I've got an image, it's an RGB 8 bit.     But when i save it as png, i don't see the transparency, it's all white
When handling multiple white-on-transparent png images, I am hindered by the fact that the thumbnails of these images are all-white. Both Adobe Bridge CS6 and Windows Explorer suffer the same problem, I can't discern between two of these pngs.  Is there a way to make these thumbnails useful? Is there some setting I missed that allows changing the thumbnail background colour for a png -- now a deafult white?
I have an array of Foo objects. How do I remove the second element of the array?  I need something similar to RemoveAt() but for a regular array. 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 ...] Is there a standard pronunciation for gender-neutral -@ or -x More and more I see, especially in activist communities, Spanish-derived words ending in x or @ in order to neuter the gendering inherent in the original language. For example: latinx (or latin@) as opposed to latina and latino. How, though, are these endings pronounced? Please provide evidence of how this orthography is most commonly pronounced. Note 1: I recognize this is in an English Language site, rather than a Spanish language site, but this phenomenon is very much happening in English, albeit with Spanish loan words. Therefore the question is relevant to non-Spanish-speaking English speakers. Note 2: A question like this can lead to politically charged or, at least, sarcastic comments. Please refrain from bringing in your biases for or against. Note 3: This question is not seeking opinions as to how some people pronounce the suffixes. Answers should address evidence of a developing orthodoxy in pronunciation. What does "sudo apt-get update" do? I am wondering what sudo apt-get update does?  What does it update? I'd like to use epigrafica specifically for chapters and sections, but like to use times font for main texts.  \usepackage{epigrafica}          % for chapter/section \usepackage{newtxtext,newtxmath} % for main text   Is there any way to do this? I can only use pdftex. Is there a way to save composite node presets? Is there any way in Blender to save settings in your compositing node setup. For example say for my shadow catcher I have it setup for a hard shadow for sunlight, and then I also have a setting for diffuse light shadow for indoors. Is there any way I can save these settings individually so I can quickly switch to them rather than having to individually change the nodes every time. My kids are playing Minecraft on 2 PCs, creative mode.  They are connected by the way of one of them starts a single player game on the other one than joins that game over the LAN.  Can I, using Minecraft PE on my iPad, join their game as well? Georeferencing scanned map using ArcMap? What are LiDAR returns? Can someone help with an explanation and some references, in order to understand the nature of return pulses within a LiDAR system. Mounting filesystem with special user id set "is" operator behaves unexpectedly with integers Why does the following behave unexpectedly in Python?  &gt;&gt;&gt; a = 256 &gt;&gt;&gt; b = 256 &gt;&gt;&gt; a is b True           # This is an expected result &gt;&gt;&gt; a = 257 &gt;&gt;&gt; b = 257 &gt;&gt;&gt; a is b False          # What happened here? Why is this False? &gt;&gt;&gt; 257 is 257 True           # Yet the literal numbers compare properly   I am using Python 2.5.2. Trying some different versions of Python, it appears that Python 2.3.3 shows the above behaviour between 99 and 100.  Based on the above, I can hypothesize that Python is internally implemented such that "small" integers are stored in a different way than larger integers and the is operator can tell the difference. Why the leaky abstraction? What is a better way of comparing two arbitrary objects to see whether they are the same when I don't know in advance whether they are numbers or not? Microsoft recommends using Rowversion over timestamp, but I can not find "rowversion" data type inside my sql server 2008 R2 Microsoft  mentioned that we should use the rowversion data type over Timestamps. Now inside my SQL Server 2008 R2, I want to create a column with the Rowversion data type. But in my SQL Server 2008 R2 Management Studio, I cannot find such a data type:  Also when I tried altering existing column named timestamp which is of type timestamp using this statement: ALTER TABLE [SkillManagement].[dbo].[Customer] ALTER COLUMN timestamp rowversion   I get this error: Msg 4927, Level 16, State 1, Line 1 Cannot alter column 'timestamp' to be data type timestamp  Can anyone advise? EDIT Since I want to protect my ssh connections, I set some global cipher suite options to restrict set of used algorithms. But recently I've encountered a server which doesn't support some of those algorithms. So, I need to selectively enable deprecated algorithms for a specific host record in client (my system) configuration.  I found out that the options override is not working as I expected. Let's take a minimal (not-)working example for the github:  HostKeyAlgorithms ssh-ed25519-cert-v01@openssh.com,ssh-ed25519,ecdsa-sha2-nistp521-cert-v01@openssh.com,ecdsa-sha2-nistp521,ecdsa-sha2-nistp256  Host github     HostKeyAlgorithms ssh-rsa     Hostname        github.com     Port            22     User            git     PubkeyAuthentication yes     IdentityFile    ~/.ssh/some-filename-here   Having that, I receive the following error (HostKeyAlgorithms is not overriden at all):  debug1: /home/username/.ssh/config line 14: Applying options for github &lt;...&gt; debug2: kex_parse_kexinit: ssh-ed25519-cert-v01@openssh.com,ssh-ed25519,ecdsa-sha2-nistp521-cert-v01@openssh.com,ecdsa-sha2-nistp521,ecdsa-sha2-nistp256 &lt;...&gt; Unable to negotiate with 192.30.252.130: no matching host key type found. Their offer: ssh-dss,ssh-rsa   It is similarly not working for the global PubkeyAuthentication no options with an override in a host configuration.  Also, the match doesn't help either:  match host github     HostKeyAlgorithms ssh-rsa   So, is there a way to selectively redefine those options?  NOTE: I'm using the openssh-7.1_p2-r1 on gentoo. I'm looking to download and install the latest version of Ubuntu to replace the current version of Windows I had pre-installed on my machine when bought it.   I have some really neat features on the machine that I really am hoping will still work when I move over to Ubuntu.  Can someone please confirm if the below will still work and, if not, how I can get them to work:   The USB ports on my machine The ethernet or Network work port on the machine The HDMI output on the machine and finally, the built in webcam   Thanks Sam Is there an operation similar to inset that creates faces in the opposite direction? That is, instead of creating faces inwards, they create faces outwards? A normal inset operation:  What I would like: What are the Alternatives For RemasterSys? "Naturally occurring" non-Hausdorff spaces? It is not difficult for a beginning point-set topology student to cook up an example of a non-Hausdorff space; perhaps the simplest example is the line with two origins. It is impossible to separate the two origins with disjoint open sets. It is also easy for a beginning algebraic geometry student to give a less artificial example of a non-Hausdorff space: the Zariski topology on affine $n$-space over an infinite field $k$, $\mathbf{A}_{k}^{n}$, is not Hausdorff, due to the fact that polynomials are determined by their local behavior. Open sets here are in fact dense. I am interested in examples of the latter form. The Zariski topology on $\mathbf{A}_{k}^{n}$ exists as a tool in its own right, and happens to be non-Hausdorff. As far as I'm aware, the line with two origins doesn't serve this purpose. What are some non-Hausdorff topological spaces that aren't merely pathological curiosities? Human vs. alien to avoid extinction by omnipotent being I'm reading .     The graph of $f: A \rightarrow B$ is the subset of $A × B$ consisting   of all ordered pairs $(a, b)$ with $f (a) = b$. If $A$ happens to be   $B^n$ for some $n ∈ N$, then we say that $f$ is a function on $B$ and   $n$ is the arity of $f$.   I don't understand the notation for the exponent of a set, I'm aware of what  is, it's the number of arguments or operands the function takes. I'm just not so sure if I can assume that a set with an exponent such as in $B^n$ means that a function has two operands.  I know the question may be too naive and perhapes the answer is the one I suggested and it's right in front of my face, I'm just searching for a confirmation or the negation of it. Thanks. Proof the Legendre polynomial $P_n$ has $n$ distinct real zeros