is there really some difference between if and whether? I've had a doubt about when I use if and whether. I saw an phrase using whether and now I'm thinking when really use it.  The phrase:   I don't know "whether" it was the burden of having to raise a large family, or his natural confidence in dealing with people, but my dad became an immediate success in his newfound profession.  Can I replace whether for if? However,  when I use whether?
"Whether" Vs. "If" Could someone please help me with these sentences? I need to know  Which one doesn’t sound natural? Which one is formal and which one is not?   A - I don’t know whether this word fits in the sentence. B - I don’t know if this word fits in the sentence.   C - I don’t know whether or not this word fits in the sentence. D - I don’t know if or not this word fits in the sentence.   E - I don’t know whether this word fits in the sentence or not. F - I don’t know if this word fits in the sentence or not.  For me only D doesn't work and sounds not idiomatic. Meanwhile for me all of these sentences can be used in both written and spoken languages. Do you confirm me?
My PDO Statement doesn't work Efficiently mix encryption and rsync on an external drive? I have a strange issue with Windows 10  When I open .nef files they load fine. However after a second or two the contrast changes noticeably. I tried Windows 10 Photos and Picasa Image Viewer.   What am I trying to accomplish? I just want to open files quickly to check for focus and composition before importing into Lightroom  Lightroom does not have this issue   Here is the example opening with Windows 10 Photos    And here is after a second when it 'fully' loads    Picasa Photo Viewer after it loads a bit. It initially opens fine but then it goes all purple What ingredients can I add to no-knead bread to extend its life? Is there anything I can add to a standard no-knead bread recipe to allow the bread to stay softer for longer? Bread baked the night before, while still edible, is not as pliable the next midday.  I currently use bread flour, yeast, salt and water but was thinking of adding milk, butter or eggs. If there is a single food additive I can add I would consider this, but I don't want to adulterate the recipe too much. Are comments discouraged in a BibTeX file? biber complains about "junk" in what should be seen rather as commented-out lines in a BibTeX file.  I was wondering if comments are discouraged in BibTeX at all.  \documentclass {article}  \usepackage {filecontents}  \begin {filecontents} {ref.bib}  @book {book1,  author={author 1},  title={title 1}}   book {book2,  author={author 2},  title={title 2}}   @book {book3,  author={author 3},  title={title 3}} \end{filecontents}  \usepackage [backend=biber] {biblatex} \addbibresource {ref.bib}  \begin {document}   \nocite{*}  \printbibliography \end {document}   Here is biber's output:  INFO - This is Biber 2.1 INFO - Logfile is 'mwe.blg' INFO - Reading 'mwe.bcf' INFO - Using all citekeys in bib section 0 INFO - Processing section 0 INFO - Looking for bibtex format file 'ref.bib' for section 0 INFO - Decoding LaTeX character macros into UTF-8 INFO - Found BibTeX data source 'ref.bib' WARN - BibTeX subsystem: /tmp/No7MbpTruX/ref.bib_31209.utf8, line 13, warning: 43 characters of junk seen at toplevel INFO - Overriding locale 'en-US' defaults 'variable = shifted' with 'variable = non-ignorable' INFO - Overriding locale 'en-US' defaults 'normalization = NFD' with 'normalization = prenormalized' INFO - Sorting list 'nty' of type 'entry' with scheme 'nty' and locale 'en-US' INFO - No sort tailoring available for locale 'en-US' INFO - Writing 'mwe.bbl' with encoding 'ascii' INFO - Output to mwe.bbl INFO - WARNINGS: 1 How to select kernel for SVM? Make Excel open some hyperlinks with non-default browser A bunch of our network/server/storage hardware uses web interfaces for their administrative portals. I'm currently using an Excel 2010 worksheet to keep track of each device. I have one column set aside to list the URL for each web interface. This makes it easy to simply click the URL to open each administrative portal.  My default browser is Firefox. However, some of the administrative portals don't play well with Firefox and require the use of IE. Until now, when I want to open a hyperlink in IE, I have to manually open IE, copy the URL from the Excel worksheet, and paste it into the IE address bar (otherwise it will open in Firefox if I simply click it). It's just an annoying extra couple of steps.  So without changing Firefox as my default browser, is there a simple way in Excel 2010 to tell it which hyperlinks to open in IE when they are clicked? I want to choose specifically which links open in which browser  (For reference I'm using Windows 7 Enterprise 64-bit) passing values between forms (winforms) Hearing a sound backwards because of Doppler effect Finding $\lim_{n\to\infty}\binom{2n}{n}$ I found a limit problem which is $\lim_{n\to\infty}{2n \choose n}$ as we know that $\sum_{i=0}^{n}{n \choose i}^2={2n \choose n}$ now we could transform the given problem as $\lim_{n\to\infty} \sum_{i=0}^{n}{n \choose i}^2$ and as $\sum_{i=0}^{n}{n \choose i}^2$ is a polynomial in $n$, therefore, $\lim_{n\to\infty}\sum_{i=0}^{n}{n \choose i}^2=\infty$ Please tell me if my solution is correct or not,and if it is incorrect then please provide me a solution.  Thanks Structuring game narrative. Handling NPC, Quest, General Dialogue. Is Json/XML the right way to go? Or any other solutions? Hello guys I'm try to make some games that have more to it than just simple high score scrolling shooters etc.  I'm trying to design my own systm of handling narrative. I want to be able to place NPC's in the game world, with scripts attached to them. Some of the NPC's would just have n random greetings. Others will be mission givers and will offer you a quest of sorts. (The quest could be go speak to Bob in the pub, or it might be bring me the Holy Grail and Crown Jewels, or something in between).  I've wracked my brain for a long while over this but sadly keep slipping back to the only way I know how, which is to manually code all the strings that people can say and have a horrible web of if statements and other such insanity to give me a rudimental dialogue system. Its not good enough even with just a few characters, but if I had dozens/hundreds of characters it would be even worse.  I've read lots about it already but I'm still very confused when I start trying on my own project. I've read that Json/XML might be the way to go and that I can add custom markups in the Json text to call methods in my code, but I dont even know if this is right and if so how I can do it.  The back of my brain is screaming at me that there is a simpler way to do it, but I've sat here for a very long time without managing to think of ideas.  Here is a diagram I drew which pretty much shows the flow of how I want my NPC to behave. If anyone can see this and then tell me how they might do something like this that would be fantastic!! (note: if Json is the correct advise, please give me a exact example of how exactly to format the Json in order to check the bools I mention in my flowchart - thanks!):    note: The circles denote an output from the data as Text for the dialogue system. The bools will need to be checked against by the data file to see which output to give (hope that makes sense and is possible) I am trying to pass a member function within a class to a function that takes a member function class pointer.  The problem I am having is that I am not sure how to properly do this within the class using the this pointer.  Does anyone have suggestions?  Here is a copy of the class that is passing the member function:  class testMenu : public MenuScreen{ public:  bool draw;  MenuButton&lt;testMenu&gt; x;  testMenu():MenuScreen("testMenu"){     x.SetButton(100,100,TEXT("buttonNormal.png"),TEXT("buttonHover.png"),TEXT("buttonPressed.png"),100,40,&amp;this-&gt;test2);      draw = false; }  void test2(){     draw = true; } };   The function x.SetButton(...) is contained in another class, where "object" is a template.  void SetButton(int xPos, int yPos, LPCWSTR normalFilePath, LPCWSTR hoverFilePath, LPCWSTR pressedFilePath, int Width, int Height, void (object::*ButtonFunc)()) {      BUTTON::SetButton(xPos, yPos, normalFilePath, hoverFilePath, pressedFilePath, Width, Height);      this-&gt;ButtonFunc = &amp;ButtonFunc; }   If anyone has any advice on how I can properly send this function so that I can use it later. From the spell description:     Sleep (...) Creatures within 20 feet of a point you choose within range are affected in ascending order of their current hit points (ignoring unconscious creatures). Starting with the creature that has the lowest current hit points,(...) Subtract each creature’s hit points from the total before moving on to the creature with the next lowest hit points. A creature’s hit points must be equal to or less than the remaining total for that creature   to be affected. Undead and creatures immune to being charmed aren’t affected by this spell. (PH p.276)   Now, to build the ascending order of their current hitpoints, the spell instructs to count everyone in area of effect, but only ignore unconscous creatures. Then later on it says that Undead and creatures immune to being charmed aren't affected.  Are those two latter kinds of creatures excluded from the roll of current HP by default? Following the "if they were it would say so" philosophy of Sage Advice, it doesn't seem so to me. why this code can run ? double a[3]; a[1,1]=1; $\mathbb{Q}(\sqrt{p},\sqrt[3]{q})= \mathbb{Q}(\sqrt{p}\cdot \sqrt[3]{q})$ ?? If APS-C and similar crop-sensor digital cameras have a focal length multiplying effect such that a 50mm lens has an apparent focal length closer to the field of view of an 80mm on a full frame camera, and yet at the same time the depth of field for the smaller sensor camera is more like the depth of field a 50mm lens would produce on a full frame camera (using the same aperture), then this would seem to suggest the concept of an "aperture dividing effect."  In other words, a 50mm f/1.8 lens on an APS-C camera would act more like a 80mm f/2.8 (approx. 1.8 * 1.6x) lens in 35mm equivalent — for depth of field, not considering exposure.  Can someone with a better understanding of the physics involved clarify this for me.  I've never seen this concept explicitly mentioned anywhere, so I am a bit suspect of it. Since there are gravitational lenses, are there gravitational mirrors? Gravitational lensing is an observed phenomenon. Can one have a gravitational mirror?   A slightly unrelated question: Can gravitational waves be reflected? What is the difference between a homepage link with or without a trailing slash? Is there any way to automatically unwrap UV map proportionally to object or "world" size?  For example:  I've made two cubes, one is two times bigger than other (scale is applied). Then I unwrapped texture with Smart UV project which will try to span all faces on whole texture space(0 to 1) so bricks on left cube will be bigger than bricks on right cube.   But what I want to achieve is this:     In broader context:  When I import model from Archicad (in form of OBJ) all objects have UV's in some scale (so all bricks have the same size on every imported object). And when I want to create custom object in scene I have to manually scale UV's to adjust bricks size for every new object (instead of scaling to one constant parameter). What's the Best Way to Shuffle an NSMutableArray? If you have an NSMutableArray, how do you shuffle the elements randomly?  (I have my own answer for this, which is posted below, but I'm new to Cocoa and I'm interested to know if there is a better way.)    Update: As noted by @Mukesh, as of iOS 10+ and macOS 10.12+, there is an -[NSMutableArray shuffledArray] method that can be used to shuffle. See  for details. (But note that this creates a new array, rather than shuffling the elements in place.)