Is there an idiom that means it's possible and not impossible?

Question: Is there an idiom that means it's possible and not impossible? I could only think of "within the realm of possibility", which is a mouthful, and I am wondering if there's any good idiom I might have missed.
Answer: There is the very casual term Doable which is pronounced like my spell checker tells me, 'Do-able"
Comment: This answer would be improved by linking to a good online dictionary that defines this term.


What is the role of non-synaptic plasticity in learning and memory?

Question: Is non-synaptic plasticity (e.g. changes in the spike threshold) believed to play a large role in learning and memory? If so, which roles are these effects believed to play?
Comment: Personally, I would prefer asking such questions like this: "How large is the role of X in Y believed to be (by single or a majority of researchers)?" I.e. not requesting for a yes/no answer, but for an estimate or mean value.
Answer: The answer is yes. Non-synaptic plasticity exists as you can read in "Non-synaptic neuronal mechanisms of learning and memory in gastropod molluscs" by Benjamin et al. and "Compartmentalization of Non-Synaptic Plasticity
in Neurons at the Subcellular Level" by Nikitin and Balaban.
But the effect of hormones such as cortisol may also have an effect.
Non-synaptic mechanisms of regulation and plasticity play a very important role in the brain and its ability to learn in many aspects and at different scales.
A single cell can suffer internal modification that will modify eletrophysiological properties.
Variations of concentration of elements in the CSF also have an effect.
Glia also plays an important role.
So, the brain is a very complex system with a lot of interdependent mechanisms of adaptation, regulation and plasticity. Synapse is just one aspect of it.


2015 STI White smoke

Question: My 2015 Subaru WRX Sti is emitting white smoke from the exhaust. The smoke smells like burning electronics.  When I pull over and open up the hood, I also see white smoke in the engine bay. The smoke is not overwhelming or anything, but you definitely see it. My engine temps are normal according to the temp gauge, i have no engine check lights, the oil indicator is not lit, I don't notice any type of rough idling or irregularities in the feel of the engine. What could be going on?!
Comment: Take it back. Warranties are for this purpose.
Comment: is your engine oil or your coolent levels dropping?
Comment: White smoke would be Ethylene Glycol - avoid breathing it. Odd that you are getting it in engine bay. Perhaps you have a radiator hose, connector, or pipe leak and your engine is breathing this spray?
Comment: Another thought: Some coolants fluoresce under UV light - get yourself a UV torch and you would easily see coolant leaks (if your have fluorescent coolant).
Answer: It sounds very much like you've blown a head gasket. Even with a new vehicle such as yours, this is not unheard of. There are only two ways you'll get white smoke that I'm aware of, those being a blown head gasket or it sucking up automatic transmission fluid. A head gasket is much more common. I'm sure this thing is still under warranty, so get it down to the dealership and have them fix it.
EDIT: I guess you could also have a leak in the cooling system somewhere it mates up with the intake tract ... this would be better than a blown head gasket, but is still not good.
Comment: I'd suspect the turbo before the headgasket.
Comment: Most likely seals on the shaft in the turbo, yes.

2015 STI White smoke


Is it okay to put baking powder in Yorkshire Pudding batter?

Question: It's just that, the first time I tried, they didn't rise as much as I thought they would. would baking powder help?
Comment: I upvoted the answer below because it is all about the heat, could your oven have been quite cold or opened frequently? I usually preheat the muffin tray with a small amount of vegetable oil in each until it is very hot. Then add the mixture quickly before placing back in the oven. The yorkshires are usually massive.
Answer: Yorkshire puddings rise because of the eggs in them. This means that the mixture for you Yorkshire puddings needs heat to rise So if your oven is not hot enough, they won't rise as much as you want. So here are some tips:
-make sure your oven is hot before putting your puddings in
-Don't open the oven while cooking your puddings
-I always pre heat the muffin trays before I use them.
So you put your mixture in a hot muffin tray (or something els you use), put the hot muffin tray in a hot oven, and don't open the oven anymore before the cooking time is over. So I won't use baking powder, I first try it by making sure the heat is there.
Note that of course every oven is different and so you might need a couple of time before have the right temperature. Also I recommend this site for more information about Yorkshire puds: http://www.hub-uk.com/tallyrecip03/recipe0124.htm
Comment: It's the tiny trapped air-bubbles in batter that expand exponentially and are locked in by the egg going solid. Very good suggestion here about the heat -expand before getting cooked. Also can look at incorporating more air to start if results still not as wished.
Comment: +1 - hot fat is the absolute no. 1 factor in a well-risen Yorkshire Pudding in my experience. I heat mine for at least half an hour.
Comment: Although this is good information, it really isn't answering the question. There's [already a Q&A about getting Yorkshire Puddings to rise](http://cooking.stackexchange.com/questions/2582/how-do-you-make-yorkshire-puddings-rise-reliably?rq=1), and it already has all of this information. This answer doesn't address whether or not it is appropriate to add baking powder and certainly doesn't explain why, except to dismiss it as "I don't/wouldn't do it".
Answer: I thought I would try adding baking powder to see if my usually really good Yorkshire puddings would rise any more but no batter went like light cake mixture was a waste of time will stick with my old recipe. If having trouble add another egg I always use 2 and not the recommended one and they are brilliant. Don't know why I messed around
Answer: I use a mix from a cash and carry for yorkshire puddings for my pub sunday lunch service (it's as cheap as buying the ingredients separately), to which you just add water.  It has bicarbonate of soda in it as a raising agent.  The puddings are OK, but not brilliant.  Last week I used my emergency pack of Aunt Bessies mix, and the puds were amazing.  These are the ingredients list:
WHEAT Flour, Dried EGG, Skimmed MILK Powder, Raising Agent (Sodium Bicarbonate), Salt, Sugar, Potato Starch, Emulsifiers (Mono- and Di-glycerides of Fatty Acids, Lacto Glycerides, Propylene Glycol Esters of Fatty Acids), Dried Glucose Syrup, Maltodextrin, Stabiliser (Diphosphates).
So it seems that bicarb is commonly used in prepackaged mixes.
Comment: Wouldn't it be wild if you made them from eggs, milk and flour.
Answer: Don't use baking powder in your mixture. It's an absolute no no, the rise rise LESS and have a cake type texture
Comment: Welcome to Seasoned Advice!  Your answer might be improved by explaining why exactly it's an "absolute no no."  The OP actually implies that he/she wants a greater rise, so simply saying not to use it and that less rise is better doesn't actually address the question.


Lightning Component in List View

Question: I know I am asking something crazy but just wanted to know has anyone ever tried to call a lightning component into the standard list views of any object. That is suppose I have a list view as 'All Accounts' on Account. So is it possible to call a lightning component into it.
Answer: It looks like you're looking for this idea, or, stated differently, no, you can't currently do this. I believe this will probably be in a later release, though we don't know when that might be.

Lightning Component in List View


Why must the gradient vector always be directed in an increasing direction?

Question: I don't understand why it is not possible for some function, say for example $f(x,y)$, to not have some point where the partial derivatives combine to a gradient vector that points in a decreasing direction. Why must it always be negated to get a decreasing direction vector?
Answer: Intuitively, $f(x + \Delta x) \approx f(x) + \langle \nabla f(x), \Delta x \rangle$.  (I'm using the convention that $\nabla f(x)$ is a column vector.)
So if $\Delta x = \epsilon \nabla f(x)$ (here $\epsilon > 0$ is tiny), then
\begin{align*}
f(x + \Delta x) & \approx f(x) +
\epsilon \langle \nabla f(x), \nabla f(x) \rangle \\
&= f(x) + \epsilon \| \nabla f(x) \|^2 \\
&\geq f(x).
\end{align*}
So when we move a bit in the direction of $\nabla f(x)$, the value of $f$ increases.
Answer: It's not obvious:
Consider the function
$$f(x,y):=\cases{0&$\bigl((x,y)=(0,0)\bigr)$,\cr
x+y-{4|xy|^{4/3}\over x^2+y^2}&(else) .\cr}$$
Then $f$ is continuous at $(0,0)$ and $\nabla f(0,0)=(1,1)$, but
$$f(t,t)-f(0,0)=2t-{4|t|^{8/3}\over 2t^2}=2|t|^{2/3}\bigl(|t|^{1/3}{\rm sgn(t)}-1\bigr)<0\qquad(0<|t|<1)\ .$$
This shows that $f$ is actually decreasing in the direction of the gradient.
Now the considered $f$ is  not differentiable at $(0,0)$, and the gradient defined via partial derivatives exists only by coincidence. For any $f$ which is actually differentiable at $(0,0)$ one has
$$f(x,y)-f(0,0)=\nabla f(0,0)\cdot (x,y)+o(r)\qquad(r:=\sqrt{x^2+y^2}\to0)\ .$$
Now, if $\nabla f(0,0)=(a,b)\ne(0,0)$ and you choose $(x,y):=(ta,tb)$ with $t>0$ then
$$f(ta,tb)-f(0,0)=t(a^2+b^2)+o(t)=t (a^2+b^2)(1+o(1))\qquad(t\to0)\ ;$$
and therefore $f(ta,tb)-f(0,0)$ is $>0$ for sufficiently small $t>0$.
Answer: I prefer to explain that is slightly different way:
Actually we define gradient to be always pointing to to the maximum increasing direction! take look at the following:
Consider a function $f(x,y)$, then it's full derivative is:
$df(x,y)=\frac{\partial f}{\partial x}dx+\frac{\partial f}{\partial y}dy=\left(\frac{\partial f}{\partial x},\frac{\partial f}{\partial y}\right)\left(dx,dy\right)=\left(\frac{\partial f}{\partial x},\frac{\partial f}{\partial y}\right)\vec{dr}=\left\Vert \left(\frac{\partial f}{\partial x},\frac{\partial f}{\partial y}\right)\right\Vert \left\Vert \vec{dr}\right\Vert \cos\alpha$
so if we consider for simplicity that $\left\Vert \vec{dr}\right\Vert =1$ finaly we get that:
$df(x,y)=\left\Vert \left(\frac{\partial f}{\partial x},\frac{\partial f}{\partial y}\right)\right\Vert \cos\alpha$
So because cosine function is always less or equal to one , we see that the first term is the maximum possible value for our function increase (because that correspond to $\alpha=0$ ) thus if we define this first term as the length of some vector and we name it gradient, then this vector will point out to the direction of maximum possible increase of our function $f(x,y)$.
Comment: I just rewrote the left hand side as a scalar product of two vectors $\overrightarrow{a}\overrightarrow{b}=(a_{x},a_{y})(b_{x},b_{y})=a_{x}b_{x}+a_{y}b_{y}$
Comment: Can you please explain this notation on the right ? ∂f∂xdx+∂f∂ydy=(∂f∂x,∂f∂y)(dx,dy)
Answer: Intuitively:

if the function is decreasing in one variable, then the partial derivative is negative, so the component vector of the gradient for that variable points in the negative direction - which means increasing function value.
if the function is increasing in one variable, then the partial derivative is positive, so the component vector of the gradient for that variable points in the positive direction - which means increasing function value.

=> Doesn't matter how the function profile is, the gradient, by definition, points in the increasing direction.
Comment: I don't understand how you started with "the function is decreasing in one variable" and ended up with "which means increasing function value". If you're assuming the function is decreasing in one variable, how is it possible the function value is increasing?
Comment: f(x,y) is decreasing in x, so the function decreases as you move forward in x.
But because the partial derivative with respect to x is negative, the x-component of the gradient points towards origin (move backward in x)
- in the direction which makes f to increase.
Answer: Here's another way to look at it: Define $g_v(t) = f(tv)$. Then $g'_v(0)$ represents the rate of increase of $f$ as we walk in the direction of $v$ from $0$. But we can use the chain rule to compute that $g'_v(0) = v \cdot \nabla f(0)$. Looking at the expression $v \cdot \nabla f(0)$, we see that among all unit vectors $v$, the maximum occurs when $v$ points in the same direction as $\nabla f(0)$. We also see that it's at the minimum when it points in the opposite direction. The key to all this is that $f$ be differentiable.
Answer: The rate of change of $f$ in a given direction of a unit vector $\vec u$ is given by the directional derivative $D_u f$,
where: $D_u f = \left\lVert \nabla f \right\lVert \left\lVert \vec  u \right\lVert cos (\theta)$ , for instance, $\theta$ is the angle between $ \nabla f $ and $\vec u $. Therefore $D_u f$ is greatest when $cos(\theta)=1$, and this is when $\theta=0$ and $\vec u $ has the same direction as $ \nabla f $.


How do I measure the saturation luminance?

Question: This question discusses how to measure the dynamic range of a camera.
How can I measure the saturation luminance? A complete example would be most appreciated.
Answer: The saturation luminance is the brightness level above which pixels stop recording unique values and instead record the same maximum value (which is often interpreted as pure white).
You can find the saturation luminance by taking images of increasing brightness until the images start to come out pure white. You can increase brightness either by changing the lighting, or the shutter speed / aperture value.
The saturation luminance is only meaningful however when you also know the luminance at which noise dominates the signal. The ratio of these two figures is your dynamic range.
From your other questions it seems like you're trying to measure the dynamic range of a phone camera. This is going to be very difficult unless you have software to control the camera parameters (namely shutter speed, I assume the aperture is fixed), or have a well calibrated lightsource.
Comment: I am trying to measure the dynamic range of a phone camera. Now i have assumed the aperture fixed and known the shutter speed,but i cannot calculate the dynamic range(namely i cannot calculate the maximum luminance)
Comment: @pealse You need to calculate both the maximum and minimum luminance, which means you have to have some way of controlling the light entering the camera. Why do you need to know the dynamic range? If it is for some scientific purpose, if so you might be able to contact the manufacturer of the sensor for a datasheet. Otherwise you will need either shutter control or a calibrated lightsource.


Are there instances of 'i' meaning 'and' in Spanish?

Question: I know 'y' and sometimes 'e' but is 'i' ever used and in what cases or countries? Is that conflation with Portuguese?
Comment: However, I find some references in old books that may suggest that it was used instead of _y_ in Old Spanish.
Comment: fedorqui: it would have been quite rare, though. Although *⁊* was the preferred form throughout the 15th and 16th century, when otherwise written out, it was fairly universally either *e* (15th century) or *y* (16th).  The use of *i* would be a fairly extreme outlier, because one would actually expect *j* (the letters *i* and *j* still hadn't fully split their function yet)
Comment: No.  But it is used in Catalan and Mirandese.  Portuguese uses *e* always.
Comment: Thanks; that's pretty much what I thought and confirms pretty much my SusPicions About the people e-Mailing.
Comment: Andrés Bello proposed a spelling reform which actually had some effect in South American countries. Some others proposed revised spellings independently, e.g. Manuel González Prada in _Pájinas libres_. However, during 20th those attempts were abandoned in favor of what RAE/ASALE dictates. That's a relative new event, though
Answer: "i" is not correctly used in Spanish as "and" in any case. The only variation of "y" is using "e", when the following word starts with "i".


Stubs and drivers in integration testing?

Question: What are stubs and drivers in integration testing and when and how are they used?I know it comes under top down and bottom up approach respectively but I would like to have a real technology scenario for understanding it more clearly.
Answer: from http://www.allthingsquality.com/p/testing-terms-glossary.html
Driver
A software component or test tool that replaces a component that takes care of the control and/or the calling of a component or system.  [ISTQB]
Stub
A skeletal or special-purpose implementation of a software component, used to develop or test a component that calls or is otherwise dependent on it.  It replaces a called component. [IEEE]
Comment: And here is link to ISTQB http://www.istqb.org/downloads/finish/20/137.html glossary of terms
Answer: That's what Google's tester have to say about it
They talk about dummy values being passed to satisfy API requirements, stubs that replace real objects but returns hard coded values and smarter objects like mocks and spies.
Comment: Very helpful! Can you provide some context for your link? From Help section: "Links to external resources are encouraged, but please add context around the link so your fellow users will have some idea what it is and why it's there. Always quote the most relevant part of an important link, in case the target site is unreachable or goes permanently offline."
Answer: Others have given excellent definitions. I will try to give an example then.
Imagine you have an online shop. The shop has at least two tiers: frontend (GUI) and backend.
You may want to control and verify behaviour of the system on two levels: frontend or backend. On a frontend level you would replace an end-user with a driver that would send requests to the shop Web site. Possible technology would be WebDriver (previously called Selenium), which makes me even clearer why they called this technology this way. On the backend level you would replace frontend with another driver that would call backend services directly. For instance, if your backend exposes REST API, the driver would be some REST client, for instance Jersey or Apache HTTP client in Java world.
We haven't discussed a stub yet. Imagine the shop relies on some third part services responsible for credit card transactions, e.g., MasterCard or PayPal. It would be quite expensive to perform all of the tests with their services involved. Therefore, you can replace PayPal service with a stub, i.e, mock it. If PayPal service exposes SOAP interface, a possible implementation would be to create a fake SOAP Web service that could handle requests coming from the shop backend and respond with fake responses.
Note, for the above illustration I treated a mock and a stub patterns as same thing, neglecting a slight difference between them. The difference is about whether responses of a stub/mock are hardcoded (stub?) and predetermined or rather configurable within your test (mock?). I never remember which is for mock and which for stub. And I really don't care much as there are situations where both approaches can be mixed together, e.g., you may record some of stub/mock requests and responses (e.g., hardcoded SOAP messages), but make configurable only part of them, e.g., transaction balance number.
Answer: Martin Fowler has excellent summary of Test Doubles terminology:

Dummy objects are passed around but never actually used. Usually they are just used to fill parameter lists.
Fake objects actually have working implementations, but usually take some shortcut which makes them not suitable for production (an InMemoryTestDatabase is a good example).
Stubs provide canned answers to calls made during the test, usually not responding at all to anything outside what's programmed in for the test.
Spies are stubs that also record some information based on how they were called. One form of this might be an email service that records how many messages it was sent.
Mocks are pre-programmed with expectations which form a specification of the calls they are expected to receive. They can throw an exception if they receive a call they don't expect and are checked during verification to ensure they got all the calls they were expecting.

Based on book http://xunitpatterns.com/ : http://xunitpatterns.com/Test%20Double.html
Comment: Thank you for the answer but can you  elaborate about stubs and drivers alone with a integration test scenario.
Comment: I created a fake Web service that my system calls. Imagine this Web service can respond with messages previously recorded, but part of this message is configurable from the test. Is this a stub (answers care canned) or mock (part of the answer can be pre-programmed)?
Comment: it is a mutt :-)


What is wrong with my first layers?

Question: I just assembled a Prusa i3 MK3 and went through the calibration process, but when I print the first layer doesn't look good and my prints come unstuck from the bed. I think it might be Z height but this was as high as I could put the probe without the paper moving on the calibration test. The layers after the first few look good but then the print either warps or comes unstuck and moves.
Comment: Use a little more temperature.
Answer: Judging by the images you posted in your question, the first layer distance is too far away from the bed for the current filament flow.
This could either be related to:

having an offset on the first layer like a height correction in the slicer,
an incorrectly levelled (read height adjusted) bed, (you did the paper test correctly, so this is probably not your problem, it is mentioned for completeness)
under-extrusion

slicer setting not correct, e.g. filament diameter or flow modifier not 100 %
incorrectly calibrated extruder

Your most likely problem is under-extrusion. It would be advised to calibrate the extruder: How do I calibrate the extruder of my printer? and check the slicer settings.
Comment: plus one edge is extra far
Comment: Is 'live-Z' adjustment relevant here? Isn't there also a built-in calibration gcode?
Answer: I used the live-z adjustment feature and set it to +0.150 and now my prints look much better.
Comment: You are running +0.150?  I am running more like -0.500.  It all depends on the position of the probe.  That live Z adjustment is important for good printing.  From the pictures, I would be inclined to make it smaller (toward zero or negative).

What is wrong with my first layers?


Is this question off topic?

Question: This question: What are the name and origin of the woodworking style used for this wooden cabinet with rounded features? is getting downvotes and comments as off topic. The question is for help in identifying a historic style, not wood types or opinions.  Please correct me if I am wrong.
Comment: I was just about to come here to ask the same question. I'd assumed identifying antique furniture was off topic, similar to how identifying species of wood is off topic. But perhaps not! Thanks for opening this question.
Answer: As currently written, the question is asking for the origin and history of this particular piece, so it wouldn't be a good fit for this site for various reasons, including the following:

It would likely require significant back-and-forth discussion
The answer is not likely to be very useful to other visitors of the site
It may be incredibly difficult to identify just from photos, without being able to handle it and examine it closely, similar to wood identification questions

If the question were reworded to ask for identification of the general woodworking style, that seems like it may be in-scope, particularly if the features can be described in the title of the question.

Is this question off topic?


For a fantasy world, what word can I use instead of "human" in order to include elves, dwarves, etc.?

Question: I've been creating this fantasy world where many different races coexist, so most aren't human. I'm trying to write all the worldbuilding details down, and I'm stuck on a phrase "She is the goddess who blessed [redacted] with (...)". So, I can't say "humans", because there are also other creatures such as elves, dwarves, orcs, merfolks, etc. and they're all more or less humanoid, but not human, and saying "beings" or "beasts" sounds dehumanizing though, as if I was talking about animals. I'll be thankful for all suggestions haha :)
Comment: Featherless bipeds?
Comment: Miserable piles of secrets?
Comment: In a sci-fi setting, "sapient" is a good option.  But it really doesn't feel right in a fantasy world.
Comment: Or use religion... sons of Adam, daughters of Eve has been used (by C.S. Lewis), children of... what is the name of that goddess? You'll just have to redo your sentence a bit to make it work...
Comment: This reminds me a bit of this discussion: https://rpg.stackexchange.com/questions/176450/is-there-an-alternative-word-to-be-used-in-place-of-humanoid
Comment: I think 'living beings' is very inclusive, but maybe it includes too much.
Comment: Anecdotally, I'm watching a show now actually where they use "mankind" for exactly this. Humans are human but mankind is all the collected races.
Comment: For what it's worth, in the Shadowrun universe (sci-fi fantasy), they call it metahumanity sometimes. Edit: Metahuman is also used in DC Comics to talk about super powered human-beings though.
Comment: "The thinking races"?
Comment: maybe if you have a narrators voice; make up a name for the "humans" and have the narrating voice say "the bidgeybandy are, as a species, much the same as yourself, dear read" or similar
Comment: There is question and answer on another SE section: See https://english.stackexchange.com/questions/360824/how-to-call-something-a-creature-looking-like-a-human-but-which-isnt
In short they used "anthropoid", if you insist on not using human[...].
Comment: "I think therefore I am" ? 8)
Comment: @Hearth brilliant!  we also have humanlike, monkey(?),  uhm.. humanrace? maybe make up a word?  humankind instead of "man"kind ?
Comment: Humanoids ? Seems a bit odd though.
Comment: @Itération122442 Yea, agreed. :)
Comment: I dont have rep enough to post an answer, but can't you somehow explain in a inclusive language(if there is no direct `word` for it?)  like.. Instead of saying `all (word here)`, like *all people* - to include elfs,etc,etc, maybe you could **do something like this?** `All elfs/humans/creature_race1/creature_race2... (do this...)` or something?
Comment: sorry writing is NOT my front, so sorry!  but wanted to share that ; either way. Have a good day and wishes from Sweden!  ^_^
Comment: Does it matter to you that "human" basically means 'Earthling' and so in your world does necessarily include elves, dwarves, orcs, merfolk, etc?

Does it matter that 'humanoid' is a modern term formed from but in no way contributing to 'human'?

I commend Google and every other search engine should show you the same results.
Comment: @JohnGordon Yea! :)
Answer: Honestly, it sounds that the best word for the inhabitants of your world - humans, elves, dwarves, orcs, merfolk, all together - would be...
People.
Comment: Or "the peoples"
Comment: @DarrelHoffman Tolkien called humans "Men" (capitalised) in his books. Which, if I recall right, clashed with the fact that he didn't capitalise Elves, Dwarves, Orcs or Hobbits. There's also the detail that the number of women in Middle-earth seems to average about one per country.
Comment: J.R.R. Tolkien agreed!
Comment: @Davislor Though he didn't use the word "human" to refer the specific race either - they were called "men" regardless of gender...
Comment: I'm thinking of, "Learn now the lore of Living Creatures! / First name the four, the free peoples." Tolkien did also use "Men" in the old-fasioned, epicene sense, but I don't think the question is about that.
Comment: wait, can;t creatures be used? or humanoid..? :P sorry I don't know.
Comment: this is a great yet *hilarious* answer. (I mean it! It's great!) :) thanks.
Comment: Tolkien used "Free Peoples" to refer to humans, hobbits, Elves, & Dwarves, which has a nice ring.
Answer: The word "mortals" would probably be a good fit in this context. "She is the goddess who blessed mortals with..."
Other words that could work in this context might be: living beings, entities, intelligent life, sentient life, flesh and blood, etc.
If this world has a specific name, such as "Terra", you could name them the "Terrans".
If these people are the descendents of gods in some way you could call them the Children of the Gods, the Children of the Divine, the Divine Descendants. You could also name them after the goddess herself. For real world example the Athenians named themselves after Athena, goddess of Wisdom.
You can add to the worldbuilding by tying the name to a creation myth.
Ex-A thousand years ago the Wolf Goddess lost a tooth. It fell from the the Heavens and landed on the Earth, becoming a mountain. The people believe their life force is tied to this Fang.
So they call themselves the...well, there are a lot of things they could call themselves.
The Children of the Fang. The Fangs of Heaven. The Sky Fangs. The Celestial Fangs. Etc.
There are lots of possibilities.
Comment: @komodosp In _most_ settings, 'mortals' is limited to what most people would call, well, 'people', with the implication being beings with at least human-equivalent intelligence who are specifically not gods.
Comment: But presumably "mortals" would include dogs, fish, trees, etc. ? (As well as Terrans?)
Comment: This might be a problem if one goes with the trope that elves are immortal.
Comment: @infinitezero Elves are usually a different type of immortal than what is meant when gods reference mortality. Elves are the type of immortal that means they do not die of old age, but usually can still be killed. Gods are usually the type of immortal that means cannot die at all. So in the context of deities, "mortal" means those creatures that can perish, which would include the typical elf. That said, this word choice would still make an amusing oxymoron that the author may prefer to avoid.
Answer: Her Creation. This would include sentients (humans, elves, dwarves, etc), animals, vegetals, minerals, the sky above, the sea on the horizon, the ground below, everything. That obviously assumes a myth of creation where the goddess created everything, which is pretty typical in religion.
Her Children. This would typically include sentients, possibly animals as well, conceivably anything else depending on the core beliefs of the religion (e.g. trees are sacred, so trees are children of the goddess too). That largely assumes a myth of creation, although they could be adopted children.
Her People. This would typically include all sentients. This does not assume a myth of creation, it could just be the people the deity rules over.
Her Peoples. This is like the above, except it allows you to mark a distinction between all your sentients, on the basis of species, culture, or whatever else. This may be prefered by groups who consider themselves superior to others.
Naturally, you can use another pronoun than "Her".
Answer: A few examples of how other speculative fiction has addressed this:

X and Y:  If there are few enough groups of sapient beings in your world, you can just have a stock phrase that enumerates them.  In The Elder Scrolls setting, the phrase "men and mer" is used frequently to refer collectively to all sapients (men being humans, mer being the setting's various kinds of elves and elf-derived folk like orcs and khajiit).  Strictly speaking, argonians are sapient and neither men nor mer, but this is often ignored.
Sophonts:  Used frequently in sci-fi to refer collectively to sapient beings, this will come across as a reference to its use by other writers like Poul Anderson and Vernor Vinge, but that could be a good thing depending on how you want your setting to feel.
Kith:  Used in the Pillars of Eternity games' setting to refer collectively to sapient peoples.  Derived from the English word meaning something like "friends, relatives, acquaintances, neighbors".
Bodies:  Used in D&D's Planescape setting to refer to all embodied sapient beings.  You probably don't want to actually use this one, since it does the opposite of emphasizing their personhood, but in the setting, that's a feature, not a bug - it emphasizes both how little the planar travelers of Sigil care about "superficial/cosmetic" differences between different types of people, and also that they don't tend to hold individual lives in high regard.  Take this as inspiration for how the word your setting uses for this can emphasize to the reader how people in your setting tend to think about other people and the value of lives.
Answer: What about "folk"? It's a commonly used synonym for people, and it sounds suitable for a typical fantasy setting. The one downside is it sounds a bit informal for a religious document, but I think you can get around that if you use it consistently to differentiate from "humans" as just one type of "folk."
You could also use it as the root for a coinage. "She blessed all the hainfolk, the elves, dwarves, humans and fairies."
Answer: Are you trying to get at humanoid? That would be critters that are basically similar to humans. Elves, dwarves, orcs, hobbits, etc. Even such things as dryads, giants, and some things I've forgotten just now. A head on top of a body, with two arms and two legs, a face, more-or-less mammalian, some hair of some kind, etc.
The border between humanoid and otherwise is somewhat fuzzy in fantasy and science fiction. There will be disagreement on mermaids (because of the fishy bottom), werewolves (because of the phase with four legs), vampires (because they are undead), and robots (because they are not biological). Undoubtedly you can come up with other cases that are difficult to categorize.
Presumably any other species besides humans will have something in their language that does the same job. Elves, for example, will have some word that means "elf form."
Comment: Even if it's technically apt, *humanoid* would be pretty jarring in a typical fantasy setting.
Comment: @WilliamMartens: I mean 'apt' in the sense of the [ordinary English word](https://en.wiktionary.org/wiki/apt), i.e. 'suitable', 'fitting'.
Comment: @AustinHemmelgarn No, it still applies when translation convention is in place. Translation convention covers tone, style and connotations as well, not just the strictly technical meaning of words.
Comment: @PLL - especially if "human" is just another race like "elf", "orc", etc. I am not sure the others would appreciate being referred to as "humanoid"....
Comment: @PLL with 'apt' you mean.. what? (I think of the util in linux `apt` for software management)
Comment: @PLL That only fits if the writer is assuming that the whole setting speaks English (or real-world languages), which is rarely the case. Part of the conceit of a typical fantasy setting is that the reader/viewer/player is magically able to understand what is meant by everyone there, even though everyone there is speaking a completely different language.
Comment: Humanoid assumes humans were first. Why not orc-oids? Orcs aren't human-like, humans are orc-like.
Comment: @MonkeyZeus  It's *SO* hard reading all the way to the bottom of a three paragraph post.
Answer: Maybe the answer is already hidden in your question? How about creatures?
Collins has:

You can refer to any living thing that is not a plant as a creature, especially when it is of an unknown or unfamiliar kind. People also refer to imaginary animals and beings as creatures.

That should include all the elves, dwarfs, orcs, etc.
In your case you could write: "She is the goddess who blessed all creatures with the gift of language/..."
Answer: You're looking for something formal and solemn, but there have been a lot of funny ones over the years. Most famously, the story about how Plato defined human as, "featherless biped," so Diogenes plucked a chicken, and the Academy added, "With flat nails."  That particular one doesn't work here, though, if there are mer-people.  Or maybe that's what they call everyone else.  "Naked apes," is another.
Answer: Earthlings, as opposed to divine beings.
Comment: "Earthling" only really works if the planet in your fantasy setting is still called "Earth", which probably isn't the case, but using the setting's [demonym](https://en.wikipedia.org/wiki/Demonym) ("Earthling", "Martian", "Alderaanian", etc.) is a pretty good suggestion.
Comment: this I totally agree with!  earthlings ! :D **brilliant**
Comment: note that in many languages the word for "human" (sometimes later specialised to "man" specifically) literally means "earthling" (not in the sense of someone from Earth, but someone from the earth/the ground). Human is an example of this (from Latin humus "ground"), but also Irish duine, Welsh dyn, Latin homo, Lithuanian žmogùs, and the Old English guma (surviving as the groom in bridegroom) all from the same Indo-European root
Answer: According to Wikipedia, the word "Human" refers to all species in the Genus "Homo" of which only Homo Sapiens are extant... however, over the course of prehistorical life, there were possibly 18 different species of within the "Homo" genus.
It could be that your fantasy species are all of the "Homo" genus but may not be of the "Homo Sapien" species.  This would require you to get creative with latin names, but you could say something like "The term "humans" covers all creatures within the Homo genus, including the Common Human (H. sapiens), Elves (H. alfitis), Orc (H. orcneas), Dwarves (H. dhreughitis) and Merfolk (H. maritimus)* as well as the hybrid offspring of different species of humans.  Often, to distinguish the collective genus of humans from Common Human, the term "humanoid" will refer to any member of the Homo genus, while "Human" will refer to Common Human but all terms are valid in the academic world."
In Law, the word "Human" is rarely used as modern law already deals with non-human legal entities, such as corporations, governments, and other legal entities that may not be human in nature.  Thus the law will usually refer to "legal persons" which covers a singular individual, or collective entity.  More archaeic but terms would refer to "people" such as in the U.S. Constitution, where "people" referred to the body of ordinary citizens in all instances of use in the original document AND the Bill of Rights.  This distinction in law that ignores biological humanity already makes the law and legal rights of non-humans much easier to protect, since you already do not have to be a human to participate (for example, the U.S. government routinely sues for violations of civil law, and in general legal theory, only the legal entity of "the state" may bring up criminal charges against a criminal defendant (only a legal entity who is actually a human may be penalized with jail time, but all legal persons can suffer fines for criminal behavior).
This can also be an expression of language differences, as happens already in real life where languages may not use the same words when describing nationalities.  For example, in the English Language "American" refer to someone or something that is from the United States, however, in most of Spanish speaking, the translated word of "American" refers to someone or something that is of the American Continents (North America, Central, Caribbean, and South America) and "estadounidense" refers to those who are from the United States of America (It's literal translation is United Statesian).  On the other side, in the English-speaking world, the word "German" is used to denote people or things from Germany, but in the German Language, the equivalent word is "Deutsh", and the equivalent country is "Deutschland".
Similarly, in your setting, each race could have a race centric name for humans in their own language and their own language uses their race as the basis for all others, so the elvish word for "humanoid" is effectively "elvenoid" and the Orcish word for humanoid is "Orcoid".  Since English is a human language, when elves and orcs speak English, they would use humanoid because that is the correct term.  One problem bound to arise is that a human suffering from "Dwarfism" is still referred to as a Dwarf in real life, so you might have to work with a member of the actual Dwarf species being offended by this, but the easy work around is that the stereotypical Dwarf culture would not see anything associated with a Dwarf as an insult.
Depending on how your setting works, the "human" species might cover some non-human looking things.  In D&D lore, there are several unique races that are human but have some very non-human features (most famously, the Tieflings are typically born to human parents, who's family line at one point interacted with demons or the abyssal plain from which demons come from... and this could be several generations from that interaction and the child's birth.  It's explicitly stated that Tieflings need not be the product of a sexual union between a human and a demon, so it could be some peoples are true humans, with some magically induced differences in phenotype.)  There may still be other species that may be further removed from humans than the genus level but still retain humanoid features (in some lores, when they appear, gnomes are humanoid, and in others they have no relations to humans (being minor fey creature).  Additionally in many fantasy systems, one can be a standard playable race but not be a "humanoid" with the option to play goblinoids (which includes goblins, hobgoblins, and Bugbears) and the distinction between humans and goblinoids is such that the rules system does give them immunities to mechanics that only effect humanoids.  In real life, Humans are one of 8 extant "Great Apes" or Hominidae, which include the Homo genus (Humans), the Pan genus (Chimpanzees and Bonobos), the Pongo Genus (Three different species of Orangutan) and the Gorilla Genus (Two separate species).  It could also be some human-like races are not Homo but would fall into a broader "Great Ape" category.  All animals in the Hominidae represent some of the most intelligent animals in the world, even if you don't count the bell curve wrecker that is Humans.
Answer: There are any number of ways you can express the concept, including the various answers already presented, depending on what you're trying to convey. There are a few questions that affect which one fits best.
What feature do all of the included species have in common? From the list you've presented - a classic short-list of fantasy humanoids - there are a couple of features, but the important one is this: they're all intelligent, to some degree or another. All of them are capable of rational thought, even if the orcs (and probably many of the humans, if we're being honest) generally aren't very good at it. Technically, in the jargon, they're all sentient or even sapient.
What is your speaker's target audience? If they're delivering a dissertation at a conference then technical jargon is the norm, but anywhere else it's a bit weird. In most cases "sapient species" is not only out of place, it's just going to confuse most people. It carries a tone of pretentiousness that even those who understand it will likely be turned off by.
So let's tone that down a little. In a lot of fiction, both fantasy and scifi, people don't talk about species. Instead we tend to use the (technically inaccurate) word "race" to describe other people, even if we don't share compatible genetics. OK, in a lot of fantasy fiction hybrids (half-orcs, half-elves, etc.) are fairly common, so perhaps "race" is technically accurate in those cases, but you get the point.
So rather than jargonizing, let's settle for more common speach: the intelligent races.
This encapsulates the important parts without "dehumanizing" (for our meaning of the word; perhaps "depersoning" might be a better fit?) anyone. Using "race" implies that there is a fundamental commonality between all of the included people; whether or not we can breed with them, they're just another type of person who happen to have radically different phenotypes. The elves are a race of tall, delicate people who live a long time. Orcs are a race of strong, brutish people with green blood and emotional control problems. But both are people in those descriptions, not animals, not monsters and definitely not things.
Answer: In a world that contains many creatures such as humans, elves, dwarves, orcs, merfolks, etc., there will inevitably exist many, many words describing different subcategories of creatures, depending on how inclusive or how racist (specist?) the speaker is.
I don't think this topic can be dodged realistically.
For instance, perhaps a common belief amongst some people is that humans and elves are superior to other creatures. Another common believe amongst some other people is that humans, elves and dwarves are superior to other creatures. Another common belief is that hybrids (like merfolk and werewolves) are only half-way between humans and lowly animals. Perhaps a common belief amongst many people is that orcs are inferior to all other humanlike creatures. Perhaps another common belief is that creatures with magical powers, such as elves and merfolk, are superior to creatures without magical powers, such as humans and dwarves.
Every group which believes that some particular subcategory is superior will have a particular term for that subcategory.
Inevitably, some terms will be ambiguous and depend on who is saying them. For instance, "person" refers to anyone that the speaker considers to be a person, which might or might not include orcs depending on the speaker.
Some other terms will be more technical / scientific, or simply more vivid, and thus will be less ambiguous. For instance, "hybrid" or "taur" refers to all creatures which look half-human half-animal, like merfolk and centaurs. But maybe some creatures consider the word "hybrid" to be offensive, because it suggests that a mermaid would be the offspring of a human mating with a fish, whereas obviously that's not the case (or is it?).
Unless you want to bowdlerise your text, I think this topic and this ambiguity of vocabulary is unavoidable in a world populated by many humanlike species.
Vocabulary that might be useful:

Human;
Sapient, sentient, intelligent, superior folk, elevated folk;
Person, people, folk;
Humanlike, humanoid;
Hominoid, Hominid, Hominin, Hominina, Homo, Homo [Something];
Biped, anthropomorph, anthros;
Being;
Mortal;
Creature;
Children of [insert name of god or planet or land]
Answer: It depends on the reason why you need to use that word.
If you just need it rarely in a general throwaway manner like in your example, without having any need to draw any attention to it, then the word "people" or something similar would be the best choice.
However, if the differences between your sentient humanoids and non-sentient or semi-sentient beasts is an important part of the setting, or if the similarities between your humanoids is an important plot point, then it might be useful to make up a fictional word to use it in your setting.
There are examples for both cases:

Kith, as used in the Pillars of Eternity, is important because the concept of a soul and reincarnation are central to the setting, therefore there is a strong need to differentiate creatures which do have a soul and can reincarnate, from those which can not.

Hnau, in The Space Trilogy from C. S. Lewis refers to sentient beings, even if they live on different planets. Humans are the only hnau they know of before first contact, therefore most of them don't value alien lifeforms and are only loyal to the interests of humanity, not having much issue with the idea of wiping out other species to settle humans on other planets. However, with planets where multiple hnau species live and coexist, they learned to respect other species on the same level as their own species, and they regard members of other intelligent species the same as their own, no matter how greatly they differ.


What is the difference between tissue engineering and 3D bioprinting?

Question: 3D bioprinting is the modified version of the tissue engineering but when we want to describe the both terms, what are the basic criteria or points to make difference between these?
Answer: Tissue engineering is research into ways of organizing cells and cell droplet/matrix structures into a useful form, usually for medical applications. In the near future, tissue engineering could refer to rewriting or genetically modifying cells for a new purpose or to enhance their existing function. Even more into the future and tissue engineering could mean custom-building multi-cell structures from scratch on a computer.
3D bioprinting is the practical or laboratory deployment of the first technology mentioned above - a subset of tissue engineering.
In a nutshell:
Tissue engineering = "Come up with a creative way to arrange these cells and cell structures into something useful".
3D bioprinting = "Use the above-mentioned technology to build part of a synthetic organ".


Not able to use faster shutter speed 1/4000 or faster

Question: I have Nikon D7000 with 18-105 mm lens. One day around noon outside I tried to dial in 1/4000 shutter speed in Shutter Priority mode at 18 mm f/3.5. The exposure meter was telling me my image is going to be underexposed. I tried to increase the ISO to its maximum value but still exposure meter was not balanced. So I am wondering at what combination of ISO and f-stop I can use such or more faster shutter speeds.
Comment: What kind of light were you shooting in? A 1/4000th shutter speed is a VERY small amount of light. Outside of bright daylight scenes,  it is entirely probable that you won't have enough light to get a proper exposure at that shutter setting. Even if you increase ISO, you could very likely be several stops beyond the required shutter speed. If you are shooting at 18mm f/3.5 1/4000th ISO 1600 in post-sunset golden hour, you probably don't have anywhere remotely close to enough light to expose more than a very dark gray frame.... So...it would be very helpful to know what kind of light you had.
Comment: When you say you tried, does that mean you were unable to get the shutter speed to 1/4000?  Could you take a shot.  In shutter or aperture priority I would ignore the meter anyway.  At f/3.5, even on a cloudy day, at 1/4000th you shouldn't have to bump up ISO beyond maybe 800.
Comment: Well I was trying to shoot outside on a bright sunny day. I was totally relying on the meter. May be I can ignore the meter and can try to take some pics at 1/4000 or even way past that.
Comment: How similar is the low exposure warning and the backlight warning on a D7000? Is there any shooting mode where the two could be confused by the operator and the camera refuse to release the shutter if the backlight warning is activated?
Answer:
Well I was trying to shoot outside on a bright sunny day. I was
  totally relying on the meter

The meter is for manual mode.  Ignore it if you're in shutter or aperture priority.
It may blink Lo at you if it thinks it's too dark, or pop up the flash, but just give it a try and see what you get.  You were probably fine to shoot
Sunny 16 Rule says on a sunny day, at f/16, shutter ought to be reciprocal of ISO.

1/250th second at f/16
1/500th at f/11
1/1000 at f/8
1/2000 at f/5.6
1/4000 at f/4 (which is the same figure Johann3s came up with)
Answer: Your exposure gets basically determined by three things:

Aperture
ISO
Shutter-speed

These three properties together determine the amount of stops. There are tables as a general guideline for how many stops you need under certain circumstances. One example is given here.. According to this table, the most common bright daylight setting equals the number 15. On this same page is a table which shows which settings you need to use for which f-stop number.
This table says that for bright sunlight you can achieve 1/4000 at ISO200 F/4.


Do we want a parts-database or parts-library tag?

Question: I noticed that there a lot of questions that mention a "part library", but we don't have a tag like "part-database" or "parts-library" to include those.
We have a set-database tag, but that doesn't seem to fit since parts are not sets.  Am I missing something or is there an opportunity for a useful tag here?
I got started on this while trying to find better tags for jncraton's question.  I don't think we have enough on 3D rendering for a tag that specific yet, but the "parts-database" aspect of it seems worthy of a tag to me.
I prefer "part-database" for consistency with "set-database", but "parts-library" is how people seem to use it and should at least be an alias if not the primary tag.
Comment: I added the part-database tag and created parts-library as a synonym.
Answer: That makes sense to me. I like part-database with parts-library as an alias.


Robots.txt is not found when placed in web root: where to place?

Question: What would be the correct place to put my robots.txt file? In wordpress i was used to putting this in the web root but in EE this doesnt seem to work, when opened in webbrowser i get 404 error.
Answer: Sounds like your htaccess file is rewriting the request and serving it to ExpressionEngine index.php. Ensure you have RewriteCond %{REQUEST_FILENAME} !-f in your htaccess file which will ignore all physical file requests and not ask EE to serve the request.
# Directs all EE web requests through the site index file
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /index.php/$1 [L]

Alternatively, don't have a physical file on the server, create the robots.txt file as a template in the main template group folder. You might need to utilise template routes to remove the template group name.
Comment: thx! that helps alot!
Answer: Very much depends on how your server is set up, but usually it should go in the same folder that you have index.php - which is usually the folder public_html or some such (depending on what server you are using).
If that is not finding it - check to see if you have some .htaccess processing going on: that might mess it up.


Riddle: What halacha is learned from something said by Satan?

Question: Riddle: Name a halacha derived from a statement of Satan.
Answer: The statement is Job 2:4

וַיַּעַן הַשָּׂטָן אֶת יְהוָה, וַיֹּאמַר:  עוֹר בְּעַד עוֹר, וְכֹל אֲשֶׁר לָאִישׁ--יִתֵּן, בְּעַד נַפְשׁוֹ
And the Satan said to God: skin on behalf of skin, and all a man has, he will give for his own life.

The Halacha is that while we may not redeem a captive if the price is too high, an individual is entitled to spend as much of his own money as he likes on redeeming himself (and possibly his spouse).  This is based on the above verse.
  --Tosfos, Kesubos 52a, s.v. והיו.
My understanding of Tosfos is that the verse is describing a reality of human behavior.  Since:

Any normal person would do anything to save themselves

AND

Rabbinic enactments can only be made if most people are likely to abide by them.

THEREFORE:

The rabbis excepted one's self from the "no exorbitant ransom" rule
Comment: Ashkenazi Chief Rabbi Yona Metzger observed that 30-40% of the people Israel releases (in exchange for its own) will go do more terrorist stuff, and that released terrorists have so far killed 50+ Israelis.  On the other hand, he pointed out that the "we get our boys back no matter what" policy is a morale-booster for the troops, and enables them to do maneuvers that they otherwise couldn't.  This generalized pikuach nefesh is a consideration they can (and do) weigh against the Mishnaic enactment.
Comment: How does this apply to the cases in Israel today? What price is considered "too high" to get soldiers back? If their lives are at risk, is that considered a case of pidyon shvuim, or pikuach nefesh?


How can proteins reduce surface tension?

Question: How can the protein lactalbumin reduce the surface tension of water and work like an emulsifying agent in milk?
Answer: I dont know why lactalbumin reduces the surface tension but If you know the concepts of surface tension and surfactants then it becomes easier to extrapolate on that concepts to reach the conclusion why lactalbumin reduces surface tension?
According to HyperPhysics surface tension is the

The cohesive forces between liquid molecules are responsible for the
  phenomenon known as surface tension. The molecules at the surface do
  not have other like molecules on all sides of them and consequently
  they cohere more strongly to those directly associated with them on
  the surface. This forms a surface "film" which makes it more difficult
  to move an object through the surface than to move it when it is
  completely submersed.

And the choesive force is caused by the hydrogen bonds due to the  strong interactions between water molecules

And according to wikipedia

Surfactants are compounds that lower the surface tension (or
  interfacial tension) between two liquids or between a liquid and a
  solid.

This image shows how a surfact decreases the surface tension of a liquid by causing interference in the hydrogen bonds between water molecules

Similarly lactalbumin which has a core hydrophobic group and other functional group such as thiol(Beta lactalbumin) which may interfere in water-water hydrogen bond causing decrease in surface tension.


Can you use a 8 speed Shimano shifter with a 7 speed cassette?

Question: I want to use an 8-speed shifter with a 7-speed cassette.  I saw this question, but I am unsure if this would work, since I believe the spacing is the same between a 7- and 8-speed, but the length is not.
Comment: I have a 7 speed cassette, but the shifters are bad, and looks like there is more variety with 8 speed shifters instead of replacing the wheel or hub.
Comment: If the spacing is the same, then you could, but if you shift too far you'd pull the chain right off the cassette.  If it goes into the wheel, goodbye wheel (possibly).
Comment: Why do you want to do this?
Answer: You can do that, the spacing is the same.
As already pointed, you're going to have a "phantom gear" on your shifter.
If you let gear number 2 on the shifter correspond to gear number 1 in the cassette, you should take care not to press too hard on the lever when you are already in gear 2, since this should overstretch the cable or the lever.
If you let the normal order until gear 7, and have an 8th gear on the lever as an "empty" or "ghost" gear, there is no danger to overstretch anything, but the shifter cable might become too loose, to the point of the housings coming out of their stops.
Anyway, the gear spacing is the same, and there would be any necessary damage in any part, except one of the positions of the shifter not being used.
Also, this could be a good alternative to upgrade the shifter, and only some time later to upgrade the rear wheel.
At last, have in mind that these systems are not in production anymore (as far as I know).
Hope this helps
Comment: @MladenJablanović I am not sure, that is a fact. My answer is based on what me and a lot of friends did when 8 cogs became the new standard: we just started mixing hubs, shifters and derailers of different number of cogs, and everything just seemed to work normally. But perhaps there was some difference, although not show-stopping.
Comment: Sorry, could you clarify on what you mean by "not in production anymore"?  Are you referring to Shimano manufacturing?
Comment: @CarsonReinke yes, I think at least for medium-to-high-end components, everything is 9 or even 10 speed, be it Shimano or SRAM...
Comment: Shimano still makes 8 spd integrated brake lever shifters. Claris line.
Comment: Are you sure the spacing is the same? On [Sheldon's page](https://www.sheldonbrown.com/cribsheet-spacing.html) it says that the pitch with 7-speed is 5mm, while with 8 speed is 4,8mm
Answer: You can't over shift if your rear derailleur is adjusted correctly (the high and low limit screws will prevent it). You will just have a phantom gear – like they say.
Answer: Assuming you have a 7 speed cassette that can be disassembled and not a 7 speed freewheel....the cog spacing (center to center) of 8 spd is 4.8mm, the cog spacing of 7 spd is 5.0mm. Replace the plastic cog spacers of the 7 spd (3.15 thick) with 8 spd spacers (3.0 thick)....readily available on line. This will yield a 4.85mm cog spacing....shifting should be oblivious to the .05mm difference. Lockring should still tighten the starter cog, otherwise get a 1mm spacer and put it under the largest cog. I have revised cassettes both ways (7 to 8 and 8 to 7) successfully.
Answer: It will work but as JackM. states make sure you limits are adjusted precisely.You also have to decide if you want to risk over shifting on the low gear or high side.
Comment: I stand corrected


How to composite live 4K video with prerendered alpha matted footage

Question: I'm looking to take a 4K live video feed, and composite alpha channeled footage on top of the live footage, all in realtime with minimal latency, I then want to display the output on a 4K screen .... Any ideas of the technology and equipment nesasarry to make this happen
Comment: Have you looked in to the software wirecast pro?
Answer: I have a Blackmagic Design DeckLink card which, with bundled software, provides live keying.  I bought that card before they sold a DeckLink 4K cards.  But because they come withe the same bundled software and make the same live-keying claims, I would check that this version first: https://www.blackmagicdesign.com/products/decklink/techspecs/W-DLK-04
You should be able to ingest two channels of 4K video, key it, and output the keyed result in real-time, for $995.  It does require you to have free PCIe card slots in your computer.
An entry level 4K switcher (that gives not only pre-rendered alpha matted footage, but also transitions and chroma key) runs $1,695, and runs stand-alone (i.e., not a card in your computer): https://www.blackmagicdesign.com/products/atem/techspecs/W-APS-04


How is the opening-day price of a stock decided?

Question: I have read the the IPO price of a stock is set by underwriters, who then sell to (typically) institutional and "special" investors.  Once the stock is ready for the stock exchange, who decides what the stock will open at?  And how is the price of that stock determined?
Comment: `More broadly, can someone outline the first-day-of-life for a new stock from time of issue to the time the first shares hit the exchange? Or point me at a reference.` You should ask this as a separate question.
Comment: Related: [Stockmarket: why is the "open" never the same as previous day's "close"?](http://money.stackexchange.com/questions/3765/stockmarket-why-is-the-open-never-the-same-as-previous-days-close)
Answer: When a stock is going to become public there's a level of analysis required to figure out the range of IPO price that makes sense. For a company that's somewhat mature, and has a sector to compare it to, you can come up with a range that would be pretty close.
For the recent linkedin, it's tougher to price a somewhat unique company, running at a loss, in a market rich with cash looking for the next great deal. If one gives this any thought, an opening price that's so far above the IPO price represents a failure of the underwriters to price it correctly. It means the original owners just sold theirvshares for far less than the market thought they were worth on day one.
The day of IPO the stock opens similar to how any stock would open at 9:30, there are bids and asks and a price at which supply (the ask) and demand (bid) balance. For this IPO, it would appear that there were enough buyers to push the price to twice the anticipated open and it's maintained that level since.
It's possible to have a different system in which a Dutch auction is used to make the shares public, in theory this can work, it's just not used commonly.


What is the purpose of "MOSFET driver" ICs

Question: There are dedicated "MOSFET driver" ICs available (ICL7667, Max622/626, TD340, IXD*404.)
Some also control IGBTs.
What is the practical purpose of these? Is it all about maximizing the switching speed (driving gate capacitance) or are there other motives?
Answer: A MOSFET driver IC (like the ICL7667 you mentioned) translates TTL or CMOS logical signals to a higher voltage and higher current, with the goal of rapidly and completely switching the gate of a MOSFET.
An output pin of a microcontroller is usually adequate to drive a small-signal logic level MOSFET, like a 2N7000. However, three issues occur when driving larger MOSFETs:

Higher gate capacitance - Digital signals are meant to drive small loads (on the order of 10–100 pF). This is much less than the gate capacitance of many MOSFETs, which can be in the thousands of pF.
Higher gate voltage - A 3.3 V or 5 V signal is often not enough. Usually
8–12 V is required to fully turn on the MOSFET.
A switching MOSFET can cause a back-current from the gate back to the driving cicruit. MOSFET drivers are designed to handle this back current. (Ref: Laszlo Balogh Design And Application Guide For High Speed MOSFET Gate Drive Circuits.)

Finally, many MOSFET drivers are designed explicitly for the purpose of controlling a motor with an H-bridge.
Comment: There is a third issue: a switching MOSFET can cause a back-current from the gate back to the driving cicruit. MOSFET drivers are designed to handle this back current. ([ref](www.ti.com/lit/ml/slup169/slup169.pdf) p12)
Comment: For PMV19XNEA a logic level MOSFET, with a combined turn-on and rise time delay of approx. 25 ns, can we conclude that a MOSFET driver would not be needed for switching 2 amps at 19V? Typical delay times for the ICL7667 indicate that the driver may even exacerbate the overall delay.
Answer: Yes, it's about maximizing the switching speed by dumping lots of current into the gate, so that the power MOSFET spends the least amount of time possible in the transition state, and therefore wastes less energy and doesn't get as hot.
It says as much in the datasheets of the parts you listed :)

The ICL7667 is a dual monolithic
  high-speed driver designed to convert
  TTL level signals into high current
  outputs ... Its high speed and current
  output enable it to drive large
  capacitive loads with high slew rates
  and low propagation delays ... The
  ICL7667's high current outputs
  minimize power losses in the power
  MOSFETs by rapidly charging and
  discharging the gate capacitance.
Comment: Why not just use a transistor instead? there's ones that can easily handle 1.5A. why get the IC instead of a single transistor?
Comment: @user3033693 because now you need to charge that transistor again. If it can handle 1.5A, it will have a high input capacitance too. To mitigate this, you'll need several stages, and at this point, you know why you use an IC. There also are the other problems mentionned int the other answers.
Answer: If you want to calculate the gate current during switching you can use this formula:
Ig = Q/t
where Q is the gate charge in Coulomb (nC from the data sheet) and t is the switching time (in ns if you use nC).
If you need to switch in 20 ns, a typical FET with a total gate charge of 50 nC will need 2.5A. You can find nimbler parts with gate charge below 10 nC. I prefer to use 2 BJTs in a totem configuration for driving MOSFETs instead of the expensive driver ICs.
Comment: And how do you do the voltage translation for the totem?
Comment: Lately I've had good results using logic level MOSFETs and running the totem on the 3V3 rail. You can also use a BJT for voltage translation if you are ok with the signal being inverted.
Answer: Yes. And another reason is to drive "high side" of the bridge. For this those ICs have an external capacitor and internal oscillator with diode voltage multiplier, so the gate driving output is providing voltage few volts higher than bridge and/or bus voltage.
Comment: Yes - special high side drivers exist **so that the better-performing N-channel devices can be used on the high side of the bridge** as well as the low side.  Otherwise - without a gate voltage above the positive supply rail - a P-channel device must be used there.  There's a point where the superiority of the N-channel devices justifies the additional circuit complexity of this technique.


What size softbox works with a speedlight?

Question: I am thinking of buying a softbox for a speedlight to step up my lighting, while staying within my budget. I have a Yongnuo YN-568EX II speedlight that O intend to use in the softbox. My question is which softbox would be suitable for me, if I wanted to take full body shots? Or can I even do that, given that I have a speedlight, not a strobe and full body shots require large softboxes. Is my speedlight powerful enough to support a large softbox of, let's say, 80x80 or should I go with 60x60?
I'll be highly grateful if you help me out. :)
Comment: Buy them all!!!
Comment: The speedlight will work with any softbox, the questions will be how close it needs to be and what aperture you can use. But in general, to preserve the power of your light, use the smallest size you can. For full body shots you may want to go with a strip box in something like 50 x 130.
Comment: "*staying within my budget.*" but what *is* your budget? Could you live with a DIY solution? Does it have to be portable? You seem to be very confident that you need a softbox, but bouncing the flash into a big white wall might have a similar effect for a much lower price. Did you try something like that?
Answer: You can use a small 9 inch softbox which fits on the flash head or you can also use spedlight diffusers.
You can use your speedlight at full power inside a large softbox also, the only constraint in doing that is the distance or the guide number of your speedlight. In a large softbox, the light is very nice and soft depending on the power of the flash fired and it is spread evenly.
If your speedlight has zoom feature, a small softbox can be very useful.
Answer: You need to know your flash. I'm making a generic answer to be usefull in all fhash models and brands.
1) The hotspot

Grab a sheet of paper, with some grid on it, for example draw some lines every 5 inches. Hold it on a wall.

Put the flash pointing at the paper, lets say 10 inches away. Use a tripod or stand if you have one.

Put the flash zoom at the lower focal length, lets say 28mm. and shoot it to the paper.

Take a picture and measure the hotspot. It will cast a rectangular hotspot.

You can repeat for example now 20 inches away, then 30 to confirm your findings.

Now you have an idea of the softbox size you could have. Not only the box size, but also the internal distance to the flash needed.
Normally a speedlight shoots a rectangular beam (more eliptical), not a square one (or round).
2) The power

Shoot the flash at a white wall, acoeding to some estimates you made at the previous point. For example with the flash 2-3 feet away from the wall.

Use this bounced light to iluminate a test subject. A standing person.

Do not use full flash. Use 1/2 or 1/4 and experiment with ISO 100-200 probably 400.

Depending on the results now you have an idea of the power of the flash.

There are diferent kind of softboxes.

Some shoot the light directly to the white silk, some shoot it to a "pre difusser", and others bounce the flash to the silver interior.

A pre difusser and a bounced softbox help to even the light, but also lowers the total output, probably 1 stop.

Some softboxes allow to put a head holding not one but 2-4 speedlights.

Some softboxes allow more freedom changing the tilt angle than others.

Go for a softbox designed for a speedlight. But the point is that you now have some more information to make a decision.
A quick test I did
With a 560III passing thru a big "photopgraphic" silk:

At 30 inches from the silk

Cast a hotspot aprox 35 x 30 inches

Gives an f/8 at 1/2 power at 40 inches away.

But at the end
Buy the biggest softbox for speedlights you can find. a 80x80 octobox with an internal difusser will cast a nice light on a subject. You always can play with the iso or aperture. :o)
Comment: The softbox will cut three stops of light so the speedlite will struggle. Usually in studio you shoot at 100ASA but you could bump this up to 400, 800, 1600. So perhaps you can pull this off but you won't have the convenience of a studio light.


Is there a way to download the default Minecraft 1.17 textures?

Question: I want to make a Minecraft texture pack in 1.17 by editing the default Minecraft 1.17 textures but I don't have Minecraft. I can't download Minecraft because I am 12 and don't have money to pay for it so I searched it on Google and only found alternatives. Is there any way to download the default Minecraft 1.17 textures?
Comment: I don't think an attempt to create a texture pack without access to the game itself makes much sense. You're bound to make mistakes - everyone makes them, always, nothing like this ever works at the first try. You need the game to test your texture pack, spot and fix your mistakes.
Comment: If you still have the Mojang account, just log into minecraft.net and download the game. You still own it and you can install and play it anywhere you like, you're only not allowed to log in with the same account from multiple computers simultaneously.
Comment: If you want 1.16 textures, you could always find the textures as images [here](https://www.minecraft.net/en-us/addons) and scroll to the bottom ([or just click here](https://aka.ms/resourcepacktemplate)) and find the bedrock ones, but they are named differently and some stuff is missing and some stuff is there that isn't in Java, otherwise I'm not sure if you can (legally, I'm sure you could easily find some pirated ones somewhere)
Comment: I don't have a Mojang account.
Comment: The download you posted is for 1.16. Is there any similar download for 1.17?
Answer: You can extract the minecraft textures from the minecraft JAR file, you should be able to find the latest 1.17 snapshot JAR file downloads on the Minecraft Wiki.
You can then use an archive utility (like 7-zip) to extract the JAR and edit the textures (which are located in the assets/minecraft/textures folder), then just copy the folder to the place you want to make your texture pack.
Comment: Where is the JAR file on the Minecraft Wiki?
Comment: @SebastianHerb just install the game and go into the assets for the version
Comment: I can't install it but i found another source.
Answer: You can download the Default texture pack 1.17 and older versions from https://texture-packs.com/resourcepack/default-pack/


How one can find a string whose MD5 hash has a specific prefix?

Question: I've heard that there is a string that contains only the letters a to z whose MD5 hash begins with the hexadecimal prefix 314159265358 and the rest can be arbitrary. How can one find such a string and how long would the search take on a normal laptop?
Answer: The only way to find a hash with a specific value (disregarding preimage attacks, which MD5 is still secure against) is to hash values until you find one that matches. 314159265358 is 12 hexadecimal characters, which is 48 bits. You would expect to find a specific 48 bit prefix after 247 guesses with probability 50%, so the question becomes how fast can you do 247 hashes on "a normal laptop"?
My laptop is getting pretty old now (2013 I think) but I ran hashcat on it in benchmark mode to see how well it could do. The GPU (GT 730M) was able to do 535.6 MH/s, so I would expect 247 hashes to take around 73 hours. A GTX 1080 appears to achieve around 25 GH/s, so that would only take around an hour and a half. Of course, that's only for a 50% chance; it could take more or less time than that, but it's a decent estimate.
That the hashed string contains only a-z is mostly irrelevant, as hash functions take arbitrary input and deterministically output a fixed number of bits. Since the input is restricted to fewer characters you may end up with a larger string to hash, which could cause the hash to be slower as it's hashing more data. MD5 appears to operate on a 512 bit block, but due to its padding you can only hash 447 bits before it uses 2 blocks (which would presumably cause it to take approximately twice as long, but I haven't tested). 447 bits rounds down to 440/8 = 55 bytes, so you can hash 55 characters before losing performance. 55 characters with 26 possible values is 2655; log2(2655) ~= 258, which is significantly larger than the 128 bit output size, hence I would expect that almost every possible MD5 output could be generated by hashing a string of [a-z]{1,55}.
Answer: There is an infinite amount of strings that will have an MD5 result starting with whatever fixed string you like, for the simple reason that the input space of MD5 is infinite while the output one is finite and limited to 128 bits.
You can of course not find them with one operation, you have basically to test them all an stop when you are happy.
So in your case you start with a, compute MD5, try with your criteria, stop here or go to next case b... until z, then aa until az, ba until bz and then until zz, then aaa, etc.
Then you can apply various optimizations, including using lists of precomputed hashes that you can find online. Have a look at "Rainbow Tables", for example here: http://project-rainbowcrack.com/table.htm
Some may offer you "reverse search", but of course that can not be exhaustive.
As for the time it may take, as we say in French: "it depends".
There is absolutely no way to give you true precise definite numbers for this kind of performance question, it depends too much on the hardware.
By the way, what is a "normal" laptop?


Does a Wizard need a spellbook to cast spells, or just to prepare them?

Question: I had recently gotten into an argument with a fellow player on the subject of how spellbooks work. Specifically, does a Wizard require access to his book in order to cast spells, or just to prepare them? In context we were facing against an enemy party that included a wizard, and the player mentioned suggested trying to shoot the Wizard's spellbook using his bow in order to sunder it and, he assumed, disable all her prepared spells. I and some other players contested that and in the end he decided to just shoot her in the head instead, but just to double check: would that have worked or not?
Answer: Just For Preparation
The short version is: you're right. Wizards need a spellbook to prepare spells (from the book), but not to cast. The book is not a component/material/focus/requirement of casting the spell.
Long version:
The preparing spells rules are here, and to prepare from a spellbook you need the book. That part is pretty straightforward.  Here's an important part:

Until she prepares spells from her spellbook, the only spells a wizard
  has available to cast are the ones that she already had prepared from
  the previous day and has not yet used.

The casting rules are here, including what you need. Here's one useful note:

First you must choose which spell to cast. If you're a cleric, druid,
  experienced paladin, experienced ranger, or wizard, you select from
  among spells prepared earlier in the day and not yet cast

You'll note that in all the rules for casting a spell, the word "book" never appears. Wizards can cast anything they have prepared, provided they have the requirements listed in the spell. Those include things like material components, focus, the ability to speak or do somatic gestures, and anything else that a spell might list. Spellbooks are never listed for the Wizard class.
Comment: "Until she prepares spells from her spellbook, the only spells a wizard has available to cast are the ones that she already had prepared from the previous day and has not yet used." And cantrips, which don't require preparation and can still be cast without a spell book.
Comment: @RobertF Got a source for that? I see nothing that states cantrips are special in the rules.
Comment: My copy of the D&D Basic Rules states on p. 30: "Spellbook: At 1st level you have a spellbook containing six 1st-level wizard spells of your choice." More nonzero (= non-cantrip) spells are added to the spellbook as the wizard levels up. On p. 78: "A cantrip is a spell that can be cast at will, without using a spell slot and without being prepared in advance." Since preparing wizard spells requires studying spells from the spellbook, and cantrips are not included in a wizard's spellbook, it stands to reason that cantrips can be cats without a spellbook. At least that's how I read the rules.
Comment: @RobertF That must be a basic thing. The 3.5 rules don't say that, they say this: "A wizard begins play with a spellbook containing all 0-level wizard spells (except those from her prohibited school or schools, if any; see School Specialization, below) plus three 1st-level spells of your choice. For each point of Intelligence bonus the wizard has, the spellbook holds one additional 1st-level spell of your choice." There's also a column for how many 0 level slots you have. Pathfinder changed it as well.
Answer: Spellbook to prepare is correct. Imagine the spellbook like a cookbook. You know what the recipe is, but you can't really remember every single detail, so before cooking, you look over the recipe book, and refresh your memory, then you cook your dish.
The Spell Mastery feat will allow a certain number of spells to no longer need their spellbook to prepare that particular spell. Imagine that same chef, who doesn't need to look at his cookbook anymore for a particular dish. He has cooked it so many times he can recall it from memory. Now he will stop to think every now and then, but it is so deeply engrained in his memory, he doesn't need to consult his cookbook anymore.


How can I replace Finder with Path Finder in OS X Lion?

Question: I downloaded Path Finder and like it a lot, but Finder still takes over some functionality that I'd prefer Path Finder to do. For instance, if I open a folder on my desktop it opens in Finder, and when I mount disk images, they open in Finder. Is there a way (short of going in low-level and replacing Finder stuff with Path Finder stuff, which I don't really want to do) to make Path Finder do everything that Finder does by default?
Answer: According to the Path Finder Support Forums, it is not possible to completely replace Finder with Path Finder. For more information see "Can I replace OS X's Finder with Path Finder?"
Answer: These days (2016) Path Finder is much better integrated already from the start.
Often not having Finder running is a good prerequisite for having Path Finder take its place, but this is not always necessary. You can make Finder quit when Path Finder starts in the preferences (See the Finder tab) and you can quit Finder from there as well.
Quit Finder
A convenient way to quit Finder is also adding a quit command to its Archive menu by typing this into Terminal defaults write com.apple.Finder QuitMenuItem 1, then press return.
The following two techniques should make Path Finder take the view calls from third party applications, but "Show in Finder" when selected from the Dock will probably not work.
Setup Path Finder to intercept Finder calls

Control-Click (Right-Click) on Path Finder and select "Show Package Contents." Go inside the sub-folder "Contents"
Double click on the document named "PkgInfo" and replace the "APPLPFdR" with "FNDRMACS"
Save and close the document.
Log out and in again

Make Path Finder default file viewer

Go into terminal and type defaults write -g NSFileViewer -string com.cocoatech.PathFinder and press return. If this is not preferred later or isn't working you can undo with defaults delete -g NSFileViewer and return.
Reboot


MongoDB as a log storage. Choosing shard key

Question: I'm designing a log storage system based on MongoDB.
I want to shard a log collection to increase ingestion and capacity (distribute writes to several machines) while allow fast search.
I should be able to increase ingestion by adding more nodes to the cluster.
My collection has following fields:
Subsystem - string, name of the application. E.g: "SystemA", "SystemB". ~ 100 unique values.
Tenant - string, the name of the deployment. It's used to separate logs from different application deployments / environments. E.g: "South TEST", "North DEV", "South PROD", "North PROD". ~ 20 unique values.
Date - timestamp.
User - string.
SessionId - guid, logically groups several related log records.
Data - BLOB, contains zipped data. Average size = 2Kb, maximum = 8Mb.
Context - array of key/value pairs. Both key and value are strings. It's used to store additional metadata associated with event.
The search could be performed by any combination of fields Subsystem, Date, User and Context.
Tenant almost always will be specified.
The question is - what shard key and sharding strategy will be better in that case?
My suggestions:
The simplest case is to shard by Tenant, but it will cause highly uneven data distribution, because PROD environments generates much more logs than DEV.
"Tenant + Subsystem" seems to be better but still there are subsystems that generates much more logs than other subsystems.
And also subsystem is not mandatory - user can omit subsystem during search and search query will be broadcasted.
"SessionId" will cause even data distribution but search requests will be broadcasted to all nodes.
Comment: On what criteria will you search for the data? E.g., what will your most common queries going to be? Could you list the common queries and find a pattern within them?
Answer: For even write distribution, the SessionId looks like a much better idea (Or a hashed index on other fileds). Proper indexing should solve queries then.
The other two options have very low cardinality (and therefore very large chunks).


Algorithm Design challenges

Question: In my course we discuss algorithms (greedy, dp, div & conquer, etc.) and efficiency. Do you have any experience with assignments that consider also time of execution as a criterion for grading? Do you use any tools for measuring execution time?
Answer: Execution time is unreliable due to variations in hardware and, especially, operating systems. Paging and multi-level cache can make such things worthless. That is why theoretical measures are used.
The actual execution time depends on the specific implementation of the algorithm, not its structure. Implemented poorly in Java it will run slower than if implemented well in C (and conversely). Paged operating systems, such as Unix and its variants (and others) put an extra load on algorithms at scale. Multi level cache can speed things up but vary between processors.
Efficiency of an algorithm is a theoretical concept and so is measured theoretically, perhaps by counting comparisons. This might mean something if you compare two algorithms on the same hardware, but may even be misleading if the implementation causes, for example, page thrashing.
In addition, most modern OSs are multiprogrammed and a given program has little control over whether it has complete control over the processor while it executes, or even over a single thread.
But most operating systems will have a way to give you the actual running time of the execution of a program. A few thousand executions will give you an accurate picture for that algorithm on that set of inputs, but might vary widely if you double the inputs.
See the Linux date command for example. You can integrate it into a shell script that executes a program a few thousand times and get some averages.
Comment: For complete programs, not algorithms, a crude measure such as the difference between two unix times (in seconds) is probably enough. But algorithms are intended to be rather dense instruction sequences.
Comment: you are making valid and good points. I was wondering, how do they compare timing in competitive programming then?
Comment: @DrimadesBoy, I served as judge on ICPC once. Programming contests force to code one algorithm for a problem. As far as they allow several languages, each problem has a different timeout (rather generously assigned) for each language (to weed out brute-force style solutions and infinite loops).To me they look based on rough speed comparisons bewteen languages (e.g C/C++ 10 times faster than Java). There are several on-line judges around, check their time allowments for problems,
Answer: To build on what @Buffy said, one way you could go about it in a language like Java is to make them use your own custom data-wrapping objects.  If the algorithm takes ints, pass in Ents instead.  If your algorithm takes doubles, use Dobles -- the name doesn't matter.
The reason to do this is that you can implement Comparable and override equals(...) in order to keep track of accurate counts of all comparisons with static variables.  Then you can use reasonable ranges to figure out the run-time of the operation, regardless of the system clock, threading, or the hilarious cat videos running on your computer while you are grading labs.
You'd have to explain to the students what you are doing, and mention that extracting the data and simply using it directly for the comparisons would be considered a cheat, and that anyone engaging in such actions would have automatic zeros on the assignment.
If I took this route, I would also provide direct sample code that simply demonstrates how to mimic ==, <, <=, >, and >= functionality with the provided data types.  I would not consider figuring out how to use my wrappers something that the students should need to do.  The wrappers would be in place purely for the purposes of accurate grading.  They shouldn't, themselves, be part of the puzzle of the assignment.

Algorithm Design challenges


What's used more to submit a search, enter or submit button?

Question: There must be data out there about this. Do more people just hit enter after their search term or do they hit the "Search/Submit" button?
Comment: Possible duplicate [here](http://ux.stackexchange.com/questions/8876/usability-of-hiding-the-submit-button-and-using-the-enter-key-to-submit).
Comment: @Anderson I don't think it's a duplicate, but it's certainly related.
Comment: Here's an [another closely related question](http://ux.stackexchange.com/questions/126/do-you-need-a-search-button-with-a-search-box).
Answer: I'm not aware of any statistics, but I think Luke Wroblewski would point to the need for "a clear path to completion", which an explicit button provides. A submit button in a form (even a simple search form with a single input) does more than just provide a control for someone to press - it marks the end of the form, clarifies the purpose of the form (assuming the wording of the button is more descriptive than "submit") and serves as a call-to-action to submit, even if the user then decides to perform that action using their keyboard.
Comment: LukeW's "clear path to completion" definitely plays into this, I'd add that giving them a call to action allows the user to finish the form in his or her own way. I'm an "enter/return" guy, but I know plenty of people (less-than-tech-savvy) that will ALWAYS click an action and don't understand that enter does the same thing.
Answer: This is a fun question, and we ought to be able to answer it without disclosing proprietary information.
Here are some sketchy observations, though I hope others with access to their own analytics data can compare, critique, and share. I'm not confident in the reasoning here. Perhaps this will get us thinking.
After a glance at our search stats (from covenanteyes.com) over the past month, I see an indication that using the enter key is a more frequent action than clicking the button itself. Based on the 2884 searches I'm looking at, it seems that 752 were triggered by a click of a search button and 2132 were triggered by the enter key. So, about 26% used a button and 74% used the enter key.
What leads me to think I see this data? The search form in the top-right corner of our web page has the submit button as an image. As it is named "sa," I can track that in the query string of the search results page. As an INPUT element with a type of IMAGE, the form submits the coordinates of the actual click. So when I click the button, I see something like this in the query string: sa.x=7&sa.y=9. The x and y values vary based on where on the image the person clicked. When I hit the enter key, I see sa.x=0&sa.y=0.
It is possible, though I believe rare, that a person will click the very top left pixel of the button and also get x=0&y=0, but it is so unlikely that I've ignored it. People tend to click somewhere in the middle of the target.
Here is why I seriously question this data. We had 4194 total unique searches, but the URL patterns aren't consistent: they don't all have the sa.x and sa.y parameters. I only evaluated the 2884 that contained the x and y values. Now, when I simply tried the searches to see what happened to the URLs, the x and y values did in fact appear. They always will when those forms are used, because that's how form submissions work.
But still, pretty big assumptions here. Are there other times when they will appear which can also cause the zero values? That would throw off the proportions, perhaps in a large way. Anyone want to grab the baton and run the next leg of reasoning this through?
What usage patterns have I not realized? Why are those parameters missing in the other searches?
Can someone else look at their own search data and report back?
(Aside: no doubt Google's live search dramatically changes this, as every keystroke seems to refresh the search results. I'll bet button use in that context plummets.)
Answer: Both.
I mean, any one.
Usually the search box has an attached button with a magnifying glass.
But, as the user most of the times has her hands in the keyboard (not in the mouse), the search artifact also honors the enter key when the focus in in the search box.
Some users will not dare keying enter and would go for the safe button click.
So offering both options is customary.
Comment: Do you have any data to support that claim? I mean, it feels logical, cut Ryan was asking for data on which is used more, not for opinions or gut feelings.
Comment: Hi @Andre, this is not *gut feeling* or *opinion*, it is yes a *used more* thing.
Like, setting the vertical scrollbar at the right of the window. It is going to be very difficult to find a test about "where do you place the vertical scroll bar" because it's such an established idiom that everybody takes it for granted.
Comment: This, the magnifying glass plus enter idiom, seems to be established after many years of search artifacts design.
There is a lot of information in Alertboxes published along the years: http://www.useit.com/search/serp.html?q=search+box we all have read along the years and built knowledge.
Comment: Hi Juan: The actual _question_ was which of the two are _used_ more. Not which of the two should _be_ there. One could simply measure that in the real world, right? So, there would be data for such cases. Your answer that both are used equally is, without further backup, conjecture.
Comment: note the SE doesn't have a submit button no it's search and requires the enter key
Comment: Oops! You are right, I didn't read your question very carefully.
@ratchetfreak true, maybe because this is a special audience of guaranteed computer-savvy users.
Answer: Sorry, this isn't a direct answer! But you could measure this quite easily. Add a bit of javascript to amend a hidden form field. If people click the button set a hidden form field one way, if they click set it another. (If it's not set either way, they didn't have JS enabled!).
It would be interesting, especially to measure it against other things such as demographics. I suspect the results would be well correlated with demographics, which might mean you could make a reasonable guess if you knew your audience.
@BryanRobinson's comment on @MattObee's answer matches my experience having worked on designing systems for older people with little (or no) computer experience that novice users click, experienced users hit enter, hence my expectation that demographics will have a large impact.
As an aside, StackExchange's design without a button, just a field could be taken as a (probably quite accurate for this community) expectation that SE users are experienced users. It may be a bit less accurate for som other SE communities though, such as english.stackexchange.com.


Can't group by a column (Business Area) in my document library

Question: Business Area is a required column in my doc library. It's set up as "Checkboxes (allow multiple selections)". I have created several views, and in some of them I want the option to group by that column. However, it is not an option. Here's the reason I need that: In each view I am using the filter "Show items only when the following is true" for this column - but rather than using "is equal to" I need to use "contains" due to the multiple selections. That's fine, except that two of the Business Areas are Sales and Sales Associates. If I make it "contains Sales" it will bring up docs related to both, so I need to be able to group the display by Business Area to keep them separate. Can you tell me if there's a way to do what I need to do? Thanks!
Answer: I would make a separate view for each Business Area that is grouped by Sales Associates.
Comment: The problem with group by is that you are only able to have an item listed once in the same view.  So the multi-select choice column will not work.  The views are the way to deal with that.  Then make a link list of the views, or add them to the quick launch.
Comment: Thanks, I will try that. I appreciate the quick response.
Comment: I'm still having trouble with this one. I already have a separate view for each Business Area, but it seems only certain columns are available in the "group by" list. Does it have anything to do with the fact that this is a different document library from the default Shared Documents? (i.e., it is one I created)
Comment: That sounds right. I will work on that. Thanks for your help, Jammin4CO!