How to use a bash script variable with sed
sed substitution with Bash variables
Subscribing to questions and comments that don't belong to you There has been some discussion about getting notified on comments to questions or answers that don't belong to you, and the long-standing wish to be able to keep track of new answers or developments in questions asked by other people.  Previous discussion in regards to subscribing to questions:                  (very similar to this one)      In regards to subscribing to comments:                    The general feeling - at least here on meta - seems to be against broadening the notification rules, out of fears of useless notifications to flood users' inboxes, turning SO into more of a discussion forum than it should be, etc.   Here's a suggestion that would keep the user 100% in control what they get notified about, not generate any notifications by default, and require only minimal modifications to the User Interface.  Each question and each comment area would get an envelope symbol.    it is inactive (=white) by default.  When those envelopes are hovered over, the tooltip says click to subscribe or something.  When clicked on, the envelope lights up in green or some other colour (but different from the actual notification envelope's orange to avoid confusion.) You are then subscribed to any updates to that question or comment thread.    For each subscription, you receive notifications in the "responses" tab, as if you were the owner of the comment or question.     To unsubscribe from a question or comment thread, you open the page, and click the green envelope. It turns back white, and the notifications disappear from your responses tab (if technically possible - otherwise, there just won't be any new ones added.)    No further functionality, like managing subscriptions or anything, is necessary IMO. If the flood of notifications from a subscribed question starts to annoy you, you just open it and unclick the envelope. Done.   It would make it possible to leave a comment to a newbie's question and make sure their answer reaches you even if they don't know they need to address you using @username You could subscribe to those "oh, I'd like to know the answer to that" questions and receive active notification, instead of them getting forgotten in your favourites list You could subscribe to discussions you are interested in the outcome of, but don't want to participate in. It would (in my opinion) sort out a number of woes aired by many users in a good way, without adding annoyances to those who like the system just fine the way it is. It would not require a change in the visible layout. As far as I can see, the space the envelope would need to be is empty everywhere.   I don't know SO under the hood of course, but technically, the system would be doing what it's doing already, notify question owners of updates - just that the circle of internal "owners" would grow. In my recent study of Artinian modules I have been looking at Prüfer $p$-groups (which I will denote by $\mathbb Z_{p^\infty}$ from now on).   I am attempting to prove that $\mathbb Z_{p^\infty}$ is an Artinian $\mathbb{Z}$-module which is not finitely generated.      To do this I am trying to show that every proper non-trivial submodule of $\mathbb Z_{p^\infty}$ is equal to $\left(\frac{1}{p^n}\mathbb{Z_{}}\right)/\mathbb{Z}$ for some $n$.   I am using the following definition of $\mathbb Z_{p^\infty}$: $$\mathbb Z_{p^\infty}=\left\{x\in \mathbb{Q}/\mathbb{Z}\mid \exists n:p^nx=0 \right\}$$ I have read in several places, Atiyah &amp; MacDonald Example 6.3 and Wikipedia to name a few, that the subgroups of $\mathbb Z_{p^\infty}$ are of this form. This would demonstrate that $\mathbb Z_{p^\infty}$ is Artinian. However, I can't seem to find anywhere a proof or example showing why all the subgroups are of this form. I would like to understand this further, as it is not immediate to me that this would be the case, but my attempts to figure out why have so far been futile. I may be thinking too much and missing a simple explanation. I have looked at starting with an arbitrary subgroup $H$ such that $H\neq 0$ and $H\neq\mathbb Z_{p^\infty}$ and seeing if I can deduce anything from that. I got this far, but it doesn't seem to be going anywhere. I have also looked at Sylow's theorems, but I'm not sure if they will be any use to me as $|\mathbb Z_{p^\infty}|=\infty$ (unless I'm wrong about this!).  I would be extremely grateful if anybody could offer a few hints here as I am slowly losing my sanity trying to figure it out!  Thanks,  Andy. Making adult decisions are/is really not fun.     What is the proper answer and why? My gut says "is" but I can't explain why. Not that it's a very good idea to change it, but for fun. According to  post, there are still some problems even after changing entries in /etc/passwd, /etc/shadow, and /etc/sudoers. Any suggestions? Why are two universal objects isomorphic? Browsing some , it is claimed that two universal objects are isomorphic because they admit the identity morphism on themselves. But from two identity morphisms, how would you get an isomorphism between the two? "Coming soon" pages & SEO I am setting up my personal website, and I have designed a simple "Coming Soon / Under Construction" page which basically has nothing but a small notice for the users.   What kind of SEO can I make on this page such that it won't harm the full website's ranking later on? So just now, I had a bug in my site that caused my custom navigation bar's buttons to be sized and spaced incorrectly. I had no idea where this bug came from, and had to search around for awhile to find the answer. It turns out that SharePoint decided it would be a good idea to inexplicably add a few lines of:  nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;  nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;   between my   in my DevHome.aspx (I'm using Angular for this particular project). So, why does Sharepoint do this, and how do I prevent it? This is not the first time SharePoint has randomly added an nbsp to my page.  Thanks in advance. Comaximal ideals in a commutative ring Let $R$ be a commutative ring and $I_1, \dots, I_n$ pairwise comaximal ideals in $R$, i.e., $I_i + I_j = R$ for $i \neq j$. Why are the ideals $I_1^{n_1}, ... , I_r^{n_r}$ (for any $n_1,...,n_r \in\mathbb N$) also comaximal? What can I do when getting “This question body does not meet our quality standards”? Use /testfor to make a custom command Basically, I'm trying to recreate the Faction plugins /f map in my single-player without mods as my PC doesn't run them very well. (I know it sounds strange.) I am trying to use the /testfor to test if I have written '/f map' in chat, and if I have, it would show me a custom generated map. I don't know how to word this better xD Essentially what I want is for it to test if I have written a command in chat, and if I have, display something. Let $S=\{\{x\}\mid x \in \mathbb{R}\}$. Is $\sigma(S)$ included in the Borel $\sigma$-algebra on $\mathbb{R}$? Is $\sigma(S)$ equivalent to the Borel $\sigma$-algbrea on $\mathbb{R}$?    I think the answer to the first question is yes. Because the Borel sets include singletons, the Borel $\sigma$-algebra must contain the smallest sigma-algebra of the set of all singletons.   Here's my attempt at the second question: my answer would be no. Countable unions (or intersections) of countable sets are countable, so that any $X \in \sigma(S)$ is either countable or a compliment of a countable set. Therefore, the interval $(0,1) \not \in \sigma (S)$ but it is included in the Borel $\sigma$-algebra. My issue here is that I don't know how to formalize this statement, if it is even correct. How can I permanently enable cheating? Looking for title of a fantasy fiction with huge war, invader on airship with warlock, island fortress with sorcerer, mnemonic storyteller and dragon This was a thick book that I read over fifteen years ago that I never finished reading because someone borrowed it and didn't return it to the school library. I want to find its title.  The story takes place in a kingdom that is preparing for the a cycle of war, where every time the winds changes (50 or 100 years), invaders will try to cross the sea from another continent using airships with air balloons, filled with soldiers and warlocks. The kingdom has made several man-made island fortress along their coastline, filled with soldiers with war machines, sorcerers, and enchanters who act as the main guard/defence for the kingdom, calling lightning and fireballs, and using machines to stop and destroy and bring down as many of the invader airships as possible while countering the warlocks on board.  The book involved a man and a girl whose journey brought them apart in preparing for the imminent war.   The women found herself adept in magic and went to the academy in the capital to learn to be a sorceress.   The man found a different calling. With a good memory, he was sent to learn to become a mnemonic storyteller (to train with battle staff and fighting skill and mnēmonikos skill) who carried the history, literature of the entire culture in their heads. They used their knowledge to convey the kingdom's literature, poetry, history and stories to the people from generation to generation.  Both eventually "graduate". Sadly, and with great emotion, both have to part ways. She was sent to a fortress island and began her role as a sorcerer who will stand guard there. He, as a storyteller, began his own journey without her, going from town to town, village and soldier barrack, across the kingdom, telling stories of great men and their deeds, and courageous heroes who fought the war, to uplift the spirit of the people and bring valor to the soldiers stationed at the border and people in the coming war.   In brief, he meets a dragon (who used to be involved in the war in ages past), long thought to be extinct. He finds himself able to communicate with it and has a "born" friendship with it. The dragon teaches him to become a "dragon rider", a long-lost ability of his people (due to the "extinction" of dragons.)   The wind changes with the dread of war hanging on the kingdom.  Airships start to blacken the sky again with soldiers and war machines battling each other. Book about almost extinct warrior race with three castes: sen, kaa, ker The aliens in this book are an humanoid alien mercenary race, fighting for some other aliens, against humans?.   The Ker are the fighters, the sen are the wise ones, and the kaa the family/non-fighters.  Their clan gets almost wiped out because both their employers and humanity fear them, and the last survivors head towards their race' home planet, together with a human captive, who learns about their ways.  The other aliens are some blob-like aliens with little genetic variety.  Ring any bells? Two sidebars in Beamer for two presentations in one tex file Since I updated the system to 10.11.5, the Facebook message notification is not showing message text.   Is this a bug in this software upgrade of OSX? Difference between >>> and >> Update to latest version of java after ppa is discontinued I have been trying to install the latest version of java-8. However, I found out that the  due to changes in the java licence.  How should I update my java to 8.0_201 or 8.0_211 now?  Thanks! Update SQL Server table with local data I'm trying to parse json response.. but keep getting this error      Invalid conversion from runtime type List ANY> to Map String,ANY>   Map&lt;String, Object&gt; MapLv3 = new Map&lt;String, Object&gt;();      Integer x2 = 0; for (Object oh : CallsList){     MapLv3.put(String.valueof(x2), oh);     x2++; } index = x2; System.debug('Map Lv 3 ==&gt;'+MapLv3);  Map&lt;String, Map &lt;String, Object&gt;&gt; Map3 = new Map&lt;String, Map &lt;String, Object&gt;&gt;(); for (Integer a2 = 0; a2 &lt; index; a2++){     Map3.put(String.valueof(a2),(Map&lt;String,Object&gt;) MapLv3.get(String.valueof(a2))); } System.debug('Segment ==&gt;'+Map3.get('0').get('segments'));