What is my firmware, software, and operating system?
Firmware vs. Software
Can a 64-bit OS run as a guest on a 64-bit VirtualBox host? Is it possible to run a 64-bit OS as a guest on a 64-bit machine with VirtualBox? I'm guessing it should be, but I'd like to make sure.  Do some virtualization technologies allow a single guest machine to use multiple cores? I guess it should be possible, but my VirtualBox open-source edition doesn't seem to do it. How can I increment a date by one day in Java? Removing overlapping part of polygons using QGIS? Here is what I'd like to achieve in QGIS.   Is there a processing tool to remove the overlapping part of polygons?    It is also very important that they do not get merged during the process and that they keep their original attributes since I need to work with them afterwards. Write18: capturing shell (script) output as command/variable? Let's say I compile the following file with pdflatex -shell-escape test.tex:   \documentclass{minimal}  \begin{document}  File listing is:  \immediate\write18{ls /usr}  \end{document}   This will send the output of the command ls /usr to report/log of pdflatex (primarily to stdout).   There are then two cases I'd like to utilize:    The output of ls /usr being included directly in the document (LaTeX stream). The output of ls /usr becoming the contents of a \newcommand (by this I mean, that I'd like the script to be executed when the \newcommand is executed first - and upon subsequent calls to the new command, the shell code should not be executed anew).    I have read through , but I'm not sure if this "pipe input" can be applied to \newcommand.   I have also read through  - and it seems that Tex' file I/O should be used; but I'm quite disliking the fact that I'd still have to redirect the script output (actually, in this case, the ls /usr output) to a file, and then read it in, to have it as contents of a command.   So, is there an easier way to achieve what I'd want (hopefully, illustrated through an example based on the above code)?     EDIT: Ehm, I should have asked one more question earlier :) I'll try with an edit here, although it will probably get missed .. :)   I originally asked for a \newcommand that will execute shell code only upon its definition (i.e., in a sense it is "cached"); and the answer from @egreg does exactly that. But then - would it be possible to have a different \newcommand definition, such that each time this newcommand is called, the shell command is executed anew? I.e. executing something like \@@input|"cat tempfile" (which cannot be executed as such), where tempfile changes between calls? Books for starting with analysis I am interested in self-studying real analysis, and I was wondering which textbook I should pick up. I know all high school mathematics, I have read  (I did most of the exercises).  I have completed a computational calculus course which covered everything up to and including integration by parts (including the substitution method and Riemann sums) I am currently considering:    From what I have heard this is not very well suited for self-study and that while the exercises are extremely difficult, if you take the time they are worth the effort.    I have heard that while Spivak explains proofs in much more detail than Principles, it doesn't cover all of the material in the latter.    I don't know much about this. I have only seen some comments saying that it is an excellent introduction to analysis.    Extra clarification edit: I would prefer a book not to ''dumb down'' the material, something that would not hold my hand through every step, something that would force me to fill in the gaps myself instead of explaining every single step. That is why I am currently leaning towards Rudin, but before I decide I would still like some information on the book by Apostol. How to remove comma and "and" before institutional last author after compiling BibTeX I have the following BibTeX entry:  @article{pubmed18800157,     author = {Heng, T.S. and Painter, M.W. and Immunological Genome Project Consortium},     title = {The {I}mmunological {G}enome {P}roject: networks of gene expression in immune cells.},     journal = {Nat. Immunol.},     pages = {1091-1094},     volume = {9},     number ={10},     year = {2008}, }, %\bibliographystyle{unsrt}   When the bibliography is generated, it puts comma a the end of the author:   Notice the comma after M.W. Painter. Is there a way to remove it? Multiple "order by" in LINQ Why do single-author community wiki answers (or questions?) link to revisions, rather than to the author's profile? Possible Duplicate:             Looking at  , I noticed something peculiar: Community Wiki posts* with only one author have not one, but two different links to the revisions page.    Is this entirely necessary? When clicking on the author's name in this case, I entirely would expect to be brought to the author's profile, rather than to the (potentially one-item-long) revisions list.   *(maybe only answers? couldn't find any good single-author CW question references) In my custom Drupal 8 plug-in I perform such query:  $select = db_select('my_table', 'e'); $select-&gt;addField('e', 'field1');  $select-&gt;condition('field3', 'NULL', '!='); $select-&gt;condition('field4', array(11, 12, 31, 32, 33), 'IN');  $select-&gt;groupBy("e.field1"); $select-&gt;orderBy("e.field1"); $select-&gt;orderBy("e.field5"); $entries = $select-&gt;execute()-&gt;fetchAll(\PDO::FETCH_ASSOC);    And it works fine. It returns me all records grouped by field1 that meets the condition, orderered. But it returns only field1 column.  I wanted to get more columns, so I have added another $select-&gt;addField('e', 'field2'); just after first one:  $select = db_select('my_table', 'e'); $select-&gt;addField('e', 'field1'); $select-&gt;addField('e', 'field2');  $select-&gt;condition('field3', 'NULL', '!='); $select-&gt;condition('field4', array(11, 12, 31, 32, 33), 'IN');  $select-&gt;groupBy("e.field1"); $select-&gt;orderBy("e.field1"); $select-&gt;orderBy("e.field5"); $entries = $select-&gt;execute()-&gt;fetchAll(\PDO::FETCH_ASSOC);    This time I get error:     Drupal\Core\Database\DatabaseExceptionWrapper: SQLSTATE[42000]: Syntax error or access violation: 1055 Użyto 'my_database.e.field2' bez umieszczenia w group by:   Which means "my_database.e.field2 has been used without putting in into group by". But I don't want to group by every column I select.  Unfortunatelly Drupal 8 added ONLY_FULL_GROUP_BY :( Then, how can I use groupBy and select more then one column at the same time? Can my spouse receive an emergency UK visa to visit a funeral? I'm a British national. My grandmother just passed. My wife is Chinese. In general it's a major pain to get my wife a visa to visit the UK, we have never been before.  Is there any way to get an emergency visa to attend the funeral?  What sort of documents would we need? A site (or scraper) is copying content from Stack Exchange. What should I do? How can I distribute a native executable for a Python program? Lately all of my work has been in Python (and Ruby), and I'm in love with those two languages. There are many libraries for game development on Python but the problem I see is that many of those frameworks don't cover the "distribution" aspect of game creation. I'd like to code my game on Python (and any other pure Python extra libraries I need) and be able to distribute an executable for the main PC platforms (Windows, Mac and Linux).  Any options out there or what are the best combinations for this? (maybe pyglet + cx_freeze) Disable ssh password authentication by user Is it possible to enable ssh password authentication for one user on a system and disable it for an other.  If you add  ChallengeResponseAuthentication no PasswordAuthentication no UsePAM no   to /etc/ssh/sshd_config you disable it for all users  Adding it to ~/.ssh/config doesn't seem to work Can I disown my heir? Everything was perfect. I have a good and young ruler, who has passed on some good genes to his sons. I also had a lot of spare lands, so I could make my heir a duke and doubly count when he came of age.  My mistake was to marry him off to some scheming wench. I knew it would end like this, but her stats were just too great to resist!  Anyway, a few years down the road, and my trusty spy master lets me know that my beloved son is looking to usurp me. Not cool! I demand that he end the plot, and decide to see how this develops.  Shortly thereafter, he suddenly dies (not by my hand — likely the wife is the culprit). My second eldest son becomes my new heir and favourite, however all the titles are inherited by my clubfooted grand daughter aged two. Curses!  Now, what I really wanted, was to imprison and disown my traitorous son followed by swift justice of the axe. Not sure what my other vassals would think of that idea, but I had a just reason for imprisonment at least.  Option number two, is to start plotting for my dearly beloved grand daughters untimely demise, but I'm not sure how that would work out either.  The situation is this. I'm young (40ish) and well-liked. I have a new heir, but I'd prefer to keep my lands for myself and give him the ones of the previous heir — one duchy and two counties currently held by my grand daughter. The duchy can be revoked free of charge, as I hold a claim to it. She has no siblings. I am da King. I have limited crown authority, but can bump it up to medium if it suits me.    So my questions to you are as follows:   Is it possible to disown a son, considering I have just cause for imprisonment? An execution would of course settle the deal, but my other vassals would probably find me "cruel". Is it possible to plot against a character which is not yet of age? What would happen if she suddenly died with no heir? Would all her titles be returned to the king or duke (i.e. me)?   EPILOGUE I had savegames before and after, so I decided to test a few things.   I could imprison my quisling of a son. I could also seize all his titles and banish him from my lands, but he would remain an heir, even if he wasn't officially a prince. I guess I could have let him rot in jail, as it seems prisoners often die in custody, but it would be a risky bet. After the unfortunate death of my old heir, it seems some strange rules apply regarding the remaining titles. The dukal title I could simply revoke for free (although at a opinion penalty from the duchess). Should she die today, one of the counties would be inherited by her younger sister, and the other would be inherited by me.   I found this to be an interesting development: Turns out my new heirs wife suddenly died. Who did he marry, other than the same scheming hag who presumably killed off his brother, and made an attempt at me? By a suspicious coincidence, I died not very long after. Such is the effects of the deceitful and ambitious traits combined with a really dope intrigue stat. ;) Best approach to Windows Forms rolling log output in TextBox Not able to calculate sum of multiple column where file data in different format .csv I have a scenario where i want to calculate sum of column   SAL|CAL|TAG|VAL 12.11"|"1.1"|"2.1"|"1.1 13.11"|"1.1"|"2.2"|"2.2 14.11"|"1.1"|"2.4"|"2.4   My below code not giving output giving output as 0.00  I need output for this column CAL VAL  awk -F'|' '{T+=$2} END { printf "%.2f\n", T }' demo.txt   output :  6.7 5.7 Extracting Z data from point layer using ArcGIS Desktop? I have created a point layer with ~150 points. I have a DEM beneath it, which is where I have taken the X and Y values from.   Does anybody know how I can retrieve the Z values, without using the info button?  I am using ArcGIS Desktop 10. I have licences for the spatial analyst etc tools. Shader nodes are missing? Is there any way I can specify a standard or custom numeric format string to always output the sign, be it +ve or -ve (although what it should do for zero, I'm not sure!) Functional equation $f(r \cos \varphi)+f(r \sin \varphi)=f(r)$ Find all such monotonous function $f:[0,+\infty)\to \mathbb R$, such that for any real $r\ge0$ and $\varphi \in \left[\frac{\pi}6, \frac{\pi}4\right]$, $$f(r \cos \varphi)+f(r \sin \varphi)=f(r)\text.$$  My work so far:  If $\varphi \in \left[\frac{\pi}6, \frac{\pi}4\right]$ then $$\frac{\sqrt2}2\le\cos \varphi\le\frac{\sqrt3}2$$ $$\frac12\le\sin \varphi\le\frac{\sqrt2}2$$  If $r=0$ then $f(0)=0$  If $\varphi= \frac{\pi}{4}$ then $$f(r)=4f\left(\frac r2\right)$$  $f(x)=cx^2$ for $x\ge0$ and $c\in\mathbb R$