How do I create a map view with an insert in QGIS?
Making overview with linked detailed maps in QGIS?
I'm preparing for my exam, but I have difficulties in perceiving why there is a $\frac{1}{2}$ in the distance formula $d=\frac{1}{2}at^2$? Mean or sum of gradients for weight updates in SGD I am using single observation to compute losses using neural network implementation in PyTorch. I am confused in a small detail of SGD. If I compute loss and do loss.backward(), I am accumulating gradients.  If I do this on 100 observations and then run optimizer.step(), should I average out the gradients?  This is what I am doing as of now:  def compute_loss(training_data):   for data in training_data:     loss = F.mse_loss(data[0], data[1])     loss.backward()  def optimize(sample):   optimizer.zero_grad()   compute_loss(sample)   optimizer.step()   Should it be rather:  def compute_loss(training_data):   for data in training_data:     loss = F.mse_loss(data[0], data[1])     loss.backward(torch.Tensor([1.0/len(training_data)])) Assign multiple colors to features within a single vector layer Nodejs Nginx error: (13: Permission denied) while connecting to upstream I'm trying to run multiple Nodejs applications on Nginx server running on CentOS 7. I noticed that when I run a Nodejs app on some ports I get an 502 Bad Gateway error in the browser so I checked the error logs:  [notice] 12806#0: signal process started [crit] 12807#0: *13 connect() to 127.0.0.1:7777 failed (13: Permission denied) while connecting to upstream, client: **.**.99.58, server: myapp.com, request: "GET / HTTP/1.1", upstream: "http://127.0.0.1:7777/", host: "myapp.com" [crit] 12807#0: *13 connect() to [::1]:7777 failed (13: Permission denied) while connecting to upstream, client: **.**.99.58, server: myapp.com, request: "GET / HTTP/1.1", upstream: "http://[::1]:7777/", host: "myapp.com"   when I change the app to listen to 8008 for example everything is working fine. I checked permissions and if the process is running as root and everything seems ok. I played with the timeouts as well but no result. Can anyone help? Find the volume common to two circular cylinders, each with radius r, if the axes of the cylinders intersect at right angles. (using disk/washer)  I saw no example of this problem anywhere.. I saw an example how to solve it without calculus but I'm afraid that'll be deductions on my test.. I have the volume of a cylinder and the method of area between two curves but this is out of my reach.... I don't know what I can try... $$(1+2+\cdots+n)^2=1^3+2^3+\cdots+n^3$$  I noticed this only because $\displaystyle \sum_{i=1}^n i = \frac{n(n+1)}{2}$ and $\displaystyle \sum_{i=1}^n i^3 = \frac{n^2(n+1)^2}{4}$.  But the two things look completely different and I can't think of an intuitive reason I would have seen this connection. Something like the 'Proof Without Words' images. Or a trick I could use while expanding the right hand side to transform it to the sum of cubes. Didn't Harry have any other family he could have searched for? How to prove this sequent using natural deduction? Simplify the expression $\binom{n}{0}+\binom{n+1}{1}+\binom{n+2}{2}+\cdots +\binom{n+k}{k}$ Chat flag notification, but no flag It appears  is back. Upon refreshing any chat page (even when dumping the cache and hard reloading), a chat flag notification is displayed, but there is no chat flag. This is a followup to my question  . StrongBad, in a comment replying to one of my comments, suggested that I go ahead and ask something along these lines. This question is directed at those who have experienced unwelcoming behavior. I'm so confused over the nature of the unwelcoming behavior that others have alluded to. If I can't figure out what is happening because it gets deleted quickly, there's little I can do to work toward preventing future occurrences. What, specifically, can individuals in the community do to support those who have experienced gender bias? I'm asking you -- those of you who have experienced bias related to being LGBTQ or some other sort of gender bias. What do you want or need us to do so that you feel welcomed?  Are you looking primarily for greater awareness of the issues you commonly face? That is, there is nothing really that specific for us to do except to attend sensitivity training, show greater empathy, etc. Do you want us to be more vigilant in voting down and flagging unwelcoming content so that it gets deleted quicker? Are there a few specific users that you want to be &quot;taught a lesson&quot;, and the rest of us are caught up in the crossfire? Do you want us to proactively ask you for your pronouns or other biographical or identity details before we engage with you? (I apologize for accidentally misgendering Aza in my previous question, but there's nothing on her profile to indicate her gender or that she wants people to be particularly sensitive in this regard towards her. Perhaps I could have sent her a note &quot;Hey Aza, I'm going to reference you in an upcoming post, what are your pronouns?&quot;, but that seems so awkward.) Do you want help with lobbying Stack Exchange into making changes to the existing system such as adding support for adding pronouns, sexual orientation, etc. to user profiles? How can I disable the Windows 8 charms bar? Can someone please tell me how to disable the annoying effect that pops up when you drag cursor to top- or bottom-right corners? Shortcut or button for copying posted code from Stack Overflow I might just be lazy, but do you ever find it tiresome to select all the source code from a large post on Stack&nbsp;Overflow to copy it?  I would like a feature, possibly a Firefox extension, but preferably a JavaScript script, for automatically copying source examples to the clipboard. It's no big deal for a small snippet, but a 1000+ line posting is cumbersome to copy.  Do you guys have a better way of copying large source posts? I'm using Firefox 3.5.5 on Windows&nbsp;7. How do I prevent widow/orphan lines? Can you restore log file backups to a mirror database after failure? Purely a theoretical question as I've been considering possible DR scenarios...  In this scenario:   The link between a principle and a mirror server becomes unavailable for a period of time (e.g. network outage) Incremental log backups are still being taken during this time Then the principle database fails and is unrecoverable   Is it possible to restore the incremental log backups onto the mirror to bring it up to date and back online, or would you need to start from scratch with a restore of a full backup?  Depending on the size of the database the difference could be hours of downtime so it would be nice to know.  I'm predominantly interested in SQL Server 2008 R2 and 2012 but other people may be interested in other versions if there's a difference. Writing a git post-receive hook to deal with a specific branch I occasionally update my kernel from this web site    I have been always downloading 3 deb files for installing  linux header all, linux image and linux headers. I noticed one more deb file recently for 64 bit kernel called Linux-image-extra.  I would like to know what does kernel file Linux-image-extra do and should I also install it? In my bash script I have an external (received from user) string, which I should use in sed pattern.  REPLACE="&lt;funny characters here&gt;" sed "s/KEYWORD/$REPLACE/g"   How can I escape the $REPLACE string so it would be safely accepted by sed as a literal replacement?  NOTE: The KEYWORD is a dumb substring with no matches etc. It is not supplied by user. I'm new to linux and the terminal. As I learn how to use the terminal to navigate through directories, I like to use the gui file explorer to mirror my terminal navigation. The icons and file extension info in the gui file explorer help me figure out what everything is. However, I can't access the root folder via the gui, I can only access it via the terminal. Is there a way to enable access to the root folder outside of the terminal? How to determine $\int x^2 e^{-x^2}\mathrm dx$?