I'm playing with migrations from D7 to D8 and I've found that, when you register a module with a migration, if you disable it, next time you enable the module gets stuck on this:  [vagrant@devbox] /[...]/default $ drush en progweb_migration -y PHP Warning:  Module 'imagick' already loaded in Unknown on line 0 PHP Warning:  Module 'imagick' already loaded in Unknown on line 0 The following extensions will be enabled: progweb_migration Do you really want to continue? (y/n): y exception 'Drupal\Core\Config\PreExistingConfigException' with message 'Configuration objects[error] (migrate.migration.custom_user) provided by progweb_migration already exist in active configuration' in /www/drupal8/core/lib/Drupal/Core/Config/PreExistingConfigException.php:70 Stack trace: #0 /www/drupal8/core/lib/Drupal/Core/Extension/ModuleInstaller.php(162): Drupal\Core\Config\PreExistingConfigException::create('progweb_migrati...', Array) #1 /opt/drush7/vendor/drush/drush/commands/core/drupal/environment.inc(129): Drupal\Core\Extension\ModuleInstaller->install(Array, true) #2 /opt/drush7/vendor/drush/drush/commands/core/drupal/environment.inc(196): drush_module_install(Array) #3 /opt/drush7/vendor/drush/drush/commands/pm/pm.drush.inc(1120): drush_module_enable(Array) #4 [internal function]: drush_pm_enable('progweb_migrati...') #5 /opt/drush7/vendor/drush/drush/includes/command.inc(359): call_user_func_array('drush_pm_enable', Array) #6 /opt/drush7/vendor/drush/drush/includes/command.inc(210): _drush_invoke_hooks(Array, Array) #7 [internal function]: drush_command('progweb_migrati...') #8 /opt/drush7/vendor/drush/drush/includes/command.inc(178): call_user_func_array('drush_command', Array) #9 /opt/drush7/vendor/drush/drush/lib/Drush/Boot/DrupalBoot.php(46): drush_dispatch(Array) #10 /opt/drush7/vendor/drush/drush/drush.php(76): Drush\Boot\DrupalBoot->bootstrap_and_dispatch() #11 /opt/drush7/vendor/drush/drush/drush.php(16): drush_main() #12 {main}   It's like the migration is being registered but not de-registered. In D7 there is a method for that, but no luck so far trying in D8:  function progweb_migration_enable() {   Migration::registerMigration('custom_user');   Migration::registerMigration('custom_blog');    Migration::registerMigration('ProgwebBlog');   Migration::registerMigration('ProgwebUser'); }  function progweb_migration_disable() {   Migration::deregisterMigration('custom_user');   Migration::registerMigration('custom_blog');    Migration::deregisterMigration('ProgwebBlog');   Migration::registerMigration('ProgwebUser');  }   Any ideas?

I'm writing a custom module for Drupal 8. It defines a field storage configuration object, in a file called modules/mymod/config/install/field.storage.bloom_stem.bs_twitter_ac.yml.  The problem is that this is not removed when I uninstall the module; it is apparently left behind because, when I re-install the module, I get a crash.   drush -y pm-uninstall mymod drush cr drush -y en mymod      exception 'Drupal\Core\Config\PreExistingConfigException' with message 'Configuration objects (field.storage.bloom_stem.bs_twitter_ac) provided by mymod already exist in active configuration'   So it seems I need to some how manually remove this configuration object. Do I need to provide some more code that deletes it when the module is uninstalled?


I have download Scrivener Appimage on Ubuntu 20.04 but it not integrate on the menu using Appimage Launcher. What’s the problem? Settings on the launcher or the application? Hope for some help Thanks Josef

How can I register an .appimage file (specifically, the tiled map editor found ) as a desktop app? (Like firefox -- I can launch it by typing 'Firefox' into search rather than opening up a console and typing /path/to/directory/firefox.ext)


I just bought an galaxy s7 edge, and this weird icon is on my notifcation bar. I cannot seem to figure it out.  Does anyone know what it does or means? Thanks.

I'm using Samsung Galaxy Note 5 on Android Marshmallow. I was just wondering what that oval-shaped symbol near the top center was.


I am very new to Ubuntu and I have encountered a problem where I cannot connect to the internet through both wifi and ethernet. I am using a B550m-plus gaming wifi motherboard and I have Ubuntu 20.04 installed onto my E drive. I wanted Ubuntu to be a stand-alone drive instead of mixing it with Windows on my other drives. Upon log-in, the only thing I see in networks settings are options to connect to a VPN. I have no option to connect to either ethernet or wifi, which are available since I can connect to both when I am on Windows. The network icon that is supposed to be available at the top right corner is missing too. I've looked through various sources and they pointed me towards having missing chipset drivers. So I followed the instructions to Realtek and downloaded the "2.5G Ethernet LINUX driver r8125" driver. Unfortunately, what followed was a flurry of missing drivers that I could not install because I have no internet connection. Any tips on how to solve this? Edit: here are some pictures which show what I am seeing.

So I did a fresh install of Ubuntu 20.04 on a computer with the new RTL8125B Realtek network card and I cannot get the network to work. I was very suprised since this is supposed to be the new feature of the 5.4 kernel (I have 5.4.0-26-generic installed). Does anyone have any idea on how to get it working? Thank you. $ lspci -knn | grep Eth -A3 06:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller [10ec:8125] (rev 04) Subsystem: ASUSTeK Computer Inc. RTL8125 2.5GbE Controller [1043:87d7] Kernel modules: r8169 07:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/570X/580/580X/590] [1002:67df] (rev e7)  $ dmesg | grep -i r8169 [    0.911236] r8169 0000:06:00.0: unknown chip XID 641


Can we find a monotone function $f:[0,1]\rightarrow\mathbb R$ whose discontinuity set is exactly the set $\mathbb Q\cap [0,1]$? Or can we prove that such a function does not exist?

Can we construct a monotonic function $f : \mathbb{R} \to \mathbb{R}$ such that there is a dense set in some interval $(a,b)$ for which $f$ is discontinuous at all points in the dense set?  What about a strictly monotonic function?   My intuition tells me that such a function is impossible.  Here is a rough sketch of an attempt at proving that such a function does not exist: we could suppose a function satisfies these conditions.  Take an $\epsilon > 0$ and two points $x,y$ in this dense set such that $x<y$.  Then, $f(x)<f(y)$ because if they are equal, then the function is constant at all points in between, and there is another element of $X$ between $x$ and $y$, which would be a contradiction.  Take $f(y)-f(x)$.  By the Archimedean property of the reals, $f(y)-f(x)<n\epsilon$ for some $n$.  However, after this point, I am stuck.  Could we somehow partition $(x,y)$ into $n$ subintervals and conclude that there must be some point on the dense set that is continuous?


I am new bee for Linux. I have a question about the command find. When I search a file under a directory, I would like to skip a sub-directory named publish  find ./ -path ./publish -prune -o -iname rdesvc -type f -print   It works fine:  ./release/apps/rdeSvc/server/linux/rdeSvc   But, if I remove the parameter -print:  find ./ -path ./publish -prune -o -iname rdesvc -type f   It will output the sub-directory name with the search result:  ./publish ./release/apps/rdeSvc/server/linux/rdeSvc   I feel confusion. Why the sub-directory name publish is outputted if I removed the parameter -print?  My distribution is CentOS 6.6 64 bit.

When I'm using  find . -type f -name "*.htm*" -o -name "*.js*" -o -name "*.txt"  it finds all the types of file. But when I add -exec at the end:  find . -type f -name "*.htm*" -o -name "*.js*" -o -name "*.txt" -exec sh -c 'echo "$0"' {} \;  it seems it only prints .txt files. What am I doing wrong?  Note: using MINGW (Git Bash)


Here is a code which I have written. I have got some logical error in it.  typedef struct bigint_ {  int signbit; int*ptr;  } bigint; void print_bigint(bigint big_num); bigint shift_by_power_of_10(bigint big_num, int d);  main() { bigint a; bigint b; a.ptr=malloc(6*sizeof(int)); a.ptr[0] = 1; a.ptr[1] = 2; a.ptr[2] = 2; a.ptr[3] = 2; a.signbit = 0; b=shift_by_power_of_10(a,3); print_bigint(b);  } bigint shift_by_power_of_10(bigint big_num, int d) { int len = (int)(sizeof(big_num.ptr)/sizeof(int)); printf("%d\n",len); big_num.ptr = realloc(big_num.ptr,d*sizeof(int)); int i; for (i=len;i<len+d;i++) {     big_num.ptr[i] = 0; } return(big_num);  } void print_bigint(bigint big_num) { int i; if (big_num.signbit == 1) {     printf("-"); } int len = (int)(sizeof(big_num.ptr)/sizeof(int)); for (i=0;i<len;i++) {     if (i!=len-1)     {         printf("%d",big_num.ptr[i]);     }      else     {             printf("%d\n",big_num.ptr[i]);     } }    }   In function shift_by_power_of_10() while printing len, I should have got 4,but I am getting len as 2.   Can you please point out the logical error in it.

I've allocated an "array" of mystruct of size n like this:  if (NULL == (p = calloc(sizeof(struct mystruct) * n,1))) {  /* handle error */ }   Later on, I only have access to p, and no longer have n. Is there a way to determine the length of the array given just the pointer p?  I figure it must be possible, since free(p) does just that. I know malloc() keeps track of how much memory it has allocated, and that's why it knows the length; perhaps there is a way to query for this information? Something like...  int length = askMallocLibraryHowMuchMemoryWasAlloced(p) / sizeof(mystruct)   I know I should just rework the code so that I know n, but I'd rather not if possible. Any ideas?


I got $ab^3=b^2a$ and $a^2b=ba^3$ by getting rid of the inverses via composing on both sides.   I tried writing $a=aaa^{-1}$, which didn't help. Any suggestions please?

Suppose $a$ and $b$ are elements of a group $G$. If $a^{-1}b^{2}a=b^{3}$ and $b^{-1}a^{2}b=a^{3}$, prove $a=e=b$.   I've been trying to prove but still inconclusive. Please prove to me.  Thanks very much for proof.


I apologize if this question has been asked before, I wasn't able to find anything that exactly fit what I was trying to do. I'm attempting to change my citations in order to display the page number following the year and a colon. For example, I am using:  \parencite[27-45]{key}   And expecting to get the citation (Dasgupta & Nino, 2009:27-45), but instead get (Dasgupta & Nino, 2009, pp. 27-45).  I have tried using the \cite{} and \citep{} commands with various settings that I found while searching this site but to no avail.  A minimal working example that should demonstrate the problem appears below. I am using babel, csquotes, and biblatex with style=apa, and biber as a backend with the natbib compatibility option.  My .tex with all packages that I am using:  \documentclass[12pt, a4paper]{article} \usepackage[english, american]{babel} \usepackage{csquotes} \usepackage[%     style=apa,backend=biber,natbib     ]{biblatex} \DeclareLanguageMapping{english}{american-apa} \setlength{\parskip}{1em} \addbibresource{./ref.bib}  \begin{document}      \parencite[27-45]{immunological-computation}  \printbibliography \end{document}   And an example from my .bib file:  @Book{immunological-computation,     Title                    = {Immunological computation},     Author                   = {D. Dasgupta and L. F. Nino},     Publisher                = {CRC Press},     Year                     = {2009},     Place                    = {Boca Raton} }   Any help with this would be appreciated, so thank you in advance.

In the question , I learned how to remove a postnote delimiter when the citation doesn't contain a numeral, by adding this to the preamble:  \renewcommand{\postnotedelim}{\iffieldnums{postnote}{\addcolon}{\addspace}}   However, this also removes the delimiter between a regular citation and a "comment" style citation (such as "NN p.c.") (cf. ).  The question is, how do I make sure that the delimiter between the "regular" citations and the "comment" is the same character (comma, semicolon) as used to delimit the "regular" citations?  \documentclass{article} \usepackage[style=authoryear]{biblatex} \DeclareFieldFormat{postnote}{#1} \renewcommand{\multicitedelim}{\addcomma\space} \renewcommand{\postnotedelim}{\iffieldnums{postnote}{\addcolon}{\addspace}} \usepackage{filecontents} \begin{filecontents}{\jobname.bib} @book{lennon1972,     AUTHOR = "John Lennon",     TITLE = "Who did what in the Beatles",     YEAR = "1972"} @book{starkey1994,     AUTHOR = "Richard Starkey",     TITLE = "I'm the drummer",     YEAR = "1994"} @ONLINE{archiveZ,     TITLE = "Archive Z",     SHORTHAND = "Archive Z",     URL = "http://www.archivez.com",     URLDATE = "2013-03-22"} \end{filecontents} \addbibresource{\jobname.bib}  \begin{document} I know from books and people I have talked to that George Harrison played the guitar in the Beatles \parencites(Paul McCartney p.c.) [48]{lennon1972}[103]{starkey1994}[no. 58]{archiveZ} \end{document}     The citation should ideally look like this:     (Lennon 1972:48, Starkey 1994:103, Archive Z no. 58, Paul McCartney p.c.)


As far as I know, in English titles each word should be capitalized.  Should each word of the text in buttons be capitalized if it is a title (e.g. "Add Job Offer"), or should the button text be treated the same as a sentence when there are more than one word (e.g. "Add job offer")?

I am wondering if we should use  or  for buttons and headings in websites and web/mobile apps? Title Case: Manage my Account Delete my Account  Sentence case: Manage my account Delete my account  In  I found the recommendation 'choose your style and be consistent'. This is it? Aren't there any other (additional) recommendations or sources. Like for specific use cases or apps where the one style would be preferred over the other? Edit: The question refers primarily to English, but differences in other languages are also good to know.


If I purchase a Windows home license, how long would it be supported for?  I remember, Microsoft announced, that there will be no more Windows 11 after Windows 10 and that Windows will just receive rolling updates again and again. But at the same time their website says that Windows 10 end of mainstream support (Bug fixes, features etc) is October 13, 2020. How these two correlate?  It seems surprising that you will get a perpetual Windows 10 license with all future updates ever coming out, right?  It's more clear with Microsoft Office, which .  Does Microsoft have any official, canonical documents on this?

Windows 10 has been referred as  based on paradigm “Windows-as-a-service”, an ongoing product, constantly updated, with both patches and new features added on over time.  In contradiction to the above statement,  says that Windows 10 will reach end of life on 2025-10-14.  These statements seem contradicting.  If the latter is true, it could still be better to purchase OEM Windows with new computer (the same way as before Windows 10) because there will be no need to keep it longer than the computer.  But if the first statement is true, more costs could be saved by purchasing retail version of Windows 10 and just migrating it between computers with each purchase of the new computer.  Which of the above Microsoft statements should be trusted in relation to choosing Windows 10 license?


When $n=2$ we know that  $n^2-1$ is prime but is this the case, when $n>2$?

Prove that there doesn't exist integer $x \ge 3$ such that $x^2-1$ is prime.


-I am trying to extract data of contacts who entered the journey and who exit the journey as a reminder group and passed through wait by duration activity before flowing out of journey.  -These contacts are not a part of any activity like email. -I am trying to query in data views and not able to find any table when this information is capture. Can anyone help with a query to identify these contacts.

What ways could you create a data extension that contains all the subscribers (SubscriberKeys) that are currently “in” a Journey (Journey Builder)?  The Journey I would like to do this for is a complex activity with multiple decision branches resulting in multiple possible journey durations. For example; if the customer didn’t open Email1 after 2 days, then send Email2; else Exit Journey. If the customer didn’t open Email2 after 2 days, then send Email3; else Exit Journey. Wait 2 more days, then End Journey. The minimum journey duration for the above example is 2 days, while the maximum is 6 days.  Note that I don’t want a list of subscribers that “entered” a Journey, but a list of the ones that are “currently in” a Journey and have not yet exited. Answer must account for non-standard Journey exits including Unsubscribes/Contact Deletes, etc.


I believe that I read this in the early 2010s when I was in New Jersey, although I might have read it as far back as the early 2000s when I was in Ohio (I remember checking it out from the library and reading it in my apartment, but I don't have a firm memory of the location). A female researcher is stranded on an alien planet, specifically in a jungle that's incredibly deadly due to environmental poisons and dangerous beasts. The local sapient aliens take pity on her and turn her into one of them. The aliens are quadrupedal with long tails, I think more like cats or lizards than monkeys. Their skin changes colors, I think both for camouflage and to express emotions. Eventually, other humans return to find her, and she's confronted with the question of whether she can become human again, and if she even wants to.  It was a B-format or Trade paperback, primarily white in color. I remember that the cover was almost garishly colorful, all primary colors, I think depicting the jungle itself. I think the title was four words, in the form of "The X of Y". For some reason, "The Color of Passion" comes to mind, but searching on that doesn't get me anything useful.

I have been trying to figure this out for years. There is another posting that is similar, but I'm not sure if it's the same.   Female protagonist, I don't remember how she finds herself on the alien planet, but she is injured or stranded or something so the aliens transform her into one of them. From what I recall they are frog like, forest dwelling, and I vaguely recall telepathic communication?   At some point there are other humans, and she turns back into a human. I remember a really bizarre, out of place, graphic sex scene with a fellow human.  Also for some reason I keep thinking the author was maybe Swedish or Danish?


Hear me out. I know there's a "panoramic" mode for cameras now. Thing is, it only works with Cycles. Cycles does not support some things, like particles (halo, line). I need particles, I also need to render an equirectangular render of the scene.  What can I do? Even some mulitple camera setup + external tool would work. Note that I need animations though, an image editor won't do.

Can such frames/videos be rendered in Blender Internal as well? If not, how indirectly?  EDIT: The below solution is great as long as you can write your own Python script and only render solid objects. When you need things like particles/hair, it won't work as those won't be reflected.


Suppose that we have 30 plants (that are the same exact plants). Suppose that we choose 15 out of a sample of 30 plants and we seeded them with a drag. We then want to test whether this drag has an effect of making them grow faster. So we have 15 plants with a drag, and 15 plants with no drag.   Let's suppose that the weather conditions are the same and they are at the same exact place-location. Are they paired or unpaired? Before I ask this question I searched it and by definition:  Paired samples mean that we take a sample (let's say a plant) and we see how it grows, then we put the drag to the EXACT same plant and see whether it makes any difference. According to this definition, I would use UNpaired samples since I am choosing two different groups of plants and not the same plant each time. BUT, concerning the fact that all these 30 plants are the same (they are the same object) can I still use a paired t-test? Thank you, I hope my question makes sense.   I read many examples with animals or humans. Of course if we have humans or animals then of course the answer is very simple, since every animal or human being is different. Subsequently if I use two different groups of human for example, the samples could be unpaired. But when I use objects like plants or clouds or trees or something like that. Does it make any sense to consider them as different, avoiding the fact that we are talking about the same object.

Suppose I have 20 mice. I pair the mice in some way, so that I get 10 pairs. For the purpose of this question, it could be a random pairing, OR it could be a sensible pairing, like trying to pair mice from the same litter, of the same sex, with similar weight, OR it could be a deliberately stupid pairing like trying to pair mice with weights as unequal as they could possibly be. I then use random numbers to assign one mouse in each pair to the control group and the other mouse to the to-be-treated group. I now do the experiment, treating only the to-be-treated mice, but otherwise paying no attention whatsoever to the arrangements just made.  When one comes to analyze the results, one could either use unpaired t-testing or paired t-testing. In what way, if any, will the answers differ? (I'm basically interested in systematic differences of any statistical parameter that needs to be estimated.)  The reason I ask this is that a paper I was recently involved with was criticized by a biologist for using a paired t-test rather than an unpaired t-test. Of course, in the actual experiment, the situation was not as extreme as the situation I've sketched, and there were, in my opinion, good reasons for pairing. But the biologist didn't agree.  It seems to me that it's not possible to incorrectly improve statistical significance (decrease p-value), in the circumstances I sketched, by using a paired t-test, rather than an unpaired test, even if it is inappropriate to pair. It could however worsen statistical significance if mice were badly paired. Is this right?


I have a method that accepts a generic TViewModel class like so:  Page GetPage<TViewModel>() where TViewModel : class, IViewModelBase;   In my class I get the type of the item that the user selected (from a navigation list) like so:  var viewModel = item.TargetType;   This type will always be a view model that inherits from IViewModelBase   When I call this next line I need to be able to pass in the viewModel type. Im trying to do   var page = Navigator.GetPage<viewModel>();   But I get the following error:      viewModel is a variable but is being used like a type.   Is there anyway I can pass the viewModel type to the GetPage Method?  If not the only way I can see to do this is to have a switch statement that checks the viewModel type name and hard code the correct TViewModel into the GetPage call.  For example something like this:  switch (viewModel.Name) {     case "TaskViewModel":             page = Navigator.GetPage<TaskViewModel>();        break;     case "TaskEditViewModel":             page = Navigator.GetPage<TaskEditViewModel>();        break; }   I tried the solution that this was marked as a duplicate for and that answer does not apply to mine. I get the error      Object does not match target type   The attempted code looks like this:  MethodInfo method = typeof(Navigator).GetMethod("GetPage"); MethodInfo generic = method.MakeGenericMethod(viewModel); generic.Invoke(this, null);

What's the best way to call a generic method when the type parameter isn't known at compile time, but instead is obtained dynamically at runtime?  Consider the following sample code - inside the Example() method, what's the most concise way to invoke GenericMethod<T>() using the Type stored in the myType variable?  public class Sample {     public void Example(string typeName)     {         Type myType = FindType(typeName);          // What goes here to call GenericMethod<T>()?         GenericMethod<myType>(); // This doesn't work          // What changes to call StaticMethod<T>()?         Sample.StaticMethod<myType>(); // This also doesn't work     }      public void GenericMethod<T>()     {         // ...     }      public static void StaticMethod<T>()     {         //...     } }


Proposition. $\lambda [0,1] = 0$   Proof. Let $\varepsilon>0$ be arbitrary. We will prove that $\lambda[0,1] <\varepsilon$. Let $q : \mathbb{N} \rightarrow \mathbb{R}$ denote an injection with image equal to $\mathbb{Q} \cap [0,1]$. Let $p : \mathbb{N} \rightarrow \mathbb{R}_{>0}$ denote a sequence with $\sum_{i \in \mathbb{N}} p_i < \varepsilon$. Then $$\lambda [0,1] = \lambda \bigcup_{i \in \mathbb{N}} (q_i+[-p_i/2,p_i/2]) \leq \sum_{i \in \mathbb{N}} \lambda (q_i+[-p_i/2,p_i/2]) = \sum_{i\in \mathbb{N}} p_i < \varepsilon$$  So $\lambda[0,1] < \varepsilon$. Since this is true for all $\varepsilon>0$, we deduce that $$\lambda [0,1] = 0.$$     Question. What gives?

Consider $\mathbb{Q}$ which is countable, we may enumerate $\mathbb{Q}=\{q_1, q_2, \dots\}$. For each rational number $q_k$, cover it by an open interval $I_k$ centered at $q_k$ with radius $\epsilon/2^k$.  The total length of the intervals is a geometric progression that sums up to $\epsilon$.  Each real number is arbitrarily close to a rational number since $\mathbb{Q}$ is dense in $\mathbb{R}$. Thus, each real number is in one of the open intervals.  Thus the entire real line is covered by the union of the $I_k$, thus $\mathbb{R}$ is a null set with measure zero.  Clearly there is something wrong in the above proof, however I am not sure where is it?  Thanks for any help.


Doing a python problem and trying to create a new string that omits a single char at index n. This works: newstr = str[:n] + str[n+1:]  but wondering why this didn't work: newstr = str[:n] + str[-1:-(n+1)]  Thanks in advance^

I need a good explanation (references are a plus) on Python's slice notation.   To me, this notation needs a bit of picking up.   It looks extremely powerful, but I haven't quite got my head around it.


I have applied for an Indian tourist visa not knowing I clicked travel by road via Haridashpur. Am I still able to travel by air?

I am from Bangladesh, and I have an Indian tourist visa, which I received from the Indian High Commission in Bangladesh. At this moment I am in Bhutan. Now I want to enter India by air. Is it possible? And will I face any problems when I come back from Kolkata to Dhaka?


I've been learning programming in python for the last two weeks and it's going great so far. But now I'm stuck and can't seem to find an answer. I found a really weird behaviour of a while loop, I just can't wrap my head around.  x=0 step_size=0.2  while x<2:     print x     x+=step_size   This code prints:  0 0.2 0.4 ... 1.8 2.0   2.0 should not be printed, right? When x becomes 2.0 the statement "x<2" is false, therefore the loop should exit and never print 2.0.  And now for the really weird part: it works with other numbers. Step_size=0.4 prints up to 1.6, step_size=0.1 up to 1.9. Using "x<1" as a statement and step_size=0.2 also works.  What am I missing?  Best regards, Leo  Edit: I'm using python 2.7.5 and the default Idle Editior v2.7.5

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


I want to know clearly the real concept of inertia.I have seen lot of definitions regarding inertia.But I could not exactly find real meaning of inertia.

The definition of  is  "Inertia is the resistance offered by the body whenever its state of motion is changed."   What is inertia of a body? Is inertia actually a force exerted by the body?  If so, then why is there no application of inertia in numerical problems involving application of force on a body? What is the actual application of inertia in theory?


What is difference between a DateTime and a DateTimeOffset object?   And when should we use each one?   In a web-application that may change the server's area, storing date and time.  Which one is better, or is there any other suggestions?

A few months ago I was introduced to the new  type and was glad 's flaws with regard to time zones were finally taken care of.  However, I was left wondering if there were any overhead or problems that could occur from using this new type.  I work on a multi-locale web application. Does anyone know of anything that could sway me from just using it for all my date/time work? Is there a window for abuse here?  Reference:


I am working on a class to read data from Excel files using the Apache POI. Specifically, I want to loop over entries in the first column until cells are emtpy. I just figured that the following code gives me a null exception:  while(sheet.getRow(i).getCell(0) != null) {       // Do something       i++; }   However, after changing the code just by removing the getCell(0) it works perfectly fine without the null exception:  while(sheet.getRow(i) != null) {       // Do something       i++; }   In either case I should get back null and then terminate the while loop. Why is the second example working without a null exception? I just don't see the reason.

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I'm studying a branch of philosophy, which is theory of knowledge and I need to investigate this question. I think that in art, it is difficult to say there is progress... whereas natural sciences have. However, I'm still confusing...

I'm studying a branch of philosophy that is concerned with knowledge. I'm studying theory of knowledge(epistemology) and I want to use faith, reason, and memory as tools for carrying this investigation.


In my work (lab research), I have need to take digital photos of thin transparent gels sitting on and being illuminated by a white light box.  When I try to take a digital photo, weird orange bands appear in the image.  These orange bands are not visible to the naked eye, but they appear in digital images taken using both Samsung and Apple smartphones.  We know nothing about photography, so all our images have been made using the phones' default camera settings.  To get rid of these orange bands, do I need to change some setting on the camera?  Would some kind of filter get rid of these (even though, again, they aren't visible to the eye)?  Any suggestions would be most welcome, because we are at a loss about what to do.

Yesterday I took photos of an event at school.  The lighting was poor so I increased the iso to 3200, shutter speed was between 80 and 250 and the aperture between 2.8 and 4.0.  Canon EOS500  about 10% of the photos got this weird horizontal black area. The position of the black area is not the same,  Sometimes it is in the middle, sometimes it is in the upper or lower part of the frame  Is this an artifact from the lighting frequency? or can it be a shutter problem?


My question is a duplicate of this; . The accepted answer from the link above says that at sunset the scattering occurs farther away and does not reach the observer, which is unsatisfactory and vague to me. (not even sure if it's the right and correct answer)  It doesn't quite make sense to me that at noon, we see scattered blue light whereas, at sunset, we see the sunlight itself minus the scattered blue light. At noon or at sunset, we are not seeing the sun, but the scattered sunlight indirectly. The logic should apply both cases equally and should imply that at sunset we see bluer sky than at noon because of more scattering.  Please let me know if this duplicate question was unnecessary because the accepted answer from the link above was enough to answer the question.

(I know Rayleigh scattering isn't the only reason why the sky is blue but to simplify the question lets focus on that)  The commonly stated reason for why the sky is blue is that smaller wavelengths are scattered more easily off the molecules in the air. During the day, because the blue light is scattered more, the sky is illuminated more with that blue light and more reaches your eyes. However, during sunsets and sunrises, the light from the sun must travel a longer distance. The explanation I have found is that the blue light is scattered away and more of the longer wavelength reds and greens are available to reach your eyes to get those warmer colors, (red and green of course mixing to get yellows).   My question is that it seems like these explanations are conflicting. If the light at sunsets and sunrises travels more distance, why won't the blue light be scattered even more and thus illuminate the sky with blue light more than in the daylight? It confuses me that in one case the scattering of blue light causes the sky to be blue but then at sunset the scattering eliminates this color. Could I get some explanation on this?


I have to add numbers with this script:  for(i=1; i<1000 ;i++) sum=sum+i;   it will overflow at 32768 and after that it goes to -32768 because it cant exceed the 16 bit limit.   i want to count the overflows with an int c.   Thanks

I was writing a program in C++ to find all solutions of ab = c, where a, b and c together use all the digits 0-9 exactly once. The program looped over values of a and b, and it ran a digit-counting routine each time on a, b and ab to check if the digits condition was satisfied.  However, spurious solutions can be generated when ab overflows the integer limit. I ended up checking for this using code like:  unsigned long b, c, c_test; ... c_test=c*b;         // Possible overflow if (c_test/b != c) {/* There has been an overflow*/} else c=c_test;      // No overflow   Is there a better way of testing for overflow? I know that some chips have an internal flag that is set when overflow occurs, but I've never seen it accessed through C or C++.    Beware that signed int overflow is undefined behaviour in C and C++, and thus you have to detect it without actually causing it. For signed int overflow before addition, see .


I'd like to have normals spaces in a specific frame. Or, i've got some huge and hugly spaces. Here is a picture.    I've tried [t, allowframebreaks=.70] without succes. Here is my code.  \documentclass[c]{beamer} \usepackage[latin1]{inputenc} \usepackage[T1]{fontenc} \usepackage[french]{babel} \setbeamertemplate{frametitle continuation}{}  \begin{document} \begin{frame}[allowframebreaks=.70] \frametitle{Plan} \tableofcontents \end{frame}     \section{a} \begin{frame} aaa \end{frame} \section{b} \begin{frame} bbb \end{frame} \section{c} \begin{frame} ccc \end{frame} \section{d} \begin{frame} ddd \end{frame} \section{e} \begin{frame} eee \end{frame} \section{f} \begin{frame} fff \end{frame} \section{g} \begin{frame} ggg \end{frame} \section{h} \begin{frame} hhh \end{frame} \section{i} \begin{frame} iii \end{frame} \section{j} \begin{frame} jjj \end{frame} \section{k} \begin{frame} kkk \end{frame} \section{l} \begin{frame} lll \end{frame} \section{m} \begin{frame} mmm \end{frame} \section{n} \begin{frame} nnn \end{frame} \section{o} \begin{frame} ooo \end{frame} \section{p} \begin{frame} ppp \end{frame} \end{document}

In beamer, I guess, the separation space between the items from tableofcontents is stretchable:    Can you set it to a fixed value? e.g. to equal the value used in the itemize environment.  Partial answer:  \begin{minipage}{\textwidth}    \linespread{1.4}    \tableofcontents \end{minipage}   Could someone patch this command with etoolbox and make it happen whenever typing only \tableofcontents? Thanks!  Here is a MWE (with default theme):  \documentclass{beamer}  \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage{lmodern} \usepackage[english]{babel} \usepackage{lipsum}   \title{Whatever Title Works} \author{Remus M. Prunescu$^1$} \institute{\tiny$^{1}$ Automation and Control Group, Department of Electrical Engineering, Technical University of Denmark (DTU)}  \begin{document} \frame{     \maketitle }   \frame{     \frametitle{Outline}     \begin{minipage}{\textwidth}        \linespread{1.4}        \tableofcontents     \end{minipage} }  \section{Introduction} \frame{     \frametitle{Random}     \lipsum[1] }  \section{Project Description} \frame{     \frametitle{Random}     \lipsum[2] }  \end{document}


Full question: Suppose that $f'$ exists and is continuous on $[a, b]$ and $f''$ exists on $(a, b)$, where $a < b$. Show that there exists a number $c \in (a, b)$ such that $$ f(b) = f(a) + (b-a)f'(a) + \frac{(b-a)^2}{2}f''(c) $$ Manipulating the above equation gives me \begin{align*} \frac{f(b) - f(a)}{b - a} &= f'(a) + \frac{(b-a)}{2}f''(c) \\ f'(c) &= f'(a) + \frac{(b-a)}{2}f''(c) \end{align*} The question suggests the use of the Mean Value Theorem. Using this for both $f$ and $f'$ gives me \begin{align*} f'(c) &= \frac{f(b) - f(a)}{b - a} \\ f''(c) &= \frac{f'(b) - f'(a)}{b - a} \end{align*} But I am stuck here. I tried formulating the equation of the tangent line through $(a, f(a))$ for $f$ as well as through $(a, f'(a))$ for $f'$ but to no avail. Is there some sort of manipulation for this which can help?

I started reading "The Mathematics of nonlinear Programming - AL peressini" recently.  Theorem : Suppose that $f(x) , f'(x) ,f''(x)$ exist on the closed interval $[a,b]$. If $x^* ,x $ are two different points of $[a,b]$ , then there exists a point $z$ strictly between $x^*$ and $x$ such that   $$f(x)=f(x^*)+f'(x^*)(x-x^*)+\frac{f''(z)}{2}(x-x^*)^2$$  I tried to prove this theorem using The Fundamental theorem of calculus. But I can not stop it at the second derivative . Do I have to use mean value theorem ? or is there a simple proof for this ?


I start with knowing that two numbers are coprime if:  $n*k + m*j = 1$  So, setting $k = a$ and j = $a+1$ I can solve as follows:  $n*a + m*a + a$  Then,  $a(n+m) + m = 1$  Where can I go from here?

I have a question.  I have been given this proof: "For any $n$ in the integers where $n>2$, show there are at least $2$ elements in $U(n)$ that satisfy $x^2=1$."  I have gone through and actually proved this, (that the numbers are $1$ and $n-1$) but i didn't' know how to prove that $n-1$ is in fact in the set $U(n)$. Is it because two consecutive numbers are always relatively prime?


What is the difference between a natural join and an inner join?

I am wondering how to differentiate all these different joins ...


I have lots of voice memos taking up a lot of space. There are too many to remove them manually. I have searched and cannot find a solution. Maybe there isn't one, but has anyone got a method of transferring a lot of voice memos in one go? Voice memos no longer show up in iTunes so  does not apply.

iOS seems to refuse to allow me to email "long" voice memos, and I'm unaware of any way to extract them from iTunes backups of my phone. How can I retrieve entire voice memos that aren't really short?


How could it possible to factorise $x^8-1$ in product of irreductibles in the rings $\mathbb{Z}/3\mathbb{Z}$?  Theorem : Let $A$ an integral domain and $I$ a proper ideal of $A$. If $f(x) \not \equiv a(x)b(x) (\mod I)$ for any polynomials $a(x)$, $b(x)$ $\in A[x]$ of degree $\in [1, \deg(f))$, then $f(x)$ is irreductible in $A[x]$  I think I have to use this theorem, but I am not certain. Is anyone could help me at this point?

How could it possible to factorize $x^8-1$ in product of irreducibles in the rings $(\mathbb{Z}/2\mathbb{Z})[x]$ and $(\mathbb{Z}/3\mathbb{Z})[x]$?  I'm having a hard time starting the problem. Could anyone help me at this point?


How do I make obj2 the same as obj1 but not affected by the deletion?  Currently the name: 42 entry will be deleted from both objects.  Is it because of hoisting - that is, the deletion occurs before obj2 is created?    var obj1 = {  'name': 'John',  'age': 42, }  var obj2 = obj1  delete obj1['name']  console.log(obj1) console.log(obj2)

What is the most efficient way to clone a JavaScript object? I've seen obj = eval(uneval(o)); being used, but . I've done things like obj = JSON.parse(JSON.stringify(o)); but question the efficiency.  I've also seen recursive copying functions with various flaws.  I'm surprised no canonical solution exists.


I am calculating the number of days between the 'from' and 'to' date. For example, if the from date is 13/04/2010 and the to date is 15/04/2010 the result should be  How do I get the result using JavaScript?

How do I get the number of days between two dates in JavaScript? For example, given two dates in input boxes:  <input id="first" value="1/1/2000"/> <input id="second" value="1/1/2001"/>  <script>   alert(datediff("day", first, second)); // what goes here? </script>


Hi Everyone and thanks in advance for the help. I'm having an issue with getting my Javascript date code to advance from the current date to tomorrow's date. I've searched here in previous posts but the answers don't seem to be working.  <SCRIPT LANGUAGE="JavaScript"> // Get today's current date. var now = new Date();  // Array list of days. var days = new Array('Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday');  // Array list of months. var months = new Array('January','February','March','April','May','June','July','August','September','October','November','December');  // Calculate the number of the current day in the week. var date = ((now.getDate()<10) ? "0" : "")+ now.getDate();  // Calculate four digit year. function fourdigits(number) {     return (number < 1000) ? number + 1900 : number;                             }  // Join it all together today =  days[now.getDay()] + ", " +      months[now.getMonth()] + " " +      date + ", " +      (fourdigits(now.getYear())) ; </script>   Where would the + 1 be inserted in order to make the date tomorrow's date?

How to add days to current Date using JavaScript. Does JavaScript have a built in function like .Net's AddDay?


I would like to monitor the directory using python. Whenever there is a new file the program will notify the user.  Current I am using a loop, which run os.listdir, to poll the directory regularly. However this is very inefficient. Is there any way that I could setup some software trigger (in Python) to enhance the efficiency?  Thanks in advance

I have a log file being written by another process which I want to watch for changes. Each time a change occurs I'd like to read the new data in to do some processing on it.  What's the best way to do this? I was hoping there'd be some sort of hook from the PyWin32 library. I've found the win32file.FindNextChangeNotification function but have no idea how to ask it to watch a specific file.  If anyone's done anything like this I'd be really grateful to hear how...  [Edit] I should have mentioned that I was after a solution that doesn't require polling.  [Edit] Curses! It seems this doesn't work over a mapped network drive. I'm guessing windows doesn't 'hear' any updates to the file the way it does on a local disk.


I want to parse a string like this - "The time is 12-jan-20 12:11:32.1112 AM"  I used this regex to group the timestamp = (?s)^.?(?:\s|^)?(?<time>(?<!\d)(?:0?\d[012]?)(?:-|:|\.)[0-5]\d(?:-|:|\.)[0-5]\d.*(?:a|A|p|P)(?:m|M))  Refer -   The group 'time' contains 12:11:32.1112 AM. But I don't want the millisecond value(.1112) in the group.  I want to group the string as 12:11:32 AM  Is it possible to exclude it while grouping with regex?

Is it possible to skip a couple of characters in a capture group in regular expressions? I am using .NET regexes but that shouldn't matter.  Basically, what I am looking for is:     [random text]AB-123[random text]   and I need to capture 'AB123', without the hyphen.  I know that AB is 2 or 3 uppercase characters and 123 is 2 or 3 digits, but that's not the hard part. The hard part (at least for me) is skipping the hyphen.  I guess I could capture both separately and then concatenate them in code, but I wish I had a more elegant, regex-only solution.  Any suggestions?


I have jobs installed in my system and it works indeed. However, when I typed   man jobs   and pressed enter, the terminal told me   No manual entry for jobs   Do you have the same problem? Or how can I solve it?

Why do some bash built-ins (such as dirs, pushd or help) don't have manual entries?


I wanted to install Ubuntu on my new laptop, but I don't want to replace my operating system (Windows 7) that I just purchased. When I start the downloader from a CD Burned image, it acts as though I am replacing my new OS, despite the fact I was told it would give me an option to install it as a program. Will it replace it, or I am just being stupid?

I would like to see a full how-to guide on how to install Ubuntu.


I had my finals for mg chemistry lecture. When I was starting my examination my professor went to my side and picked up a piece of paper then I realized it was the formula card that one of my classmate created.  Then after the exam my professor talked to me. First he was saying that I keep on looking at my seatmate but I defended that I it was just a glance because of the noise created by my seatmate and that because it distracted me. After that he show the card hand asked me to explain about it. I told him that I didn't see it and that it is not mine but he kept on saying that it would be impossible for me to not see it. I called for my classmate, who is the owner of the card, and she was asked if it was hers. She said that I must've fallen of her bag. But my professor keep on insisting that I tried to cheat with the use of that card.  I am so frustrated because if you would try to look at it on my view you cannot see the formula card. I swear that I really did not see it and I didn't even thought of cheating. I don't know what would I do to prove my innocence especially that I'm just a student and the staffs of our college would not believe me. Can you give an advice? And also it would not be the end of my studying right? I would be able to continue my studies even though of what happened?

So unfortunately during an exam, I had the misfortune of using an eraser (with cover) that was not mine and had a small amount of words inside it unknown to me. I did not know this was the case, as I don't have a habit of unraveling erasers or looking at them closely?  However, now I face the problem in trying to defend myself against the accusation of me cheating.  I'm specifically concerned on my university's blank statement of "possession of unauthorized materials during an exam" is considered academic dishonesty. Seems like student conduct has all the power in trying to prove academic dishonesty, despite none of my test containing any of what to me is  unreadable, small notes.


I can not access my 1 TB HDD in any system ubuntu or windows after I recently tried to backup my ubuntu system on the external HDD using inbuilt applications (Backups, Deja Dup) . Backup was taking place smoothly in the middle of that it stopped working and I force quit all operations and restarted my laptop but now the hard disk can not be accessed and making my laptop hang whenever trying to access it.  As the data is important to me I tried using Photorec running it on a live usb stick. I went through  tutorial step by step, want to mention, each step was taking more than half an hour sometimes a whole hour but as they said, to be patient I was following each step carefully, now at the recovery step most of the sectors are showing reading error and estimated time is 133895h54m25 and keeps on increasing. Right now it is     > Photorec 7.0 Data Recovery Utility, April 2015Christophe GRENIER <grenier@cgsecurity.org>http://www.cgsecurity.orgDisk /dev/sdd - 1000 GB / 931 GiB (RO) - Seagate BUP Slim BK   Partition            Start         End        Size in sectorsP unknown          0     0      1    953869      45    15   1953525167    Pass 0 - Reading sector     20631/1953525167, 0/10 headers found Elapsed time 1h27m30s -Estimated time to completion 132332h45m05 Error reading sector      21528 >   What should I do in this situation? thanks.

I've run across (personally or by proxy) a bunch of storage media that exhibited physical problems during their life. Hard disks, solid state drives and other flash storage media all fail after some time. The situation is worse with USB flash drives and flash cards because of the large amount of suppliers with inferior flash cell and flash controller quality.  How can I reliably detect if a storage drive suffers from physical damage?  Note that this question isn't about file system integrity (which can be checked with ).


If $a_1,a_2,a_3$ are the roots of the cubic $x^3+7x^2-8x +3,$ find the cubic polynomial whose roots are: $a_1^2,a_2^2,a_3^2$ and the polynomial whose roots are $\frac{1}{a_1}, \frac{1}{a_2}, \frac{1}{a_3}.$ Not really sure where to go. Hints appreciated.

I'm given $a_1, a_2, a_3$ as roots of the equation $x^3 + 7x^2 - 8x + 3$ and need to find the cubic polynomials with roots $a_1^2, a_2^2, a_3^3$ and $\frac{1}{a_1}, \frac{1}{a_2}, \frac{1}{a_3}$.  It's in a chapter about Galois Theory and is preceded by a problem about elementary symmetric polynomials.  I'm guessing I need to use elementary symmetric polynomials to solve for the two desired functions, but I really don't know where to start.  Hints would be much appreciated.


How to record songs while listening (from online source) on Android 4.4/Nexus 5.  I am not able to find any apps for this. All voice recorder apps seems to be supporting only background sound, and not the device sound output (in earphone).

I have some apps that I want to record the output sounds locally before outputting to speaker, Bluetooth or any other output. So I get clean unadulterated audio, before any audio output mods.  My devices are rooted, some have custom ROMs.   Is there a way to do this internally, without any programming/coding knowledge? Can this be accomplished? Preferably with out hooking to PC as that prevents local saving.   include steps.  include references      Please excuse lack of tags, limited on choices.


In my class, my teacher told us that, we should find the differences between "make" and "do".   I'm Vietnamese so I'm confused with this question! Can you help me?  And the similar between them is the meaning? Right?

When should I use do, and when should I use make?     I made supper.        I'm doing my homework now.        He made it easier.   Is it true that make implies creation?


I want to find the integral $$\int\frac{x}{2x-2}dx$$ This is just a simple question from my textbook. But there seems to be two ways of solving it. If I simplify it to: $$\int1+\frac{2}{2x-2}dx$$ I can then either just integrate that and end up with this: (which is the answer in my textbook) $$\frac{x+ln|2x-2|}{2}+C$$ Or I can simplify  $\frac{2}{2x-2}$ to $\frac{1}{x-1}$ and then integrate, ending up with: $$\frac{x+ln|x-1|}{2}+C$$ I'm not sure if you one of these methods is wrong. Or if I've made a mistake somewhere.

Question:  Is it possible to get multiple correct results when evaluating an indefinite integral?  If I use two different techniques to evaluate an integral, and I get two different answers, have I necessarily done something wrong?    Often, an indefinite integral can be evaluated using different techniques.  For example, an integrand might be simplified via partial fractions or other algebraic techniques before integration, or it might be amenable to a clever substitution.  These techniques give different results.  For example, looking over a few other questions on MSE:      From : evaluate $$ \int x(x^2+2)^4\,\mathrm{d}x. $$    Via the substitution $u = x^2+2$, this becomes $$ \int x(x^2+2)^4\,\mathrm{d}x       = \frac{1}{10}x^{10} + x^8 + 4x^6 + 8x^4 + 8x^2 + \frac{32}{5} + C.     $$ However, multiplying out the polynomial and integrating using the power rule gives $$ \int x(x^2+2)^4\,\mathrm{d}x       = \frac{1}{10}x^{10} + x^8 + 4x^6 + 8x^4 + 8x^2 + C    $$     From :  evaluate   $$ \int \frac{1-x}{(x+1)^2} \,\mathrm{d}x. $$    Simplifying the integrand using partial fractions then integrating gives $$ \int \frac{1-x}{(x+1)^2} \,\mathrm{d}x       = \frac{-2}{(x+1)} - \ln|x+1| + C.    $$ Via integration by parts, we get $$ \int \frac{1-x}{(x+1)^2} \,\mathrm{d}x       = \frac{x-1}{(x+1)} - \ln|x+1| + C.    $$     From : evaluate   $$ \int \frac {\tan(\pi x)\sec^2(\pi x)}2\,\mathrm{d}x. $$    Using the substitution $u = \sec(\pi x)$, this becomes $$ \int \frac {\tan(\pi x)\sec^2(\pi x)}2\,\mathrm{d}x       = \frac {\sec^2(\pi x)}{4\pi} + C.    $$ Using the substitution $u = \tan(\pi x)$, this becomes $$ \int \frac {\tan(\pi x)\sec^2(\pi x)}2\,\mathrm{d}x       = \frac {\tan^2(\pi x)}{4\pi} + C.    $$


I have some XML data, I'm trying to store it in a variable and extract everything within <tag1> tags. I've tried this but it returns no output: $xmlData = '<xml foo foo foo>   <header> foo </header>   <tag1>     <tag2> foo </tag2>   </tag1>   <tag1>     <tag2> foo </tag2>   </tag1> </xml>'  $pattern = "<tag1>(.*?)</tag1>" [regex]::Match($xmlData,$pattern).Groups[1].Value  The desired output, where the indentations have been retained:   <tag1>     <tag2> foo </tag2>   </tag1>   <tag1>     <tag2> foo </tag2>   </tag1>

For example, this regex  (.*)<FooBar>   will match:  abcde<FooBar>   But how do I get it to match across multiple lines?  abcde fghij<FooBar>


I am new to TeX world, and I use pdfLatex very often.  But sometimes pdfLatex do not work. So I begin to wonder what the difference between all these tex commands.   Please give me some guiding information about all these command to make me stay away from confusion.   I will appreciate every comment or answer.  Thanks.

I am confused about what TeX and its offspring (LaTeX, pdfTeX/pdfLaTeX, e-TeX, ConTeXt, LuaTeX, etc.) are.  Some, like LaTeX, seem like add ons to TeX (maybe a change to the eyes and mouth, but not stomach). Others, like pdfTeX, seem like changes to the underlying system (i.e., a change to the stomach).  Is there a good reference that explains the differences and the evolution?


Here in Stack Exchange network (probably mostly in meta discussions and in chat) we often discuss about tags.   I wonder which of these two forms is the correct one: "the tag (tag-name)" or "the (tag-name) tag". What I mean is which of these two sentences is correct? (Or are they both correct?)   This question should have the tag . This question should have the  tag.    Just by comparing what other people commonly use, it seems that that latter is more frequent. If I search in the posts on meta.SE, I get for these two possibilities:   2 results for , 2 results for , 6 results for ; 32 results for , 11 results for , 47 results for .   (I wanted to try at least some tags which I guessed appear quite frequently in posts.)

Sometime like this case I don't know if I can put the name before or after the label (movie in this sentence)...  The movie "Die Hard" or The "Die Hard" Movie? The variable "X" or The "X" variable?  Are they both correct? What is their difference? What is the application of each? My question is not about "the" (), but the order of the "movie" and "Die Hard"


Problem: When trying to purchase in-app items, google play selects the wrong google account and do not allow the user to correct it.  Scenario: I have two google accounts, one private and one business. The private account is the default in google play when buying and installing apps. Though when trying an in-app purchase, the business account is choosen and cannot be changed. In my case, this prohibits me in-app purchases.  Further notes: Uninstalling/reinstalling app to be sure the correct account is used in google play has no affect.  Haven't tried removing the business account and see how it affects the in-app purchases as I'm reluctant to do so. (Other way around would have been better:)  Question: Have you encountered this problem and found a way to resolve/work-around it?

What is the procedure to change email account which you want to use to make in-app purchase?  Take a look at the image.    Click to enlarge the image  I am using 2 Gmail accounts and only 1 has a credit card attached. The primary account has a credit card, the secondary does not. But my secondary account is always in the payment dialogue. The secondary account is also not the account used in Play Store app.   I found no way to change this email.


Using srand(time(NULL)) seems overly deterministic. For example, when I run std::cout << rand() % 9000 I get 4275. When I run it again, I get 4311. It's too based on time.

I need a 'good' way to initialize the pseudo-random number generator in C++. I've found  that states:     In order to generate random-like   numbers, srand is usually initialized   to some distinctive value, like those   related with the execution time. For   example, the value returned by the   function time (declared in header   ctime) is different each second, which   is distinctive enough for most   randoming needs.   Unixtime isn't distinctive enough for my application. What's a better way to initialize this? Bonus points if it's portable, but the code will primarily be running on Linux hosts.  I was thinking of doing some pid/unixtime math to get an int, or possibly reading data from /dev/urandom.  Thanks!  EDIT  Yes, I am actually starting my application multiple times a second and I've run into collisions.


I'm trying to make some processes to do one task and I use Runtime.getRuntime().exec and any process read some long number from one file then use xor operand and write in another file. Finally main process should read each long number in files has produced and xor all again. Here is my code but when I run it I get NullPointerException in line that include Subprocess[i].waitFor() == 0. Why? Thanks for any help. I know what is NullPointerException and I don't want to ask about it!      Process[] Subprocess;     Subprocess = new Process[processCount];     for (int i = 0; i < processCount; i++) {         try {             String[] command = {"java", "-cp", pathSubProcess, "SubProcess", p, String.valueOf(i), String.valueOf(processCount), String.valueOf(size)};             Subprocess[0] = Runtime.getRuntime().exec(command);          } catch (IOException e) {             System.out.println(e.getMessage());         }     }     /////////////////////////////////////////////////////////////////////////     long xor = 1;     for (int i = 0; i < processCount; i++) {         if(Subprocess[i].waitFor() == 0){             xor = xor ^  pp.readFiles(i);         }     }     xor = xor ^ 1;

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I have an ASUS x555l laptop with intel core i5-5200u, geforce 840m and 6gb of ram. I wanted to upgrade the ram so i did some research and found out that 4gb of ram is soldered to the motherboard and 2gb is in the second slot. as far as i know dual channel only works with ram sticks with the same size so it should be running in single channel but when i checked cpu-z and aida64 both show that the laptop is running in dual channel:  . how does this work and if it's really running in dual channel would it still work if i changed the 2gb one with a new 8gb stick?

I had 4 GB RAM installed, running in dual channel mode.  RAM: Corsair TWIN2X4096-6400C5DHX (CM2X2048-6400C5DHX) Motherboard: Gigabyte GA-EP45-UD3R  Channel 0: DIMM1, DIMM2 Channel 1: DIMM3, DIMM4  DIMM 1: 2 GB, CM2X2048-6400C5DHX DIMM 2: -- DIMM 3: 2 GB, CM2X2048-6400C5DHX DIMM 4: --   I added 2 GB more in DIMM 2. So now I have 6 GB in total.  So this is the current configuration:  DIMM 1: 2 GB, CM2X2048-6400C5DHX, channel 0 DIMM 2: 2 GB, CM2X2048-6400C5DHX, channel 0 DIMM 3: 2 GB, CM2X2048-6400C5DHX, channel 1 DIMM 4: --   But now when I boot up, BIOS reports as running in "Flex" mode.    Why is that? The module I added is of the same brand and part number as the other ones that were already installed. From what I have read on the web, the "flex" mode only appears if you mix and match different module sizes, or different brand and part numbers.  In fact, here is a quote from the motherboard manual about it:     When memory modules of different capacity and chips are installed, a   message which says memory is operating in Flex Memory Mode will appear   during the POST. Intel® Flex Memory Technology offers greater   flexibility to upgrade by allowing different memory sizes to be   populated and remain in Dual Channel mode/performance.   Here is a screenshot of a RAM report.    How do I tell if at least the original two RAM modules are running in dual channel? What do I look for?  I notice that the module in slot 2 has a week/year parameter. While the original two do not. I don't think the date is accurate. But could this indicate that they are not same modules, internally? Like different revisions maybe?  Why are there two different JEDEC frequencies? One is at 270 MHz and the other is at 400 MHz, why is that?  This is what the DIMM slots look like:    Similar color means disimilar channel, and disimilar color means similar channel (in lack of a better way of expressing this idea). So yellow and yellow means channel 0 and 1, which makes up a dual channel. Similarly, red and red means channel 0 and 1. Colors are not an indication of channel (same color does not mean same channel), but a way to help install memory in dual channel mode. (Then you add the third wheel to the mix, like I did, and you're in this weird "flex" mode.)


While perusing through the many many questions about Harry Potter here, I stumbled upon  one that says Slytherin was not the first parselmouth and in fact a man named Herpo the Foul predates him. It also says in one of the answers that Parselmouth is something that is passed on through blood and can't really learned. Would this mean that Slytherin is a descendant of Herpo? Or does Slytherin's lineage lie elsewhere?

From what I can tell it is an inherited skill from wizard to wizard. According to this question:  Herpo the Foul seems to be the first or one of the first who were able to speak Parseltongue.  And from what I have researched, he was an Ancient Greek wizard and there is nothing of significance if he was related to Salazar Slytherin.  So my question is, how does Salazar Slytherin speak parseltongue? (which could possibly be answered by if he was actually related to Herpo the Foul)


I am currently working through Optics by Eugene Hecht. When two waves intersect together, Hecht shows that the total irradiance $I$ is $$I=I_1+I_2+\sqrt{I_1I_2}\cos{(\delta/2)}$$ where $I_1$ and $I_2$ is the irradiance of each separate wave and $\delta$ is the phase difference between the two waves. When we consider the irradiance of the two waves to be the same and we have no phase difference , we see that the total irradiance is $$I=4I_0$$ Why does this not contradict the conservation of energy. When the two waves are separate we have a total of $I_0+I_0=2I_0$ irradiance in the room. So how do we double that?

I have a problem with energy conservation in case of interfering waves.  Imagine two harmonic waves with amplitudes $A$. They both carry energy that is proportional to $A^2$, so the total energy is proportional to $2A^2$. When they interfere, the amplitude raises to $2A$, so energy is now proportional to $4A^2$ and bigger than before.  The equivalent question is what happens to the energy with the superposition of two waves that interfere destructively.  Also, if someone could comment on the statement about this problem in my physics book (Bykow, Butikow, Kondratiew):      The sources of the waves work with increased power during the interference because they feel the wave from the other source.


Suppose I have taken 5 measurements, each with an associated error, let's call these values $\eta_i\pm\sigma_i$, where $i$ is an integer from 1 to 5.  I would like to find the mean and standard deviation of these quantities, $\bar{\eta}\pm\bar{\sigma}$.  The mean can be calculated simply:  $\bar{\eta}=\sum_{i=1}^{5}\eta_i$.  How is the standard deviation $\bar{\sigma}$ calculated, including the contribution from the deviation of $\eta_i$ about $\bar{\eta}$, and also the contribution from the errors $\sigma_i$?  EDIT To give some more context, the $\eta_i$ are a function of the number of counts $N$ of a Poisson distributed variable. Due to the high number of counts, $\sigma_i$ is a function of $\sqrt{N}$, which is the standard deviation of the count number.  Thus, I definitely know the errors $\sigma_i$. However, I would like to combine my repeated measurements to find a mean and deviation.  EDIT#2 My reading into the topic thus far has led me to this page on propagating errors ().  The example formulas tab has an example for the function $f=aA+bB$, which should be applicable in my case where I would like to find the mean. For my purposes (finding the mean) $a=1, b=1$. Using this entry in the table, $\sigma_f=\sqrt{\sigma_A^2+\sigma_B^2+2\sigma_{AB}}$, where $\sigma_{AB}$ is the covariance.  If I were to apply this reasoning to my problem, I should get:   $\bar{\sigma}=\sqrt{\sum_{i=1}^5\sigma_i^2 + 2cov}$, where $cov$ is the covariance.  I am rather unfamiliar with the covariance, but I think that in my example, it is equal to the variance of my 5 different $\eta_i$.  In other words, $cov=\frac{\sum_{i=1}^5(\eta_i-\bar{\eta})^2}{5}$  My question, is this interpretation right for the propagation of my errors, and if not, where has my reasoning gone wrong?

I have a large set of data points of the form (mean, stdev). I wish to reduce this to a single (better) mean, and a (hopefully) smaller standard deviation.  Clearly I could simply compute $\frac{\sum data_{mean}}{N}$, however this does not take in to account the fact that some of the data points are significantly more accurate than others.  To put it simply, I wish to preform a weighted average of these data points, but do not know what the weighting function should be in terms of the standard deviation.


I have a 105 mbps internet connection , that gives me 96 mbps speed  shown on speed test. I get this speed when I connect to a wired ethernet connection , either directly to the modem or through a router . But the problem occurs when I connect wirelessly to the wifi network of the same router. I get only 20mbps. It is linksys e2500 router , that allows simultaneous dual bands . i have tried connecting on 5Ghz network and 2.4ghz , tried all possible combinations , mixed mode , n -only , g-only etc , nothing gives me more than 20 mbps on the wifi network. My laptop does not support 5ghz network but it support the n-standard on the 2.4 ghz. But I do have other devices in the house that support the supposedly empty 5ghz channel . I have tried everything and I never get more than 20mbps on wifi through the same router than gives 95 mbps on wired ethernet.  What can I try ?

When I plug my laptop via LAN cable and check speed on speedtest.net I have over 32 Mb/sec. When I unplug the cable and connect to the same router I have less than 15 Mb/sec. I tried to change channels already but this didn't help. I'm sitting just near the router.   What can it be? The router is a Dlink 400.


So when I solve $\sqrt{5x+4}=x-2$, I end up with $x(x-9)=0$. Yet only when $x=9$ is the original inequality satisfied. Can somebody give me some details on what exactly goes wrong here?

I'm currently learning about radicals and simplifying them, and I came across this problem on the internet and tried to solve it:  $$\sqrt{x+5} = x - 1$$  So I used this logic:  $$ \begin{align} \sqrt{x+5} &= x - 1 \\ x + 5 &= (x-1)^2 \\ x + 5 &= (x-1)(x-1) \\ x + 5 &= x^2 - 2x + 1 \\ 0 &= x^2 - 3x - 4 \\ 0 &= (x-4)(x+1) \\ \end{align} $$  Therefore, $x = -1$ and $x = 4$ satisfy the equation $0 = (x-4)(x+1)$.  But then I tried to plug them in the original problem $\sqrt{x+5}=x-1$:  $$ \begin{align} \sqrt{4 + 5} &= 4 - 1 \\ \sqrt{9} &= 3 \\ 3 &= 3 \end{align} $$  So using 4 works as expected, but when using $-1$:  $$ \begin{align} \sqrt{-1 + 5} &= -1 - 1 \\ \sqrt{4} &= -2 \\ 2 &\ne -2 \end{align} $$  At what stage am I going wrong?  And according the , the solution is $x = 4$.


I realized that Quantum Random Access Memory (qRAM) was proposed to make quantum computers more similar to classical one. Currently quantum computers have very constrained memory, given only quantum registers on quantum processors can be used for an algorithm to run. It is true that e.g. Qiskit language allows to use RAM or HDD of classical computer, however, resulting algorithms are hybrid quantum-classical.  I found some proposals how to implement qRAM, e.g. .  But my understanding is that the device is highly experimental nowadays.  So my questions are those:   Does anybody know about progress in this field? Some links to articles of state-of-art implementation of qRAM will be highly appreciated. What about IBM Q? Do we have an opportunity to use qRAM on IBM Q computer in foreseeable future (i.e. few years)?

Presently, how much information can a quantum computer store, in how many qubits? What restrictions are there and how does it vary across realizations (efficiency of data storage, ease of reading and writing, etc)?


void test(int* x, int y) {     for (int i = 0, j = 0; i < y; ++i) {         if (i % 2 == 0) {             x[j] = i;             ++j;         }     } }  int maxRange = 10; int *a; test(a, maxRange); // a = { 0, 2, 4, 6, 8, 10 }  How can I find length of a? The length is 6. I tried sizeof(a) and sizeof(a) / sizeof(a[0]). Thanks for any help!

How do I determine the size of my array in C?   That is, the number of elements the array can hold?


Is it possible to save list as a template using CSOM?  We need to create a list template every weekend in SharePoint Online. I thought of using task scheduler with a console application but could not find a way to save a list as a template.   For full trust code we have saveListAsTemplate method, but I couldn't find any in CSOM.  What are my options?

For creating a list template programmatically by using server object, I'm using the SaveAsTemplate() function.  SPSecurity.RunWithElevatedPrivileges(delegate {   using (SPSite oSPsite = new SPSite(strSiteURL))   {     oSPsite.AllowUnsafeUpdates = true;     using (SPWeb oSPWeb = oSPsite.OpenWeb())     {       oSPWeb.AllowUnsafeUpdates = true;        SPList list = oSPWeb.Lists[strListName];       string bkpTemplateName = "bkp" + strListName + ".stp";       list.SaveAsTemplate(bkpTemplateName, bkpTemplateName.Replace(".stp",""), "Description", true);        list.Update();       oSPWeb.AllowUnsafeUpdates = false;     }     oSPsite.AllowUnsafeUpdates = false;   } });   But, is there a way to do the same by using CSOM?


Say I have a project folder containing a number of header and source files for c++; How would I count the total number of lines of all of these?

if I want to count the lines of code, the trivial thing is  cat *.c *.h | wc -l  But what if I have several subdirectories?


I'm currently on Ubuntu 18.10 and tried to upgrade to 19.04 via   $ sudo do-release-upgrade -d Checking for a new Ubuntu release Get:1 Upgrade tool [1.214 kB]                                                                                Err Upgrade tool signature                                                                                404  Not Found [IP: 91.189.91.23 80]                                                                                Fetched 1.214 kB in 0s (0 B/s)                                                                                WARNING:root:file 'disco-updates.tar.gz.gpg' missing Failed to fetch Fetching the upgrade failed. There may be a network problem.   Network connection is fine, I don't have any outages. I'm not too experienced with using Ubuntu yet, so instead of tweaking files I thought I'd ask first.  Edit: I don't know why I though I should use -d, but leaving that out upgrading works.

The update from Trusty to Xenial is officially available via the software updater. After updating all packages, upgrading through the software updater yields:  Fetching the upgrade failed. There may be a network problem.   Doing a sudo do-release-upgrade yields:      Checking for a new Ubuntu release Err Upgrade tool signature                                                        403  Sorry, not allowed to fetch that type of file: xenial.tar.gz.gpg         Err Upgrade tool                                                                  403  Sorry, not allowed to fetch that type of file: xenial.tar.gz             Fetched 0 B in 0s (0 B/s)                                                       WARNING:root:file 'xenial.tar.gz.gpg' missing Failed to fetch Fetching the upgrade failed. There may be a network problem.


I use below code,  \listofrequirement  \listoftables   but the output is like this, the size of  "list of tables" is too big, how to make it smaller like the size of "list of requirements"?

Below picture shows my table of contents  The title size (the word, Contents) is very big, maybe Huge. I never set it as Huge and I searched the whole LaTeX file, there is no the word "huge" at all.  And the number is start with 0, for example "0.1 Introduction", not the normal "1 Introduction"  Below is the only code related with ToC  \usepackage[subfigure]{tocloft} . . . \setcounter{tocdepth}{2} \tableofcontents   What problem it can be?  PS: I tried to use \usepackage{xpatch}, but this one does not work   I use report   \documentclass[a4paper,leqno,twoside]{report}   Thanks everyone! I changed report to article, the problem is gone!


Early this year, I had a surgery-related study in rats and today I just found out my first authorship got turned into the second authorship in the final manuscript my PI planned to submit.   For the study which was my original idea, I spent a tremendous amount of time in conceptualizing the study, created the protocol and design for the stud (second and third authors also involved in this but not as much as I did), carried out all the animal surgeries and analyzed a part of the data independently (for this study, there were only two results we could get), and wrote the part of manuscripts.   The divided tasks between the first and second author for this project was I did all of the above mentionings, while the second author collected, collaborated with two other pathologists who are going to be the co-authors and wrote the discussion and conclusion section.   But all of a sudden, I was just informed today my PI is making the second author the first author because she spent so much time in collaborating with those pathologists and revising the manuscripts with her (they are very close to each other because the second author works full time but I worked the only parttime).   It was so ridiculous because it was our agreement before that she was in charge of the pathology section for the paper with other pathologist and I was in charge of other results. For the whole revision process, both the third author and I haven't been informed by any mean. And I always thought the manuscript was all done except the pathology part.   I brought up the concern to the second author and she told me she deserved the first because "I spent as much time as possible with PI in rewriting the discussion and manuscript" (without letting me know) and collaborate with other authors to put their input into the results which I don't even really need this part to make it published. (Moreover, it was my idea to work with the pathologists and I was the one who assigned her the tasks she needs to do with them).   I am so pissed off now and I would like some advice about my situation. I understand this second author spent a lot of time in revising the manuscript (she is good at writing so we agreed before she would write the discussion and edit the paper) but this was done without informing both first and third authors. And it was all because of me to make the project possible when none of the people including the PI likes the project early this year. I was the one spent every weekend and night time alone (until 10 or 11 pm can you guys image?) to carry out all the trails. I was also the one who analyzed the most important part of the data and gave all the inputs the second author needs to form the paragraphs. Now, what she did was just to put others' opinion (pathologists) into the paper, and remake the figures and table I made, so she and the PI wants to make her as the first author. Please help that this lab is so sneaky and horrible. And the similar sneaky revision happened before already to my work (Fountly, I kept my first authorship that time). I would like to take whatever I can to defend my right as I am done in the lab and I don't care if I will continue research in this field or to make the work unpublished.   *Note: Also, the PI and she added another person to the authorship who did nothing but for a "gift" because she is the new hire. but the other volunteer we had in the lab who actually contributed got nothing out of it. I feel so bad for her now too.

I am currently submitting a paper for Nature Structural & Molecular Biology. I worked on this project for the last four years and was the only one working on this project. I had everything going very well. In order to get the crystallization, I gave the plasmid construct to another laboratory which has expertise in crystallization. Fortunately, they got the crystals. After the crystallization got successful, one researcher (say, A) from their lab came to my lab and my professor told me to teach him all the methods. I happily agreed to do so. After A went back to his lab, I got the draft of the paper from my professor, where, my name appeared as first co-author! I almost fainted. There were 20 figures in the paper. 13 were contributed by me, 4 by A and rest by 2 other people. The paper was mostly about my work. But in the contribution section, my prof and the prof of A  mentioned that I and A had equal contribution. In fact it is mentioned that A was solely contributor of crystals and he equally contributed in all other results. I discussed this issue with my prof, but he tells that he is getting pressure from A's prof to make A the first author. And my prof does not want to estrange relationship with A's prof. I am heart-broken and I don't know what to do. Please suggest me what to do. Edit 2021: It has been quite some time since I posted this question. I accepted the authorship as recommended by my advisor. Now I feel mature and realize that maintaining a cordial relationship with one's advisor and colleagues is more important than anything else. If one is capable enough, s/he will get more opportunities to prove their worth.


I just started a new job and inherited someone else's computer. Earlier this week I got notifications saying that my C: drive was almost full, so I cleaned a few things out. In the process I discovered that  226 of 232GB are being used on the drive! Obviously I want to figure out what the source of most of this is and see what can be cleaned out.  The best way I know of to determine how large a folder is in Windows is to right click, Properties, and look at the size. The problem is that the sum of the folders in the C: drive is only 44G, leaving 180G unaccounted for. Now, I know that this will skip over folders I don't have permission to view, so I tried running Explorer as administrator, but no change.  What am I doing wrong? How can I determine what is using up all of this disk space?  PS, I did see , but I would really prefer a solution that doesn't require installing new software. We have restrictions and requirements that make it a pain to install anything.

How can I visualize which folders and files are taking up all of the space on my hard drive?  I'm getting some conflicting reports on the size of hard drive contents. Namely what is and isn't there and what folders are actually using the space.   I need to know which of the files or folders the culprits behind all this hidden bloat. Also there should be a print option to get it on paper.


I am facing some problems trying to access a context variable in my django views in my html javascript. I would like to access 'unclean' context which is a list and USE IT AS A LIST in my html script tag. Any help is appreciated. Thank you. Below are some of my code:  views.py  context = {    'unclean' : unclean        }

When I render a page using the Django template renderer, I can pass in a dictionary variable containing various values to manipulate them in the page using {{ myVar }}.  Is there a way to access the same variable in Javascript (perhaps using the DOM, I don't know how Django makes the variables accessible)? I want to be able to lookup details using an AJAX lookup based on the values contained in the variables passed in.


I would like to use the sum sign in an conditional expression. There is no error message but the Fz is supposed to be under the sum sign but instead its a subscript. Can someone help me solving my problem?  \begin{equation}   X = \left\{   \begin{array}{ll}   q_{B} = \sum_{Fz}\left(WT_{Fz}  & , \textnormal{ if } q_{B} > 1800 * N_{FS} \\   q_{S} = \sum_{Fz}\left(WT_{Fz}  & , \textnormal{ if } q_{B} \leq 1800 * N_{FS}\\   \end{array}   \right.   \end{equation}

I'm very familiar with how symbols display differently in inline mode (with $ ... $) vs. how display math shows them (with \[ ... \] or $$ ... $$).  Two examples would be with limits  $\lim_{n\rightarrow \infty}f(x)$   vs.  \[ \lim_{n\rightarrow \infty}f(x) \]   and with sums  $\sum_{n=1}^{x} n^2$   vs.  \[ \sum_{n=1}^{x} n^2 \]   My Question is:     How do you display these things in inline mode (with all the nice inline formatting) as if they were in display mode ?   The inverse -- how to display things in display mode as if they were in inline mode -- is also of interest.


What is the difference when I have for example,   int var1, *ptr; ptr = &var1; // the pointer ptr copies the address of var1, hence ptr points to var1?  int var1, *ptr; ptr = var1; // ptr points to var1, but does not have the address of var1, so can not change the value of address var1?   int *var1, *ptr; *ptr = *var1; // copy value of var1 into the location pointed to by ptr?   are my comments correct ?

I know references are syntactic sugar, so code is easier to read and write. But what is the difference between a pointer variable and a reference variable?


My university is testing an intro Machine Learning (ML) course for us undergrads, and having been interested in ML since the beginning to understand what it was, I jumped at the chance to take it. But being someone who has not been back in school for a long time and much busier than I was in my first years long ago, I am finding that I need more info and examples than the class in its current form has. I am struggling to figure out what the attached question is asking. I am searching online for help with this particular topic, but I am also finding that everyone seems to have their own way of phrasing similar questions in such a way that I am finding it hard to link the info.  My understanding from stats way back when is that p(x|ω1) p ( x | ω 1 )  is stating the probability of x x  given ω1 ω 1 for 0≤x≤2 0 ≤ x ≤ 2  and zero other wise. Same obviously if given ω2 ω 2 . If I understand, the priors are the probability of ω1 ω 1  and ω2 ω 2  which are somehow obtained. And honestly that is as far as I am really comprehending. I am not sure what (a) and (b) are truly asking for or how to get them. If anyone is able to help me with some pointed info on the topic it would be greatly appreciated.

My university is testing an intro Machine Learning (ML) course for us undergrads, and having been interested in ML since the beginning to understand what it was, I jumped at the chance to take it. But being someone who has not been back in school for a long time and much busier than I was in my first years long ago, I am finding that I need more info and examples than the class in its current form has.  I am struggling to figure out what the attached question is asking. I am searching online for help with this particular topic, but I am also finding that everyone seems to have their own way of phrasing similar questions in such a way that I am finding it hard to link the info.   My understanding from stats way back when is that $p(x|\omega_1)$ is stating the probability of $x$ given $\omega_1$ for $0\le x \le 2$ and zero other wise. Same obviously if given $\omega_2$. If I understand, the priors are the probability of $\omega_1$ and $\omega_2$ which are somehow obtained. And honestly that is as far as I am really comprehending. I am not sure what (a) and (b) are truly asking for or how to get them. If anyone is able to help me with some pointed info on the topic it would be greatly appreciated.


My site is online for more than 3 months now but I don't have Alexa rank. I don't understand why.  Could anyone explain this to me?

When I check Alexa rankings for my site it says that one site is linking to my site.   Is it only showing back links? If it is then why are other website traffic checking tools like Google showing different different back links?


As I understand it, each nucleus of a cell contains multiple chromosomes. Each chromosome has multiple DNAs. Each DNA contains some specific gene sequences. That sequence is called Genome.  My question, do all chromosomes in cells in a human body contain same types of genomes (i.e. gene sequences)?

So I am new to biology and I have been reading, and searching the web, but I couldn't understand the whole framework of a cell. So as I understood:    A DNA, is a double chain of Nucleotides (A,T,G,C and a sugar) and a phosphate residue. Some parts of a DNA code a gene and some do not, exons and introns accordingly. As I understand it these the sequences of exons hold genes and the whole sequence is called genome. Now I read in the book Introduction to Computational Molecular Biology by J. C. Setubal and J. Meidanis. that I cite Each cell of an organism has a few very long DNA molecules. Each such molecule is called a chromosome. So each X shaped thing called a chromosome holds one DNA molecule?   Or is each "hand" of the chromosome one complete double helix of DNA so we have 23 pairs of such chromosomes? or is it that each we 23 pairs Xs?   Shouldn't we have just one uniquely identifiable DNA sequence? I am asking this, because I have also read that each chromosome encodes a different part of one's genome. Does this mean we have several DNA sequences?   This is really bothering me, since I can't figure out the correct structure of a cell.   EDIT: Now if each chromosome contains a pair of DNA helices. We have 46 chromosomes so overall within the cell there are 92 DNA sequences? All of which are the same? Or are they different? If they are different how do they code for different aspects of one's genome?


For my thesis I started to use LaTeX as a text editor. I am now in the process of figuring out basically everything. But the coding is not completely unknown to me. However, I get stuck on small point. I want to refer to articles that I used, by showing their surnames follwed by a comma and then the the year of publication.  Currently my code of the main file looks like this:  \usepackage[utf8]{inputenc} \usepackage{graphicx} \graphicspath{ {C:\Users\beren\Documents\Master SCM\Thesis\Images} } \usepackage[a4paper, width=150mm, top=1mm, bindingoffset=1mm]{geometry} \usepackage{fancyhdr} \pagestyle{fancy} \fancyhf{} \fancyfoot{} \fancyfoot[LE,RO]{\thepage} \fancyfoot[LO,CE]{Chapter \thechapter} \fancyfoot[CO,RE]{My Name} \renewcommand{\headrulewidth}{0.4pt} \renewcommand{\footrulewidth}{0.4pt} \usepackage[backend=bibtex, style=authoryear, sorting=nyt]{biblatex} \renewcommand*{\nameyeardelim}{\addcomma\space}  \addbibresource{references.bib}   My code in references.bib would look like this for example:  @book{NSP,     author        = {A. Doe, W. Schoenmakers},     title         = {North Sea Ports in Transition: Changing Tides},     year          = {1998},     chapter = {2 Port of Rotterdam: From Landlord to Mainport} }   As you can see the book includes multiple authors, currently only Doe is showing up in the inline reference, but this should also be Schoenmakers. Could someone explain what I do wrong in the coding?  as well \parencite[33]{NSP}     I prefer to use APA style referencing. I know that a package exists for this as well, but I am using Bibtex which should also do the job.   One question adding to that for probably in the future, how would this work if I want to refer to the same source (consisting of multiple (3+) authors) again, but then using et al. instead?

I use  to store all articles I need and bibtex4word add-on (in MS Word) to maintain the reference list. So, I would like to know how to properly fill the "author" field in Jabref with multiple authors to appear them correct in the reference list.  For example, I've got the article with several authors:      E. Orti, J.L. Bredas, C. Clarisse   And I would like them to appear in this manner. But instead I get this:     C. C. E. Orti, J. L. Bredas


In Problems in Mathematical Analysis, Volume 2 by Kaczor and Nowak, Problem 2.3.34 is stated as follow.   Find this limit using L`Hôpital rule  $$\lim\limits_{x\to\infty}x((1+\frac{1}{x})^x-e).$$  I have tried by using L'Hospital rule five times but have no result.  I can compute this limit by using Taylor expansion.

Evaluate the limit: $$\mathop {\lim }\limits_{x \to \infty } x\left( {{{\left( {1 + {1 \over x}} \right)}^x} - e} \right)$$  My attempts didn't yield a result. I'd be glad for a guidance. Thanks!


I am having issues with proving the second step, and have been told that it would be best to approach this question by induction. I have manages to get this far:  $$\left(\int_{a}^b g(x)f(x)=\frac{(-1)^{k}}{c^{k}}\int_{a}^b g(x)f^{(k)}(x)\right)\times\frac{-1}{c}$$ $$\frac{-1}{c}\int_{a}^b g(x)f(x)=\frac{(-1)^{k+1}}{c^{k+1}}\int_{a}^b g(x)f^{(k)}(x)$$ $$-\int_{a}^b g(x)f(x)=\frac{c(-1)^{k+1}}{c^{k+1}}\int_{a}^b g(x)f^{(k)}(x)$$ $$-\int_{a}^b g(x)f(x)=\frac{(-1)^{k+1}}{c^{k+1}}\int_{a}^b cg(x)f^{(k)}(x)$$ $$-\int_{a}^b g(x)f(x)=\frac{(-1)^{k+1}}{c^{k+1}}\int_{a}^b g'(x)f^{(k)}(x)$$  From here I have no idea how to produce $f^{(k+1)}(x)$ inside the integral, or whether this was the right way to approach solving this problem. Any pointers with how to proceed would be awesome!  Cheers

I have shown the first part by using integration by parts, but at am at a lost as to how I will be able to employ that result to be able to prove the second part. Any help on how to proceed is seriously appreciated!  Edit: So I have looked at the induction process but am still confused. This is where I am at right now:  $$\left(\int_{a}^b g(x)f(x)=\frac{(-1)^{k}}{c^{k}}\int_{a}^b g(x)f^{(k)}(x)\right)\times\frac{-1}{c}$$ $$\frac{-1}{c}\int_{a}^b g(x)f(x)=\frac{(-1)^{k+1}}{c^{k+1}}\int_{a}^b g(x)f^{(k)}(x)$$ $$-\int_{a}^b g(x)f(x)=\frac{c(-1)^{k+1}}{c^{k+1}}\int_{a}^b g(x)f^{(k)}(x)$$ $$-\int_{a}^b g(x)f(x)=\frac{(-1)^{k+1}}{c^{k+1}}\int_{a}^b cg(x)f^{(k)}(x)$$ $$-\int_{a}^b g(x)f(x)=\frac{(-1)^{k+1}}{c^{k+1}}\int_{a}^b g'(x)f^{(k)}(x)$$  From here I have no idea how to produce $f^{(k+1)}(x)$ inside the integral, or whether this was the right way to approach solving this problem. Any pointers with how to proceed would be awesome!


I would like to find out the month and year I signed up for my current Gmail account.

Well, it's a long time I'm using my Gmail account. Today, I had a talk with my friends about the date we created our Gmail accounts and we all had some guesses about it. Is there any option in Gmail info/settings where I can see the date I created my account?


I have a list containing 200 items (List A)  In my new list (List B) I want to include a lookup that will pull through the title from List A. OOTB lookup columns are drop downs and as List A continues to grow this isn't going to be fit for purpose so what I want to do have a single line of text that will work like googles search bar and once the user begins typing the title of an Item in List A it will show suggestions.  Does anyone know a way to achieve this without complex coding

Can we make a SharePoint field which is a lookup drop down box on the editform.aspx. have the functionality so that user can type in and select from the options based on the values of the types?


When looking at a PDF document I often want to zoom-out to scroll quickly to its contents and get an overview.  However, when I zoom-out past a certain threshold (it seems to differ per PDF) Safari thinks I want to see the tab overview:    I have never found a use for this function, so it only causes annoyance.  Can I turn this tab overview off somehow? A solution that uncouples the pinch-to-zoom gesture from the functionality would also work.  I'm on Mountain Lion 10.8.5 with Safari 6.1.3.

Too often, when I try to move my cursor and click, or try to drag something or select text, and my two fingers end up on the trackpad at the same time, all my open tabs shrink into this view:    This is extremely disruptive as it makes me lose my focus and then I have to locate the page I was currently on, click it and then resume working.  I can't tell what this specific feature in Safari is called (I want to still be able to pinch to zoom in and out of a page), and couldn't find info anywhere on how to completely disable it.  Can I disable this? (or I can use another browser, obviously...)


Hi i have some problem in the static resources using in jqueryui in visual force, dowmloaded jquery-ui-1.10.3.custom.zip , and stored in static resources page , but unfortunely the ui is not working , if anyone guide me how to use static resources   ganesz

Ill implement the some UI but its not working in the visualpage , can u know how implement jquery ui in viusalpage ,  Kindly tell the procedure ,     Im using this url its not working ,,,,,


In the traditional "pin" approach to maps, the pin essentially "points" to the actual latitude/longitude. Alternatively, you could have a symmetric (e.g. circular) icon that is essentially centred on the latitude/longitude. Have there been any usability studies or guides for when to use which type?  Example map pin:     Example symmetric marker:     My question is whether to have markers "point" to their exact location (i.e. using a "pin"), or whether to centre them on top of that exact location (e.g. using a circular icon). In neither case am I referring to clustering, as I will not be clustering markers.

I'm building a very small app that allows my users to post content to a map.  The home screen of the app contains a map with all of the posts (as seen below).  PROBLEMS  01 - if a user posts a post from the same area, two pins will be on top of each other so you won't be able to access one of them  02 - if a lot of content is posted it will be hard to click on each pin  03 - when you zoom all the way out, there will be too many pins  Can anyone recommend trying anything else please?


So I have a timeline with events that are very close to eachother, to avoid them overlapping, I would like to write events under and above the timeline in alternance. It seems that by default, events are always written under the timeline... Can someone help me with this?

The package  allows to draw a timeline with a reasonable degree of customization, without the need to draw it by yourself using tikz or similar tools.  In my opinion, is the most promising tool to draw timelines in a LaTeX document.    But it has a limitation. While the command \chronoevent accepts a date in dd/mm/yyyy format, the command \chronoperiode does not (only integers are accepted).  In this way, time periods cannot start on specific dates, and time periods shorter than one year cannot be drawn in the timeline.  Is there a way to overcome this limitation?


I've upgraded to 14.04 LTS, and now my volume up and down keys no longer work.  The mute button still works, bizarrely. The Media buttons (prev track, play/pause and next track) have also stopped working.  I have a previous generation Lenovo ThinkPad X1 Carbon i.e. the one without the 'soft function keys', so this is not a softkey issue.  Worked previously with Ubuntu 13.10. I am using an up to date install.  uname output: Linux 3.13.0-34-generic x86_64 GNU/Linux  I've checked the system settings->keyboard->shortcuts->sound and media and they register the up and down volume keys just fine. If I change the keys to be (say) ctrl- and ctrl+, then I can alter the volume, but when I change them back to 'Audio lower volume' and 'Audio raise volume' by using the keys, they no longer change the colume or activate the top-right corner 'control flash' the same way that mute or brightness controls do.  I'm at a loss. There's obviously nothing wrong with the keys, but somewhere in the OS the keypresses are being diverted or dropped and they don't make it through to applications as events...

When using the volume buttons (+, -, mute) there is no reaction, neither on laptop keyboard nor on USB keyboard. No popup, no volume change, and no sound indication.  Volume control with the mouse works fine.  The buttons are working and get recognized:  Checked with keyboard system settings tool: they get recognized by the tool both from the laptop directly as well as from my USB keyboard.  Who can help?