How can i resolve the logical error in destruction of objects?
When to use virtual destructors?
Not able to install Win Xp on Lenovo Ideapad z570 I want to install Win Xp on my Ideapad Z 570 laptop but i always get blue screen with message with some drive related problem which asks me to run CHKDSK command. I tried with that but no luck. Is there any way i can install Win Xp with SP 2 ?  Edit: i searched across the sites and came to know there could be some Compatibility problems, and i could fix it by setting HDD mode to IDE; will it solve the problem? I'm running tests of a variable-size-and-contents test set. Data files are added and removed frequently. I'm looking for an automated way of gathering a file list.  All files are in subdirectories of D; I need the full directory and name added to a text file. However, I only need those files that have a "paired" file, which has the same filename but a different extension (so... different filename, but in a structured way). So, if there is a MyFileName.A and MyFileName.B, then I want D/.../MyFileName added to the file list.  There are .A files without .B files, but no .B files without .A files. If a .A has a .B file, then both files are in the same directory.   Any advice? Using special auto start servlet to initialize on startup and share application data What is the regular expression for a decimal with a precision of 2?  Valid examples:  123.12 2 56754 92929292929292.12 0.21 3.1   Invalid examples:  12.1232 2.23332 e666.76   The decimal point may be optional, and integers may also be included. From Rudin's Principles of Mathematical Analysis (Chapter 2, Exercise 6)  Let $E'$ be the set of all limit points of a set $E$. Prove that $E'$ is closed.  I think I got it but my argument is a bit hand wavy:  If $x$ is a limit point of $E'$, then every neighborhood of $x$ contains some $y\in E'$, and every neighborhood of $y$ contains some $z\in E$. Therefore every neighborhood of $x$ contains some $z\in E$, and so $x$ is a limit point of $E$. Then $x\in E'$, so $E'$ is closed.  The thing that's bugging me is the leap from one neighborhood to another. Is this formally correct? Simulate limited bandwidth from within Chrome? Trigger to check for duplicate contacts on lead conversion I'd like to write a Lead trigger, to check for duplicate Contacts before inserting the lead, or converting it.   Contacts fields I'd like to check:   Firstname - should not be the same as the leads name Lastname - should not be the same as the leads name Email - should not be the same as the leads phone   After checking these fields &amp; failing to find a duplicate, only then should the lead be converted. I've just happened to read this  on MO (that of course has been closed) and some of the answers to a similar  on MSE.   I know almost nothing of nonstandard analysis and was asking myself if something like the sentence « $1- 0.999 \dots$ is a nonzero positive infinitesimal» could be easily expressed and proved in nonstandard analysis.  First of all, what is 0.999... ? If we take the usual definition as a series or as a limit of a sequence of rationals, then it will still be a real number and equal to $1$ (I guess by "transfer principle", but please correct me if I'm wrong).  Instead, let's define  $$0.9_N:=\sum_{i=1}^N 9\cdot 10^{-i} $$  where $N\in{}^*\mathbb{N}\setminus\mathbb{N}$ is an infinite nonstandard natural number. This $0.9_N$ is a legitimate element of ${}^*\mathbb{R}$, expressed as $0.$ followed by an infinite number of "$9$" digits.  What can be said about $\epsilon_N:=1-0.9_N$ ? Is there an elementary proof that $\epsilon_N$ is a positive infinitesimal of ${}^*\mathbb{R}$ ? (by "elementary" I mean just order and field axioms and the intuitive facts about infinitesimals, like that for $x$ infinite $1/x$ is infinitesimal etc.; no nonprincipal ultrafilters &amp; C). \phantom causes a spacing issue between paragraghs Disappointed to see that the 18.04 installer no longer offers the option to encrypt the home directory. According to  bug report referenced in the installer, the recommended method for encryption these days is full-disk with LUKS, or fscrypt for directories. Full-disk encryption seems a bit overkill for my needs, and all the bugs and caveats mentioned on the  don't make it a very attractive option. All I really want is to protect my home directory from someone accessing my documents, photos, etc. if my laptop were to get stolen, making fscrypt the option for me.  The  has some examples on how to set it up, but I can't find any documentation aimed at encrypting the home directory on Ubuntu. The old ecryptfs tool is still available, but after setting it up Ubuntu would sometimes freeze at the login screen.  So my question is: How do I setup fscrypt to encrypt my /home directory and decrypt when I log in? I also liked how ecryptfs allowed decrypting the folder manually (eg. from disk images).  (A similar question was posted  and was unfortunately closed for being an "off-topic" bug report. To clarify, this is not a bug report. The fact that the encrypt home directory option was removed from the installer was intentional. All I'm asking here is how to setup fscrypt.) Recovering user files with a Live CD In Ex Machina, can this character survive? I was trying to prove following inequality:  $$|\sin n\theta| \leq n\sin \theta \ \text{for all n=1,2,3... and } \  0&lt;\theta&lt;π $$  I succeeded in proving this via induction but I didn't get "feel" over the proof. Are there other proof for this inequality? Using something like this:  try:    # Something... except Exception as excep:    logger = logging.getLogger("component")    logger.warning("something raised an exception: " + excep)    logger.info("something raised an exception: " + excep)   I would rather not have it on the error-level cause in my special case it is not an error. In the new canon what do we actually know about Darth Plagueis? I read and loved  but with all the recent changes to what is and isn't canon I'm losing track.  There's a common theory that Supreme Leader Snoke is Darth Plagueis, most are discounted because Plagueis is a Muun. But where does that information come from? What current canon information do we have about Plagueis that disproves this theory and what has been marked as Legends? How can I get exactly 5 logarithmic divisions of an interval? How do I get past the "do not enter" traffic sign that stops me from installing "Sierra" instead of "High Sierra"?  I booted into rescue mode and deleted the original "High Sierra" installation, but booting from the USB stick with the "Sierra" installer on it still gives me the "no". Anyone know of a custom GPS ROM for Samsung Galaxy 5? Possible Duplicate:          I recently bought a Samsung Galaxy 5 (model number GT-I5500) and I'm new to the android world.   I'm not satisfied with the performance of the GPS on my cell phone so I thought it would be interesting to use a custom ROM to see if it improves a bit.   Anyone knows of a ROM that was tested in this model? I understand that the architecture of Convolutional Neural Networks (CNN) and Feed forward (FNN) are quite different. And that CNNs use pooling and filters of shared weights over a patch of the image. I am not so clear on the core convolution operator (1):   If anyone could link me to an explanation, I have looked at the Colah blog and Nielsen's online book, and I understand what it is doing but don't understand the convolution operator.  Also, it looks quite similar to the the core FNN function is there and difference? (2).  (1) convolution operator is $a^1 = \sigma(b + w*a^0)$ which is equivalent to:  $a^1 = \sigma(b + \sum^4_{l=0}\sum^4_{l=0}w_{l,m}a_{j+l,k+m})$  (2) feed forward operation:  $a^1_i = \sigma(\sum^n_{j=1}w_{ij}x_j +b_i)$  Many thanks  Sources: functions taken from: Quantum computers are known to be able to crack  a broad range of cryptographic algorithms which were previously thought to be solvable only by resources increasing exponentially with the bit size of the key. An example for that is .  But, as far I know, not all problems fall into this category. On , we can read     Researchers have developed a computer algorithm that doesn’t solve problems but instead creates them for the purpose of evaluating quantum computers.   Can we still expect a new cryptographic algorithm which will be hard to crack using even a quantum computer? For clarity: the question refers to specifically to the design of new algorithms.