Transit Visa & Baggage
Is there a way to find out if I need a transit visa for a layover in the UK?
I just visited Ask Ubuntu (askubuntu.com) while logged into Stack Exchange, and noticed that "join this community" doesn't appear:    It is similarly broken on Math Overflow (mathoverflow.net). It works, however, on all sites that are subdomains of stackexchange.com, like Mathematics (math.stackexchange.com) and Academia.  I'm using Google Chrome version 46.0.2490.86 on Windows 8.1 Update 1.  (I don't know if this can actually be fixed, given how cookie security works, but I figured Stack Exchange should be aware of the issue.) What is the point of the Red Thread/Tape around evidence or newspaper clippings? I have seen in a lot-lot of movies that the person who searches for a crime or another person creates a web of red tape or wire around the newspapers and evidence he acquires. I never guessed its usefulness and am therefore asking why do they do it?  Here is an illustration I created: Finding the maximum likelihood estimators for this shifted exponential PDF? Alternative to LibreOffice Base for Ubuntu Using customized Coordinate System in ArcGIS Desktop? I don't know so much about coordinate systems...  In my office we use to deal with spatial data coming from archaeological sites. Each site has its own x-y-z coordinate system (GCS). Three simple ortogonal cartesian axis. In the last years we have been managing this spatial data through GIS software (ArcGIS), without using specific coordinate system (just leave it as "undefined")  I'd like to know if there exisits any GCS designed to deal with such datasets using simple cartesian orthogonal axis, without grid distortions of the typical GCS. In addition, I'd like to know if this system is suitable for using it in an online mapping application.  By the way, we manage 2D (ArcMap) and 3D (ArcScene) environments and work with "mm" as length base unit.   If such a thing doesn't exists, maybe someone knows how to create it. How to set vertex weights using Blender's Python API? Looking at the API docs I found , but It cannot be called in Edit Mode. When I try to call it, I always get:     RuntimeError: VertexGroup.add(): cannot be called while object is in edit mode.   The buttons in the vertex group list use bpy.ops.objects.vertex_group_assign(), but to work with it you have to manipulate selections, this is not nice to do from a script.    Why I try to use VertexGroup.add() in Edit Mode? My script works this way:  Human weight paint a bone, "Arm_1.L", "Arm_1.L" shares vertices with "Arm_2.L" in this case they share half the vertices (4 bone arm rig, trick to have nice deform in certain movements). When script run, all selected vertices that exist in both groups (Arm_1.L and Arm_2.L) will copy the weights of Arm_1.L into Arm_2.L but inverted. This way, I only need to weight paint "Arm_1.L" and "Arm_3.L", the script will fill the weights for "Arm_2.L".  import bpy  # ensure we are in edit mode bpy.ops.object.mode_set(mode="EDIT")  # configurable parameters src_group = "Arm_03.L" dst_group = "Arm_02.L"  obj = bpy.context.edit_object src_group_index = obj.vertex_groups[src_group].index dst_group_index = obj.vertex_groups[dst_group].index  mesh = obj.data sel_verts = [v for v in mesh.vertices if v.select] #sel_verts = mesh.vertices  # SEGFAULT in this line bpy.ops.object.mode_set(mode="OBJECT")  print("Working")  for v in sel_verts:     v1in = False     v2in = False     for g in v.groups:         if g.group == src_group_index:             v1in = True         if g.group == dst_group_index:             v2in = True     if v1in and v2in:         print("True")         obj.vertex_groups[dst_group].add([v.index], 1.0 - obj.vertex_groups[src_group].weight(v.index), 'REPLACE')  print("Finished") Creating System-Wide Keyboard Shortcut To Launch Applications I recently switched from Ubuntu, and I was feeling very comfortable with using Ctrl + Alt + T to launch terminal. Can I assign Shift + Cmd + T to do the same thing in Yosemite? Specifically, I want a new terminal window to be opened. Polynomial bounded real part of an entire function Let $f(z)$ be an entire function whose real part is bounded by a polynomial in $|z|$. Does it follow that $f(z)$ is a polynomial?  Or, without loss of generality and more suggestively $$(f(z)=\sum_{k=0}^\infty a_k z^k \quad \land \quad \operatorname{Re}(f(z))\leq |z|^n)\quad \forall z\in \mathbb{C} \qquad \Rightarrow \qquad f(z)=\sum_{k=0}^n a_k z^k \quad\forall z\in \mathbb{C}$$ How can I easily encrypt a file? My 1.12 solution can be found . When trying to update command blocks to 1.13, I have the following:  scoreboard objectives add invert dummy   (run at start) then:  scoreboard players set FakePlayer invert 1   (impulse unconditional repeat) chained into:  execute at @e[tag=summoned] run scoreboard players reset FakePlayer invert   (chain unconditional repeat) chained into:  execute if score FakePlayer invert = 1 invert run say "All summoned animals are dead!"   This should reset FakePlayers score continuously until all entities with tag "summoned" are dead, then it should run the final condition. This does not happen, and I can't see why. Here is a question as phrased in Advanced Linear Algebra (Steven Roman):     Show that a linear operator $\tau$ on a finite-dimensional complex inner product space $V$ is normal if and only if whenever $S$ is an invariant subspace under $\tau$, so is $S^\perp$.   I'm only interested in the $\Rightarrow$ direction. Wikipedia (and ProofWiki)  that uses some kind of computation with the trace. Linear Algebra Done Right chooses an orthonormal basis and then uses the fact that $\Vert \tau v \Vert = \Vert \tau^* v \Vert$.  However, the above  proofs seem a bit too computational to me. Can the following argument work?  (Use $\odot$ for orthogonal direct sum.) Suppose that $\tau$ is normal and write $$V=E_{\lambda_1} \odot \cdots \odot E_{\lambda_k}$$ where the $E_{\lambda_i}$ are the eigenspaces of $\tau$. If $S$ is a $\tau$-invariant subspace then $\tau|_S$ is diagonalizable, so $$S=\widetilde{E}_{\lambda_1} \odot\cdots\odot \widetilde{E}_{\lambda_k}$$ where the $\widetilde{E}_{\lambda_i} \le E_{\lambda_i}$ are the eigenspaces of $\tau|_S$ (which could be trivial). Then choose orthogonal complements $D_i$ such that $E_{\lambda_i} = \widetilde{E}_{\lambda_i} \odot D_i$, and then $$S^\perp = D_1 \odot\cdots\odot D_k.$$ Since each $D_i$ is a subspace of an eigenspace, they are all $\tau$-invariant. Fluent and Query Expression — Is there any benefit(s) of one over other? LINQ is one of the greatest improvements to .NET since generics and it saves me tons of time, and lines of code.  However, the fluent syntax seems to come much more natural to me than the query expression syntax.  var title = entries.Where(e =&gt; e.Approved)     .OrderBy(e =&gt; e.Rating).Select(e =&gt; e.Title)     .FirstOrDefault();  var query = (from e in entries              where e.Approved              orderby e.Rating              select e.Title).FirstOrDefault();   Is there any difference between the two or is there any particular benefit of one over other? As mentioned on :     For something that can be done so   easily by accident, there should be   the ability to undo mistakes.   I know that I have clicked several times on a comment up-vote without actually wanting to.  I would suggest being able to cancel the up-vote (maybe only for a couple of minutes or even less than a minute, no problem, as long as I can undo a miss-click). Posts linked in deleted answers still show up under "Linked" E.g. see . Problems with macOS path on Synology NAS (SMB) I am having issues with macOS where, after mounting a drive it will mount new drives instead of just jumping to the sub-folder path within the mounted drive.   For example, I'm seeing where I send someone a path for in the "Video" drive on a Synology (smb://HAL9000/Video).  Instead of mounting the "Video" drive (smb://HAL9000/Video) and going to a sub-folder within the video drive labeled "GoPro -IMPORT", it will create a new drive on their desktop labeled "GoPro - IMPORT".    If I create a new sub-folder within "GoPro - IMPORT" and send them a link to that like (smb://HAL9000/Video/GoPro%20-%20IMPORT/Test), instead of taking to the sub-folder in the "Video" drive that they already have mounted on their desktop, it will create an entirely new drive labeled "Test" on their desktop.    I've tried reaching out to both Apple and Synology and had no luck with this.  I would appreciate any kind of help/support. General solution to the PDE $xU_x+yU_y=0$ Solve the equation $xU_x+yU_y=0$.   From Partial Differential Equations: An Introduction, 2nd Ed. (Strauss, pg. 10). There are no boundary conditions.  Solution: The PDE can be written $(x,y)\cdot\nabla U(x,y)=0$, implying that the vector $(x,y)$ is tangent to the PDE's characteristic equation. Then I can write $dy/dx=y/x$, and to solve this ODE,  $$\frac{dy}{dx}=\frac yx \\ \ln y=\ln x+c_1 \\ y=cx \\ y/x=c$$  Hence, the PDE is dependent on $c$ and I can write $U(x,y)=f(y/x)$ for some function $f$, solving the problem.  Question: Is this solution correct? The hint for the question (supplied by the professor) said I should use a substitution of variables, but this seems reasonably valid. When I run the logistic regression, two independent variables have VIF values greater than 10 like 13 or so. Logistic regression is the one I will use to measure the overall change in the dependent variable with one incremental changes in every each independent variable. However, when I run the linear regression model version on my same data, the VIF values I get from all the independent variables are either slightly greater than 1 or around 5 or 6. Besides, all the coefficients are highly significant all below 0.01.  If so, is it safe to use my logistic regression model to find out the incremental effect of every each independent variable without dropping out any independent variables?   If my purpose is to find an incremental effect of every each independent variable on the overall dependent value in a logistic regression model, is multicolinearity an important problem to consider? Can I ignore it?   If my p-values are all less than 0.01 which is the same indicator as t-value, will I still need to worry about colinearity issue even though my VIF scores for two variables are around 13-14? Based on what you said, if p-value is safe enough, will this be still a problem?  I am also referring to the following website comment:                                                                     So, in sum, my ultimate goal is to use the final output from the logistic regression model generated from the independent variables and one binary dependent variable. If so, do you think I can ignore the multicolinearity problem? When does a Square Matrix have an LU Decomposition? How does gravity work underground? Would the effect of gravity on me change if I were to dig a very deep hole and stand in it? If so, how would it change? Am I more likely to be pulled downwards, or pulled towards the edges of the hole? If there would be no change, why not? iPhone App › Add voice recognition?