How should I make a deep copy of a Dictionary?
What is the best way to clone/deep copy a .NET generic Dictionary?
Are +1/+1 counters different from +1/+1 effects? Unsure whether to use "enquire" or "inquire" Is it possible to make a simple query to count how many records I have in a determined period of time like a year, month, or day, having a TIMESTAMP field, like:   SELECT COUNT(id) FROM stats WHERE record_date.YEAR = 2009 GROUP BY record_date.YEAR   Or even:  SELECT COUNT(id) FROM stats GROUP BY record_date.YEAR, record_date.MONTH   To have a monthly statistic.   Thanks! Slovak (and Czech) babel gives problems with cmidrule and cline I tried to use the Slovak language with the booktabs package.    Let's see a couple of cases.   slovak is included in the options to babel     \usepackage[english,slovak]{babel}   or    \usepackage[slovak,english]{babel}   or    \usepackage[slovak]{babel}`  "slovak" is NOT included in the options to babel  \usepackage[english]{babel}    Similarly two cases for \cmidrule  A. \cmidrule{2-3} is included in the table    B. \cmidrule{2-3} is NOT included in the table    If both (slovak+\cmidrule) are included (case 1A), then following error occurrs  Paragraph ended before \@@@cmidrule was complete   (and a lot of other errors)  In the other cases (1B, 2A and 2B) (NO slovak or NO \cmidrule), then pdflatex is succesful  Does anybody know why 1A is wrong?    And how to use slovak and \cmidrule together (case 1A)?  \documentclass[10pt]{book} \usepackage[english,slovak]{babel} \usepackage{booktabs}  \begin{document}  \begin{tabular}{ccc} A &amp; B &amp; C \\ %\cmidrule{2-3} A &amp; B &amp; C \\ \end{tabular}  \end{document}   I have Win7, TeXstudio 2.5.2 Is it true that an ideal is primary iff its radical is prime? Why does increasing the number of features reduce performance? I'm trying to gain an intuition as to why increasing the number of features could reduce performance.  I'm currently using an LDA classifier which performs better bivariately among certain features but worse when looking at more features.  My classification accuracy is performed using a stratified 10-fold xval.    Is there a simple case of when a classifier would work better univariately than bivaraiately to gain a somewhat physical or spatial intuition of what is happening in these higher dimensions? How to customize the Ubuntu Live CD? Biblatex-apa style is missing a comma in the references. why? I have been trying to solve this problems for hours, but there is no solution in sight.  Until a few weeks ago, my biblatex-apa style was working like a charm. Although, after installing the updates and Biber, the reference section became a problem. It should display a journal article by two authors with a comma after the first author, but it doesn't:     Weber, M. &amp; Ruch, W. (2012). The role of character strengths in adolescent romantic relationships: An initial study on partner selection and mates’ life satisfaction. Journal of adolescence, 35(6), 1537–1546. doi:10.1016/j.adolescence.2012.06.002   it should look like this:     Weber, M., &amp; Ruch, W. (2012). The role of character strengths in adolescent romantic relationships: An initial study on partner selection and mates’ life satisfaction. Journal of adolescence, 35(6), 1537–1546. doi:10.1016/j.adolescence.2012.06.002   This is how my document looks like:   \documentclass[12pt, onecolumn]{apa6}   \usepackage[utf8]{inputenc} \usepackage[american]{babel} \usepackage{csquotes} \usepackage[style= apa, backend=biber]{biblatex} \bibliography{testbib} \DeclareLanguageMapping{american}{american-apa}   \begin{document}  Some text \parencite{Weber2012}.  \printbibliography \end{document}   And the BibTeX file:  @article{Weber2012, abstract = {}, author = {Weber, M. and Ruch, W.}, doi = {10.1016/j.adolescence.2012.06.002}, file = {}, issn = {1095-9254}, journal = {Journal of adolescence}, number = {6}, pages = {1537--1546}, pmid = {22749517}, publisher = {Elsevier Ltd}, title = {{The role of character strengths in adolescent romantic relationships: An initial        study on partner selection and mates' life satisfaction.}}, url = {http://www.ncbi.nlm.nih.gov/pubmed/22749517}, volume = {35}, year = {2012} }    I have tried various things so far, but none of it helped: e.g,   \renewcommand*{\finalnamedelim}{ \finalandcomma}   or  \renewcommand\finalandcomma{\addcomma}   Even in the biblatex manual, the reference examples of two authors is without the comma (it works for three or more authors). There should be a comma, according to . Why is that comma not there? And how could I insert that into my references? If the original question is "What time is it?" and I want to communicate it to another person, are these Embedded Questions OK?        I don't know what time is it.       or        I didn't know what time was it. (if communicated later) half sine and half cosine quaternions Is there ever a right time to upgrade to full frame camera body? Context  I've been shooting with an a6000 (APS_C mirrorless) and I plan to move on up to full frame, preferably mirrorless as well. I'm debating on when to upgrade, and probably don't plan to buy until next year.  I know I'll need to buy new full frame lens.  Question  Is there a "right" time to buy camera bodies, both mirrorless in my case as well as DSLRs? (I've seen the a7rII and like it but there might also be an a9 looming.) I feel that this is like smartphones in which the best time to buy is now as you might always be waiting until the next upgrade.   Related, are full frame bodies discounted during the holiday season or is that limited only to entry level bodies and older full frame bodies?  Related I'm attempting to cut a hole in a plane. I added a cylinder object, added the Boolean modifier to the plane, selected "cylinder" and "Difference", but no hole is made. The lower half of the cylinder just highlights, moving/deleting the cylinder reveals a hole-less plane.      How can i cut a hole in the plane? Why didn't Gimli know Moria had fallen? If $a$ and $b$ are two roots of $x^4 + x^3 - 1 = 0$ prove that $ab$ is a root of $x^6 + x^4 + x^3 - x^2 - 1$. Is there an old, rarely used word which means "an archaic word"? Handle either a list or single integer as an argument Proving the so-called "Well Ordering Principle" Is there anything wrong with the following proof?  Theorem. Every non-empty subset $B \subset\mathbb{N}$ has a least member.  Proof. Assume not. Then, of necessity, we'd have to have $B=\varnothing$, for if $B$ contained even one $b\in\mathbb{N}$, then that $b$ would satisfy $b=min(B). $ Contradiction, end proof.  I get the sense there is something wrong here, but I can't seem to define exactly what. Also, is there a context where one can simply take this principle as an axiom, and not have to prove it? After all, it is extremely intuitive. Thanks. Transit Visa in Hong Kong for 15 hour layover between India and USA? We are (2) Indian nation and travelling from India to USA via Hong Kong airport and about 15 hours layover in Hong Kong airport. Do we need a transit visa even if only changing planes? And can we apply in Hong Kong Airport? On the photos where the lens flare is present, my Nikon D7000 is drawing strange labyrinth-looking artifacts. Here's an example.  The first image is a screenshot of a little part of the original photo zoomed 2:1 in Lightroom.  The second image is the same photo with Lightroom's contrast, clarity and sharpening set to the maximum to make the labyrinth pattern more visible.      This affects only some of the photos presenting lens flare. Here, for instance, the lens flare is present and light conditions are very close to the first photo, but there is no labyrinth pattern, only usual noise (screenshot of a part of a photo at 1:1 with contrast, clarity and sharpening set to the maximum):    Notes:   I can see this pattern only on some of the photos when the sun is in the frame or nearly in the frame. It is present with any lens I tested. The actual photo was shot at f/8, ISO 200, 1/640 s. I've seen this pattern in photos shot at ISO 100 as well. The photo is in RAW format, so this is not a JPEG artifact.   What is that? How do I avoid it? The divisibility rule for $3$ is well-known: if you add up the digits of $n$ and the sum is divisible by $3$, then $n$ is divisible by three.  This is quite helpful for determining if really large numbers are multiples of three, because we can recursively apply this rule:  $$1212582439 \rightarrow 37 \rightarrow 10\rightarrow 1 \implies 3\not\mid 1212582439$$ $$124524 \rightarrow 18 \rightarrow 9 \implies 3\mid 124524$$  This works for as many numbers as I've tried.  However, I'm not sure how this may be proven.  Thus, my question is:     Given a positive integer $n$ and that $3\mid\text{(the sum of the digits of $n$)}$, how may we prove that $3\mid n$?