How do I get past the Sea Snake?
Is the Eel immortal?
Software/App for electronic research notebooks I want to keep a research notebook for my computational "experiments". Basically, I should at least be able to write text and attach images like plots. Other nice features to have would be   linking to past experiments/pages latex equations uploading papers, or other urls being able to transfer data dating and version control open-source tool   I am already familiar with trello and tiddlywiki. Trello is good for attaching stuff and organising tasks, but I need a notebook where I attach a plot, write stuff around it, attach another below it. It doesn't have a paper or canvas. Tiddlywiki is a little painful for attaching pics and equations, the file bloats, it seems I am keeping a blog.  What is a good, free electronic notebook tool for research/lab work? How to handle UNABLE_LOCK_ROW errors when this is caused by a batch APEX job we are facing a serious issue. We have a batch APEX job running daily which makes updates on records fulfilling certain conditions. There is another job running parallel to this, in some cases updating or accessing to the same records than the batch job and hence, causing the error:     Update failed. First exception on row 400 with id XXX; first error:    UNABLE_TO_LOCK_ROW, unable to obtain exclusive access to this record or 200    records:   So, I had then read that in order to fix this kind of error you should use FOR_UPDATE in your select statement (records that have to be updated). The problem is, that you can not use FOR UPDATE for batch jobs. We tested this and effectively, we get the error:     System.QueryException: Locking is implied for each batch execution and   therefore FOR UPDATE should not be specified      It will however lock the records within each execution of execute. See   QueryLocator.getQuery()usage:      You cannot use the FOR UPDATE keywords with a getQueryLocator query to   lock  a set of records. The start method automatically locks the set   of records in  the batch.   Could you find a solution to this?. We would like to handle this in the code itself, because we don't have the permission to schedule the batch job for another time as the another job. What are the advantages and limitations of dynamic type languages compared to static type languages?  See also:  (a far more argumentative thread...) How to adjust font features in LuaTeX? As of version 2.7 of luaotfload the support for font feature files (.fea) .  On the  Hans showed how to make font substitution work through Lua.  More examples are available in the latest ConTeXt distribution (, , , , , , )  In the past I have been using font feature files to adjust the kerning of fonts on-the-fly.  From Hans' example it is not clear to me how to adjust kerning in the new syntax.  The below example does not work as intended.  \documentclass{article} \usepackage{fontspec} \directlua{ fonts.handlers.otf.addfeature {     name = "kern",     {         type = "pair",         data = {             [0x0041] = { [0x0056] = { false, { -200, 0, 0, 0 } } },         }     } } } \setmainfont{Latin Modern Roman} \begin{document} AV \end{document}   Can we have a comprehensive guide on how to adjust font features with LuaTeX with the fonts.handlers technique?    Related questions:  (These involve hooking into the luaotfload.patch_font callback) This is what I saw when my plane was taxing to the runway at CDG:     Airplane mode was on and all other transmissions (except Location), including WiFi, mobile data, NFC and Bluetooth were off.  Location was not manually turned on by me, after I enabled Airplane Mode. It remained turned on.  What am I missing? Is GPS now so widely accepted on-board planes that Android changed its configuration to let this kind of signal/communication to pass through Airplane mode "block"?  I believe that  isn't a duplicate, because at that time (2016) Location was generally "included" in Airplane mode and was turned off by enabling it. I am using Apache Felix and its Declarative Services (SCR) to wire the service dependencies between bundles.  For example, if I need access to a java.util.Dictionary I can say the following to have SCR provide one:  /** * @scr.reference name=properties interface=java.util.Dictionary */  protected void bindProperties(Dictionary d) { }  protected void unbindProperties(Dictionary d) { }   Now, I have more than one Dictionary service available, and I want to filter them using the "name" service property (I only want "name=myDictionary"). I can do that with code (using a ServiceTracker), but I'd rather specify the filter in the @scr annotation instead. leaflet geojson coordinate problem I just started to play with leflet/geojson a little. But my coordinates are not rendered properly and I have no clue what is going on.  My coordinates are: 52.23943, 4.97599. They work correct with the setView function.  var map = L.map('leaflet_map').setView([52.23943, 4.97599], 15);   But using a geojasonFeature they are, hmmm, 'projected', somewhere east of Somalia.  var geojsonFeature = {             "type": "Feature",             "properties": {             "name": "Coors Field",             "amenity": "Baseball Stadium",             "popupContent": "This is where the Rockies play!"             },             "geometry": {                 "type": "Point",                 "coordinates": [52.23943, 4.97599]             }         };         var myLayer = L.geoJson().addTo(map);         myLayer.addData(geojsonFeature).bindPopup("I am a gjson point.");   Anyone who knows what is happening here?  EDIT  Out of pure curiosity I changed the coordinates around [4.976143930893815,52.23925499011473] and the point appears at its correct location. A known bug!? What is a token? Please forgive such a basic question, but I did some Google searching and looked around on this site,  and while there are many threads and online resources that involve tokens, I can't seem to find a direct explanation of what a token is, specifically in the context of TeX, LaTeX, etc. Perhaps there is a good explanation of tokens in the TeXbook, but I don't have a copy of it.   gives me some idea:     A token is a string of characters, categorized according to the rules as a symbol (e.g., IDENTIFIER, NUMBER, COMMA).   but this is a bit too general for me to understand. Taking a guess based on the Wikipedia definition and , is it correct to say that a token is "a thing that has a catcode"? (which, even if true, does not seem entirely satisfactory as an answer: what characterizes the things that are given catcodes?)  Some illustrative examples, and non-examples, of tokens in the realm of TeX, LaTeX, etc. would be much appreciated. How to get distance when acceleration is not constant? permission reporting on sudoers I'm looking for a good, consistent and easy way to do a report of sudoers permissions for every user and group on the system. For users, I want the report to include permissions granted via group membership. The Stack Overflow search shows questions twice. See  for example.  Results include "A: Add Search Engine into MVC Music Store" and "Q: Add Search Engine into MVC Music Store".  Why is search displaying the question twice, and what does "Q" and "A" mean?  Edit:   @Stephen answer :  The search is returning both a question (Q) and an answer (A) to the question, as both posts match your search criteria.  and my another question  If the question have multiple (like 100) answer ,then the answer link(A: Question Link) shown 100 times?  Is it correct functionality ? But i saw only one answer link , not a other answer link .. why ? How to fully backup non-rooted devices? I know I'm asking for the close-to-impossible -- as a real full-backup certainly requires root permissions. But still there are many folks around not wanting to root their devices -- afraid of voiding their warranties or bricking their devices, or just not having their devices supported by any rooting method.  I also know there were a lot of questions asked already on this topic, and I checked all of them having the backup tag -- none covers the entire topic, all just have pieces, and especially people new to Android (but other non-power-users as well) would have a hard time figuring out the best way.  So I want a detailed canonical answer to the question:  Not involving root-solutions, how to achieve a backup as close as possible to a full backup?  Please do not give simple one-liner answers like "Use app xyz [full-stop]." If mentioning an app (and I doubt a single app would be the answer here), include what parts are covered by it -- as well as ideas on how to fill the gaps it leaves. (And to make it absolutely clear: I know the first thing coming to mind is Titanium Backup -- I use it myself, but this does not apply here: This question is strictly about methods for non-rooted devices!) Moreover, the answer should be as generic as possible in terms of applying to a wide range of devices (i.e. it should not be restricted to one device or manufacturer).  I already mentioned having investigated all questions here tagged backup. These will certainly be helpful providing details for answers here, so I will list up the topmost ones concerning my question:            All these provide some details for my question (so feel free to get inspired by them) -- but I feel there are still details missing. Also it would be helpful to have a summary -- say, an answer including the full description of "the maximum possible".  A last criterium: While I'd consider cloud-based solutions legit, I'd favour local solutions. If you can provide both: all the better. But some people value privacy quite high (I'm one of them), and thus would not trust their data to some cloud service.    Thanks to Ryan, we now have a solution for a really complete backup of all apps and their data -- which I didn't dare to hope for! The only disadvantage: His solution only works for less than 10% of all Android users; namely those whose devices are running at least with Android 4.x.  So again, I ask the close-to-impossible: Any solutions applicable at least on Gingerbread (2.3.x) or, better, even Froyo (2.2.x) -- so they cover the majority of current devices? These solutions may involve multiple tools (try to keep it as simple as possible though; think of your mother to follow your instructions ;)  And keep in mind: NO ROOT!    To further motivate high-quality answers (and hopefully avoid low-quality ones), I will be a harsh one here: As I rarely do, I will down-vote answers not fitting the mentioned criteria on one end -- but on the other end, I will setup a bounty for the best answer (which cannot be done immediately, but earliest after 2 days). I've installed reCAPTCHA module but spam still bypass my security and leave nasty comments. What should I do? How to block them? Possible Duplicate:          There are a lot of really screwed up configurations out there, because people didn't take a minute to sit down and think about something as simple as the name for their Active Directory forest. I'm asking this question to self-answer so that this knowledge can be more readily available. If you think you have a better answer, by all means add your input (but be prepared to defend it!)   So, what should I name my new Active Directory? I need to sync the Downloads folder to iCloud and then all the downloads should automatically sync with iCloud.   I tried to:   Create a new Downloads folder in the terminal of MacBook in the Documents directory. Tried to move the default Download folder to the newly created folder.   When I tried to use the mv command to move the default Downloads folder to the newly created Downloads folder in Documents in the terminal, it gives permission denied error.  I am trying to achieve what was suggested by user PhillipHolmes in the below thread, please. Thank you:    Thank you makefiles CFLAGS In the process of learning tinyos I have discovered that I am totally clueless about makefiles.  There are many optional compile time features that can be used by way of declaring preprocessor variables.  To use them you have to do things like:  CFLAGS="-DPACKET_LINK"        this enables a certain feature.  and    CFLAGS="-DPACKET_LINK" "-DLOW_POWER" enables two features.  Can someone dissect these lines for me and tell me whats going on? Not in terms of tinyos, but in terms of makefiles! I have problems transferring binary programs to a micro-controller prototype board when using ubuntu/kubuntu to mount the board via usb. With MacOS and Windows there are no problems. I have found the writing from Ubuntu definitely changes the written file. I suspect that the write caching is the problem. How can I disable it, or what else might be the problem. Show $\lim_{h\to 0} \frac{(a^h-1)}{h}$ exists without l'Hôpital or even referencing $e$ or natural log Time-ordered operator in Srednicki , "Note that the operators are in time order...we can insert $T$ without changing anything". This I agree with. But then on the next paragraph he states "The time order operator $T$, moves all...where they annihilate...". How correct is this paragraph? Is equation (5.14) always valid? Is equation (5.14) the reason why the time-ordering symbol $T$ appears all over the place in QFT?  The equations I'm referring to are (braket package available?):   $$\langle f|i\rangle = \langle0|~a_{1'}(+\infty)a_{2'}(+\infty)a_{1}^\dagger(-\infty)a_{2}^\dagger(-\infty)~|0\rangle \tag{5.13} $$  and since time goes from right to left inside the braket we put the $T$-symbol  $$\langle f|i\rangle = \langle 0|T ~a_{1'}(+\infty)a_{2'}(+\infty)a_{1}^\dagger(-\infty)a_{2}^\dagger(-\infty)~|0\rangle \tag{5.14} $$   without changing anything.   After this, the $T$-symbol appears everywhere! How to stop constantly blinking Wifi LED?