I have a lot of documents formatted like that:  \documentclass[a4paper,12pt,stdletter]{newlfm} \newlfmP{addrfromleft,addrtoright,dateright,orderdatefromto,sigright,noLines} \usepackage[utf8]{inputenc}  \namefrom{Hex} \addrfrom{Tex StackExchange} \dateset{\today} \addrto{Receiver}  \begin{document} \begin{newlfm} \textit{bla bla bla} \\[1cm] \begin{center}                             {\large Title} \end{center} Text \end{newlfm} \end{document}   They seem to compile correctly but i keep getting these errors:  ! Undefined control sequence. \@zfancyhead ...1\hbox to\headwidth {\fancy@reset                                                   \@zfancyvbox \headheight {... l.11 \begin{newlfm}   So the TeXstudio won't open the generated PDF although it is generated correctly. I am using MikTeX on Windows. What should i do to get rid of them? On the previous installation of TeXstudio+MikTeX, they didn't appear. I checked that i have newlfm installed in MikTeX Package Manager.
I updated to TeXLive 2017 and couldn't get newlfm.cls to work without errors.  Here is a minimal example:  \documentclass{newlfm} \begin{document} \begin{newlfm} \end{newlfm} \end{document}   LaTex is throwing undefined control sequence errors on \fancy@reset, \f@ncyolh, and \f@ncyorh.  What causes the errors?  What am I missing?
Newton's Law of Graviation: Why $G$ and not e.g. $\dfrac{1}{4\pi G_0}$? Is it acceptable to use "Just wondering" as a question? I often find myself writing sentences such as: "I am wondering if the landlord replied to you yet?"  And I always end up removing the question mark and rephrasing the sentence. In speech it is easy to inflect such a sentence so as to infer that it is a question, but in reality "I am wondering" is a statement and I feel it should not have a question mark when written down.  So is it acceptable to use "I am wondering" as a question? Renting a car in Ireland & Great Britain: 1 rental or 2? My wife, two kids and I will be traveling in Ireland and the UK Nov. 1st through 21st. We're flying into and out of Dublin. Our plan is to do a clockwise tour: Fly into Dublin -> Belfast -> Scotland -> England/London -> Back to Dublin to fly home.  We've been planning to rent a car when we land in Dublin (doing just things outside Dublin at the start of the trip) and have a car all the way until London, then turn in the car and take a train/ferry to get back to Dublin before flying home.  However, reading through the car rental section of Rick Steve's 2012 Ireland book is causing us to question if this is the right plan.  He says (p. 480):     If your trip covers both Ireland and Great Britain, you're better off   with two separate car rentals, rather than paying for your car to ride   the ferry between the two islands. On an all-Ireland trip, you can   drive your rental car from the Republic of Ireland into Northern   Ireland, but be aware of drop-off charges ($75-150) if you return it   in the North.   So it seems like he recommends against doing one car rental for both islands, but he also recommends against renting in the Republic of Ireland and returning it in Northern Ireland (our other option for our current itinerary).  So we're not sure which is best here.  A few questions about this:   If we do one car rental all the way from Dublin to London, will there be a similar $75-$150 fee? Is there an easy place to return a car on the Northern Ireland side of one of the Northern Ireland -> Scotland ferries, and an easy place on the Scotland side to rent a car?  We'd like to minimize the number of buses/whatever we need to take between car rentals since we'll be lugging around car seats for both of our children (on top of carrying them and our luggage). Will one way be significantly cheaper than the other?  Besides the basic cost of taking the car on the ferry and the drop-off charges, our credit card will cover insurance in Scotland/England but not in Ireland, so we could potentially get a better rental rate by renting a second vehicle once we're on Great Britain. Although, I know you often get a better rate when keeping a car rental for longer, so that may negate any benefit from the credit card covering the insurance. A correct preposition - account closed due/by/at 12th of May What's the shelf life on crushed specialty grains? I am working on a media project that contains little clips from movies and I wonder if there any way to avoid downloading all of the data instead only the specified parts of the movies? Many sysv init scripts used a corresponding file in /etc/default to allow the administrator to configure it. Upstart jobs can be modified using .override files. How do I override or configure systemd units, now that systemd is the default in Ubuntu? Rooks on a 8 by 8 checker board. Probability problem Two rooks are placed on an 8 by 8 chessboard such that they're in different squares. What is the probability they can't attack each other? Rooks can attack each other if and only if they're in the same row or column. I know that there are questions like this but they give the general numbers not the probability I am not sure how to start the questions and I have looked at this questions for hours. Any help would be welcome. Recently I began studying machine learning, however I failed to grasp the intuition behind .   The following are the facts about logistic regression that I understand.   As the basis for hypothesis we use . I do understand why it's a correct choice, however why it's the only choice I don't understand. Hypothesis represents the probability that the appropriate output is $1$, therefore the domain of our function should be $[0,1]$, this is the only property of sigmoid function I found useful and appropriate here, however many functions satisfy this property. In addition, sigmoid function has a derivative in this form $f(x)(1-f(x))$, but I don't see the utility of this special form in logistic regression.   Question: what so special about sigmoid function, and why we cannot use any other function with domain $[0,1]$? The cost function consists of two parameters ${\rm Cost}(h_{\theta}(x),y)=-\log(h_{\theta}(x))$ if $y=1, {\rm Cost}(h_{\theta}(x),y)=-\log(1-h_{\theta}(x))$ if $y=0$. In the same was as above, I do understand why it's correct, however why is it the only form? For example, why couldn't $|h_{\theta(x)}-y|$ be a good choice for the cost function?  Question: what is so special about the above form of cost function; why cannot we use another form?   I would appreciate if you could share your understanding of logistic regression. Black screen after installation of Ubuntu 18.04 I did a fresh complete install of Ubuntu 18.04 on my ASUS M32CD desktop.   Everything during install went fine. At the end it said it was complete complete, and would reboot. Popped the disc out. Rebooted itself back into bios so I changed it back from CD boot as primary to HD.  When it booted up for Ubuntu screen and then everything went black and can’t do anything now! Ugh. Help How to derive addition of velocities without the Lorentz transformation? Lorentz contraction and time dilatation can be deduced without Lorentz transformation. Can you deduce also the theorem of    $$w~=~\dfrac{u+v}{1+uv/c^2}$$   without Lorentz transformation? Using just the constancy of light speed. Give an example of a convergent series $$\sum_{n=1}^{\infty}a_n$$ such that the series $$\sum_{n=1}^{\infty}a_{3n}$$ is divergent..  I cannot find find any kind of series... I am also be very thankful if you find a divergent series (changing the term convergent)... How do I cherry pick packages from a PPA? "That... be" construction How to show that the spherical metric satisfies the triangle inequality? For $x,y\in \mathbb R^n$ define  $$d(x,y)={\|x-y\| \over \sqrt{1+\|x\|^2} \sqrt{1+\|y\|^2}}$$ Here $\|x\|$ is the euclidean norm of a vector. How to prove that $d$ (the spherical metric) is indeed a metric?     Progress so far:    $d(x,y)\ge 0$ is obvious. $d(x,y) =0 \iff \|x-y\|=0 \iff x=y$, so the positivity holds. $d(x,y) = d(y,x)$ is clear from the formula, so symmetry holds.    But I am having difficulties with the triangle inequality. Writing it out in coordinates leads to a complicated inequality with square roots all over the place in denominators. Is there a better way? We are doing research on monitor human activities to avoid adverse events. In part of it, we did an experiment in our MoCap lap to detect the human motion to monitor his activities. We have f-curves from that motion. But we need all the xyz coordinates values for that motion for that given time (just say about 2-3 minutes) to do a scientific analysis of the data.  Do anyone have an idea how to get xyz values from f-curves? Do Stack Exchange sites allow editing of comments and posts from other users? Why are duplicates not being merged? I see more and more exact duplicates on SO. Instead of being merged they are being simply closed. I think this is very big disservice to SO. Why don't moderators merge duplicates? Why don't owners of the site do anything about this?  EDIT  It's disservice because this way we have more and more junk. Duplicates are duplicates and should be merged so that information in in one place.     If the duplicate has no answers then there is no benefit to merging.   Of course there is. You don't need to waste your time with dupes.     It also means that the search routes to the main question are   diminished which makes the posting of new duplicates more likely   There's easy solution for this which I gave in  back in march.     If both questions have answers that have been accepted, which one   should be unaccpeted?   There are plenty of solutions. You accept most voted accepted answer or the first accepted answer or both (I think this is be the best). Yes, there will be possibility of many accepted answers to one question. So what?     When a question is closed as a duplicate, there is a link to the   duplicate question. What more do you want?   I don't want yet another link. I want to have all answers to some problem in one place. Is this that hard? Isn't this natural expectaion?     Removal of the question means that the text in it is no longer searchable - that's a disservice.   See my answer above to Scrooge's comment. Proof: in $\mathbb{R}$, $((0,1),|\cdot|)$ is not compact. Let $(M,d)$ be a metric space, and $A\subset M$. By definition, $A$ is said to be compact if every open cover of $A$ contains a finite subcover.  What is wrong with saying that, in $\mathbb{R}$, if $I=(0,1)$, we can choose $G=\{(0,\frac{3}{4}), (\frac{1}{4}, 1)\}$, which satisfies $I \subset \bigcup_{U\in G} U$, but we can't extract a finite subcover, so $I$ is not compact. Is $G$ a finite subcover of $G$, so it is not a valid cover for proving this? I would take $\cup_{n\in\mathbb{N}} (\frac{1}{n},1)$ in order to prove this, can we conclude that every open cover is necessarily a infinite union of open sets $\neq \emptyset$? Multiple "order by" in LINQ