Grand Central Dispatch async vs sync
Difference between DispatchQueue.main.async and DispatchQueue.main.sync
In Helgason, "Differential Geometry, Lie Groups and Symmetric Spaces"  we have the formula for the exterior derivative  $(p+1)d\omega(X_{1}, \ldots X_{p+1})=\Sigma_{i=1}^{p+1} (-1)^{i+1} X_{i} \cdot \omega(X_{1}, \ldots , \hat{X_{i}}, \ldots X_{p+1})+\Sigma_{i&lt;j} (-1)^{i+j}\omega([X_{i}, X_{j}], X_{1}, \ldots , \hat{X_{i}}, \ldots \hat{X_{j}}, \ldots , X_{p+1})$  but in other sources on-line they have the same formula without the factor of $p+1$ on the left-hand side.  Are there two different definitions of the exterior derivative, or is there an error in Helgason? How do you do a deep copy of an object in .NET? Determining if a game is CPU- or GPU-limited What is a reliable, but not too time-consuming way to determine if a certain game is limited by the graphics card or by the processor speed?  I have some preconceptions about whether I'm mostly GPU or CPU limited, but I'd like to verify if I'm right about that. I have some ideas how I would go around and test that but performing accurate benchmarks is notoriously tricky and I don't have much experience with it.   So I'm wondering what would be an easy way to determine the bottleneck, having only one computer with a certain configuration available? What tools would I use for that purpose?  It would also be interesting to determine if the amount of VRAM on my graphics card is a limiting factor. What does "Baking" mean? I want to make some cool items for Dota 2 and I'm reading a guide. There are some tips about baking  etc. but I can't use them, because I don't even know what baking means. Can somebody explain this, please?  Thanks for all answers. `--no-install-recommends` only specified packages I want to install xfce4-goodies but I don't want Midori Browser. With --no-install-recommends I don't know how to specify only Midori. I want the rest of packages. How to do that? Thanks! I may have missed it with the 3D, but I could have sworn I saw what I suspect was a lady Dwarf or two running from the Erebor in the beginning of the Hobbit, but they didn't seem bearded.    If dwarf women aren't bearded, then was Aragorn just kidding in the Two Towers (movie) when he intimated that they all had beards?    It's also stated by Tolkien in appendix A to The Lord of the Rings that female dwarves appear identical to males and we can assume they are also born with beards, just like their male counterparts. $ d_1,d_2\mid n\iff {\rm lcm}(d_1,d_2)\mid n\ $ [LCM Universal Property] 14 months ago, an  supplement was published that discussed how the ranger described in the Player's Handbook was under powered. These rules reimagined the ranger's abilities, and suggested that an official version would be released later.     Finally, we come to implementation. If this iteration of the ranger, or a future revision of it, grades high enough, our plan is to present it as a revised ranger in a future D&amp;D sourcebook.   Does that Sourcebook exist yet? If not, have the devs given an update or told us their intentions? In a table, how can I draw a horizontal line that goes only through some of the cells? I mean a line like the one in the Foo and in the Bar area of this table:  +----+-----+ |Foo |1 |2 | |    |1 |2 | |    +--+--+ |    |1 |2 | |    |1 |2 | +----+-----+ |Bar |1 |2 | |    |1 |2 | |    +--+--+ |    |1 |2 | |    |1 |2 | +----+--+--+ I want to show the IP address like below  lo : 127.0.0.1  eth0 : 192.168.5.123 eth1 : 192.172.0.212 wlan0 : 10.1.0.124   I'm able to print all IP address by ifconfig | awk '/inet addr/{print substr($2,6)}'. But it is only printing the IPs. Every system have their own interface names and addresses. So my script has to show their interfaces with respect to IP addresses. I have opened Disks program today and noticed that there is FAILING in the Assessment column for the SMART status.     What does this error mean? Is it serious problem?  I have Lenovo G50-45 laptop, disk is SEAGATE ST1000LM014-SSHD-8GB(LVD3) 1TB SSHD with 8GB NAND Flash (original disk in this latop).  Update 2017-09-24:  The disk has died yesterday. 1 year and 3 months have passed since 1st hint of problem. About 4 months ago I had few issues with it not booting, but I was able to make another clean install. Since yesterday the disk is non-responsive. As this was long expected I had backup of all important data.(!) The disk was about 2 years old, so that was quite premature death. (p.236)  has a proof that the equation $e^z-z=0$ has infinitely many complex solutions:    I'm curious if there are any particularly elegant ways to see this, other than that given in the text. Prove norm doesn't come from inner product. Please help me prove this. I'm not sure how to apply the parallelogram law to the norm. Can you add new statements to Python's syntax? Can you add new statements (like print, raise, with) to Python's syntax?  Say, to allow..  mystatement "Something"   Or,  new_if True:     print "example"   Not so much if you should, but rather if it's possible (short of modifying the python interpreters code) If I look through the microwave window I can see through, which means visible radiation can get out. We know also that there is a mesh on the microwave window which prevents microwave from coming out.  My question is how does this work? how come making stripes or mesh of metals can attenuate microwave radiation yet allow visible radiation?  Looks like an electrodynamics problem to me with periodic boundary conditions (because of the partitions on the microwave oven window). Is it discussed in any textbook? I cant use lhopital's rule here is my attempt:  Limit of $(\frac{n^{2}-2n+1}{n^{2}-4n+2})^{n}$ =$e^{\lim_{n\to \infty} n\times \ln(\frac{1 -2-n +\frac{1}{n^{2}}}{1 -\frac{4}{n} +\frac{2}{n^{2}}})}$ I got stuck here GRUB and LILO both fail to install to NVMe hard disk when installing Debian Finding places to play Magic the Gathering games A friend of mine recently got MTG for the XBox and is talking us into getting real cards.  I'm all up for starting but I dread the idea of playing the same two people over and over with no change epically since one of them is over competitive and exploits every loophole he can to win.  Does anyone know of any a reliable (not just google it) way to find places where people play MTG? Proving the Cauchy-Schwarz inequality by induction Mark a comment as the answer to a question