While I was waiting in the Nottingham railway station I wanted to connect to the WiFi. However, I found 4 unsecured WiFi networks:   TheCloud _Notts City Free WiFi NET WiFi NCTX WiFi   I had no idea which one was official, and which might be fake ones provided by people intent on stealing my browsing habits.  Is there any way to determine the official WiFi? Would railway staff members know? Is there a list of WiFi networks in UK railway stations somewhere?  An answer that is applicable to railway stations in general would be great - I go through a lot and asking a question here for 8 different stations seems a bit silly.  Finally - I know public WiFi is deemed untrusted, so I use a VPN which I do trust and browse with Safari, rather than the official Apps, so that I can see the green padlock indicating HTTPS.
While traveling in the Berlin Tegel airport (TXL), I wanted to get on Wi-Fi. I found three unsecured networks in addition to a number of password-protected networks.   _Free_TXL_WiFi airberlin Berlin Tegel Airport WiFi   I had no idea which of these were an official Wi-Fi network provided by the airport and which were provided by other people, potentially for malicious purposes like capturing my network traffic. Presumably the official one uses a captive portal to allow internet access.  Is there any way to determine which Wi-Fi network is the official one provided by the airport? Would airport staff such as at the ticketing booths know? Are there official lists available somewhere?  I’d like an answer that is applicable to airports generally, rather than specific to the Berlin Airport. Also, please don’t just give a blanket “don’t use any public Wi-Fi network” answer; I know there are risks associated with it, but sometimes it is a necessity and so I want to know how to identify the airport-provided one.   suggests there are no official Wi-Fi networks, but the answers are six years old, so it’s not clear if things have changed or if none of the networks I saw were official.
Resizing or expanding a CoreStorage volume I bought a new SSD with 750 GB and made two partitions: 600 GB and 150 GB. The smaller one was thought to be a Bootcamp partition one day, but to date it was just another unused partition. When I needed more space, I decided to merge these two partitions. The partition was created with Mavericks, the merge was done with Yosemite.  I opened Disk Utility and the "minus" button. Disk Utility told me both partitions would be merged then. However it miserably failed. My main hard disc suddenly had errors which couldn't be repaired and even two of my other external hard discs could not be mounted any longer.  I eventually restored the hard disc from Time Machine, which worked well.  My second partition is now listed as free:    Unfortunately I can't resize the 600 GB partition nor can I create a new partition using the free space.  Diskutil reveils the following:  ~  diskutil list /dev/disk0    #:                       TYPE NAME                    SIZE       IDENTIFIER    0:      GUID_partition_scheme                        *750.2 GB   disk0    1:                        EFI EFI                     209.7 MB   disk0s1    2:          Apple_CoreStorage                         599.6 GB   disk0s2    3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3 /dev/disk1    #:                       TYPE NAME                    SIZE       IDENTIFIER    0:                  Apple_HFS Macintosh HD           *599.3 GB   disk1                                  Logical Volume on disk0s2                                  XXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX                                  Unencrypted   Also diskutil brought up this:  ~  diskutil cs list CoreStorage logical volume groups (1 found) | +-- Logical Volume Group 9D2BA4BA-xxxx-xxxx-xxxx-xxxxxxxxxxxx     =========================================================     Name:         Macintosh HD     Status:       Online     Size:         599640592384 B (599.6 GB)     Free Space:   6111232 B (6.1 MB)     |     +-&lt; Physical Volume 29A9A02B-xxxx-xxxx-xxxx-xxxxxxxxxxxx     |   ----------------------------------------------------     |   Index:    0     |   Disk:     disk0s2     |   Status:   Online     |   Size:     599640592384 B (599.6 GB)     |     +-&gt; Logical Volume Family 2FA7892F-xxxx-xxxx-xxxx-xxxxxxxxxxxx         ----------------------------------------------------------         Encryption Status:       Unlocked         Encryption Type:         None         Conversion Status:       NoConversion         Conversion Direction:    -none-         Has Encrypted Extents:   No         Fully Secure:            No         Passphrase Required:     No         |         +-&gt; Logical Volume 7BF42B7B-xxxx-xxxx-xxxx-xxxxxxxxxxxx             ---------------------------------------------------             Disk:                  disk1             Status:                Online             Size (Total):          599282155520 B (599.3 GB)             Conversion Progress:   -none-             Revertible:            No             LV Name:               Macintosh HD             Volume Name:           Macintosh HD             Content Hint:          Apple_HFS   I have tried this:    fsck -fy (The volume Macintosh HD appears to be OK.)   but it wouldn't help. It said I couldn't recover because it wasn't created in a way it would support (sorry for missing the exact message).  I then have learned that Apple_CoreStorage might indicate my disk is encrypted, which might explain why I can't resize it. It doesn't explain why I can't create a new partition to me.  What are my options to make my hard disk available in a single partition with size 750 GB? I would like to make cross references to own defined counter on environments. So far I have tried the following,   \documentclass{book} \newcounter{entryc}[subsection] \newcommand{\thetheorem}{\thesubsection.\arabic{entryc}} \newenvironment{qd}[1]{\refstepcounter{entryc}\noindent\textbf{Quasi Definition \thetheorem.}\begin{itshape}} {\end{itshape}} % \begin{document}  \chapter{First chapter} This is the first chapter.  \section{First section} This is the first section.  \subsection{First subsection} This is the first subsection.  \begin{qd}{}\label{qd:emp} This is my environment. \end{qd}  \noindent In quasi definition \ref{qd:emp} it \dots  \end{document}   What happens is that     But I would prefer "...In quasi definition 1.1.1.1". Do anyone have some suggestions of how solve this? and How to avoid the          \noindent  thing before the continuation of the text?   Additional information: if possible I would try to not use ntheorem. Suppose an entire function $f$ is real if and only if $z$ is real. Prove that $f$ has at most $1$ zero. Let $f$ be an entire function. Suppose $f(z)$ is real if and only if $z$ is real. Prove that $f$ has at most $1$ zero. How to prove? Totally I have no idea... Please give the solution in detail since I do not understand. Proper analyses for 2x2 contingency tables So I have multiple questions about the different types of analyses that can be used on a 2x2 contingency table and when different analyses should be used.   To open, I'll note that this stems from my efforts to find the appropriate analyses to run for research using categorical data in a 2x2 contingency table. In my case I have two conditions: control and experimental and within the experimental group there are two items of interest (say, Item A and Item B). In all cases I'm investigating whether an outcome occurs or not: How many experimental participants show the outcome on Item A? How many experimental participants show the outcome on Item B? How many control participants show the outcome? So in addition to comparing Item A with the Control group (A vs. C) and Item B with the Control group (B vs. C), I also want to compare Item A with Item B (A vs. B).   My understanding is that for between-subjects comparisons (e.g., A vs. C   &amp;   B vs. C) a  is traditionally used and that for within-subjects comparisons (e.g., A vs. B) that  is a common choice.   Question 1: is this an accurate understanding of the common choices for statistical tests using 2x2 contingency tables?    My follow-up questions, and where most of my confusion lies, are related to what to do when multiple observed cell counts are low (less than 10). I've explored numerous threads here, the Wikipedia pages for different topics (Yates's correction, Fisher's exact, etc.), a few journal articles, and descriptions in R-packages, but I have found conflicting views.   Some sources indicate that you should use , others say it's out-dated because, in addition to being overly conservative, it was only preferred because the other options were computationally intense.   Others say that you should use , but I've seen additional information suggesting that Fisher's exact test is only appropriate if you know both the row and column totals and that other options (Boschloo, Barnard, etc.) are generally more powerful. However, which of those to use is also not clear.  Finally, even others suggest that the Pearson's $\chi^{2}$ test is appropriate as long as the expected cell counts are not low.   I've seen some indication that these arguments occur for McNemar's test as well (e.g., continuity correction &amp; McNemar's exact test).  Question 2: Is the assumption regarding cell counts about expected cell counts or observed cell counts? If the observed cell counts are low, does that matter to the type of test that should be used?  Question 3: What is an exact test and when should exact tests be used?    In addition to answers to these questions, I would also greatly appreciate any suggestions as to books or articles I can read to learn more about this. Part of my struggle with all of this has been just general difficult finding clear information about these topics and how they relate to one another. At some point in (I think) the 90s, I saw an episode of something like Outer Limits or Twilight Zone where nobody was allowed to have more than average intelligence. Smarter children had to wear headsets which inhibited them from being too intelligent, administering minor electric shocks if intellectual thought was detected.  I can remember a final (or near final) scene of somebody watching his suicide and being upset but not remembering why because of the headset.  Can anybody identify the show and episode? Adjective for someone who exaggerates emotions to get sympathy What's the word for someone who tries to get sympathy from others by exaggerating their emotions or constantly reminding them of something tragic that happened to them?  I'm looking for an adjective - no disorders or health related definitions please. Calculate the sum of the infinite series $\sum_{n=0}^{\infty} \frac{n}{4^n}$ A previous problem had us solving $\sum_{n=0}^{\infty} \frac{1}{4^n}$ which I calculated to be $\frac{4}{3}$ using a bit of mathematical manipulation.   Wonderful. Thank you for all the prompt responses.  Could anyone suggest an alternate technique that does not involve differentiation? I've just downloaded a CD image of Ubuntu. I know the installer has a check CD option, but how can I check that the image is good before burning it to CD? How precise is the frequency of the AC electricity network? If I make a digital clock which first detects the AC frequency roughly (whether it is 50, 60, 100Hz, etc), then uses it as its clock pulse source, how precise would it be? Would it work world wide precisely?  For instance, in USA, what is the mean and standard deviation of the 60Hz AC frequency? Class not found loading JDBC org.postgresql.Driver In Python, how do I get a function name as a string, without calling the function?  def my_function():     pass  print get_function_name_as_string(my_function) # my_function is not in quotes   should output "my_function".  Is such function available in Python? If not, any ideas on how to implement get_function_name_as_string, in Python? Add notes under the table I'm using the latex package  because the  package isn't using APA style version 6 yet.  Now I'm trying to add a table with notes right underneath it, like in this table for instance:    Since the \caption{} is used as a title above the table, I have to add an extra row for the notes that goes over the whole table width. The problem is that the notes won't fit into one line so I need multi-line cell. How can I accomplish that? Or am I doing it totally wrong and there is a much easier way? I guess footnotes don't work here.  \documentclass{apa6e}  \begin{document} \shorttitle{} \begin{table} \caption{title} \begin{tabular}{cc} foo &amp; bar\\ \hline \multicolumn{2}{l}{Notes. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras lacus orci, porttitor et posuere sit amet, tempor non justo. Ut quis aliquet turpis. Ut dictum nulla eget purus elementum a lacinia libero varius. Donec malesuada nulla ut odio rhoncus convallis. Aenean faucibus sollicitudin sapien, a vestibulum ante rhoncus sit amet. In vitae mi justo. In arcu metus, porta et lacinia ut, ultricies sed eros.} \end{tabular}  \end{table} \end{document} How to solve "sudo: /etc/sudoers.d is world writable" Alpha over layers but maintain environment background Abnormal PREEMPTIVE_OS_AUTHENTICATIONOPS Waits Any difference between "Good morning, Brian" and "Good morning to you, Brian" I often hear it on TV when they are talking to a guest.  Normally, if we want to greet Brian in morning, we would say "Good Morning Brian". But many times TV presenters say "Good morning to you Brian".  Why is that? Why do they add "to you". There seems to be no need to do it.  Regards, One of the big new features for Windows is the fact that multiple "virtual" desktops are now natively supported, allowing you to organise collections of windows together and separate groups of tasks.  This is good.  You can move windows between desktops by clicking the "tasks" button and then right clicking an application window and selecting "Move to..."  This is a bit clunky and not quite so good.  I have two monitors and often like to have a film playing on my second monitor, either in a web browser or media player, while I have a browser and some other applications on the main screen. Doing this isn't a problem in my current setup, it just works.   With the advent of virtual desktops I was wanting to put the browser on one virtual desktop and another app on another virtual desktop and still be able to watch the video when I switch desktops, effectively having it visible on both virtual desktops. Using the default Film &amp; TV app to play a video and then moving to another desktop simply results in your video stopping without any warning.   This is not good.  What I was hoping was that either the two monitors would have their own virtual desktop or their would be some "pin to all desktops" option similar to the "sticky window" feature that I have seen in many Linux based window managers.  Is there some way to achieve this? Confusion on Derived Sets and the $n$-the Derived Set I want to solve the following exercise 1.3.C. from page 27 of R. Engelking: General Topology.  For every positive integer $n$ the $n$-th derived set $A^{(n)}$ of a subset $A$ of a topological space $X$ is defined inductively by the formulas: $$  A^{(1)} = A^d \quad \textrm{and} \quad A^{(n)} = (A^{(n-1)})^d. $$ (a) Give an example of a set of real numbers that has three consecutive derived sets distinct from each other.  (b) Give an example of a set of real numbers that has infinitely many derived sets distinct from each other.   The definition is $$   A^d := \{ x \in X \mid x \in \overline{A \setminus \{ x \}} \}. $$ I am confused, cause the set $A^d$ ist closed, i.e. $\overline{A^d} = A^d$. And closed means it already contains all its limit points, so how can than $(A^d)^d$ be different from $A^d$? How to find users by name Sum of principal minors