How do you move files modified after a specific date (say 7 days for example) to another directory? I clumsily tried sending the output of  ls -t | head -n XX   But learnt recently that it isn't a good idea to parse ls.
With the ls command, is it possible to show only the files created after a specific date, hour...?  I'm asking it because I have a directory with thousand of files.  I want so see all files that were created since yesterday.   I use ls -ltr but I have to wait to see all files...  There is an equivalent of DIRECTORY/SINCE=date from OpenVMS ?
Where can I see how many posts have I edited? I have two $2\times 2$ matrices, $A$ and $B$, with the same determinant. I want to know if they are similar or not.  I solved this by using a matrix called $S$: $$\left(\begin{array}{cc} a&amp; b\\ c&amp; d \end{array}\right)$$ and its inverse in terms of $a$, $b$, $c$, and $d$, then showing that there was no solution to $A = SBS^{-1}$. That worked fine, but what will I do if I have $3\times 3$ or $9\times 9$ matrices? I can't possibly make system that complex and solve it.  How can I know if any two matrices represent the "same" linear transformation with different bases?  That is, how can I find $S$ that change of basis matrix?  I tried making $A$ and $B$ into linear transformations... but without the bases for the linear transformations I had no way of comparing them.  (I have read that similar matrices will have the same eigenvalues... and the same "trace" --but my class has not studied these yet. Also, it may be the case that some matrices with the same trace and eigenvalues are not similar so this will not solve my problem.)  I have one idea. Maybe if I look at the reduced col. and row echelon forms that will tell me something about the basis for the linear transformation? I'm not really certain how this would work though? Please help. Why do some questions not start with an auxiliary verb? When I learned English, my teachers told me that all questions must have an auxiliary verb at the beginning, just like Are you mad? or Is she playing? do.  But when watching some movies or talking with people who speak English, they just ask using things like You mad? and She’s playing?   Of course, the kind of intonation let me know they are asking a question, but why this happen? We're given a sequence defined by the recursive relation: $$a_n = \sqrt{a_{n-1}a_{n-2}}$$  $a_1$ and $a_2$ are positive constants. We have to show the following:   The sequences $\{ b_n \} = \{ a_{2n-1} \}$ and $\{ c_n \} = \{ a_{2n} \} $ are monotonic, and if one is increasing, the other is decreasing. The limit of the sequence $\{ a_n \} $ is $ \left(a_1a_2^2\right)^{\frac13} $     Now, I have proved the first part. Besides that, I have also proved a few other things:  If $a_1 &gt; a_2$, then:  a. $ \{ b_n \} $ decreases, and $ \{ c_n \} $ increases.  b. $ c_n &lt; b_n $  If $a_1 &lt; a_2$, we just flip $\{ b_n \}$ and $\{c_n\}$  Besides, I have also shown that both the sequences : $\{b_n\}$ and $\{ c_n\}$ have the same limit. What I don't know, is how to evaluate the limit. Remote Desktop Settings Missing I'm trying to setup remote connection to my Windows 10 machine. During the setup I noticed that my installation is missing some settings all the tutorials have. Can anyone tell me why I'm stupid and what I should do? Below you can find a screenshot of what I'm talking about. The first image is how it should be. The second picture is a screenshot on my machine.      Edit: After popular request, my windows version: I've upgraded from 12.04 to 14.04 via command-line when my system froze, had to do REISUB and dpkg --configure -a to recover from crash after rebooting.  Now everything seems to work except automatically mounting external thumb drives and external hard disk drives. After plugging in said drives, they fail to show up on the left pane and remains unmounted. I can see the device if I run lsusb and fdisk though, so it's possibly to manually mount it but I'd rather resolve why it's not automatically mounting. Reference for the subgroup structure of $\rm{PSL}_2(q)$ What mechanism is responsible for the creation of these dunes on Comet 67P/Churyumov-Gerasimenko?  The following high resolution picture from ESA's Rosetta mission shows the dunes:       At a distance of 7.8 km from the surface, the image scale is about   66.5 cm/pixel, so each 1024 x 1024 pixel frame is about 680 m across (although if we assume the furthest point away is an additional ~1 km   further from the centre, the image scale is about 92 cm/pixel).   So the scale of the dunes is on the order of tens of meters along the crest. And each crest are probably just a few meters apart. Solving a six-degree polynomial of the form $ax^6+bx^3+g$. I read that it is not always possible to solve but from Wikipedia:      Some sixth degree equations, such as $ax^6 + dx^3 + g = 0$, can be solved   by factorizing into radicals, but other sextics cannot.   So how do you solve this? I've stumbled upon this equation where; $a = n^2$, $d=m^2n-2p^2$, and $g=m^4$. Where the $a,d,g$ corresponds to the above mentioned sextic-equation and $m,n,p$ are input variables. I apologize for that ton of variables in use, might cause some confusion. Is this possible using Galois Theory or by any other means? Ubuntu does not offers me "install alongside Windows" Any of the partitions makes in Windows was not recognised by Ubuntu, or Zorin OS, or LinuxMint. It's like a blank hard disc, 250 gb free. I'm a new Linux user, but what confuses me is that I was able to install Ubuntu alongside Windows on my laptop with no problems, but on PC... no way! Give $\ker(\phi)$  for $\phi: \mathbb{Z} \to \mathbb{Z_7}$ such that $\phi(1) = 4$  So the generator of $\mathbb{Z}$ maps to $4$ and $\langle 4 \rangle = \{0,1,2,3,4,5,6\}$ so it has order seven.  so $\ker(\phi) = 7\mathbb{Z}$ because every seventh element will map to the identity under the given map. Is that the correct reasoning? It would be nice to  for .  As it is, SE kind of stands out (in a not cool way): Control Cycles/Eevee material nodes and material properties using python? Why is the light in an airplane turned off during take off and landing? Make all i.stack.imgur.com links protocol-relative Stack Overflow has HTTPS in some places! However, this breaks most existing image links. Could those be made protocol-relative, or react to the requesting protocol, or just always use HTTPS?  The same applies to .sponsor-tag-img. Determine the smallest positive value of x(in degrees) for which: $\tan(x+100^{\circ}) = \tan(x+50^{\circ})\tan (x)\tan(x-50^{\circ})$ I've been programming in Java for a while and just got thrown onto a project that's written entirely in C#.  I'm trying to come up to speed in C#, and noticed enums used in several places in my new project, but at first glance, C#'s enums seem to be more simplistic than the Java 1.5+ implementation.  Can anyone enumerate the differences between C# and Java enums, and how to overcome the differences?  (I don't want to start a language flame war, I just want to know how to do some things in C# that I used to do in Java).  For example, could someone post a C# counterpart to Sun's famous Planet enum example?  public enum Planet {   MERCURY (3.303e+23, 2.4397e6),   VENUS   (4.869e+24, 6.0518e6),   EARTH   (5.976e+24, 6.37814e6),   MARS    (6.421e+23, 3.3972e6),   JUPITER (1.9e+27,   7.1492e7),   SATURN  (5.688e+26, 6.0268e7),   URANUS  (8.686e+25, 2.5559e7),   NEPTUNE (1.024e+26, 2.4746e7),   PLUTO   (1.27e+22,  1.137e6);    private final double mass;   // in kilograms   private final double radius; // in meters   Planet(double mass, double radius) {       this.mass = mass;       this.radius = radius;   }   public double mass()   { return mass; }   public double radius() { return radius; }    // universal gravitational constant  (m3 kg-1 s-2)   public static final double G = 6.67300E-11;    public double surfaceGravity() {       return G * mass / (radius * radius);   }   public double surfaceWeight(double otherMass) {       return otherMass * surfaceGravity();   } }  // Example usage (slight modification of Sun's example): public static void main(String[] args) {     Planet pEarth = Planet.EARTH;     double earthRadius = pEarth.radius(); // Just threw it in to show usage      // Argument passed in is earth Weight.  Calculate weight on each planet:     double earthWeight = Double.parseDouble(args[0]);     double mass = earthWeight/pEarth.surfaceGravity();     for (Planet p : Planet.values())        System.out.printf("Your weight on %s is %f%n",                          p, p.surfaceWeight(mass)); }  // Example output: $ java Planet 175 Your weight on MERCURY is 66.107583 Your weight on VENUS is 158.374842 [etc ...] I am registered on about 80 SE sites, am an "avid user"(>200 rep) on about 30, and a modest user (103-199 rep) on about 20 more.  Once when I tried to ask a question on Open Data (my "new user" site), the "systemwide" 40 minute rate limit kicked in. So I asked on meta , given that my previous post on the site was days ago. So a mod commented by telling me about the systemwide post rule and asking me if I had just come from another site. I said, yes, History (my best site, 40K rep.)  I can see why I would be rate limited on Open Data. I can understand that I would be rate limited if I had come from say, Open Source, another site where I'm a new user. But did the system "rate limit" me as a new user on one site, based on my activity on History, an "established" site?  Also, about the one day new user rate limit after a question is downvoted: Suppose a question on the previous site receives two upvotes and one downvote (net of one upvote). Is that a different situation than receiving one down downvote and no upvotes? Or does the downvote count in both cases, including the one where there were offsetting upvotes? How about if the downvoted question on the previous site was deleted?  I don't have this problem when going from one "established" (greater than 125 rep) site to another. I understand why a person would be "rate limited" going from one new site to another; SE wants people to ask questions 40 minutes apart on their new sites. In my case, I was blocked when I left an "established" site (my best) to go to a new site, which is almost the same as going to a new site de novo.  Why would this be? Or can't the system tell that my "first" site was an established site? Would I have been similarly rate limited if I went first to the "new" site, and 39 minutes later to the established site? Or does the rate limit apply only when the "destination" site is the new site?  Put another way, there are four permutations of established and new sites: 1) established to established 2) new to new 3) established to new and 4) new to established. The block doesn't apply in the first case, does apply in the second case, and apparently applies in the third. What about the fourth? And why? Because it is not "uniform" across sites in the four cases.   Edit: Unlike the other question, this one is not about the general rule. It is about the "special case" described in the paragraph above. Multiple file upload in php How to set static IP address?