Reading Files in C++
How do I read an entire file into a std::string in C++?
What is the name for moments, a parameter that is calculated Why does Quantum Field Theory use usually Lagrangians rather than Hamiltonains?  I heard many reasons, but I'm not sure which is true.   Some say it's just a matter of beauty, so Lagrangians are more beautiful because they don't break/separate the space-time variables (so space-time is a single variable, like in the Klein-Gordon Lagrangian and Hamiltonian).  Some say that Hamiltonians are not always Lorentz invariant.  Could someone explain in a little bit more details? I need this desperately but can't find it. Am I doing something wrong? Is it possible to open directories as administrator? I want to have a root privileges on some directories. How can I do this? In a multiple linear regression, why is it possible to have a highly significant F statistic (p&lt;.001) but have very high p-values on all the regressor's t tests?  In my model, there are 10 regressors. One has a p-value of 0.1 and the rest are above 0.9    For dealing with this problem see the . Fetch the row which has the Max value for a column 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. Find the maximum value of $ f(x) = \int^{x}_{0} \sqrt{(x^2-x)^2+y^4}~dy$ Find the maximum value of $f(x)$ when $0 \leq x \leq 1$ and $$ f(x) = \int^{x}_{0} \sqrt{(x^2-x)^2+y^4}~dy$$   I'm guessing that the Fundamental Theorem of Calculus can't be used because the integrand is a function of $x$.  Any help would be greatly appreciated. How do I remove a property from a JavaScript object? Please do not close this as a duplicate unless you can remove the “status-completed” tag from the  (because it’s obviously not been completed).  Steps to reproduce:   Have someone post an answer. Downvote the answer. Have the someone edit the answer within the initial 5 minutes of the answer’s existence. Try to undo the downvote more than 10 minutes later.   You cannot undo the downvote. The latex file coding is not there but the pdf file is there I wrote all my coding in the .tex file. The next day when I opened it the coding is all gone and the pdf file is opening with it and is displayed as an output. How do I bring back my coding? jquery stop child triggering parent event How to remove time from date? How to Select Columns in Editors (Atom,Notepad++, Kate, VIM, Sublime, Textpad,etc) and IDEs (NetBeans, IntelliJ IDEA, Eclipse, Visual Studio, etc) What is the weight equation through general relativity? I have been trying for a long time to change Blender's icon, but no matter what I do, I am not allowed to edit anything in /snap/blender-tpaw/3/.  Here's what I tried:   Editing the files from nautilus without sudo. Editing the files from nautilus with sudo (sudo nautilus in terminal ). Using terminal commands such as cp or rm without sudo. Using terminal commands with sudo (such as sudo cp &lt;source&gt; /snap/blender-tpaw/3/ or sudo rm /snap/blender-tpaw/3/&lt;filename.ext&gt;) Doing everything above in a root terminal (using sudo -i)   In every case I get the following error:  cannot remove/copy '/snap/blender-tpaw/3/filename.ext': Read-only file system   where filename is the file and .ext is its extension.  This also applies to other snaps' files, not only Blender.  Am I doing something wrong here? Or is it just impossible to change those files? Although I don't think it is impossible because everything here from Ubuntu to Blender is open-source, so they have no reason to block us from modifying those files.  EDIT:  I used Main Menu (alacarte) to change the icon, but I still want to know why I cannot modify any snap file. Sufficient and necessary conditions to get an infinite fiber $g^{-1}(w)$ Estimating partial sums $\sum_{n = 1}^m \frac{1}{\sqrt{n}}$ Apostol's Calculus, exercise number I 4.7 13.     Prove that if $n \geq 1$, then   $$ 2(\sqrt{n+1} - \sqrt{n}) &lt; \frac{1}{\sqrt{n}} &lt; 2(\sqrt{n} - \sqrt{n-1}) $$   and use this to prove that if $m \geq 2$, then   $$ 2 \sqrt{m} - 2 &lt; \sum_{n = 1}^m \frac{1}{\sqrt{n}} &lt; 2\sqrt{m} - 1 $$   In particular, when $m = 10^6$ the sum lies between $1998$ and $1999$.   After establishing the trivial case, for $n=1$, I can't think of a way to perform the inductive step:  assuming $2(\sqrt{n+1} - \sqrt{n}) &lt; \frac{1}{\sqrt{n}} &lt; 2(\sqrt{n} - \sqrt{n-1})$ and using this, deducing the same for $n+1$ is true as well:  $2(\sqrt{n+2} - \sqrt{n+1}) &lt; \frac{1}{\sqrt{n+1}} &lt; 2(\sqrt{n+1} - \sqrt{n})$  Any help is very appreciated, thanks How do I convert materials from Blender Internal to Cycles? I know this may be a tough or confusing question, but I have numerous existing materials I created and reuse for a project, which were all prepared for Blender Internal.  Now, I want to start the transition to Cycles, but I've hit a roadblock. How can I transition my materials without completely starting over? Or should I just forget it and start with fresh materials? I'm stuck in the College of Winterhold questline because of a glitch between the quests "Good Intentions" and "Revealing the Unseen." After talking to the Augur of Dunlain, I return to the Archmage Savos Aren to finish the quest, and he gives me the Mage's Circlet and finishes "Good Intentions." The problem is, the next quest "Revealing the Unseen" doesn't start. He talks about Mirabelle Irvine and tells me to go talk to her, but since the quest hasn't been started, she doesn't have anything to say about the Staff of Magnus. I've tried reloading from before the quest many times and finishing it but still the same result. I've also tried doing other quests and coming back to try and finish it later, but still the next quest doesn't start. I'm on the PS3.  Anyone have a way of fixing this bug/glitch? Thanks in advance. Integrating the inverse of a function. $f(x)$ is a strictly increasing, and continuous, function on $[0,+\infty)$. Consider the integral,  $$\int_0^a f^{-1}(x) dx.$$  Reasoning  The interval $[0,a]$ is "reflected" across the line $y=x$ onto the interval $0 \leq y \leq a.$  $f(x)$ and $f^{-1}(x)$ are symmetric across the line $y=x$. So, the integral is equivalent to the area bounded by $y = 0$, $y=a$, and $f(x)$.  So, "integrating $f$ along an interval on the $y$-axis" is the same as integrating $f^{-1}$ along the same interval on the $x$-axis?  Question  Is my reasoning correct?