Eevee in render and in viewport, and material preview also not showing after updating my drivers
AMD GPU Material in "material preview mode" and "rendered mode", is entirely gray as background. Only outline is displayed
Why doesn't the Related question list show that questions are closed? Completing a 3x3 correlation matrix: two coefficients of the three given I was asked this question in an interview.  Lets say we have a correlation matrix of the form \begin{bmatrix}1&amp;0.6&amp;0.8\\0.6&amp;1&amp;\gamma\\0.8&amp;\gamma&amp;1\end{bmatrix}  I was asked to find the value of gamma, given this correlation matrix. I thought I could do something with the eigenvalues, since they should be all greater than or equal to 0.(Matrix should be positive semidefinite) - but I don't think this approach will yield the answer. I am missing a trick.  Could you please provide a hint to solve for the same? How to see the error messages when I get the white screen of death? I'm kind of curious what kinds of criteria other people go through when selecting the correct answer to their questions.  Here's what I consider when selecting the answer to my question:   Is the answer objective?  It's easy to pick out biased answers.  Usually they involve a statement along the lines of "x sucks, you should ALWAYS use y." Do other members seem to support the answer?  Has it gotten a significant number of +1 posts or has it been voted up a number of times? Is the answer the most thorough?  Does it have an example?   With that said, there are a couple of BAD reasons to choose an answer in my opinion:   The answer is what you want to hear.  My biggest pet peeve is when somebody asks what ostensibly appears to be a valid question, but is really just a thinly veiled attempt to get someone to agree with them.  Thus, the question usually ends up showing a certain bias.  And guess which answer gets selected?  The one that confirms that bias. Nobody posted a better answer.  If you don't see a good enough answer, don't select one.   I'm sure there are a few things I'm leaving out, plus some of what I've said may be arguable.  What is everyone else's take on this? I'm so puzzled about this:   $$a^{b^c} = a^{(b^c)} \neq (a^b)^c = a^{(bc)}.$$  Why isn't $a^{b^c}$ equal to $a^{(bc)}$? Why is $a^{b^c}$ instead equal to $a^{(b^c)}$? And how is it possible that $(a^b)^c = a^{(bc)}$?  My mind is pretty much exploding from trying to understand this. When electric dipole placed in non uniform electric field, what is the approach to calculate torque acting on it? Can it be zero? tcpdump shows traffic until I use a filter I have a server that is receiving traffic from a mirror port on a switch. The interface that is connected to this mirror port is in promisc mode. When I use just a plain catch all tcpdump on the interface, like   tcpdump -nn -i eth1   I see a ton of traffic.  I can even grep this for certain things like, say, port 443.  tcpdump -nn -i eth1 | grep 443   obviously this shows anything that has a 443 in it, not just port 443. I have visually inspected it and I do see stuff like this:  15:08:08.112550 IP 12.34.56.78.1430 &gt; 87.65.43.21.443: . ack 35124 win 32768   But I want just port 443 so...  tcpdump -nn -i eth1 port 443 ... 0 packets captured   Weird. I am not seeing any traffic when I use a filter. I have tried "ip port", "dst port", and a few other filters. I have also tried filtering by the IP instead of port. Nothing.  eth1      Link encap:Ethernet  HWaddr 00:24:81:A5:AD:7A             inet6 addr: fe80::224:81ff:fea5:ad7a/64 Scope:Link           UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1           RX packets:4114781478 errors:0 dropped:1 overruns:0 frame:0           TX packets:17 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:2240970313430 (2.0 TiB)  TX bytes:15155497 (14.4 MiB)           Interrupt:98 Memory:fa000000-fa012800    This interface has seen a ton of traffic. And my filter is valid, right? Why do I not see anything? What did the general public know about Darth Vader? When Darth Vader first becomes Palpatine's apprentice, very few know of his existence and connection to the Emperor: the members of the Trade Federation (whom he dispatches) and Yoda, Kenobi, Organa, and their associates are all that seem to know at the end of Episode III.  Ultimately, the Resistance would know about him as they would be fighting him, and Organa could have been able to inform them about his identity and the fact that he is a Force user. The military of the Empire would know of his existence, but even high-ranking members likely wouldn't know his past or identity. However, they would know about the fact that he is a Force user due to his tendency to use his "sorcerer's ways" to choke people.  So, how much would the general public have known about Vader? Would they have known him as just another military leader, or would they have known he was Palpatine's right-hand man? Would they have known about his ability to use the Force, and therefore the possibility that he was a Sith? Turn off close Facebook friend notification Defining the Product of Ideals How to deserialize a JSON String to Apex Prove that "injective function $f:X\to Y$ exists" and "surjective function $g:Y\to X$ exists" is logically equivalent. Prove that   injective function $f:X\to Y$ exists surjective function $g:Y\to X$ exists   is equivalent.$(x,y\neq \emptyset)$   My approach  First,prove left to right.  If injective function $f:X\to Y$ exists, a set A can be defined like this. $$A=\{f(x):x\in X\}$$ then it is sure that $A\subset Y$, and $|A|=|X|$  And, if we define function $g$ like $$g(y)=\begin{cases}x &amp; \text{if $y\in A$ and } f(x)=y,\\x_0&amp; \text{if }y\notin A.\end{cases}$$ ($x_0$ is a fixed element of $X$)  Then, $g$ is a surjective function, so surjective function $g:Y\to X$ exists.  Now,prove right to left.  If surjective function $g:Y\to X$ exists, $\forall x \in X$, we can select a element $y\in Y$ that $g(y)=x$, which is clear that we can pick a different $y\in Y$ for $\forall x \in X$  if we define function $f$ as $f(x)=\text{one element in Y that g(that element)=$x$}$, f is a injective function, so injective function $f:X\to Y$ exists.    But, I am not sure that my approach is right, especially on proving right to left. Please check whether my approach is right, ways to improve it,  and some other ways of proving this question. zsh I/O redirection: redirecting and then piping; what is going on? Can somebody explain what is going on in this command:  echo foo &gt;&amp;2 | grep foo   Zsh (5.0.2) prints foo twice. One seemingly to stdout and one to stderr, since running these commands:  { echo foo &gt;&amp;2 | grep foo } &gt;/dev/null   and:  { echo foo &gt;&amp;2 | grep foo } 2&gt;/dev/null   both just print foo once. This is a trivial problem, but it annoys me that I can't get to the bottom of it:  I'm running Windows 8, Powershell version 3.0. By right-clicking on the title bar I can go into the Properties and change the font, size, background colour etc without any problems.  After closing and restarting Powershell, all of the changes I've made stick except that if I've set the font to Lucida Console then on reopening I get the Raster font.  (Note that all of the above applies to when I run Powershell as Administrator.)  So:   If I set the font to Lucida, then it switches to Lucida for the remainder of the session. If I set the font to anything other than Lucida, then it stays as that after closing and reopening. If I alter the window sizes or text colours or anything else, the changes persist after reopening. The only thing that goes wrong is that if I set the font to Lucida, it switches to 'Raster fonts' when I reopen. But cmd and powershell ISE don't have this problem - only the powershell console.   Can anyone suggest what might be going wrong?  (One observation I've made is that upon re-opening Powershell after setting the font to Lucida, at first the width of the window is what it would be if the font were Lucida, but then after a second, it widens slightly to accommodate the raster font.) I would like to get an alert (with sound) when my laptop battery is fully charged.  How can I do that? how to remove frost free outdoor faucet drain valve assembly I've tried unscrewing the part outlined in red below. No dice. Do I just need to remove the whole rod (above the red outline) and replace it?) If so, can anyone point me to instructions for them.  I can't see in there. Worried that I'll pull it out and not be able to put it back in.  (The deeper I go in the plumbing the more things I find that there is no modern fitting-part :)  My new assembly  replaces the parts outlined in red. the new assembly has a female thread. I am HOPING that the thicker part of the pipe (just above the black "collar" stopper)  is screwed onto the pipe above.  However, I cannot unscrew it. There is nothing to get a hold of. It's perfectly round. I've tried dw40, and let it sit for 20 minutes. No love.  I'll try wacking it with a board in the direction along which it moves in when it screws (perpendicular to the threads per [this answer][2]) Question: If $c\neq 1$ is an $n^{th}$ root of unity then, $1+c+...+c^{n-1} = 0$  Attempt: So I have established that I need to show that $$\sum^{n-1}_{k=0} e^{\frac{i2k\pi}{n}}=\frac{1-e^{\frac{ik2\pi}{n}}}{1-e^{\frac{i2\pi}{n}}} =0$$ by use of the sum of geometric series'. My issue is proceeding further to show that this is indeed true. Disclaimer: I'm pretty novice at sysadmin stuff.  I'm trying to set up port forwarding in an AWS EC2 instance, this has to be done in the command-line because I don't want to go in and edit anything, it has to be automatic (it's part of a build process).   sudo echo "net.ipv4.ip_forward = 1" &gt;&gt; /etc/sysctl.conf      Permission denied   The weird thing is I've been (successfully) using sudo for pretty much every command that required su privileges. If I do sudo su before the command (trying it out by hand in an ssh session), then it works.  Reasons behind this? Possible solutions that don't involve sudo su or manual edits? On convergence of Bertrand series $\sum\limits_{n=2}^{\infty} \frac{1}{n^{\alpha}\ln^{\beta}(n)}$ where $\alpha, \beta \in \mathbb{R}$ Study the convergence of $$\sum_{n=2}^{\infty}  \frac{1}{n^{\alpha}\ln^{\beta}(n)}$$ where $\alpha, \beta \in  \mathbb{R}$   I have proved that:   This series diverges when $\alpha \leq 0$. This series converges when $\alpha &gt; 1, \beta &gt; 0$ This series diverges when $0 &lt; \alpha &lt; 1, \beta &gt; 0$ This series converges when $\alpha = 1, \beta &gt; 1$      Question: What happens when $\alpha &gt; 0$ and $ \beta &lt; 0$?   There are other questions on MSE which ask about this series, but this question is distinct because   I would like an argument which does not rely on the integral test for series convergence, and this question considers all real $\alpha$ and $\beta$, while other questions ask only about $\alpha, \beta &gt; 0$, where we can apply Cauchy condensation criterion How do I determine the size of my array in C?   That is, the number of elements the array can hold?