List of LaTeX ligatures Is there a comprehensive list of the LaTeX ligatures in basic font(s)?  Besides the long dashes formed by -- and ---, and some two and three letter combinations that start with f (like fi), I can't think of any.  I am not doing anything really fancy, just using RevTeX4 class to format my research papers.  I searched on the web but didn't find a comprehensive list, though perhaps I missed something.  Any help?
Which ligatures do the fonts used in my document offer? This is a follow-up question to:   In order to know which ligatures I might consider disabling (I have in mind microtype's \DisableLigatures command; some important notes about selective disabling of ligatures are found under ), knowledge about which ligatures might be applied will be very useful. Which ligatures do the fonts used in my document offer?
I would like to remove selected commit log entries from a linear commit tree, so that the entries do not show in the commit log.  My commit tree looks something like:  R--A--B--C--D--E--HEAD   I would like to remove the B and C entries so that they do not show in the commit log, but changes from A to D should be preserved. Maybe by introducing a single commit, so that B and C become BC and the tree looks like.  R--A--BC--D--E--HEAD   Or, ideally, after A comes D directly. D' representing changes from A to B, B to C and C to D.  R--A--D'--E--HEAD   Is this possible? if yes, how?  This is a fairly new project so has no branches as of now, hence no merges as well. What software is focused on reviewing and organizing images? Why is this trigger finding a null value despite the field being populated? Financial Account is a child of Client in a Master-Detail relationship. The client (John Sandbox) has a Wealth Advisor, 'John Smith', on his client record, however, the system debug that pulls finAcct.client__r.Wealth_Advisor__c shows this field as 'null'.  Does anyone have any idea why I am not getting the value in this field? The goal of this trigger is to make sure that the lookup fields for the Client Team (one of which is 'Wealth Advisor') always match between the client record and the financial account record when they are linked. Thanks!      Boolean UpdateMe;     List &lt;Financial_Account__c&gt; FinAcctsToUpdate = new List&lt;Financial_Account__c&gt;();      //Loop through all Financial Accounts in Trigger.new     for(Financial_Account__c finAcct : newFinAccts){         UpdateMe = false;          System.debug('finAcct WA Lookup: ' + finAcct.Wealth_Advisor_Lookup__c);         System.debug('Client: ' + finAcct.client__c);         System.debug('Acct WA: ' + finAcct.client__r.Wealth_Advisor__c);          if (finAcct.Wealth_Advisor_Lookup__c != finAcct.client__r.Wealth_Advisor__c){             finAcct.Wealth_Advisor_Lookup__c = finAcct.client__r.Wealth_Advisor__c;             UpdateMe = true;         }         if(UpdateMe == true){             FinAcctsToUpdate.add(finAcct);         }         UpdateMe = false;     }      if(FinAcctsToUpdate.size() &gt; 0 ){         update FinAcctsToUpdate;     } Random forest regression not predicting higher than training data I've noticed that when building random forest regression models, at least in R, the predicted value never exceeds the maximum value of the target variable seen in the training data. As an example, see the code below. I'm building a regression model to predict mpg based on the mtcars data. I build OLS and random forest models, and use them to predict mpg for a hypothetical car that should have very good fuel economy. The OLS predicts a high mpg, as expected, but random forest does not. I've noticed this in more complex models too. Why is this?   &gt; library(datasets) &gt; library(randomForest) &gt;  &gt; data(mtcars) &gt; max(mtcars$mpg) [1] 33.9 &gt;  &gt; set.seed(2) &gt; fit1 &lt;- lm(mpg~., data=mtcars) #OLS fit &gt; fit2 &lt;- randomForest(mpg~., data=mtcars) #random forest fit &gt;  &gt; #Hypothetical car that should have very high mpg &gt; hypCar &lt;- data.frame(cyl=4, disp=50, hp=40, drat=5.5, wt=1, qsec=24, vs=1, am=1, gear=4, carb=1) &gt;  &gt; predict(fit1, hypCar) #OLS predicts higher mpg than max(mtcars$mpg)       1  37.2441  &gt; predict(fit2, hypCar) #RF does not predict higher mpg than max(mtcars$mpg)        1  30.78899 Calculating square roots using the recurrence $x_{n+1} = \frac12 \left(x_n + \frac2{x_n}\right)$ Let $x_1 = 2$, and define $$x_{n+1} = \frac{1}{2} \left(x_n + \frac{2}{x_n}\right).$$ Show that $x_n^2$ is always greater than or equal to $2$, and then use this to prove that $x_n − x_{n+1} ≥ 0$. Conclude that $\lim x_n = \sqrt2$.   My question:  So I know how to do this problem but I don't know how to prove that $x_n &gt;0$ for all $n\in \mathbb{N}$. Ruby block and unparenthesized arguments I extracted simple example:  require 'pp' x = 1..3 pp x.map do |i| {:value =&gt; i, :double =&gt; (i*2)} end pp x.map { |i| {:value =&gt; i, :double =&gt; (i*2)} }  pp(x.map do |i| {:value =&gt; i, :double =&gt; (i*2)} end) pp(x.map { |i| {:value =&gt; i, :double =&gt; (i*2)} })   I am wondering why first pp produces:  [1, 2, 3]   While all the oders are giving:  [{:value=&gt;1, :double=&gt;2}, {:value=&gt;2, :double=&gt;4}, {:value=&gt;3, :double=&gt;6}]   I assume it has something to do with operator precedence. Where can I find good explanation? How to loop the particle simulation indefinitely? I've made a simple snowfall particle simulation (using gandalf3's solution: ). Is there a way to loop the animation, so the transition between last frame and first frame is not visible? Is there a setting to do it? Why didn't Voldemort murder the Dursleys? Voldemort couldn't kill Harry as long as he called the Dursleys home. Why didn't he just murder the Dursleys? This would prevent Harry from being able to live there. What to look for in a starter-level off-camera flash? I have zero experience with flash and want to learn how to use it from zero, for example by following the Strobist blog.  What are the absolutely necessary specifications I should look for when shopping for a flash, and can I find something in a price range less than $200.00?  My camera is a Nikon DSLR. I'm trying to educate myself on Granger Causality. I've read the posts on this site and several good articles online.  I also came across a very helpful tool, the , that allows you to enter your time series and calculate the Granger Stats.  Below, is the output from the sample data included on the site. I have also taken a crack at interpreting the results.   My Questions:     Is my interpretation directionally correct?   What key insights have I overlooked?   Also what is the meaning and interpretation of the CCF charts?  (I'm assuming CCF is cross correlation.)     Here are the results and plots that I have interpreted:  Summary of computational transaction Raw Input   view raw input (R code) Raw Output  view raw output of R engine Computing time  2 seconds R Server    'Herman Ole Andreas Wold' @ wold.wessa.net  Granger Causality Test: Y = f(X) Model   Res.DF  Diff. DF    F   p-value Complete model  356          Reduced model   357 -1  17.9144959720894    2.94360540545316e-05  Granger Causality Test: X = f(Y) Model   Res.DF  Diff. DF    F   p-value Complete model  356          Reduced model   357 -1  0.0929541667364279  0.760632773377753       My interpretation:    Test was based upon 357 data points and was performed with a lag value of 1 The p-value of 0.0000294 means I can reject the null hypothesis that x does not cause y for the Y = f(x). The p-value of .76 allows me to accept the null for X = f(Y) The fact that first hypothesis was rejected and second accepted is a good thing  I'm a little rusty on my F-test so I don't really have anything to say on this for now. I'm also not sure how to interpret the CCF graph.   I really appreciate it if any of you who are well versed with Granger-causality could let me know if I'm interpeting this correctly and also fill in some of the blanks.   Thanks for your help. Why are the dineutron and diproton unbound? It is known that there are no diproton or dineutron nuclei.  Does this mean that two protons or neutrons are not actually attracted to each other? Even if the attraction was weak, wouldn't it cause bound states anyway?  Related: Use of comma separating two adjectives If I had the phrase       two blond haired, blue eyed people    would the comma be out of place?    should I hyphenate "blond haired" and "blue eyed"? Show that $\sum_{n=1}^{\infty}(n^{3}\sin\left(\frac{1}{n}\right)-n^{2}+\frac{1}{6})$ converges Let $t\in \mathbb R$. Prove that $\displaystyle{\sum_{n=1}^{\infty}n^{3}\sin\left(\frac{1}{n}\right)-n^{2}+t}$ converges iff $t=\frac{1}{6}$.  While the $(\Rightarrow)$ direction was fairly easy (as $a_n$ should converge to $0$, forcing $t=\frac{1}{6}$), i'm facing some hard time trying to prove the second direction, that is $\displaystyle{\sum_{n=1}^{\infty}(n^{3}\sin\left(\frac{1}{n}\right)-n^{2}+\frac{1}{6})}$ converges. I did notice that $a_n=a_{-n}$ and tried to write this series as a Leibnitz series, but had no luck since the sequence doesn't decrease. I also tried to prove absolute convergence but then again, no luck. Thanks. Why use a ReentrantLock if one can use synchronized(this)? Can a wizard using an arcane focus quarterstaff and a shield still cast somatic component spells? If there is a wizard that, by some means, has acquired proficiency in the use of shields, can said wizard use his shield in one hand and his arcane focus quarterstaff in the other and still cast somatic component spells?  Since the quarterstaff has been crafted to also be an arcane focus, and the Sage Advice Compendium states that you can provide the somatic components of spells with the same hand wielding the arcane focus, in this case an arcane focus quarterstaff, could that wizard still be able to perform somatic component spells while using a shield in the other?  I understand War Caster is the feat that allows you to cast somatic component spells even while using a shield and weapon or two weapons in each hand, but is this a simple way around those rules seeing as this "weapon" is your arcane focus? I would like to believe it is not, but I'm not fully fluent in the ways of spellcasting. Winter Bash 2014 closing remarks - ideas for next year we had a question like this, and  SE  members have supported one this year, and nobody seems to have made one yet.  Hence:  What does everybody want for next year's Winter Bash? It's okay to repost old ideas that have already come up if you feel they haven't had enough attention (but please don't go just copy/pasting every  !).  A few ideas I can think of off the top of my head:   Moar hats! There's been plenty of time to get all the hats this year; it would be great if next year there'd be more to do. Keep secret hats secret-er. This could be pretty hard to do, but possibly by deleting/locking "how do I get secret hats" posts?   One idea per answer, please! I got a bash script to synchronize data between two computers. It works fine but I have to type my password every time the rsync command is called.   #!/bin/bash  sourceIP="192.168.178.128" sourceUser="user1" destinationUser="user2"  function sync() {      rsync --archive --progress -v -e "ssh -l $sourceUser " $sourceIP:/home/$sourceUser/$1/ /home/$destinationUser/$1 }  sync Pictures sync Music sync Videos sync Documents   How to store the password (via prompt) in a variable and pass it to rsync/ssh? In the 70's or 80's I read a short story in which 2 astronauts looking for a nice place to eat lunch choose a spot at the pole of a small desolate planet, overlooking the world's only pool of surface water.  Due to the harsh extremes of heat, and lack of water, this is the home of the planet's single living organism, which has grown slowly over eons,  surviving the daily extremes, moving slowly over the bare rock, dissolving it with acidic digestive juices to get the nutrients it needs for survival. The men watch the organism while eating their lunch, then depart, unknowingly leaving death behind them in their garbage - cigarette butts, tin cans, wrappings - a bonanza that the creature moves over to dissolve and ingest, along with the human-based microscopic organisms that will destroy the alien being. The theme of the story is that although we reach out to the stars to seek life, we are much more connected to the lowest forms of life on Earth, than to any life we may find on other planets. I don't remember the author and title.  Can someone identify the story? I'm on SO pretty much every day researching something to do with programming, and over the last month or two, I find I'm growing frustrated and a little disgusted at how many interesting questions have been closed as "not a good fit" or "too subjective".  I think there is a confusion between "subjective" and "calls for judgement". To me one of the most valuable things about SO is the tremendous breadth and depth of experience of the members, and experience translates into smart decisions and advice, and that advice cannot always be asked for, or expressed in terms of, bald facts and data.  It's going to be 'subjective'.  I don't think SO should be Wikipedia. I think that if I could ask a question to a group of skilled programmers sitting around a table at lunch, and get interesting, valuable answers, then I don't care whether the question or the answers are 'subjective', I think that question should equally well be fair game for Stack Overflow.  I would like to see a mechanism whereby people who vote to close a question lose reputation when somebody expresses interest in that question or its responses.  How can I, or can I, influence this aspect of SO? Is there a better alternative to ambiguous for a word with a wide range of meanings, difficult to find, because they become different in connection with person's opinion.