that against the rules?


I've got this little doubt over the pronunciation of "tr" in words (trial, attraction,  actress). I recognized two ways of reading it - either as ch (like CHoose) + r or as t (as in Ten) + r, which I use interchangeably. Is one of these pronunciations correct, or are there rules as to which one to use in which situations?

Some of my students have a disagreement about transcribing the pronunciation of "trade" in American English. Some say it's (a) [t͡ʃeɪd] while others (and they point to dictionaries that support them) say it's (b) [treɪd]. I thought it was the former; the latter sounds a little like a fast "tirade". But now as I try to articulate it more, it seems like (c) [t͡ʃreɪd]. Any insights on this?


Hi guys and thanks to everyone will help me.  I have this query:  SELECT  c.accNum.bID.bID AS "Branch ID", --c.accNum.accNumber AS "Account Number", --c.accHolder.PrintFullName() AS "Customer Name", MAX(c.accNum.balance) AS "Balance" FROM tabCustomersAccounts c GROUP BY c.accNum.bID.bID--, c.accNum.accNumber, c.accHolder.PrintFullName(), c.accNum.balance ORDER BY c.accNum.bID.bID;     When I change the code to this:  SELECT  c.accNum.bID.bID AS "Branch ID", c.accNum.accNumber AS "Account Number", c.accHolder.PrintFullName() AS "Customer Name", MAX(c.accNum.balance) AS "Balance" FROM tabCustomersAccounts c GROUP BY c.accNum.bID.bID, c.accNum.accNumber, c.accHolder.PrintFullName(), c.accNum.balance ORDER BY c.accNum.bID.bID;     From this results you can see that I they are wrong because I want only the MAX balance to be displayed for each Branch.

Table:   UserId, Value, Date.   I want to get the UserId, Value for the max(Date) for each UserId. That is, the Value for each UserId that has the latest date. Is there a way to do this simply in SQL? (Preferably Oracle)  Update: Apologies for any ambiguity: I need to get ALL the UserIds. But for each UserId, only that row where that user has the latest date.


I am unable to use GRASS GIS algorithms like v.distance in QGIS. Earlier I used to use the same from QGIS before opening standalone GRASS GIS GUI. Is there anything I need to do to use GRASS algorithms in QGIS.

Running Windows 7 Professional (64bit) SP1. I have QGIS 2.18.10 installed from the standalone installer. The GRASS commands (161 algorithms) are present in the toolbox and seem to run ok. However the GRASS GIS 7 commands (314 algorithms) result in the following message box: I have tried uninstalling, deleting all traces of QGIS from the Registry, and then reinstalling using the OSGeo4W64 installer selecting various different options, including adding GRASS 6, also without any success. I deleted the OSGeo4W64 installation and reinstalled it. No change. I then re-installed the standalone QGIS package and copied the \msys folder from the OSGeo4W64 GRASS 6 installation into the \apps folder of the QGIS 2.18 directory. Nothing changed. I have ensured paths are correct in Providers section of Processing options:I have ensured the output folder has no non-ASCII characters as that seems to be another possible cause, but still have not solved the issue.


I would like to have two OSs without dual boot. Two drives, two OSs (Ubuntu + Windows 10), full separation of concerns.  The choice what to boot will be handled by Boot menu from the motherboard.  How to install them without any interference between them?  Helper questions:   Do I need to manipulate the boot flags or booting priority in UEFI/BIOS? Do I need to remove a drive to be safe in this process? To remove second m.2 drive I need to take out the motherboard. Should I do it in some order? Like 1. Windows 2. Ubuntu   I know a few ways of installing Ubuntu but I want to know which is easiest and safest. For now I did it the hard way by removing the drives.

How can I install Ubuntu on Windows 10 as dual boot? I have a DVD with Ubuntu and when I tried to install Ubuntu I had a warning that the hard disk will be erased. How can I install Ubuntu and keep my Windows 10? Thanks


I tried integrating it by part but it didn't work. I konw it can be solved by the  .Is there some elementary method for evaluate it or just some others? It seems there are at least (page 4 (17)) but I cannot think out any(the link only says there are four but not give any way).

How to solve the following integral.  $I(\theta) = \int_0^{\pi}\ln(1+\theta \cos x)dx$ where $|\theta|<1$


I'm new to Java and I just started learning about generics. I learned how to write a very simple GenericList: public class GenericList<T> {      private T[] items = (T[]) new Object[10];     private int count;      public void add(T item) {         items[count++] = item;     }      public T get(int index) {         return items[index];     } }  The line that particularly troubles me is the first field: private T[] items = (T[]) new Object[10];  I'm curious why this is allowed. I don't see how this is any different from something like this: private String[] items = (String[]) new Object[10];  The second statement satisfies the compiler because it sees we're trying to cast to a string, but breaks at runtime because downcasting doesn't work like that. The type "T" will of course always be a descendant of Object, so I don't understand how generics don't break at runtime for the same reason. I guess what I'm trying to ask is what exactly happens at: a) compile time, when GenericList.java is compiled b) runtime, when an instance of GenericList is instantiated Are instructions for creating a new Object[10] array compiled into GenericList.class? And then at runtime when an instance of that class is instantiated, that Object[] gets cast to whatever T[] is? Again, that's where I get confused because that should break the program. Any help/resource is appreciated! Thanks

I read about Java's type erasure .  When does type erasure occur? At compile time or runtime? When the class is loaded? When the class is instantiated?  A lot of sites (including the official tutorial mentioned above) say type erasure occurs at compile time. If the type information is completely removed at compile time, how does the JDK check type compatibility when a method using generics is invoked with no type information or wrong type information?  Consider the following example: Say class A has a method, empty(Box<? extends Number> b). We compile A.java and get the class file A.class.  public class A {     public static void empty(Box<? extends Number> b) {} }     public class Box<T> {}   Now we create another class B which invokes the method empty with a non-parameterized argument (raw type): empty(new Box()). If we compile B.java with A.class in the classpath, javac is smart enough to raise a warning. So A.class has some type information stored in it.  public class B {     public static void invoke() {         // java: unchecked method invocation:         //  method empty in class A is applied to given types         //  required: Box<? extends java.lang.Number>         //  found:    Box         // java: unchecked conversion         //  required: Box<? extends java.lang.Number>         //  found:    Box         A.empty(new Box());     } }   My guess would be that type erasure occurs when the class is loaded, but it is just a guess. So when does it happen?


I've some lat/long in EPSG:4326 coordinate system like Eiffel Tower position : ["lat" : 48.858274,"lon" : 2.2944]  For automated tests I would like to get, for every points of my dataset, the x and y coordinate of the location 100 meters Eastern of my dataset's point.  How can I calulate it?  PS : it'll be implemented in Java

Online calculators such as  (view page source) use the below formulas to get meters per degree. I understand in general how distance per degree varies depending on latitude location, but I do not understand how that translates to the below. More specifically, where do the constants, the 3 "cos" terms in each formula, and coefficients (2, 4, 6; 3, and 5) for "lat" come from?      // Set up "Constants"     m1 = 111132.92;     // latitude calculation term 1     m2 = -559.82;       // latitude calculation term 2     m3 = 1.175;         // latitude calculation term 3     m4 = -0.0023;       // latitude calculation term 4     p1 = 111412.84;     // longitude calculation term 1     p2 = -93.5;         // longitude calculation term 2     p3 = 0.118;         // longitude calculation term 3      // Calculate the length of a degree of latitude and longitude in meters     latlen = m1 + (m2 * Math.cos(2 * lat)) + (m3 * Math.cos(4 * lat)) +             (m4 * Math.cos(6 * lat));     longlen = (p1 * Math.cos(lat)) + (p2 * Math.cos(3 * lat)) +                 (p3 * Math.cos(5 * lat));


How do I fix this problem?? I have been getting it for days now and it is really annoying me! :'(

Any install that I'm trying through the Software Center is telling me:  Requires installation of untrusted packages: The action would require the installation of packages from not authenticated sources.  I did an apt-get update from the command line, then removed the software sources that the keys were bad from (PPAs I added myself), and unchecked them in the software sources for software center, but to no avail.  I can't install anything from software center anymore - only> from the command line with apt-get. Is uninstalling/installing the only option?  I don't want to break other PPAs that I have. Additional information: Here's a paste from apt-get update: Reading package lists... Done W: GPG error: http://ppa.launchpad.net oneiric Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B725097B3ACC3965 W: GPG error: http://us.archive.ubuntu.com oneiric Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key <ftpmaster@ubuntu.com>  I've tried apt-key update, and there was no effect (two keys unchanged). The output of apt-get update and apt-get upgrade, and the contents of /etc/apt/sources.list, can be found in .


I am looking for a word/phrase or saying for something that isn't so wonderful as people assume or say it is. Something that is lethal but people think it's a miracle.  I want to use it for a title of a book so it should be short.  All I could think of was Wolf in Sheep's Clothing...  Any suggestions are welcome.  Thanks

What are common phrases that describe something that appears good but is actually bad?  Edit: Because people say bad is vague I will try to sum up the phrase meaning a little better.   something that looks like it will be helpful or advantageous but after use it is hindering a tool that seems useful but is not the correct tool for the job something that seems like a good idea but after execution turns out to be problematic


I've found a few related questions in Java, but none for C#, so please forgive any duplicates.  Short and sweet, whats the difference? Is there any?  public static class Foo {     public static List<Bar> Bars;      static Foo()     {         Bars = new List<Bar>();     } }  public static class Foo {     public static List<Bar> Bars = new List<Bar>(); }   See the comment by @Nick G for the answer to the case of non-static classes. I'd still like to know if it affects static classes any differently.   Now they don't have to be static either. What about this case?  public class Foo {     public List<Bar> Bars;      public Foo()     {         Bars = new List<Bar>();     } }  public class Foo {     public List<Bar> Bars = new List<Bar>(); }

Is it better to initialize class member variables on declaration  private List<Thing> _things = new List<Thing>(); private int _arb = 99;   or in the default constructor?  private List<Thing> _things; private int _arb;  public TheClass() {   _things = new List<Thing>();   _arb = 99; }   Is it simply a matter of style or are there performance trade-offs, one way or the other?


How can a cryptographic hash function be implemented/created using the block cipher?  I was wondering if we can use AES in cipher block chaining mode to implement it.

This is theoretical question. I'd like to know if it's possible (and what are eventually the consequences), not that I'm going to do it in one of my projects. ;)  The first hashing functions created were based on a symmetric cipher (just like the first Unix crypt was based on DES). The idea was simple. Use the password as key to encode a constant.  I'd like to know if it's still possible to convert any modern symmetric cipher into a hashing function (and second question: into a cryptographic hashing function). Is it possible (easier) to guess the key, when you have an encoded and decoded messages?


I tried to fix the    :count($analyzed_sql_results['select_expr']   error in  :usr/share/phpmyadmin/libraries/sql.lib.php      but I cannot write to it. Error :      Error writing /usr/share/phpmyadmin/libraries/sql.lib.php: Permission denied

Using the Nano text editor, I'm trying to save and exit a file.  I already have the file named.  I click Ctrl+X to exit. And then I click Y because I want to save the file. It asks for file to write, I pressed Enter to use the default name because its already named.  The problem is I get this message.   [Error writing /filename: Permission denied]   What am I doing wrong?


I have Install Ubuntu 18.04.Battery is draining very quickly approx 1:30 hr only. while in window same laptop have upto 4:50 hr battery. I have Lenovo Ideapad 310 (i5 6th gen).

This question is present as a matter of historical interest.  While you are encouraged to help maintain its answers, please understand that "big list" questions are not generally allowed on Ask Ubuntu and will be closed per the .   It is possible to greatly extend the usage time of a laptop or netbook running on battery by disabling various services and installing various packages.   What tricks or tips do people have for getting an extra hour or two out of their batteries?


I am trying to predict the position (x,y)-coordinates of 16 peaks in an image. The images look like the following:      The green dots are the true peak locations and the red crosses represent a prediction of this network:      I have tried out many configurations of differnt Kernel sizes, number of layers, less/ more dense/ convolutional layers and so on.  I use Adam (lr=e-3) and a dropout of 20% here but I also have tried different configurations in this parameters. I train on a batch size of 64 and aim to regress the relative coordinates (also tried with absolute coordinates).  It seems that the network is not able to train the ability of recognising a peak; instead it regresses always a kind of average.  At the moment I lack of further ideas. So I hope someone can give me a hint of what I am doing so wrong.  Can you imagine of a reason for my problems?

I'm training a neural network but the training loss doesn't decrease. How can I fix this?  I'm not asking about overfitting or regularization. I'm asking about how to solve the problem where my network's performance doesn't improve on the training set.    This question is intentionally general so that other questions about how to train a neural network can be closed as a duplicate of this one, with the attitude that "if you give a man a fish you feed him for a day, but if you teach a man to fish, you can feed him for the rest of his life." See this Meta thread for a discussion:   If your neural network does not generalize well, see:


I would like to use Ubuntu on my Lenovo laptop with AMD APU Dual Core-E1-2100 and 4Gb RAM, let me know the compatible Ubuntu OS.

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


W:Failed to fetch http://ppa.launchpad.net/kirillshkrogalev/ffmpeg-next/ubuntu/dists/vivid/main/binary-amd64/Packages  404  Not Found W:Failed to fetch http://ppa.launchpad.net/kirillshkrogalev/ffmpeg-next/ubuntu/dists/vivid/main/binary-i386/Packages  404  Not Found E:Some index files failed to download. They have been ignored, or old ones used instead.   This is the error output. What's reason for this and what is a good solution?

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?


Can you help me to write the following symbol.  Thank you in advance.

I know what my symbol or character looks like, but I don't know what the command is or which math alphabet it came from. How do I go about finding this out?


I have intersected a cylinder with another. I have removed the faces the way I wanted and everything worked. Now I am trying to remove the layer of the 135 ° cylinder that intersects with the other cylinder. Below are the images:  and

I'm wondering how to approach duct work, piping, and wiring? In the past, I have used the spin tool to make corners, but I find it very cumbersome. How do you do duct work and piping? I have seen people use curves, but I find it's hard to get straight 90 degree angles or just uniform angling across the whole model. It's also hard connecting piping together if they started from different locations. Here's some reference:


I am doing a small course in SQL during my academic degree, I am very new with this material.    I saw  on StackOverflow, I tried to do INNER JOIN between my three tables, the INNER JOIN between the two tables are working well, but when I am adding the thired it's not working well, maybe I missed something?  this one is working:   SELECT Actors.FirstName,Actors.LastName  FROM Actors  INNER JOIN ActorsMovies  ON Actors.ActorID= ActorsMovies.ActorID;   this one doesn't work, I get an error message that something is missing:   SELECT Actors.FirstName,Actors.LastName  FROM Actors  INNER JOIN ActorsMovies  ON Actors.ActorID= ActorsMovies.ActorID  INNER JOIN GenresMovies ON ActorsMovies.MovieID=GenresMovies.MovieID;

I'm having problems joining three tables. It works well when I use the same query for joining two tables (after removing LEFT OUTER JOIN C ON B.No = C.No). However, it doesn't work when I use three tables.  This is my query  SELECT A.Name, B.Quantity, C.Quantity  FROM A  LEFT OUTER JOIN B      ON A.ID = B.ID  LEFT OUTER JOIN C      ON B.No = C.No;


I am new to UMVUE calculations and struggling a bit with this question. I want a hint about how to approach the derivation of the UMVUE for $\exp(t [\mu)$ for $N(\mu, \sigma^2)$ where (\mu is not known but \sigma^2 is known. I would go directly as finding the $E[h(T)] = e^{t\mu} $ I intend to use the density of $\bar X \sim (N, \sigma^2/n)$ in the computation of the expectation on the left side but I got stuck right after that. Thanks in advance.

Let $X_1, ..., X_n$ be iid. and $X_1\sim N(\mu,1)$. $\gamma(\mu)=e^{t\mu}$ for $t\neq 0$    My question is how to find an UMVU estimator for $\gamma(\mu)$  My concern is not so much about the specific problem but rather about how to approach this  kind of estimation problem in general, if one wants to estimate a non-linear transformation of a parameter. The problem for me is that $\overline{X}_n$ is UMVUE for $\mu$ but I think that: $E_\theta[e^{\overline{X}_n}]\neq e^{t\theta}$.   We never covered this kind of problem in our lecture so I dont really have an idea of how to solve this kind of estimation problem  EDIT: I think I solved it myself: Let $\frac{1}{k}:=\frac{1}{(2\pi)^{n/2}}$  $ \int e^{t\overline{X}_n} \cdot \frac{1}{k}\exp(-\frac{1}{2}\sum_{i=1}^n(x_i-\theta)^2)d(x_1, ..., x_n)= $  $=\int \frac{1}{k}\exp(-\frac{1}{2}\sum_{i=1}^n(x_i-2(\theta+\frac{t}{n})x_i+\theta^2)d(x_1, ..., x_n)= $  $=\exp(t\theta+\frac{t^2}{2n})\int \frac{1}{k}\exp(-\frac{1}{2}\sum_{i=1}^n(x_i-2(\theta+\frac{t}{n})x_i+(\theta+\frac{t}{n})^2)d(x_1, ..., x_n)=$  $=\exp(t\theta+\frac{t^2}{2n})$  The UMVU estimator is therefore $T(X1, ..., X_n)=\exp(-t^2/2n) \exp(t\overline{X}_n)$ It is UMVU because $\overline{X}_n $ is sufficient and thereby by Lehmann-Scheffe the estimator is UMVU, as $T(X_1, ... X_n)=g(\overline{X}_n)$  Remark: I would still have to proof that $Var_\theta(g(\overline{X}_n)) < \infty \forall \theta $ for Lehmann-Scheffe to be applicable.


I have a program in Windows 7 that launches ffmpeg in an external command prompt window but it is impossible to see what arguments were passed in.   Is there a way to see what arguments were given?

I'm looking for a tool or method to find out what command line parameters have been passed to a program, for example when it was run by another program (launcher-application scenario).


I have a class:  class InputMap {     public:         template<typename Function>         void setHotkey(sf::Keyboard::Key hotkey, Function onClick)         {             map[hotkey] = onClick;         }          void triggerHotkey(sf::Keyboard::Key hotkey)         {             if(map.find(hotkey) != map.end())                 map[hotkey]();         }      protected:         std::map <sf::Keyboard::Key, std::function<void()>> map; };   and when calling the setHotkey function like so:  setHotkey(sf::Keyboard::Left, [=](){TestActor->move(sf::Vector2f(-20, 0));}); setHotkey(sf::Keyboard::Right, [=](){TestActor->move(sf::Vector2f(20, 0));});   I get these errors:  ../Tyrant/include/Framework/InputMap.hpp|14|error: ‘void TGE::InputMap::setHotkey(sf::Keyboard::Key, Function) [with Function = TGE::State::setHotkey(sf::Keyboard::Key, Function) [with Function = TestState::enter()::__lambda2]::__lambda1]’, declared using local type ‘TGE::State::setHotkey(sf::Keyboard::Key, Function) [with Function = TestState::enter()::__lambda2]::__lambda1’, is used but never defined [-fpermissive]| ../Tyrant/include/Framework/InputMap.hpp|14|error: ‘void TGE::InputMap::setHotkey(sf::Keyboard::Key, Function) [with Function = TGE::State::setHotkey(sf::Keyboard::Key, Function) [with Function = TestState::enter()::__lambda3]::__lambda1]’, declared using local type ‘TGE::State::setHotkey(sf::Keyboard::Key, Function) [with Function = TestState::enter()::__lambda3]::__lambda1’, is used but never defined [-fpermissive]| ||=== Build finished: 2 errors, 1 warnings ===|   Now I'm guessing I could just compile with -fpermissive but I would like to avoid doing so.  EDIT:  Apparently the error was because the .cpp file for InputMap contained  template<typename Function> void setHotkey(sf::Keyboard::Key hotkey, Function onClick) {     map[hotkey] = onClick; }   and the header was   template<typename Function> void setHotkey(sf::Keyboard::Key hotkey, Function onClick);   So I guess it doesn't like the declaration and implementation to be in different files, possibly because of the template? Is there a proper way to do this or am I supposed to have it in the header only?

Quote from :     The only portable way of using templates at the moment is to implement them in header files by using inline functions.   Why is this?  (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)


Question Let $S = \{1, 2, 3, 4\}$. How many equivalence relation are there and describe them?  I know that 1~2 and 2~3. I also know that there are 2 equivalence relation but how do I prove that and describe them properly.

My question is:  How many different equivalence relations can we define on the set $A = \{x,y,z\}$?  I know that an equivalence relation is a relation that is symmetric, reflexive, and transitive, so how many I go about considering these possible relations?  I am particularly curious about this relation: $\{(x,x), (y,y), (z,z)\}$ Is it one possibility?


How to calculate the sum $S=\mathop{\sum}\limits_{i=0}^{\lfloor \frac{n}{4}\rfloor}\binom{n}{4i}$ ? Or how to get a good upper bound on $S$ in terms of $n$?

I am trying to obtain a closed form expression for  $\sum {n \choose 4k}$  I am trying to use the binomial expansion of $(1 + i)^n$ and $(1 - i)^n$. $$(1 + i)^n + (1 - i)^n = 2\left(\sum {n \choose 4k} -\sum {n \choose 4k + 2}\right)$$ Stuck at this now. I can't come up with a way to simplify the second term on RHS. Any help would be appreciated.


Debugger:  java.lang.NullPointerException: Attempt to invoke virtual method 'com.android.volley.Request com.android.volley.RequestQueue.add(com.android.volley.Request)' on a null object reference     at .MainActivity.addRemove(MainActivity.java:234)     at .ListItemAdapter$2.onClick(ListItemAdapter.java:66)   Where is the problem?  public void addRemove(Integer pos, List<ListItem> listItems) {     if (pos!=null){     boolean isSelected=listItems.get(pos).getIsSelected();     final String spotId=listItems.get(pos).getId();     if (isSelected==true){     URL_D=URL_DATA+"api-spot-favorites-add";     }     else{     URL_D=URL_DATA+"api-spot-favorites-remove";     }     StringRequest addRequest = new StringRequest(Request.Method.POST, URL_D,      ........          };          requestQueue.add(addRequest); }   Also the addRemove(pos, listItems) is called in  ListItemAdapter class and it's written in MainActivity class

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


Which is correct:        One fifth of the population is children.   One fifth of the population are children.

Should you use a plural verb if you refer to a fraction?     Nine tenths of the pillar have rotted away.   I think has should be used here, but I'm not sure.


Let $R$ be a commutative ring. We know that if $R^n\simeq R^m$ as $R$-modules for some positive integers $n,m$ then $n=m$. But is it still true when they are isomorphic as rings? Thanks!

I know from  that $R \times R$ can be isomorphic to $R$, as $R$-modules.     But can they ever be isomorphic as rings?


Let $I=[0,1]$. Find  $$\int_{I^n} \left(\min_{1\leq i\leq n} x_i \right)^a dx,$$  for $a\in \mathbb{R}$. Please help to solve this. Thank you.

Let $\alpha \in \mathbb R$ and let's call $I:=[0,1]$. Evaluate   $$  \int_{I^n} \left( \min_{1\le i \le n}x_i \right)^{\alpha}\,\, dx.  $$   Well, the case $n=1$ is easy and the integral equals $\frac{1}{\alpha+1}$, for every $\mathbb R \ni \alpha \ne - 1$.  I've done also the case $n=2$ and, if I'm not wrong, it's $\displaystyle \frac{2}{(\alpha+1)(\alpha+2)}$.  My big problem is that I cannot understand how to deal with the general case. Any ideas?   Thanks in advance.


My wife is from Kenya and meeting up with me in Spain for a vacation soon, using a Schengen visa. We will be touring in my car.   We also wish to visit friends in London briefly before catching the ferry to Dublin, Ireland.   Does my wife qualify for TWOV rules, (no U.K. Visa required), as we will be in the U.K. For less than 24 hrs?   Thank you.

Is there a website or some other way to find out if I need a transit visa for a short stop in the UK on my way somewhere else? Ideally this should give me the answer for all nationalities, and take into account any other visas I may have.


I am a South African with a Schengen Visa and visiting Poland as my country of entry. Can I then travel on to Romania. I can't clearly find out if Romania is Schengen or not.

I am Indonesian. This month I will go to Iasi, Romania for student exchange. But I will go there after staying one night in France, then take a plane to Iasi, Romania. Do I need to apply for a Romanian visa to enter and stay there for approximately 4 weeks if I already have a Schengen visa issued by France's embassy?


Let $f(z)$ be an entire function s.t. $|f(z)| < K|z|$, $\forall$ $z \in \mathbb{C}$, for some $K > 0$. If $f(1) = i$ what is the value of $f(i)$ and why? The value of $f(i)$ will be one of these four followings.   1 -1 i -i   My intuition is $i$ i.e. 3. I am imagining some boundedness property like Liouville's theorem, but I do not know accurate result(s) and proof(s). I am more interested in why part. Please add sufficient reference.   Thank you for your help.

Let $f (z) $ be an entire function such that $|f (z)|≤K|z|$, $∀z∈\mathbb{C}$, for some $K>0$. If $f (1) =i$, the value of $f (i) $ is (A)  $ 1 $ (B)$-1$ (C) $i$ (D) $-i$      how can I able to solve this problem?totally stuck.


On Ubuntu 18:04 Bionic (installed as a Singularity container) I issue   apt-get install okular   and I get the message "E: Unable to locate package okular".  Why? Is okular not in the apt repositories any more? How do I install it then?

When I try to install any package through the command line, I get an error.   $ sudo apt-get install <package> Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package <package>   Can anyone help me on this?


as part of a larger task I'm trying to print the length of an array in C, i.e how many elements are in an array. The array is an array of doubles, and I want to print a single integer which is how many doubles are in the array. I have this code:  int array_length( double array[] ) {     double length = 0;     length = sizeof(array) / sizeof(double);     printf("%G", length);     return 0; }   and I call it in main like this:  int main( void ) {     double test[] = {1.1,2.2,3.3,4.4,5.5};     array_length(test);     return 0; }   however this returns the error:     error: ‘sizeof’ on array function parameter ‘array’ will return size   of ‘double *’ [-Werror=sizeof-array-argument]   research has told me that   sizeof(array) / sizeof(double);   will give me the length of an array, and I am trying to using "%G" to allow me to print the double that this code returns.  I believe that "double*" means long double, so I tried changing "%G" to "%LG" and all uses of "double" to "long double", but that did not solve the problem. What is going on here?

First off, here is some code:  int main()  {     int days[] = {1,2,3,4,5};     int *ptr = days;     printf("%u\n", sizeof(days));     printf("%u\n", sizeof(ptr));      return 0; }   Is there a way to find out the size of the array that ptr is pointing to (instead of just giving its size, which is four bytes on a 32-bit system)?


I have the below code, and I want to center the col. elemnts so I used {||>{\centering}p{0.5\textwidth}||>{\centering}>p{0.3\textwidth}|}, but I got this error "\misplaced noalign" for the \hline command .. any idea how to fix the problem?. \begin{table}[h]         \label{1}         \begin{tabular}{|p{0.5\textwidth}|>p{0.3\textwidth}|}             \hline             \rowcolor{Gainsboro!60}             Student Name &Student ID \myhash \\             \hline             & \\             \hline         \end{tabular} \end{table}

The following code gives me an error:  \documentclass[12pt]{article} \usepackage[margin=2cm]{geometry} \usepackage [english]{babel} \usepackage{amsmath, amssymb} \usepackage{enumitem, array} \begin{document} {\begin{minipage}[t]{\textwidth} \begin{enumerate}[label=(\roman*)] {\setlength\itemindent{10pt}\item  \begin{equation*} \begin{array}{>{\centering\arraybackslash}m{1.5cm}>{\centering\arraybackslash}m{1.5cm}>{\centering\arraybackslash}m{1.5cm}>{\centering\arraybackslash}m{1.5cm}>{\centering\arraybackslash}m{1.5cm}}  \hline x & l_{[x]} & d_{[x]} & l_{x+1} & \mathring{e}_{[x]} \\ \hline \end{array} \end{equation*}} \end{enumerate} \end{minipage}} \end{document}   Note: for various reasons, I have to keep minipage there. For some reason, this code gives me an error when it compiles. It gives the following output:     The errors either say there is a } missing or a $ missing. My eyes don't see such a thing!


Disk util shows the encrypted disk I am using for time machine with the following info:  But the Menu entry "file -> Change Password" is greyed out. Tried to turn to the command line, I found this , and the first part works nicely: > diskutil cs list CoreStorage logical volume groups (1 found) | +-- Logical Volume Group DDE89BDF-9537-45FF-A786-697E828EB040     =========================================================     Name:         egmac2.bak     Status:       Online     Size:         2000021315584 B (2.0 TB)     Free Space:   9392128 B (9.4 MB)     |     +-< Physical Volume DFEAFE30-FF0B-417B-B845-7C0A283FB4D4     |   ----------------------------------------------------     |   Index:    0     |   Disk:     disk2s2     |   Status:   Online     |   Size:     2000021315584 B (2.0 TB)     |     +-> Logical Volume Family 0A741FD9-F957-4188-B1D9-233145A76ABF         ----------------------------------------------------------         Encryption Type:         AES-XTS         Encryption Status:       Unlocked         Conversion Status:       Complete         High Level Queries:      Fully Secure         |                        Passphrase Required         |                        Accepts New Users         |                        Has Visible Users         |                        Has Volume Key         |         +-> Logical Volume 253049D8-C1A5-41B1-A9C5-788AA41E0157             ---------------------------------------------------             Disk:                  disk3             Status:                Online             Size (Total):          1999659597824 B (2.0 TB)             Revertible:            No             LV Name:               egmac2.bak             Volume Name:           egmac2.bak             Content Hint:          Apple_HFS  But then: > diskutil cs passwd 253049D8-C1A5-41B1-A9C5-788AA41E0157 -oldpassphrase whatever -newpassphrase whattheheck diskutil: did not recognize coreStorage verb "passwd"; type "diskutil coreStorage" for a list

How may a Solid-state drive (SSD) Time Machine backup password be changed for a SSD formatted as "Mac OS Extended (Journaled, Encrypted)"? Expected This is how a Time Machine backup password is changed for an SSD formatted as "APFS (Case-sensitive, Encrypted)". APFS (Case-sensitive, Encrypted)  Open Disk Utility app > Select the drive under the External category. Select in the menu bar File > Change Password...   APFS Volume  Observed The Mac OS Extended (Journaled, Encrypted) formatted SSD has the option for Change Password... grayed out.  Mac OS Extended (Journaled, Encrypted)


During the opening, we hear Trinity and Cypher talking to each other.     Cypher: We're going to kill him, understand?   Trinity: Morpheus believes he is the One.   Cypher: Do you?   Cypher says this in a way which may indicate there have been deaths before.  If so, were these deaths on purpose or accidental? I'm thinking he means taking a risk with the agents.

In the beginning of the first movie, in the first conversation, between Cypher and Trinity, he says:     Cypher: We're going to kill him, understand?   Trinity: Morpheus believes he is the One.   Cypher: Do you?   Why did Cypher said that? Was it a habit to kill potential red pills? Was Neo considered to be a threat, so he needed to be killed if he was not the One?


It is established in The Terminator that anything travelling through time needs to be encased in living tissue. However, the T-1000 just seems to be made of liquid metal. Does the movie ever address this, or is it just a giant plot hole?

As we learn in the original Terminator movie only living, organic material can be sent back in time:     REESE: "You go naked. Something about the field generated by a living   organism. Nothing dead will go."      SILBERMAN: "Okay. Okay. But this... cyborg...if it's metal..."      REESE: "Surrounded by living tissue."      SILBERMAN: "Of course."   If this is the case then how was Skynet able to send the fully inorganic T-1000 and T-X model Terminators back in time?


Is there characterization of groups $G$ which can be written as the semi-direct of two other groups? One obvious necessary condition is that $G$ should have a normal subgroup. Is that the only condition? Thank you in advance...

I'm looking for examples of (families of) finite groups that are not semidirect products.   When first learning group theory, the first such group that one encounters is $Q_8$. In my search for other groups that are not semidirect products, the only examples I could find were simple groups, which clearly cannot be semidirect products since they don't have normal subgroups.   Does anyone have example of non-simple finite groups that are not semidirect products?


In most atomic nuclei there are both protons and neutrons.  Having a poor understanding of the strong interaction, it puzzles me why a nucleus must consist of both. Namely, why can there not be nucleus-like clusters of neutron, assuming both nucleons interact in similar ways in terms of strong interaction. This confusion is worsened by the fact that such a cluster would appear to be more stable than real nuclei, since there is no need to overcome the electrostatic repulsion between protons.  Hence the question: why do naturally occurring, stable nuclei necessarily contain both protons and neutrons? (with the exception of hydrogen nucleus)

"The answer lies in their one part in a thousand extra mass. Adding neutrons costs a little in mass, and in Einstein $E=mc^2$ implies that mass equates to energy. So it costs energy to add neutrons(due to their mass) and it costs energy to add protons(due to their electrical repulsion). This qualitatively explains why the elements have N larger than P, but not by too much. This extra energy locked into the neutron's mass also leads to instability. As nature seeks the state of lowest energy, like water running downhill to sea level, so a neutron left to itself will eventually experience beta decay: $n\to p+e+\nu$, which converts it to the marginally lighter proton, the excess energy being transformed into the electron and neutrino. So while a neutron in a nucleus can be stabilised, if you gather too many together, they will undergo beta decay, increasing the number of protons at the expense of neutrons. Conversely trying to put too many protons together and their net electrostatic repulsion destabilises them; in this case it is possible to lower the net energy by "inverse beta decay" where one of the protons converts to a neutron: $$ \rm p\text{ (in nucleus)} \to n \text{ (in nucleus)} + \text{positron} + \nu. $$ The net effect is when collections of N and P get too big a mismatch, beta decay or inverse beta decay moves the whole back toward the "valley of stability" where the number of neutrons N tends to exceed the number of protons P."  (The above is from a book called "Cosmic onion. Quarks and the nature of universe") From my understanding (not too sure as I am new on this), it took much more energy to gather protons together as compared to gathering neutrons together. What holds them together is the strong force and since the strong force holding them together is the same, there will be "a lot of strong force" left over when holding just neutrons together. As nature seeks to minimise the energy state of the nucleons, some of the neutrons will decay to proton such that there will not be "any strong force left over", hence ensuring that the energy state of the necleons are minimise. If what I say above is true, the neutron and proton "produce" equal amount of force carrier particles as is it because they themselves are made of quarks held together by the same colour charge and thus each of them produce the same amount of residual strong force?


We have developed a Predictive Model to show certain elements increasing and decreasing in certain locations of country.   What is acceptable in a prediction model accuracy?

I've fitted my model and am trying to understand whether it's any good. I've calculated the recommended metrics to assess it ($R^2$/ AUC / accuracy / prediction error / etc) but do not know how to interpret them. In short, how do I tell if my model is any good based on the metric? Is an $R^2$ of 0.6 (for example) sufficient to let me proceed to draw inferences or base scientific/business decisions?     This question is intentionally broad, to cover a wide variety of situations that members frequently encounter; such questions could be closed as duplicates of this one. Edits to broaden the scope beyond the metrics mentioned here are welcome, as are additional answers - particularly those that offer insight about other classes of metrics.


I am new to working with modular equations and am trying to find all the solutions to the equation $ 6x \equiv 9\pmod {15} $, here's what I have so far: $6x \equiv 9 \pmod{15}$ means $6x-9=15m$ for some $m\in \Bbb Z$. Therefore $$6x=15m+9$$ $$2x=5m+3,$$ which shows that $2 \mid (5m+3)$. Since $2 \mid (5m+3)$, we know that $2 \nmid 5m$ (otherwise $2$ would divide $3$, but $2 \nmid 3$). Therefore $2 \nmid m$ (otherwise $2$ would divide $5m$, but $2 \nmid 5m$). Therefore $m=2k+1$ for $k \in \Bbb Z$. Thus we have $$2x=5m+3$$ $$2x=5(2k+1)+3$$ $$2x=10k+5+3$$ $$2x=10k+8$$ and therefore, $$x=5k+4,$$ so that $x-4=5k$, and hence $x \equiv 4\pmod 5$. Therefore $x \in [4]$ (in modulo 5 arithmetic). I know that $ 5 \mid 15$ and that the congruence classes should be $x \in[4], x\in [9],$ and $x \in [14]$ (modulo 15). The problem is I'm not sure how to get back to mod 15 from mod 5/ what is the process of justification.

I know how to compute modular multiplicative inverses for co-prime variables $a$ and $b$, but is there an efficient method for computing variable $x$ where $x < b$ and $a$ and $b$ are not co-prime, given variables $a$, $b$ and $c$, as described by the equation below?   $ a x \equiv c \mod b $   For example, given  $ 154x \equiv 14 \mod 182 $, is there an efficient method for computing all the possibilities of $x$, without pure bruteforce?  Please note that I'm not necessarily asking for a direct solution, just a more optimized one.    I do not believe that the Extended Euclidean Algorithm will work here, because $a$ and $b$ are not co-prime.   Edit:  Follow up question, since the first one had a shortcut:  Could the be computed efficiently as well?  $12260x \equiv 24560 \mod 24755$.  $107$ needs to be one of the computed answers.


I am trying to declare a new command using the following string:  \newcommand{\to8}[1]{\xrightarrow{\mathmakebox[0.8cm]{#1}}}   but the compiler returns many errors.  I just don't understand why if I write  \xrightarrow{\mathmakebox[0.8cm]{iiiii}}   in the math mode the compiler returns no error but the compile does not allow it when I want to define it as a new command?

Possible Duplicate:          I wanted to know if it was possible to define a new command with a name that contains numbers?  e.g. \newcommand{\agent1}{agent~1}  Or even \ag1ent if having a number at the end is problematic.  I couldn't find the answer in the FAQ.


I have my screen at the lowest brightness level, the keyboard without light, and F.lux installed to remove the blue light from my screen. That has a very positive effect on my sleep schedule. Now, on my new Macbook Pro with the touchbar, there is this scandalous lighthouse below my screen. The brightness of that thing is giving me headaches. How can I just make it dimmer?

On the 2016 MacBook Pro, the touchbar has very high luminosity. At day it is very nice, but at night it blinds me.  It's especially vexing because I run f.lux's Darkroom mode to reduce the glare that might wake my wife up, and the main source of light is the Touchbar!  Is there any way to reduce the brightness, if not via a menu, maybe through a Plist somewhere or using the CLI?


I am trying to find the last 4 digits of $2^{2016}$. Here is where I am up to: 2^2016 = x mod 10000 2^2016 = x mod 625 - I used Eulers function to find that 2^16 = 1 mod 625 = 536 2^2016 = x mod 16 Now I am stuck. The second equation can not use Euler so how do I continue? Thanks

I've read about Fermat's little theorem and generally how congruence works. But I can't figure out how to work out these two:   $13^{100} \bmod 7$ $7^{100} \bmod 13$   I've also heard of this formula:  $$a \equiv b\pmod n \Rightarrow a^k \equiv b^k \pmod n $$  But I don't see how exactly to use that here, because from $13^1 \bmod 7$ I get 6, and $13^2 \bmod 7$ is 1. I'm unclear as to which one to raise to the kth power here (I'm assuming k = 100?)  Any hints or pointers in the right direction would be great.