How do I find my maximum precision on my computer?
A problem about function N
How do I limit the number of rows returned by an Oracle query after ordering? Is there a way to make an Oracle query behave like it contains a MySQL limit clause? In MySQL, I can do this: select *  from sometable order by name limit 20,10  to get the 21st to the 30th rows (skip the first 20, give the next 10). The rows are selected after the order by, so it really starts on the 20th name alphabetically. In Oracle, the only thing people mention is the rownum pseudo-column, but it is evaluated before order by, which means this: select *  from sometable where rownum &lt;= 10 order by name  will return a random set of ten rows ordered by name, which is not usually what I want. It also doesn't allow for specifying an offset. Why does a query run slower in a Stored Procedure than in the Query window? Analyze a circuit with two diodes and two voltage rails I want to find \$I\$, \$I_{D2}\$ and \$V\$ in this circuit. The diodes are made of Silicium. I'm a beginner and normally I would assume the Diode bias and then apply KVL to see if it is true. However, I've only encountered circuits where the wire forms a loop.    How am I supposed to apply KVL in this case? If voltage is the difference in potential between two points, how can I find the voltage of V if one point is outside of the circuit, therefore, outside of KVL application? I have this input:  sdkxyosl 1 safkls 2 asdf--asdfasxy_asd 5 dkd8k  jasd 29 sdi44sw 43 asasd afsdfs 10 rklyasd 4   I need this output:  sdi44sw 43 dkd8k  jasd 29 asasd afsdfs 10 asdf--asdfasxy_asd 5 rklyasd 4 safkls 2 sdkxyosl 1   So i need to sort the lines by the last column.  I don't know how many columns are in one line.  I just can't figure it out, how to do it. I don't have "perl powers". I just have ~average scripting powers with sed, awk, cut, etc..   Does somebody know how to do it? I work at a nursery and I have a hard time managing the toys that the kids play with. I watch them put things in their mouths, cough and sneeze on the toys, and throw everything on the ground. Even though I see all of these things, it is hard to find the time to clean all of the toys, simply because there are too many and I do not have that much time. Any input would be appreciated! Is the sizeof(some pointer) always equal to four? How do I concatenate JavaScript files into one file? How do I prevent directories mounted with 'bind' from appearing on 'Devices' on nautilus? I have these lines in the fstab   # binds /media/DataNtfs/Music           /home/can/Music                  none    rw,bind  /media/DataNtfs/Pictures        /home/can/Pictures               none    rw,bind  /media/DataNtfs/Downloads       /home/can/Downloads              none    rw,bind  /media/DataNtfs/Documents       /home/can/Documents              none    rw,bind  /media/DataNtfs/Backups         /home/can/Backups                none    rw,bind  /media/DataNtfs/Notes           /home/can/Notes                  none    rw,bind  /media/DataNtfs/Other           /home/can/Other                  none    rw,bind  /media/DataNtfs/Packages        /home/can/Packages               none    rw,bind  /media/DataNtfs/Photos          /home/can/Photos                 none    rw,bind  /media/DataNtfs/Videos          /home/can/Videos                 none    rw,bind  /media/DataNtfs/WorkSpace       /home/can/WorkSpace              none    rw,bind How do I use large bitmaps in .NET? I'm trying to write a light-weight image viewing application. However, there are system memory limitations with .NET.  When trying to load large bitmaps (9000 x 9000 px or larger, 24-bit), I get a System.OutOfMemoryException. This is on a Windows 2000 PC with 2GB of RAM (of which 1.3GB is used up). It also takes a lot of time to attempt loading the files.  The following code generates this error:  Image image = new Bitmap(filename); using (Graphics gfx = this.CreateGraphics()) {     gfx.DrawImage(image, new Point(0, 0)); }   As does this code:  Stream stream = (Stream)File.OpenRead(filename); Image image = Image.FromStream(stream, false, false); using (Graphics gfx = this.CreateGraphics()) {     gfx.DrawImage(image, new Rectangle(0, 0, 100, 100), 4000, 4000, 100, 100, GraphicsUnit.Pixel); }   Also, it is enough to do just this:  Bitmap bitmap = new Bitmap(filename); IntPtr handle = bitmap.GetHbitmap();   The latter code was intended for use with GDI. While researching this, I found out that this is in fact a memory issue where .NET tries to allocate twice as much as is needed in a single contigous block of memory.    I know from other applications (Internet Explorer, MS Paint etc.) that it IS possible to open large images, and rather quickly. My question is, how do I use large bitmaps with .NET?  Is there anyway to stream them, or non-memory load them? Codomain of function complete implies function space complete Let $(X,d_X)$ and $(Y,d_Y)$ be two metric spaces.   Let $(C_b(X,Y), d_C)$ be a function space with the metric $$d_C(f,g):=\sup\limits_{x\in X} d_Y(f(x), g(x)).$$  Prove that if $(Y,d_Y)$ is complete then $(C_b(X,Y), d_C)$ is complete.  Unfortunately, I have no idea how to approach this problem. I can think of something like this:  Let $(y_k)_k\subset Y$ be a Cauchy sequence converging to $y\in Y$. Then there exists some $f\in C_b(X,Y)$ such that $f(x_k)=y_k$ for all $k\in \mathbb N$. Since $f$ is continuous, $\lim\limits_{k\to\infty} d_Y(f(x_k), y)=0$.  But how do I go from here? As far as I understand, what needs to be proved is that any Cauchy sequence of functions in $C_b(X,Y)$ converges in $C_b(X,Y)$, that is, that the limit is bounded and continuous. But how do we devise such a sequence of functions? What apps are people using to record voice meetings on the iPad? I installed Opera 12.16 from a .deb for reasons. Just assume that I need this specific browser of this specific version and that there’s no alternative.  However, that deb depends on packages (such as the gstreamer0.10 series) which are not in my distribution anymore (Debian testing). This makes apt fail on every operation except apt remove opera with dependency errors:  # apt install cli-common Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies:  opera : Depends: gstreamer0.10-plugins-good but it is not installable          Recommends: flashplugin-nonfree but it is not going to be installed E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).   apt --fix-broken install will just propose to remove opera:  # apt --fix-broken install Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages will be REMOVED:   opera 0 upgraded, 0 newly installed, 1 to remove and 92 not upgraded. 1 not fully installed or removed. After this operation, 46.6 MB disk space will be freed. Do you want to continue? [Y/n]   Currently, my workaround is to install Opera when I need it, and remove it as soon as anything else needs to be done with apt. This is annoying.  Any suggestions? Ideally, I’d like to make apt ignore the dependencies of opera forever, since it works well-enough for my purposes. Exercise on infinite series: pointwise product between convergent serie and unbounded sequence I am not able to solve this exercise. I've tried everything.     Exercise Let be $a_n &gt; 0$ a sequence and suppose that $\sum a_n$ converges. Prove that exists a sequence $c_n &gt; 0$ such that $\lim c_n = \infty$ and $\sum c_na_n &lt; \infty$   I don't even know if I have to find an "always-valid" closed form for $c_n$ (maybe in function of $a_n$?) or prove its existence in another way.  Thanks in advance. What is a good method for short text clustering? I am working on a text clustering problem. The data contains several sentences. Is there a good algorithm which reaches high accuracy on short text?  Can you provide good references?   Algorithms such as KMeans, spectral clustering does not work well for this problem. Wine or virtual machine (VirtualBox) to run apps (eg. Photoshop) I am wondering if it will be better (stability, convenience and speed) to run apps like Photoshop with Wine or a virtual machine like VirtualBox? How to allow Page Up in GNU Screen? I use Vim to edit text files on Linux. Commonly I connect to remote Linux machines using PuTTY from Windows.  I use GNU Screen commonly as well.  When using Vim inside Screen I am unable to use the Page Up key because Screen interprets it as a command to start copy mode.    I would like to use Page Up for its regular up-paging functionality.  How can I configure Screen to do this? Evaluate the integral $\int_0^\infty \frac{dx}{\sqrt{(x^3+a^3)(x^3+b^3)}}$ I have two raster files that are the same cell size but I cannot get them to align properly. (I want the black to line up with the pink)    When creating the black raster file (from using polyline to raster), I imported the pink raster in the Snap Raster section in the Environments setting. I thought that Snap Raster was supposed to make it line up?  Am I doing something wrong or is it a bug in Arc (I remember reading that this was a problem about two years ago), and if it is a bug is there a work around?  I have also read there is a Raster Shift, but I'm not sure what to enter in the X Coordinate and Y Coordinate. Since I only want the black raster to shift down, I know that the X Coor = 0 and the Y Coor should be negative something, but what are the units?  Thanks. How to change the title of ToC? I need to change default title of ToC. Is it possible with titlesec package? Here is my MWE:  \documentclass{book}  \usepackage{titlesec} \titleformat{\chapter}{\normalfont\Large\scshape}{\thechapter}{1em}{} \vspace{6pt}]  \usepackage{lipsum}   %-------------------------------------------------------------------------  \begin{document}   \newpage \thispagestyle{empty} \tableofcontents \thispagestyle{empty} \newpage \thispagestyle{empty}  \setcounter{footnote} {0}\chapter*{{\fontsize{11}{14}\selectfont\normalfont{Author1} \\ {\scshape\Large Title}}} \addcontentsline{toc}{chapter}{\normalsize\normalfont{Author1} \\ \normalfont\scshape{Title}} \thispagestyle{empty} \Author{Author1} \Title{Title} \lipsum \newpage \thispagestyle{empty}    \end{document} Notes:  Answers will occasionally be moved to the  when there are too many of them. When using them to report bugs, keep an eye on the post.    This site, Meta Stack Exchange, is usually used as a &quot;test bed&quot; for pending changes happening to the way text is rendered on all network sites. Changes to text rendering that are going to be rolled out to the network are usually deployed here first to test them out and fix any potential glitches. Currently, there are no such changes pending, but if there were, keep in mind that text posted here may render differently from the other sites until the changes roll out to them as well.    As per Jeff's suggestion in : You can use this question as a formatting sandbox. You can:  edit  itself ( questions such as this one require only 100 reputation to edit instead of 2,000) post answers to this question (This question might be , requiring earning 10 reputation on this site to answer) post comments to this question or its answers test suspected bugs with the editor or the rendering post ponies (only when mods are asleep)   Beware that since the  in December 2010, and  added in March 2011, no syntax highlighting is applied unless the question's tags or an inline hint enable it. So, to test highlighting here in the sandbox:  , you can use GitHub-flavor fenced code blocks in your posts, specifying the language after the opening fence: ```html While not hinted otherwise: &lt;html&gt;&lt;/html&gt; source &lt;b&gt;goes&lt;/b&gt; &quot;here&quot;. ```  ```js var a = 3; while (not (a &gt; 0)) {     alert(&quot;JavaScript code &lt;b&gt;goes&lt;/b&gt; here.&quot;); } ```   Or:  Create code blocks in any way (using the fence notation above, the four-space indent form, or using HTML &lt;pre&gt;&lt;code&gt; tags).  Save your post.  Use your browser's developer tools to edit the resulting HTML. To open developer tools, press F12, or ⌥⌘ I on Mac.  Find the &lt;pre&gt; element and add the attribute class=&quot;prettyprint&quot;, or change it into one of the valid syntax hints linked above, like class=&quot;lang-vb prettyprint&quot;.  Run the following in the location bar: javascript:prettyPrint(); or prettyPrint() in the console.     Answers that are considered annoying or obnoxious, or that cause breakage for users, will be deleted. This is .