Add layer in group on QGIS using Pyqgis
Add layer to a QGIS group using Python
Prove that $f(x)\in \mathbb{Z}[x]$ such that $f(0)$ and $f(1)$ are odd has no integer roots Switching baselayers as user zooms in to map in OpenLayers? If a two vectors $\bf u$ and $\bf v$ in linearly independent, can their images be linearly dependent given they were transformed by a linear transformation $T$? I think not. My reasoning If the images are linearly dependent, then $c_1T({\bf u})+c_2T({\bf v})={\bf 0}$ for scalars $c_1$ and $c_2$, not both $0$. Then $c_1T({\bf u})+c_2T({\bf v})={\bf 0}$ $T(c_1{\bf u}+c_2{\bf v})=T({\bf 0})$ $c_1{\bf u}+c_2{\bf v}={\bf 0}$ Therefore, ${\bf u}$ and $\bf v$ are linearly dependent. My reservation A homework problem seems to contradict the above. Here's the problem: Let $\mathbb R^n\rightarrow\mathbb R^m$ be a linear transformation. Suppose $\{{\bf u},{\bf v}\}$ is a linearly independent set, but $\{T({\bf u}),T({\bf v}\})$ is a linearly dependent set. Show that $T({\bf x})={\bf 0}$ has a nontrivial solution. check if "it's a number" function in Oracle Our iPad is locked and we're not sure of the Apple ID / iCloud password Let $n\in\mathbb N$ and let $a_1,\ldots,a_n$ be natural numbers smaller than $10^n$. Write each $a_k$ in base $10$ and add $0$'s to the left of each decimal expansion, if needed, so that each $a_k$ is written with $n$ digits. Consider the matrix such that the entries of the $k$th row are the digits of $a_k$ (written in the same order). Let $d\in\mathbb N$ be such that $d$ divides each $a_k$. Prove that $d\mid\det A$.   For instance, suppose that $n=4$ and that your numbers are $3876$, $2784$, $684$, and $8388$, each of which is a multiple of $12$. Then$$A=\begin{bmatrix}3 &amp; 8 &amp; 7 &amp; 6 \\  2 &amp; 7 &amp; 8 &amp; 4 \\ 0 &amp; 6 &amp; 8 &amp; 4 \\  8 &amp; 3 &amp; 8 &amp; 8\end{bmatrix}$$and $\det A=-360$, which is, in fact, a multiple of $12$.  I learned about this problem yesterday. I found it quite cute and I decided to share it with all of you.  Note: I know how to prove it. Is returning a pointer to a static local variable safe? I'm working with some code that widely uses the idiom of returning a pointer to a static local variable.  eg:  char* const GetString() {   static char sTest[5];   strcpy(sTest, "Test");   return sTest; }   Am I right in thinking that this is safe?  PS, I know that this would be a better way of doing the same thing:  char* const GetString() {   return "Test"; }   Edit: Apologies, the function signature should of course be:  const char* GetString(); How to render as only wireframe in Cycles? We are sponsoring a family to visit us in UK as friends from Madagascar for two weeks. They have a 6 year old and a 16 month old.   Do the kids need their own visas, and are they the standard visitor visa or a special child visa?   Also, when I try and apply on the website I can only apply for one person so how do I apply for all the individuals in the family?   I have looked on the Immigration website and can't find the answers I need. Why didn't Harry Potter tell Aunt Petunia he was rich to improve how he was treated by Dursleys? This is a follow-up question to   One reason Aunt Petunia mistreated Harry was that she did not know he was rich. If she knew, she would naturally have treated this golden goose nicely. Her retirement would be secured if Harry financially supported her in old age.  Why didn't Harry tell Aunt Petunia he was rich? Surely every boy wants to be treated nicely by his family. Is it possible to construct a multi-colored double-bladed lightsaber? I was just watching  video of some SW dueling at the 2015 World Fencing Championship, and wondered if it's actually possible in the SW universe to construct a multi-colored double-bladed lightsaber?   Are there any accounts of such a thing? If not, would it at least be theoretically possible to make one, or, are there obvious limitations? Change of flavour, Weak interaction I couldn't find a straight and clear answer to this question on the internet: Why is the weak interaction (charged), the only interaction which can change the flavours of the quarks? Selling customized versions of Ubuntu My question is next: "Can I modify some version of Ubuntu Linux, add some software related to electrical engineering, modify look and some functions of Ubuntu, basically customize the entire system so it suits the needs of electrical engineers working on the field or in the office, and then that customized system sell in order to make profit?"   I'm not sure am I allowed to do that (is it legal?), so I would appreciate answer. How do I choose a macro lens for a Canon APS-C camera? A friend has been kind enough to lend me a DSLR for a few months.  It's my first foray into DSLR photography, or indeed any kind of photography beyond simply aiming my Canon IXUS at something and clicking the button.    Over the last few weeks, I've been busy studying, practising and trying to learn as much as possible ahead of a planned trip to Norway where I hope to see, and get some photos of, the Aurora Borealis.  I currently have:   Canon Rebel Xsi (450D) Canon 50mm f/1.4 L  Canon 18-55m kit lens Aluminium full height tripod with ball head Cable release Spare battery &amp; memory cards   I'm prepared to spend the night wrapped up outdoors, in the hope that they will make an appearance. I'd like some advice on how to get the most out of this kit for the trip:   How should I go about setting up to get pics of the Aurora?  How might I achieve optimum focus? From what I've read, I'll need to use the tripod and cable release, with IS turned off, on continuous shooting mode with long exposure times. But I'd like some more specific tips in terms of which aperture and ISO settings might work best? Should I use one of the lenses above, or would it be worthwhile renting a better, wide angle lens; if so, which would you recommend? Let's assume we have a table where it has two columns, one an ID and one an hstore column, which stores key/value pairs.  You could query that column as such:  SELECT name, attributes-&gt;'device' as device FROM products WHERE attributes-&gt;'edition'= 'ebook'   Can you create a view for this table where the keys/values appear as columns in the view instead of all in the hstore column?  Example: I have an hstore key where it might have the key of amenity.  I want to create a view showing the the ID and the amenity values in a new view. How do I enable hardware virtualization technology (VT-x) for use in Virtualbox? So I am trying to run Ubuntu in a virtualbox but on installing 12.10 from the .iso I was greeted by a warning telling me that audio wouldn't work then I pressed next and this popped up:  Failed to open a session for the virtual machine Tux 3 VT-x features locked or unavailable in MSR (VERR_VMX_MSR_LOCKED_OR_DISABLED) Details  Result Code:  E_FAIL (0x80004005) Component:  Console Interface:  IConsole {db7ab4ca-2a3f-4183-9243-c1208da92392}   And then it doesn't work.  I assigned 4GB of my 8GB to Ubuntu, 100 dynamically allocated GB of space, and 12MB of graphics memory. I'm running an Asus p8z77 V LX mobo with an Intel i5 3550 processor.   Downloaded 12.04.2 on my PC and tried again. Still getting the same message. Showing that the roots of a polynomial with descending positive coefficients lie in the unit disc. In Star Trek, does the original die in teleportation? I am just curious.  If I am teleported is the original me dead and the teleporter just makes another copy of me there[at destination]? Get steam to realize I have games already installed I uninstalled and re-installed steam. I didn't uninstall my games, and they still exist on my hard drive (I checked).  I have an SSD and a HDD, and to save space I install programs (including steam) to C:\Program Files (x86)\Steam drive (SSD) and games to D:\Games\SteamApps (HDD). How to I let steam know the programs are installed there?