I already tried adding more subivisions, tweaked the light bouncing parameters, etc, but I cannot get rid of the black pixels when using  Cycles material copied from a YouTube video.    Here is the source if someone wants to check it out:    Thanks!
I know that this question is a bit old or maybe overdone, but I'm running the latest edition of Blender and when I use the Cycles engine I get really fuzzy results and I can't find a simple, non-compromising solution to the quality.  I don't know exactly what I'm doing wrong here, but I'm sure others share my frustration.  Leaving everything in default settings, I started a new project and switched to the Cycles render.  I duplicated the cube and set colors for two Diffuse BSDF shaders, then went ahead and made walls and a floor all sharing the same diffuse shader.  I made two windows to emit blue light.  The screenshot has gaps between the walls because of the setup:  I'm aware that it's considered very incomplete and many have come to terms with some amount of noise, but is this normal?  Furthermore, with default settings or not, I can't change the amount of noise produced.  Supposedly, using "progressively refine" in the rendering tab should make it refine itself indefinitely, however Cycles only counts to 10 refines and then stops, creating a render which is a pixel-perfect match of the ordinary rendering method when it's completed.  I understand that there are tricks that can be used to reduce noise, but at the cost of extra processing time and usually small quality conflicts, like blurring.  My question essentially boils down to is this Cycles' current limit?
Name of mean absolute error analogue to Brier score? Yesterday's question  got me curious about probability scoring. The  $$\frac{1}{N}\sum\limits _{i=1}^{N}(\text{prediction}_i - \text{reference}_i)^2$$ is a mean squared error measure. Does the analogous mean absolute error performance measure $$\frac{1}{N}\sum\limits _{i=1}^{N}|\text{prediction}_i - \text{reference}_i|$$ have a name, too? Using Green's identity to show that a harmonic function with zero boundary values is identically zero I am confused how to do this question. I need to use Green's first identity and if $\nabla(f)=0$ then $f$ is constant on $\Omega$ since $\Omega$ is path connected.  I have subbed in the information into green's identity but I don't get anything useful.  $$\iiint_\Omega \nabla f\cdot \nabla g \,dV =\iint_{\partial\Omega} f\nabla g\cdot n \,dA - \iiint_\Omega f\cdot \Delta g \,dV$$   We get:  $$\iiint_\Omega \nabla f\cdot \nabla g \,dV =-\iiint_\Omega f\cdot \Delta g \,dV$$   $$\iiint_\Omega \nabla. (f \nabla g) \,dV =0$$ $$\iint_{\partial\Omega} f\nabla g\cdot n \,dA=0$$ Proof of $a^n+b^n$ divisible by $a+b$ when $n$ is odd Python HTTPS requests (urllib2) to some sites fail on Ubuntu 12.04 without proxy I have an little app I wrote in Python and it used to work... until yesterday, when it suddenly started giving me an error in a HTTPS connection. I don't remember if there was an update, but both Python 2.7.3rc2 and Python 3.2 are failing just the same.  I googled it and found out that this happens when people are behind a proxy, but I'm not (and nothing have changed in my network since the last time it worked). My syster's computer running windows and Python 2.7.2 has no problems (in the same network).  &gt;&gt;&gt; url = 'https://www.mediafire.com/api/user/get_session_token.php' &gt;&gt;&gt; response = urllib2.urlopen(url).read()   File "/usr/lib/python2.7/urllib2.py", line 126, in urlopen     return _opener.open(url, data, timeout)   File "/usr/lib/python2.7/urllib2.py", line 400, in open     response = self._open(req, data)   File "/usr/lib/python2.7/urllib2.py", line 418, in _open     '_open', req)   File "/usr/lib/python2.7/urllib2.py", line 378, in _call_chain     result = func(*args)   File "/usr/lib/python2.7/urllib2.py", line 1215, in https_open     return self.do_open(httplib.HTTPSConnection, req)   File "/usr/lib/python2.7/urllib2.py", line 1177, in do_open     raise URLError(err) urllib2.URLError: &lt;urlopen error [Errno 8] _ssl.c:504: EOF occurred in violation of protocol&gt;   What's wrong? Any help is appreciated.  PS.: Older python versions don't work either, not in my system and not in a live session from USB, but DO work in a Ubuntu 11.10 live session. Do I need quote marks when I quote myself? Hello language lovers,   English isn't my first language and I would like to know if I need to use quotation marks when I quote something I said in the past. .NET - How can you split a "caps" delimited string into an array? How do I go from this string: "ThisIsMyCapsDelimitedString"  ...to this string: "This Is My Caps Delimited String"  Fewest lines of code in VB.net is preferred but C# is also welcome.  Cheers! $AB-BA=I$ having no solutions Razr Maxx HD, How to wipe data with broken screen My screen is totally destroyed, it's black and unresponsive. The phone turns on just fine, though. I just got my new phone and I have to send this one back now.  I want to wipe the phone before I send it back, but I'm not sure how. I don't care too much about sending back a rooted phone, it seems Asurion doesn't really care about that from what I've read, but I don't want my personal data on the phone when I send it in.  What are my options to wipe the phone without a screen? I've already read a lot of threads on other forums and here on the subject, but everyone seems to say to wipe through ADB shell. Well, I can see the phone in ADB, but I am unable to enter SU through ADB shell. I assume it's because the screen is locked, and I have no way to unlock it. Others have also said to wipe through fastboot in ADB, but I am seeing conflicting recommendations and I'm not sure how to proceed. I'm not that proficient with ABD, so I want to make sure I don't mess this up.  Any advice would be greatly appreciated. Given 3 distinct primes {$p,q,r$}, then $|G|=pqr \implies G$ not simple How to set metadata for music files? In windows music files have metadata like artist name, album name associated with them. How is this metadata stored. Is it stored in file system like other file attributes or is it part of MP3 data that Windows Explorer extracts using a MP3 reader plugin?  Is it possible to read/change this information in Linux? Is it possible with commandline?  (I know these attributes can be set using Rhythymbox or some music player but I'm curious if these could also be set directly. Like in Windows the windows itself shows you artist information if you right click the file and open properties dialog) Are there any security risks using a single key-pair for both key-exchange and signing?  I'm mainly interested in using Curve25519 for key-exchange and Ed25519 for signing. But similar combinations, such as EC-DH and EC-Schnorr or even EC-DSA with the same key pair would be interesting too.   Curve25519 hashes the output of an x-coordinate only Diffie-Hellman key exchange Ed25519 is a slight variant of EC-Schnorr signatures.   I saw some recommendations to avoid using a single key for multiple purposes, but I couldn't find anything concrete. Create an interface which is similar to the material list box Is it possible to explicitly tell Stack Overflow the language of the code block you are including? Possible Duplicates:             Stack Overflow awesomely detects what language a code block is and syntax highlights it accordingly. But sometimes it fails. Is it possible to explicitly tell it what the language is?  php:  if ( force_ssl_admin() &amp;&amp; !is_ssl() ) {     if ( 0 === strpos($_SERVER['REQUEST_URI'], 'http') ) {         wp_redirect(preg_replace('|^http://|', 'https://', $_SERVER['REQUEST_URI']));         exit();     } else {         wp_redirect('https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);         exit();     } }   ruby:  def destroy   @payment = Payment.find(params[:id])   @payment.destroy    redirect_to :back end   yaml (FAIL)  foo: this is foo! bar: this is bar! id: 5 Gravity in 2d space and inverse linear law In our three-dimensional universe, gravity obeys the inverse square law. In a four-dimensional universe, gravity would be expected to obey the inverse cube law et cetera.  In a two-dimensional universe, one would similarly expect gravity to obey an inverse linear law. I've seen it claimed that this is not actually true, when you work it out according to general relativity there would actually be no gravity at all in such a universe. Is this true? If so, is there a layman's explanation of why? Is it related to the fact that gravitational potential wells would be infinitely deep?  Would electrostatic forces follow the same law as gravity?  If there existed infinitely long strings in our universe, would they have the same gravitational effect as point particles in a 2d universe? EL proposals / autocomplete / code assist in Facelets with Eclipse What's the point in adding a new line to the end of a file? Some compilers (especially C or C++ ones) give you warnings about:  No new line at end of file   I thought this would be a C-programmers-only problem, but github displays a message in the commit view:  \ No newline at end of file   for a PHP file.  I understand the preprocessor thing explained in , but what has this to do with PHP? Is it the same include() thing or is it related to the \r\n vs \n topic?   What is the point in having a new line at the end of a file? C++ preprocessor __VA_ARGS__ number of arguments Compton scattering vs. photoelectric effect Say a photon hits some atom.  What determines whether there will be a photoelectric effect (photon is absorbed, electron is released) or whether there will be a Compton scattering (the photon is  scattered at some angle, and the electron is released with another direction)? Fingerprint GUI not installing in Ubuntu 20.04 I'm trying to install fingerprint-gui on my Lenovo Ideapad 520 having Ubuntu 20.04 on which fingerprint isn't working for now. I tried going directly to Settings → Users → Automatic login and enabled the fingerprint login, but the error is:  Could not access any fingerprint readers Please contact your system administrator for help!  I also tried to install Fingerprint GUI: sudo apt-add-repository ppa:fingerprint/fingerprint-gui &amp;&amp; sudo apt-get update  sudo apt-get install libbsapi policykit-1-fingerprint-gui fingerprint-gui  but encountered this error: E: Package 'policykit-1-fingerprint-gui' has no installation candidate E: Package 'fingerprint-gui' has no installation candidate  What could be the problem here? How to redirect output of an entire shell script within the script itself? Is it possible to redirect all of the output of a Bourne shell script to somewhere, but with shell commands inside the script itself? Redirecting the output of a single command is easy, but I want something more like this: #!/bin/sh if [ ! -t 0 ]; then     # redirect all of my output to a file here fi  # rest of script...  Meaning: if the script is run non-interactively (for example, cron), save off the output of everything to a file.  If run interactively from a shell, let the output go to stdout as usual. I want to do this for a script normally run by the FreeBSD periodic utility.  It's part of the daily run, which I don't normally care to see every day in email, so I don't have it sent.  However, if something inside this one particular script fails, that's important to me and I'd like to be able to capture and email the output of this one part of the daily jobs. Update: Joshua's answer is spot-on, but I also wanted to save and restore stdout and stderr around the entire script, which is done like this: # save stdout and stderr to file  # descriptors 3 and 4,  # then redirect them to &quot;foo&quot; exec 3&gt;&amp;1 4&gt;&amp;2 &gt;foo 2&gt;&amp;1  # ...  # restore stdout and stderr exec 1&gt;&amp;3 2&gt;&amp;4