Aloccating free space
How to extend my root (/) partition?
Is there any way to call the parent version of an overridden method? (C# .NET) In the code below I tried in two ways to access the parent version of methodTwo, but the result was always 2. Is there any way to get the 1 result from a ChildClass instance without modifying these two classes?  class ParentClass {     public int methodOne()     {         return methodTwo();     }      virtual public int methodTwo()     {         return 1;     } }  class ChildClass : ParentClass {     override public int methodTwo()     {         return 2;     } }  class Program {     static void Main(string[] args)     {         var a = new ChildClass();         Console.WriteLine("a.methodOne(): " + a.methodOne());         Console.WriteLine("a.methodTwo(): " + a.methodTwo());         Console.WriteLine("((ParentClass)a).methodTwo(): "          + ((ParentClass)a).methodTwo());         Console.ReadLine();     } }   Update ChrisW posted this:     From outside the class, I don't know   any easy way; but, perhaps, I don't   know what happens if you try   reflection: use the Type.GetMethod   method to find the MethodInfo   associated with the method in the   ParentClass, and then call   MethodInfo.Invoke   That answer was deleted. I'm wondering if that hack could work, just for curiosity. How to understand the drawbacks of K-means K-means is a widely used method in cluster analysis. In my understanding, this method does NOT require ANY assumptions, i.e., give me a dataset and a pre-specified number of clusters, k, and I just apply this algorithm which minimizes the sum of squared errors (SSE), the within cluster squared error.  So k-means is essentially an optimization problem.  I read some material about the drawbacks of k-means.  Most of them say that:   k-means assumes the variance of the distribution of each attribute (variable) is spherical;  all variables have the same variance; the prior probability for all k clusters is the same, i.e., each cluster has roughly equal number of observations;   If any one of these 3 assumptions are violated, then k-means will fail.  I could not understand the logic behind this statement. I think the k-means method makes essentially no assumptions, it just minimizes the SSE, so I cannot see the link between minimizing the SSE and those 3 "assumptions". How FluentWait is different from WebDriverWait? How is the FluentWait is different from WebDriverWait? I am using WebDriverWait having the polling interval set to : 500 miliseconds. Still, WebDriverWait returns after some delay (i.e. 2 - 3 seconds after the element load is completed)? Any opinion here? Are there other explanations for slow tyre pressure loss? I rode my road bike on Friday and the tyres were at the correct pressure then, around 100psi.  On Tuesday, I jumped on without checking them and quickly realised something was wrong with the rear tyre.  It wasn't completely flat but was fairly soft.  I hadn't gone far so went home and took the car to work instead.  When I got home later, I was surprised to find the tyre, while still soft, hadn't lost all pressure by any means.  It was around 40psi and felt the same as when I left it in the morning.  I decided there must be a slow leak somewhere, but I couldn't find one anywhere, putting the inner under water and going around it methodically looking for bubbles.  I've never failed to find a leak before that way.  I've switched it out anyway because I don't want to mess around with my commute, but I'm curious ... is there another explanation for that amount of pressure loss?  Or must there have been a puncture somewhere that I missed somehow?  The tyres (whole bike) are pretty new and in excellent condition. Constraint the camera to look at an object In my scene I have a camera sitting at the origin. I would like to contraint it so that it always looks at the center of a given object. But the camera should not change its position.  I found some answers using a "TrackTo" or "LockedTrack" constraint but could not manage to make it work.  Could I probably use a Driver for this and if yes, how can I adjust it?  Thanks in advance! A particular big Delta I would like to insert the below mathematical symbol, it looks like a big Delta but different. Is there command to obtain a similar shape? File names for JSP include directive to avoid compilation of them Is Myopia Reversible/Curable? How to determine an object's class? Adding HTML5 placeholder to all drupal forms I'm trying to add the placeholder attribute to all textfields across my website, but I'm having no luck.  I've created a module that overrides hook_form_alter  function mymodule_form_alter(&amp;$form, &amp;$form_state, $form_id) {     foreach ($form as $key =&gt; $value) {         if ("textfield" == $value["#type"]){             $value['#attributes']["placeholder"] = t($value["#title"]);         }     } }   I should tell you that I'm also using the webform module. Shrink the database only up to its initial size which is set after creating database In SQL server every database has a property Initial Size (MB) which can be seen in properties of database in SSMS. By default it will be 3 MB for mdf and 1 MB for ldf file.  So now if create a new database then it will be set to default size(i.e 3 MB for mdf and 1 mb for ldf file). But after creating the database  I change the initial size to some other value say For mdf 10 MB and ldf 5 MB.(In real-time some database administrator may want to change initial after creating database)  But now if shrink the database it will shrink beyond the initial size I have set after creation(consider that no data is there in database otherwise it will shrink to its actual content size). It will shrink till the initial size it had during creation of database(i.e 3mb for mdf and 1 mb for ldf). I was expecting to shrink till the initial size which I have set(i.e 10 mb for mdf and 5mb for ldf). Can it be possible to do? If possible then how?  In some article i saw like dbcc SHRINKFILE can be used to shrink beyond initial size and dbcc SHRINKDATABASE cannot shrink beyond initial size. But I want to shrink only till the initial size to which I have set.  Note: I know that shrink is bad and should not be done.But I want to know how it can be done? If sql server considers only the initial size set during creation of database then what is the use of setting the initial size after creating database?  EDIT:  From microsoft shrink related article: Using DBCC SHRINKDATABASE you can not shrink database below its initial size.  My question is Can I change the initial size of existing database itself?  EDIT:  I have about 5 sql server instance. All the database where created with default size of 3 mb for data and 1 mb for log(about 3 years back). Now all the databases are in the range of 100-1000 mb. I wont shrink the database normally as it is not good practice. But some database grow more than 10 GB(mdf file itself as i insert so much data in it). So when database is large I will shift unimportant and old contents from this database to another server as it is not required in that server for me. So that database size reduces from 10 GB to 1 GB. Now the remaining 9 Gb left unused. Now I  want to specify database size to be reduced to 2 GB so that i will get 1 GB free space(Also 2 Gb is the ideal size for this database), Which can be used to avoid autogrowth till next 1 Gb of data is filled. Also i have set 100 MB auto-growth for this kind of large database which has more writes. So instead of specifying size as 2 GB in shrinkfile command,if it was possible to change initial size to 2 GB (which shrink considers) then it would have been better. During this database creation there was no plan about size ,autogroth etc. As it was created about 3 years back. Now i am planning to set autogrowth etc. I cant again create new database with new initial size and shift data. So I was asking whether I can change the Initial size for existing database? What does "65" mean? K-2SO beats up the troopers easily. Up in the sky, the bombers are preparing to attack. Just as they start the attack run, TIE fighters come in from the shield and swarm the rebel fleet.  JON VANDER (GOLD LEADER): Red Leader, this is Gold Leader, we’re starting our attack run on the  shield gate. Keep it tight and watch out for those towers. GOLD PILOT: More fighters. Form up, at 65.  What does &quot;65&quot; mean? Does a constantly accelerating charged particle emit EM radiation or not? What event log should I check for Hardware Changes The difference between sys.stdout.write and print? Clickable Table Footnote I'm trying to have some clickable footnotes within tables. I tried using \footnote{}, it does create a link but there's no footnote text associated with it. \footnotemark[number] along with \footnotetext[]{} does create a fotenote but then there's no hyperlink. (I would like to make it clear that I'm trying to have footnotes at the bottom of the page and not footnotes within the table.)  Here's a small code snippet:  \documentclass{report}  \usepackage{hyperref} \begin{document}  \begin{table}[h!]     \centering     \begin{tabular}{|r|r|r|}         \hline         A\footnote{Test!} &amp; B\footnotemark[4] &amp; C\footnotemark[5]\\         \hline         123 &amp; Tim &amp; Jane\\         \hline         456 &amp; Tom &amp; Jung\\         \hline     \end{tabular}     \caption{A table} \end{table}  This is a clickable footnote\footnote{You clicked me!}.  \footnotetext[4]{This is B} \footnotetext[5]{This is C}  \end{document} Determinant of a $2\times 2$ block matrix I would like to know the proof for:  The determinant of the block matrix $$\begin{pmatrix} A &amp; B\\ C&amp; D\end{pmatrix}$$ equals $$(D-1) \det(A) + \det(A-BC) = (D+1) \det(A) - \det(A+BC)$$ when $A$ is a square matrix, $D$ is a scalar, $C$ is a row vector and $B$ is a column vector.  I appreciate your help. How to make the BibTeX reference list visible in a LaTeX document Im very new at LaTeX and I would appreciate some help solving this problem. I have created a BibTeX file containing all references to a document. In this text file BibTeX items are inserted and no other text are written, for instance @article{...}. When I call for this bib file from the main.tex file I use the commands:  \bibliographystyle{plain} \bibliography{thebibliography}   Now to my question. All i get when I compile this main.tex is the title (bibliography) for this chapter, otherwise the textfield is blank. Is this error occurring because I should write anything in the bib file or have I missed any lines in the main.tex file. Best WPF open source projects I have programmed with WPF for more than a year. When I started there weren't so many examples and guidelines to follow, now the situation is much more better.  I would like to ask you some help in listing the best WPF (open) source code examples or projects that you suggest to study in order to learn more about project structure, best practices, etc.  Thank you, Marco I need to find the intersection point of 2 line segments (lines are finite, i.e., they have end points).   e.g. segment 1 from $(x_1, y_1)$ to $(x_2, y_2)$ -- segment 2 from $(x_3, y_3)$ to $(x_4, y_4)$  you can assume $m_1$ and $m_2$ are the gradients of segment 1 and segment 2 respectively  similarly, $c_1$ and $c_2$ being the y-intercepts of segment 1 and segment 2 respectively  Using $y=mx+c$ I can easily find the equations of both lines and then derive the intersection point from those equations and check if that point actually lies on both the line segments (intersection point may not lie between the end points).  My problem is when I calculate the gradients $m_1$ and $m_2$ I do $\frac{y_2-y_1}{x_2-x_1}$ there for if one of the lines is vertical then I am going to have problems. How can I deal with this?  Another problem is that if the two segments intersect at a point which is also the same as one of the end points then I want to assume that they are not intersecting.  e.g. if segment 1 is from $(2, 3)$ to $(3, 7)$ and segment 2 is from $(3, 7)$ to $(7, 3)$ then I want to assume they don't intersect.