Want to know about divergence
What is divergence?
Uneven movement on camera following a path. I render a short movie. I set the camera to the circle curve to make it fly in circle. The problem is after render, the camera is a little shaky. Can anyone help me? Thanks first. When we say something in specified operating system, which preposition should I use?  e.g.     I play games {in/on/under} Windows. How do I test for a mob, with a given name, in a certain location? I want to testfor a sheep, by the name of Lamb, in a certain location using coordinates.  I have already tried this:  testfor @e[x=999,y=80,z=-1034,type=Sheep,name=Lamb]   But it doesn't work. I have also tried:  testfor @e[x=999,y=80,z=-1034,type=Sheep]   But it says it found a sheep whether or not there is actually a sheep in that location. How would I import/export Blender's preferences? What is the simplest way to generate a dodecahedron? I've been thinking of animating some dice and while most are easy to make, I'm having some trouble figuring out a way to generate a regular dodecahedron. I could hand build it but it would be potentially uneven. Would using the base of a 5 sided cylinder and then some variation on spin be the best option or is there a better way? What caused the apocalypse in the Hunger Games? So the stories of the Hunger Games are set in , a post-apocalyptic society situated in North America. Is there anything to explain what caused the Apocalypse? Whether from the main books, any extra material or interviews? (No fanfic please.)  As well as the cause, is there any indication of when the apocalypse happened? And how long after the apocalypse are the events of the Hunger Games? How to dump a man page? Greyed-Out vs Invisible When is $\phi(n)$ a prime number? I was thinking about this problem today. If $p$ divides $n$, then $p-1$ must divide $\phi(n)$. But $p-1$ is even for all primes greater than $2$, so must $\phi(n) = 2$ - the only even prime? I feel like this argument is shaky and not very rigorous! Efficiently select beginning and end of multiple contiguous ranges in Postgresql query I've got about a billion rows of data in a table with a name and an integer in the range 1-288.  For a given name, every int is unique, and not every possible integer in the range is present--so there are gaps.  This query generates an example case:  --what I have: SELECT * FROM ( VALUES ('foo', 2),               ('foo', 3),               ('foo', 4),               ('foo', 10),               ('foo', 11),               ('foo', 13),               ('bar', 1),               ('bar', 2),               ('bar', 3)      ) AS baz ("name", "int")   I'd like to generate a lookup table with a row for each name and sequence of contiguous integers.  Each such row would contain:  name   --  the value of the name column start  --  the first integer in the contiguous sequence end    --  the final value in the contiguous sequence span   --  end - start + 1  This query generates example output for the above example:  --what I need: SELECT *  FROM ( VALUES ('foo', 2, 4, 3),               ('foo', 10, 11, 2),               ('foo', 13, 13, 1),               ('bar', 1, 3, 3)      ) AS contiguous_ranges ("name", "start", "end", span)   Because I have so many rows, more efficient is better.  That said, I only have to run this query once, so it isn't an absolute requirement.  Thanks in advance!  Edit:  I should add that PL/pgSQL solutions are welcome (please explain any Fancy Tricks--I'm still new to PL/pgSQL). How to include time factor in a mixed model (investigating the interaction between two factors and time)? We are planning a trip with a bike rack attached to our trailer hitch. What is the best way to lock the bikes while the vehicle is unattended? I see some racks have locks on the knobs but they don't seem very strong.   What do you suggest? How to make GRASS and SAGA tools capable to use in QGIS？ I installed QGIS, GRASS and GDAL by OSGeo4w package, and as I finish the installation, I want to use GRASS tool, I face this problem：    But I already installed GRASS and SAGA, how to make those tools in QGIS to be used？ Why are there only two tangents to a hyperbola from a point, instead of four? Service or services? I've read many articles that use the term 'emergency services ' and ' location services' .   Why not service instead? Why must it be plural? Thank you Is there an expression to indicate the strategy of wearing someone down with numerous small irritations? I would use rope-a-dope, but it's got connotations of pretending to lose that I don't need. I'm trying to describe the behavior of someone who sends twenty detailed emails a day about various projects, and the recipient of his emails has finally gotten tired of trying to parse them, so the recipient just agrees to whatever he proposes. I'd like an expression that evokes both outward earnestness and hidden creepiness, like Uriah Heep, Dickens's "Humble servant" with veiled ambition, who overdoes it with professions of humility until he's in power. Water torture would work, but comes too close to a more racist expression that I'm not comfortable with. How to assign same Data to multiple object copies I made many copies of an object, then I thought it would've been better if I made them to share the same Data (being an instance of the same original object), I know how to do it one by one, is there a way to do it for all of them at once? I tried Copy Attribute add-on but didn't find what option can do that, or even if this is possible in the first place. YA novel where clumsy boy gains wings I'm trying to remember the name of a novel I read as a pre-teen.  If I recall correctly, it would have come out in the 90s (though it may have been a reprint).  The novel is set in modern times.  I recalled this because I've been reading a lot of urban fantasy lately, and this may be the first 'urban fantasy' book I read - our world, but with a touch of magic.  There's a somewhat clumsy, out of shape teenaged (or almost teenaged) boy who doesn't have a father.  His father had been a stage magician who was constantly frustrated by his son's complete inability to preform stage magic, despite a prediction saying he would have a great or powerful magic.  His father had died before the book started, I don't recall how long before.  The boy does something nice for an old woman (I don't recall what) and she gifts him a magical potion.  A drop of it, rubbed on his shoulder blades, will make him grow wings.  The book follows him for the summer, as he spends his evenings flying.  He makes himself a toga-like shirt out of some old curtains and spends time flying around at night.  I recall one scene where he learns about two children out in the middle of the bay (perhaps the book is set in San Fran?  I don't recall) in a rowboat with one oar.  He saves them (by pulling them back to shore using a rope they had with them) and gets mentioned in the paper as an angel.  At the end of the book, the potion has run out.  There's only a tiny little bit left, and when he rubs it in, it creates only a single feather.  Around that point, the boy realizes that he's no longer getting winded going up several flights of stairs and he's gained a lot of self-confidence.  From what I remember of the copy I read, the cover featured a shirtless boy wearing jeans standing in front of a mirror, looking at the large white feathered wings that had grown from his back. Does an Echo Knight fighter's echo provoke an opportunity attack when it moves? Is it possible to use Boot Camp with Windows 10 from an external HDD? I need to run Visual Studio on my MacBook Pro and I need Windows to do that. The easiest and well known way to install Windows on a Mac is by running the Boot Camp app on the Mac and let it do what's necessary. The problem is that I don't want to partition the Internal SSD so the remaining option is to install Boot Camp Windows 10 on an External Drive and boot it every time I need it by plugging in my external USB 3.0 HDD. Is this achievable?