It's a very simple code. I compiled and run this code in code blocks and the output was 11111111111111112.000000. I run this code also in . This time the output was same. But why it doesn't work properly? How can I solve this problem? Here's my code. #include &lt;stdio.h&gt; int main() {  double a = 11111111111111111;  printf(&quot;%lf\n&quot;, a);  return 0; }
Consider the following code:   0.1 + 0.2 == 0.3  -&gt;  false   0.1 + 0.2         -&gt;  0.30000000000000004   Why do these inaccuracies happen?
When speaking precisely or technically, one would say that "Homo erectus and homo sapiens are two species of hominid" rather than "Homo erectus and homo sapiens are two species of hominids." The hominid here should be singular because we are speaking about instances of a single class ("class" being used here in its broader sense, not in the sense of taxonomic grouping).  Now let's consider more common parallel constructions replacing the word species with other words.      Tide and Wisk are two brands of detergent.       Tide and Wisk are two brands of detergents.      Cats and dogs are two types of pet you can buy at Pets-R-Us.       Cats and dogs are two types of pets you can buy at Pets-R-Us.   I feel that using the singular noun to specify the class is more grammatically correct, but sounds stilted in conversation. Almost everyone I hear making these constructions uses the plural form. What are your thoughts about singular vs. plural here?  Edit  Here's a more extreme example that may help clarify the issue. Consider the following sentence:     It was my first attempt at calming an angry crowd, and I just        stood there while people were hurling all kinds of insults at me.   Here I think the singular insult sounds strange, if not downright wrong.  Further Edit  I just noticed in A Treasury for Word Lovers (Morton S. Freeman, 1983) a section entitled "Types of Errors." This is a book about (American) English usage by an English professor and editor, which purports to be a "practical guide for serious writers and readers." I wish I could say this discovery satisfies the question, but in fact I now feel somewhat farther from the truth, if there is any single "truth" in this matter. But at least I don't have to worry about being wrong when using the plural form of the class in these constructions. Why do we say "is it" when asking a question rather than "it is"? How can I prevent my mail from being classified as spam? How to install CUDA 8.0 on Ubuntu 16.04 with Nvidia GeForce GTX 1080 I am attempting to install CUDA 8.0 within Ubuntu 16.04 for the Nvidia GeForce GTX 1080. I had CUDA 7.5 installed, but it did not appear to be compatible with the GTX 1080. I downloaded the .run installer from Nvidia's developer page, but the installation fails and outputs the following to a nvidia-installer.log     An NVIDIA kernel module 'nvidia-drm' appears to already be loaded in     your kernel.  This may be because it is in use (for example, by an X     server, a CUDA program, or the NVIDIA Persistence Daemon), but this     may also happen if your kernel was configured without support for     module unloading.  Please be sure to exit any programs that may be     using the GPU(s) before attempting to upgrade your driver.  If no     GPU-based programs are running, you know that your kernel supports     module unloading, and you still receive this message, then an error     may have occured that has corrupted an NVIDIA kernel module's usage     count, for which the simplest remedy is to reboot your computer.   I have rebooted the computer, but that did not resolve the problem. How do I unload the 'nvidia-drm' module so that I can install the 8.0 CUDA? Splitting raster into smaller chunks using GDAL? I have a raster (USGS DEM actually) and I need to split it up into smaller chunks like the image below shows. That was accomplished in ArcGIS 10.0 using the Split Raster tool. I would like a FOSS method to do this. I've looked at GDAL, thinking surely it would do it (somehow with gdal_translate), but can't find anything. Ultimately, I'd like to be able to take the raster and say how large (4KM by 4KM chunks) I would like it split up into. How to connect a Nokia Lumia 730 to Ubuntu 14.04? How do I check whether a file exists without exceptions? How do I check whether a file exists or not, without using the  statement? How to create an annuity timeline on LaTeX I was wondering, how can I create a timeline exactly like this one:    on LaTeX?  I am a Finance student, and write all of my notes using LaTeX. These timelines, are giving me a headache. Since we use a lot of different timelines because of annuities. I want to learn how to create one basic timeline, so that I can then change anything I want. But basically, I want something like this, with the arrows and everything.  Thank you so much guys! In thinking about Sturm-Liouville theory a bit I see I have no actual idea what is going on.  The first issue I have is that my book began with the statement that given  $$L[y] = a(x)y'' + b(x)y' + c(x)y = f(x)$$  the problem $L[y] \ = \ f$ can be re-cast in the form $L[y] \ = \ \lambda y$.  Now it could be a typo on their part but I see no justification for the way you can just do that!  More importantly though is the motivation for Sturm-Liouville theory in the first place. The story as I know it is as follows:  Given a linear second order ode   $$F(x,y,y',y'') = L[y] = a(x)y'' + b(x)y' + c(x)y = f(x)$$  it is an exact equation if it is derivable from a differential equation of one order lower, i.e.  $$F(x,y,y',y'') = \frac{d}{dx}g(x,y,y').$$  The equation is exact iff  $$a''(x) - b'(x) + c(x) = 0. $$  If $F$ is not exact it can be made exact on multiplication by a suitable integrating factor $\alpha(x)$.  This equation is exact iff  $$(\alpha(x)a(x))'' - (\alpha(x)b(x))' + \alpha(x)c(x) = 0 $$  If you expand this out you get the Adjoint operator  $$L^*[\alpha(x)] \ = \ (\alpha(x)a(x))'' \ - \ (\alpha(x)b(x))' \ + \ \alpha(x)c(x) \ = 0 $$  If you expand $L^*$ you see that we can satisfy $L \ = \ L^*$ if $a'(x) \ = \ b(x)$ &amp; $a''(x) \ = \ b'(x)$ which then turns $L[y]$ into something of the form  $$L[y] \ = \ \frac{d}{dx}[a(x)y'] \ + \ c(x)y \ = \ f(x).$$  Thus we seek an integratiing factor $\alpha(x)$ so that we can satisfy this &amp; the condition this will hold is that $\alpha(x) \ = \ \frac{1}{a(x)}e^{\int\frac{b(x)}{a(x)}dx}$  Then we're dealing with:  $$\frac{d}{dx}[\alpha(x)a(x)y'] \ + \ \alpha(x)c(x)y \ = \ \alpha(x)f(x)$$  But again, by what my book said they magically re-cast this problem as  $$\frac{d}{dx}[\alpha(x)a(x)y'] \ + \ \alpha(x)c(x)y \ = \ \lambda \alpha(x) y(x)$$  Then calling  $$\frac{d}{dx}[\alpha(x)a(x)y'] \ + \ ( \alpha(x)c(x)y \ - \ \lambda \alpha(x) )y(x) \ = \ 0$$  a Sturm-Liouville problem.  My question is, how can I make sense of everything I wrote above? How can I clean it up &amp; interpret it, like at one stage I thought we were turning our 2nd order ode into something so that it reduces to the derivative of a first order ode so we can easily find first integrals then the next moment we're pulling out eigenvalues &amp; finding full solutions - what's going on? I want to be able to look at $a(x)y'' \ + \ b(x)y' \ + \ c(x)y \ = \ f(x)$ &amp; know how &amp; why we're turning this into a Sturm-Liouville problem in a way that makes sense of exactness &amp; integrating factors, thanks for reading! How to enable projection transformation in QGIS My QGIS project has two layers, one layer is retrieved by Google layer plugin which fetches the static Google map image whose CRS is +proj=merc +lon_0=0 +lat_ts=0 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +units=m +no_defs and another vector layer is a postgis layer whose CRS is +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs.  I digitalized some polygon features from Google Layers and added it to the vector layer. However, QGIS seems do not make the automatic CRS transformation. How can I change its projection?   Thanks What animal is a “weefil”? What animal is depicted in this image labelled “weefil”? Command/macro name cannot include numbers and symbols I would like put picture into table, and my idea is define new command as below>   \newcommand{\EJ471}{\includegraphics[scale=0.150]{EJ_471.jpg}}   But compiler reports an error. If I use the command name for example \EJa, everything is all right. I've read similar questions as      But still I don't understand why it does not work. Press-and-hold or Long-Press Gestures: Unintuitive? Often, I find people struggle with the usage of press-and-hold gestures on mobile/web platforms. The mere thought of having a user press on a defined object and hold for an arbitrary amount of time before the product reacts seems overtly complicated and unobtrusive. My questions are:   For what use cases do press-and-hold gestures best fit? Have there been published studies with regards to press-and-hold gesture intuition? Are there more viable alternatives to this system? I've got a road bike with brake lever shifters, and it's developed a small problem with age: sometimes, the shifter doesn't catch the first time or two I push it. It'll move easily, with no resistance, since it's not actually pulling on the cable, then after a few tries, catch and work normally. The colder the temperature, the more often this happens.  I don't know how the mechanism works internally, so I'm curious what would cause this, and also whether it's (as I suspect) gradual wear of some part of the mechanism, and if it's likely to fail catastrophically, or gradually worsen. The relation between acceleration and inertial force How to select distinct field values using Solr? Entire function $f$ such that $|f(z)| ≤ K |z|^3$ for $|z|\ge1$ and $f(z) = f(iz)$ for every $z∈C$ Let $f(z)$ be an entire function such that for some constant $K$ , $|f(z)| ≤ K$ $|z|^3&lt;$ for $|z|\ge1$ and $f(z) = f(iz)$ $∀z∈C$ , then which of the following are correct ?  (A)$ f(z) = Kz^3$ $∀ z∈\Bbb{C}$ (B) $f(z)$ is a constant function (C) $f(z)$ is quadratic function (D) No such $f$ exists   My attempt : I can deduce that since $f(z) = f(iz)$ and since $i^4=1 \implies f$ must involve only fourth powers of $z$ . Hence $f(z)=a_1z^4+b_1z^8+c_1z^{16}+ \cdots $-------(1)  Also for $|z| \ge 1 $: let C.   Then $|g(z)| = |f(z)|/|z^3| \le k$ => By the Cauchy estimate theorem we can prove that :  $f(z)/z^3$ is a constant function $= c $   $\implies f(z)=cz^3$ for $|z| &gt; 1$     ...........(2)  From (1) and (2) ; we get  there does not exist a function like this ?  My textbook answer says it's a constant function ? Are there gotchas using varargs with reference parameters I have this piece of code (summarized)...  AnsiString working(AnsiString format,...) {     va_list argptr;     AnsiString buff;      va_start(argptr, format);     buff.vprintf(format.c_str(), argptr);      va_end(argptr);     return buff; }   And, on the basis that pass by reference is preferred where possible, I changed it thusly.  AnsiString broken(const AnsiString &amp;format,...) { ... the rest, totally identical ... }   My calling code is like this:-  AnsiString s1, s2;     s1 = working("Hello %s", "World");     s2 = broken("Hello %s", "World");   But, s1 contains "Hello World", while s2 has "Hello (null)". I think this is due to the way va_start works, but I'm not exactly sure what's going on. "An SQL Server database schema" or "a SQL Server database schema"? Possible Duplicate:          I got the following sentence from the book I'm reading:     You can take a database-first approach   by first creating a SQL Server   database schema.   From what I learned, I think it should be "an SQL Server database schema", not "a SQL Server database schema". So which one is correct? Javascript - alert("zoo">"house") returns true