I am trying to refactor a switch statement that is like this:  private void Validate(DataTypeEnum dataType, string value, ...) {     switch(dataType)     {         case DataTypeEnum.Number:             var typedValue = int.Parse(value);             //Validation of typedValue             break;         case DataTypeEnum.Decimal:             var typedValue = Decimal.Parse(value);             //Validation of typedValue             break;         case DataTypeEnum.DateTime:             var typedValue = DateTime.Parse(value);             //Validation of typedValue             break;     } }   I would like to get rid of the switch statement and somehow replace it with a more object oriented construct. Any suggestions?  My ideal would be something like this:  private void Validate(DataTypeEnum dataType, string value, ...) {     Validate(value); } private void (Decimal value) {     //Validate } private void (DateTime value) {     //Validate }   Is there any elegant way to fix this?
Seeing as C# can't switch on a Type (which I gather wasn't added as a special case because is relationships mean that more than one distinct case might apply), is there a better way to simulate switching on type other than this?  void Foo(object o) {     if (o is A)     {         ((A)o).Hop();     }     else if (o is B)     {         ((B)o).Skip();     }     else     {         throw new ArgumentException("Unexpected type: " + o.GetType());     } }
Selling a car with a lien I own a car personally, but it is mortgaged to a bank. I want to sell it to an individual. I haven't the funds to repay the loan until I'm paid for the car. The buyer doesn't want to pay me without a lien release (or guarantee that one is coming). The bank won't release the lien until it gets the funds. What do people do in a case like this? It must be a common case. What should I do? The subscript size for formulas in beamer presentation First of all sorry because this question may be duplicated. I don't know why the question was uploaded with another user's name and I can't edit it (may be you can delete the previous question with the same title). The question is the following:  I am creating a beamer presentation where I have a lot of formulas. Between the packages used I have \usepackage{amsmath} and the theme for the presentation is \usetheme{Warsaw}.  As it can be seen in the attached picture, the size of the sub(super)script is bigger than the normal writting.     Anyone knows a set of basic packages in order to get the classical formulas, without these size changes?  The code is the following  \documentclass[]{beamer}  \setbeamercovered{transparent}   %--------------------------% % To add enumeration index %--------------------------% \addtobeamertemplate{navigation symbols}{}{%     \usebeamerfont{footline}%     \usebeamercolor[fg]{footline}%     \hspace{1em}%     \insertframenumber / \inserttotalframenumber  } \setbeamercolor{footline}{fg=black} \setbeamerfont{footline}{series=\bfseries}   %---------------------------------------------------------------------------------%  \usepackage{amsmath,amssymb}    % Theme for the presentation \usetheme{Warsaw} % Change the colour \usecolortheme{spruce}  \setbeamertemplate{footline}{}  % Delete the footline with the names    \begin{document}    \begin{frame} \frametitle{\textbf{Algorithm}: step \texttt{s}}   \scriptsize  \textbf{STEP \texttt{s}}  \vspace{0.25cm}  Let $B^{(s-1)}$ be the variable  for the $\mathit{(s-1)}$-th step, let's take the sets $I_+^{(s-1)}$ and $I_-^{(s-1)}$ of length $r_+^{(s-1)}$ and $r_-^{(s-1)}$ respectively,and define:\\  \vspace{0.25cm}  \begin{center}  $B^{(s+)}= \sqrt{\tfrac{(r_+^{(s-1)} + 1)*r_-^{(s-1)}}{r_+^{(s-1)} + r_-^{(s-1)} + 1}} $  \end{center}   \end{frame}  \end{document} Bibliography with page numbers In GKP's Concrete Mathematics, there is a useful and interesting feature I would like to see in more books. The bibliography entries include:   a - the page numbers where the book or article is cited in the document. b - a few lines of review of the cited work.   It is a kind of mix between bibliography, index and review.  Are there stable LaTeX packages/BibTeX styles to do (a) and (b) ?  EDIT: I wrote (b) initially as "comments about the work cited". It could be understood as "gathering comments made in the book about the work and reproducing them in the bibliography".  This is not what I meant but this could be something useful for others. Question list on profile page not vertically aligned There's something wrong with the vertical alignment on the :   (click to enlarge)  On the , which uses a similar list but without the Favorite column, the vertical alignment is correct.  (Tested in the latest Firefox, Safari and Chrome on macOS Catalina.) I am a little bit confused by early stopping and in particular by how it can be inserted inside a CV framework. As far as I understand, I can fix the optimal number of epochs (for NN, or number of trees for XGB) by early stopping, that is:   pick a validation set, train with increasing number of epochs until a predefined metric evaluated on the validation set starts worsening that is the optimal number of epochs to prevent overfitting   and that's fine. But then I would like to insert this early stopping framework inside a CV framework: Suppose I have a model with 10 hyperparameters I want to fix via CV. And suppose that there is an eleventh hyperparameter, the number of epochs. My feeling is that one can do like this:   create the K resampled folds, for each of which you have a training and validation set choose a suitable grid for your 10 hyperparameters for each point on the grid train your model in each fold with early stopping, that is use the validation set of the fold to keep track of the preferred metric and stop when it gets worse take the mean of the K validation metric choose the point of the grid (i.e. the set of hyperparameters) that gives the best metric   Questions:   What number of epochs should I choose as optimal? in each of the K folds I have, in general, a different number of stopping epochs.  seems to suggest they take the mean of the K stopping epochs. Is this right? Is it actually a "fair" practice to use the validation metric coming from the early stopping as a proxy of the out-of-sample metric? As  in section 3.4.5, maybe the best thing to do would be:     ...if you want to do early stopping, then in each fold you should take your training set and split it again, holding out a small early-stopping-set to guide the early stopping, and then evaluate the model on the validation set of that fold.   But this seems to me a really intricate process...   Unfortunately, I wasn't able to find references where this issue is presented in a clear and transparent form. The limit of a convergent Gaussian random variable sequence is still a Gaussian random variable I'm trying to prove this conclusion but have some problems with one of the steps.  Assume $X_1,\ldots,X_n,\ldots$ is a sequence of Gaussian random variables, converging almost surely to $X$, prove that $X$ is Gaussian.  We use characteristics function here. Since $|\phi_{X_n}(t)|\leq 1$, by dominated convergent theorem, we have for any $t$  $$ \lim_{n\rightarrow\infty}e^{it\mu_n-t^2\sigma_n^2/2}=\lim_{n\rightarrow \infty}\phi_{X_n}(t) = \lim_{n\rightarrow \infty}\mathbb{E}\left[e^{itX_n}\right] = \mathbb{E}\left[e^{itX}\right] = \phi_X(t) $$  this is the step that I cannot figure out: $e^{it\mu_n-t^2\sigma_n^2/2}$ converges for any $t$ if and only if $\mu_n$ and $\sigma_n$ converges.   Let $\mu=\lim_n \mu_n$, and $\sigma=\lim_n\sigma_n$, then $\phi_X(t)=e^{it\mu-t^2\sigma^2/2}$, which proves that $X$ is a Gaussian random variable.  Why can we get that $\mu_n$ and $\sigma_n$ converge? This looks intuitive for me, but I cannot make a rigorous prove. The collection of all subsets of $\mathbb{Z}$ is uncountable, due to   But how can I prove that the collection of all finite subsets of $\mathbb{Z}$ is countable? Java Swing: Displaying images from within a Jar When running a Java app from eclipse my ImageIcon shows up just fine.  But after creating a jar the path to the image obviously gets screwed up.  Is there a way to extract an image from the jar at runtime so I can then open it up?  Or, is there a better way to do this?  I'd like to distribute a single jar file if possible. What is the safest, quick way to defrost chicken? Microwave? Running water over it? How to reverse the pagination numbers of an archive? I have archive pages that each contain titles and excerpts from 10 blog entries. Both entries and archive pages are in reverse chronological order:   when a new blog entry is written its title and excerpt go to the top of the front page; when you are on one page and you click through to "Next page", you get the titles and excerpts for the 10 previous blog entries.   This is pretty standard for blogs.  But the archive pages are numbered by default in the same order. Thus Page 1 contains excerpts from the most recent 10 entries, Page 2 contains excerpts from the next 10 most recent, etc.  To be clear: at the moment, "Next page" refers to the page with the next higher number. Thus the front page, which contains excerpts from the most recent entry and the nine next most recent entries, is labelled Page 1, and the 10 entries posted before those 10 entries are on Page 2.  I need the page-numbering the other way round, namely in direct chronological order, so that for example if there are 97 entries then   entries 28-37 would be excerpted on Page 4, and the PREVIOUS page from there, containing excerpts from entries 18-27, would be called page 3.   How can I achieve this, whether by amending functions.php in the child theme (preferably), by writing a "Snippet" (next most preferred), or by amending archive.php in the Astra parent theme directly (least preferred, because of possible update problems)?  Edit  The following isn't a solution but it may be part of one. This re-numbers pages into direct chronological order, but unfortunately it also reverses the order in which they are shown (from reverse chronological to direct chronological). So it causes the front archive paget to contain excerpts from the earliest posts rather than the latest ones!  &lt;?php  add_filter('pre_get_posts', 'posts_by_forward_date');  function posts_by_forward_date($query) {   if(is_archive() || is_home()) {     $query-&gt;set('order', 'ASC');   } } ?&gt; How can you tell when a roast is done? How can you tell when a roast is done?  How long should they roast for? Having problems with listings and UTF-8. Can it be fixed? Updating VS Code in ubuntu 18.04 Is the Nintendo 3DS region-locked? I am thinking of buying a 3DS when the price drop comes into place in America, however I live in Australia. Will Australian 3DS games work on a North American 3DS? How do Horcruxes work? A few questions regarding the Horcruxes.   Had Voldemort actually succeeded in using a Horcrux, would he come back the same age (biologically and/or aesthetically) he was when he made the Horcrux, or the age he would biologically be if he had never died (half died)? If Harry was a Horcrux, then in the graveyard, when Wormtail added Harry's blood to the potion to bring Voldemort back, didn't that technically use up the Horcrux inside of Harry? So in Deathly Hallows when Voldemort kills Harry, shouldn't Harry have actually died rather than just have the Horcrux inside him destroyed, seeing as it was technically used in the Goblet of Fire? How could I retrieve the exact duplicate value from conditionally formatted list that highlight duplicates? I have imported a webpage table in to Google Sheets. It frequently being updated. A series of calculations has been conducted on the sheet named Shawn Of the link spreadsheet.  I have filtered the my desired results into the Calculation sheet of that linked document... which is in columns A5:A. I then applied =ARRAYFORMULA(if(A5:A200=&quot;&quot;,,A5:A200*{12,13,37,101,111})) in columns B5. The Results of the formula extends from B5:F. This results from a5:F was subsequently conditionally formatted to highlighted duplicates in the aforementioned, i.e. a5:f using the lists of values in K5:K and I5:5. In Columns A5:F, is it possible to generate/place values in the range A5:f with matching name of states and aligned values in J5:K and H5:I? I'm considering re-designing my personal website to promote my web services in my local area.  My issue is whether to do a one page website with a scroll-to navigation system. What effect does this have on SEO. As i understand it, you set stuff like h1's and meta description on specific page content. How does this work when all of your different content is on one page? I want to write batch or something, that will write output of top into a file on login.  I did top &gt;&gt; output-file, but it contains some strange character!  Can somebody give a simple tutorial about how to write batch file in Linux? Continuous versus differentiable A function is "differentiable" if it has a derivative. A function is "continuous" if it has no sudden jumps in it.  Until today, I thought these were merely two equivalent definitions of the same concept. But I've read some stuff today which seems to be claiming that this is not the case.  The obvious next question is "why?" Apparently somebody has already asked:    Several answers were given, but I don't understand any of them. In particular, Wikipedia and one of the replies above both claim that $|x|$ has no derivative. Can anyone explain this extremely unexpected result?  Edit: Apparently some people dislike the fact that this is non-obvious to me. To be clear: I am not saying that the result is untrue. (I'm sure many great mathematicians have analysed the question very carefuly and are quite sure of the answer.) I am saying that it is extremely perplexing. (As a general rule, mathematics has a habit of doing that. Which is one of the reasons why we demand proof of everything.)  In particular, can anyone explain precisely why the derivative of $|x|$ at zero is not simply zero? After all, the function is neither increasing nor decreasing, which ought to mean the derivative is zero. Alternatively, the expression  $$\frac{|x + a| - |x - a|}{a}$$  becomes closer and closer to zero as $a$ becomes closer to zero when $x=0$. (In fact, it is exactly zero for all $a$!) Is that not how derivatives work?  Several answers have suggested that the derivative is not defined here "because there would be a jump in the derivative at that point". This seems to assert that a continuous function must never have a discontinuous derivative; I'm not convinced that this is the case. Can anyone confirm or refuse this argument? I've noticed in the last couple of days that there have been a few occasions when there's been a sudden surge of questions in the SO "Reopen" review queue.  Normally there's either no questions at all to reopen or at most three or four, and that's still the case, except that for the last couple of days I've gone to the review page and seen about fifty-odd questions in the queue, where just moments before there had been none.  I've gone through the reviews and the questions themselves seem reasonably legitimate (including the occasional audit), so I'm not questioning that... it just seems odd that there would be so many more than usual all of a sudden, and that they'd all appear at once.  Anyone got any insights, or should I just chalk this down as "one of those things"?