Is there an easy way to align two objects on a specific axis?

Question: Other than manually typing in locations, is there an easy way to align objects on an axis like you would in Visio?
Answer: You can use Align Objects available in the 3d view header under Object > Transform > Align Objects.

This will bring up a panel in the toolshelf and you can choose the axis to align the selected objects on. You can also choose to align relative to and the mode to align by.
Comment: shift + click x/y/z to align by multiple axes.
Answer: I like to use the Pivot Point Align feature in conjunction with zero-scaling.

Press Alt, (comma) to activate Pivot Point Align, or click the button next to the pivot center selector in the 3D View header.
Select your two objects.
Press S to activate scaling. Then, press the axis key (X, Y, or Z) corresponding to the axis on which you want the objects to be aligned.
Press the 0 (zero) key on your keyboard. This will scale the distance between the center points of the objects to zero (i.e., they will be on top of each other) but since Pivot Point Align is on, the scale of the objects is conserved.

I really like this method for a few reasons:

It's quick: it only takes me about five seconds to do RMBRMBAlt,SX0Enter.
It works in edit mode as well, to align vertices.
You can easily specify where they should be aligned to with the normal pivot point settings. For example, by default, they will align at the median, but you could also choose to do the 3D cursor, active object, etc.
You can select a local axis along which to transform. To do this, select the relevant object last (so it is the active object), and then press the axis key twice. For example, to align a cube and sphere on the sphere's local X axis, select the cube, then the sphere, then press SXX0. You can also do this with gimbal, normal, or view axes by selecting the appropriate axis type from the Transform Orientation dropdown menu.
You can use proportional editing to gradually scale nearby objects in as well.
Essentially, you can use all the editing features you normally use.
Comment: I suggest to add this step to your main post because this makes it work: "(2) set your pivot center (. dot) to "Active Element""
Comment: Unfortunately this method used as you just described moves both objects one toward the other to the median point of their distance. This means that it doesn't properly work if one obj is already where in the right position. To solve this inconvenient: before execute your procedure, just select the obj you need to stay in position then go to property panel > Transform > Position and click on the lock of the 3 axis to lock the object movements. Do the same on the rotation and scale lock accordingly on your needs. Then execute your procedure. Enjoy.
Comment: @willywonka: A beauty of this method is that it *doesn't* require such a complication. Instead, do either of these: (a) (1) make the object already in the correct position your active object, (2) set your pivot center (`.` dot) to "Active Element", (3) execute my procedure; or (b) (1) put the 3D cursor at the correct position (probably using `Shift-S U`), (2) set your pivot point center (`.` dot) to 3D Cursor, (3) execute my procedure. This is what I mean by "You can easily specify where they should be aligned to with the normal pivot point settings"!
Comment: @willywonka: This is in the main post: it's the third bullet point of the second list, as something that you can do _optionally_. (It's not something that you always want, so it's not in the main mechanics list.)
Comment: Oh... I see... I didn't notice because it is not much explicit as it is in the comment: "set your pivot center (. dot) to "Active Element"" seems to me more clear than "You can easily specify where they should be aligned to with the normal pivot point settings. For example, by default, they will align at the median, but you could also choose to do the 3D cursor, active object, etc.".... Perhaps IMHO it could be an idea to evaluate to add an explicit indication of that to first bullet list as first or second item with the indication that it is optional. IMO it could improve the answer clarity
Comment: Strictly speaking Alt+, just means..'in object mode, manipulate pivot points, taking everything else in their objects with them'.  Then you can do anything you like, not just align.
Answer: You can do this with Mesh Align Plus (my addon). After installing the addon, either watch the steps in the GIF or read the text version below:

The feature you're looking for is the Quick Align Lines operator in the 3D View > Tools Panel (T) > Mesh Align Plus Tab, in its own panel.
1. Pick a destination target (stationary edge that you're aligning to)

In edit mode (Tab), shift + right click to select the two edge verts you want to align your object with
Hit Grab Destination

2. Pick a source target (edge that will be aligned with the destination)

In edit mode (Tab), shift + right click to select the two edge verts that need to line up with the destination when the alignment is applied. Leave them selected.

3. Apply the operation

Make sure the object you want to move is selected, and (in object mode or edit mode) hit Apply to: Object
Answer: You can mark the spot with your cursor and, select your object and hit Shift + S then select
Selection to Cursor. This will snap your selected object to wherever your cursor is.
Answer: You can use Snapping with the rotation snapping option enabled:


Can propeller driven aircraft sustain speeds at or above Mach 1?

Question: Has any propeller driven aircraft ever achieved and sustained supersonic speed? If not, why can't propeller airplanes achieve that speed?
Comment: In controlled horizontal flight?
Comment: @mjs yes.in a steady controlled horizontal flight
Answer: Supersonic level flight?  No.
The fastest propeller-driven aircraft is either the turboprop-powered TU-114 with a measured top speed of Mach 0.73 or the turboprop-powered XF-84H "Thunderscreech" with a design top speed of Mach 0.9 and an actual top speed of either Mach 0.83 or Mach 0.7 (sources disagree).  The latter is an indication of why supersonic propeller-driven aircraft are unlikely: the continuous sonic boom coming off the propeller tips made the Thunderscreech the loudest airplane in the world.
The record for piston-engine aircraft is slightly lower, at Mach 0.71.
Comment: @falstro: The sonic boom is not only occurring at Mach 1, but at all speeds above it. When a body travels faster than the sound, the forward-moving sound waves are compressed and will form a cone. When this cone moves over the ear of an observer, he will hear the pressure changes across the boundary of this cone as a sonic boom. Theoretically, a properly designed propeller will still work at supersonic speeds, but the efficiency will be so horrible that nobody has tried that seriously.
Comment: @falstro more of a boom? The Thuderscreech never went above mach as a whole system. The propeller turned such that the tips were above mach. As soon as they did so they were radiating a sonic boom. Each blade was. When a blade passed the plane (level/altitude/height of your ears) of your hearing you would hear it's boom, then when the next blade's boom came across your ears, you would hear it's boom. Many booms per second, which to you would "sound like" one long continuous boom, but in fact were waves of booms radiating out.
Comment: @falstro - If you read the wikipedia article you'll see that the XF-84H's propellor tips were going supersonic even when it was on the ground.  Causing aaaallll sorts of havoc for ground operations.  The inability to get to a designated "supersonic" zone before unleashing a huge sonic boom seems like quite the show stopper.  Further, the sonic waves coming from the tips (when the rest of the craft was subsonic) appeared to mess with the aircrafts general stability.  I'd think those two reasons together are sufficient to explain that sentence.
Comment: @falstro: I would think that a larger crosssection (due to the propeller) would make for a louder boom.
Comment: Why would there be a continuous sonic boom coming off the propeller tips? If it was turning fast enough with the tips supersonic and the hub subsonic I'd agree (some part of the prop would always be precisely at Mach 1) but in this case the entire prop would be supersonic wouldn't it?
Comment: @PeterKämpf you are correct of course. The question still remains though, if the entire aircraft is supersonic, why would a spinning prop make more of a boom?
Comment: Compare my comment about the 'radiation of booms' to what happens when an entire aircraft passes through mach. One boom. As long as it was only the blades achieving supersonic speed, they would continue to radiate the boom.
Comment: @CGCampbell oh I'm not questioning that, I'm wondering why the speed of the tips matter when the entire aircraft is supersonic. The Thunderscreech never was, sure, but the answer says `the latter is an indication of why supersonic propeller-driven aircraft are unlikely: the continuous sonic boom coming off the propeller tips`, would the fact that the there's a spinning prop make it noisier than a jet?
Answer: According to Wikipedia:
"The tip of the propeller on many early aircraft may reach supersonic speeds, producing a noticeable buzz that differentiates such aircraft. This is particularly noticeable on the Stearman, and noticeable on the North American T-6 Texan when it enters a sharp-breaking turn. This is undesirable, as the transonic air movement creates disruptive shock waves and turbulence. It is due to these effects that propellers are known to suffer from dramatically decreased performance as they approach the speed of sound. It is easy to demonstrate that the power needed to improve performance is so great that the weight of the required engine grows faster than the power output of the propeller can compensate. This problem was one that led to early research into jet engines..."
So basically the performance drops so badly that you better switch to jet engines. In fact when designing the blades, a max tip Mach of ~.9 is a hard limit of design. The text continues to say that nevertheless some propeller aircrafts were able to approach speed of sound in a dive.
http://en.m.wikipedia.org/wiki/Sound_barrier
Comment: What if you had a jet that pushed the plane above Mach 1 and then turned on the propellers? Impractical, I know, but just for the sake of the argument?
Answer: No propeller-driven aircraft has ever exceeded Mach 1. The Brits did high-Mach dive tests in Spits out to high Mach numbers but never to Mach 1. In the US, Herb Fisher did high-Mach dive testing in a modified P47 and never reached Mach 1.
The problem is propeller over-speed and high drag rise on the propeller disk.
It simply can't be done.


Converting SLD to Esri layer or lyr file

Question: Is there a software/extension to convert an SLD to Esri. lyr format, or to import the SLD directly?
Answer: If SLD is declared you can get layer parameters with parsing XML.
In ArcGIS you need add a local feature class and load it as feature layer. Next, identifying type of symbology of your layer in SLD  and next generate symbols with appropriate type in ArcGIS. Finally save your symbology to LYR.
I don't know if this script is dev... I find lot of subject for convert LYR to SLD but no reverse.
You can do a script for this conversion with arcpy and xml packages in Python environment if you want. I think lot of persons are interested in.


Is the concept of Aporia the same as the Zen concept of A Beginners Mind?

Question: Is the concept of Aporia the same as the zen concept of A Beginners Mind, or related to it, or a completely different concept?
Comment: Hi, welcome to Philosophy SE. We discourage one-line questions because they leave unclear what exactly is asked about, and it is hard to give good answers to them. Please explain what "aporia" (paradox?) and "beginner's mind" ([*shoshin*](https://en.wikipedia.org/wiki/Shoshin)?) mean to you, and what motivated the question. Do you ask whether beginner's path to zen starts from confronting a paradox (*koan*)?
Comment: Why do you spend so much time asking people questions about things they don't know about? That's why they have asked the question. It's an extremely bad practice. Because not knowing about the issues they are then prodded to invent answers from the standpoint of ignorance. Which puts the whole matter on a bad footing.
Comment: @JosephLutz To address a comment to another user you have to put @ username into it. We ask clarifying questions to figure out what people are interested in more specifically. Single sentence questions often lead to answers that have little to do with what was meant to ask, people overestimate how much words they type actually convey. And no one is wholly ignorant of what they are asking about, or they wouldn't be asking. The practice of leading questions goes back to Socrates, if not earlier. Being prodded to give answers, however flawed, is a step from ignorance to getting better answers.
Answer: Welcome, Sam Wheel.
In philosophy aporia retains, at least standardly, its Aristotelian sense. This has no commonality with zen so far as I can see if by 'beginner's mind' we mean what Suzuki does:

So the most difficult thing is always to keep your beginner's mind... Even though
     you read much Zen literature, you must read each sentence with a fresh mind. You
     should not say, "I know what Zen is," or "I have attained enlightenment." This is
     also the real secret of the arts: always be a beginner. Be very very careful about this
     point. If you start to practice [Zen], you will begin to appreciate your beginner's
     mind. It is the secret of Zen practice.  (Suzuki, S. (1973). Zen mind, beginner's mind, New York: Weatherhill: http://www.cuke.com/bibliography/ZMBM/prologue.html.)

See now what Aristotle says about aporia and the contrast will be appparent.
Aporia and Aristotle
Here is a useful account by Gareth Matthews of how the notion occurs in Aristotle:

Often Aristotle, when he begins the discussion of a
   new subject matter, first identifies the aporiai (perplexities, difficulties, antinomies or just problems) that belong to that subject and the
   sets as a constraint on his own inquiry the resolution (euporia) of
   each of the perplexing problems he has identified.
   ...

We must, with a view to the science which we are seeking, first recount the subjects
     that should be discussed. These include both the other opinions that some have
     held on certain points ... For those who wish to get clear of the difficulties it is
     advantageous to state the difficulties well; for the subsequent free play of thought
     implies the solution of the previous difficulties, and it is not possible to untie
     a knot which one does not know. But the difficulty [perplexity, aporia] in our
     thinking points to a knot in the thing [peri tou pragmatou]; for in so far as our
     thought is in perplexity [aporia], it is like those who are tied up; in both cases it is
     impossible to go forward. Therefore one should have surveyed all the difficulties
     beforehand, both for the reasons we have stated and because people who inquire
     without first stating the difficulties are like those who do not know where they
     have to go; besides, we do not otherwise know even whether we have found what
     we are looking for; the end is not clear to such a person, while to one who has first
     discussed the difficulties it is clear ...
The first problem [perplexity, aporia prote] concerns ... (Aristotle, Metaphysics, IIIB.995a24-b4, J. Barnes, The Complete Works of Aristotle, Princeton: Princeton University Press, II, 1984 : 1572-3)

The philosophical methodology this passage suggests goes something like this. Suppose one wants to know what it is for something to be a place, or a location (topos). One begins by collecting some
   of the relevant things people say about places, things that might help
   us determine what a place is. One of the things people say, it seems,
   is that the place of a thing contains it, but is not part of it, since the
   thing can leave its place without growing smaller.
   Then we collect the puzzles (aporiai) about place. For example,
   there is a puzzle about whether a place is itself in a place. If every-
   thing in the physical world had a place, then, it seems, a place must
   have one, too. But then there would be an infinite regress of places,
   which is absurd.
Now the point of the inquiry is to see if we can somehow respect
   most of what people are preanalytically inclined to say about places
  and, at the same time, resolve the relevant aporai. Suppose some-
   one then says, how can you inquire into what a place is? Either you
   know already, and so the inquiry is phony, or else you don't know,
   and so you won't be able to recognize a satisfactory answer. Aristotle replies, first, that what people are inclined to say about places
   provides some general parameters for a satisfactory account. As for
   being able to recognize what we are looking for, should we find it,
   that consists mainly in being able to tell whether the puzzles that
   our object of inquiry gives rise to have been solved in a way that
   respects what people are inclined to say. (Gareth B. Matthews, 'Perplexity in Plato, Aristotle, and Tarski', Philosophical Studies: An International Journal for Philosophy in the Analytic
  Tradition, Vol. 85, No. 2/3, Papers Presented at the American Philosophical Association
  Pacific Division Meeting 1996 (Mar., 1997), pp. 213-228: 225; Aristotle, Physics.IV.)

Platonic prefiguration
Plato had been here before, of course.

Plato has Meno introduce the
   puzzle about how there can be such a thing as inquiry, for example,
   trying to find out what virtue is. Either one knows already, and there
   can, for that reason, be no real inquiry. Or one doesn't know, and so
   won't even know what to look for (80d-e). (Matthews: 223.)

While there are many examples of aporiai in the Platonic dialogues, particularly in the earlier, Plato shows little interest in the notion of aporia as such. In Meno, for example, he is more interested in the question, 'What is virtue*, than in the paradox of inquiry just cited from 80d-e.
A sharp difference from Aristotle, as any reader of the Republic will know, is that Plato sees no need to respect 'what people are preanalytically inclined to say'.
Answer: Not on the face of it. Aporia means, in the clearest form, that two common citizen's opinions, commonly held by the general population, are in contradiction or in some way conflicting. A political difficulty. This leads to the need to think them through and thus to prima philosophia, ergo: political philosophy. More in the manner of an inner teaching it means that a difficulty, an impasse, is stumbled on by an adept. So that one, Socrates being the main example, discovers a strange difficulty which turns out to be a kind of "wonder" (thaumizein). However, the implication is not that he has now become a beginner, who is always "setting out" anew, rather, he has come to an exact difficulty which exercises him (Socrates never, strictly speaking, "doesn't know what he knows," rather this is always in play with his famous "irony" and with other factors, most especially: HISTORY). Thus, the impasse itself is a gateway to the wonder or sheer bliss of knowing being. Unlike in "beginner's mind" where the presupposed difficulties themselves are "problems" only for the ones who have advanced too far and become mired in a sylabus of bigoted narrow bespoke difficulties.
Aporia is less radical from the Eastern perspective in that it presupposes being. And thus it views there to be problems that can become questions, that which makes one wrestle and lose sleep. Form the Western perspective "Beginner's mind" lacks content, and so is mere "New Age bullshit." Ergo, it is only pure experience, even denying the concept of experience, it is without reality and so "against reason."

I provide some links to primers on the subject matters involved: https://www.youtube.com/watch?v=g_F_cxM9d5Q
https://www.amazon.com/Strange-Wonder-Metaphysics-Insurrections-Critical/dp/0231146337/ref=sr_1_1?keywords=strange+wonder&qid=1571254250&sr=8-1
Answer: The two things are unconnected. A dictionary will make this clear. Beginner's mind is an attitude and approach, a recognition of our own ignorance and an opening of our mind. It has nothing to do with aporia, defined as 'an irresolvable internal contradiction or logical disjunction in a text, argument, or theory.'
Comment: Spot on. Can't see the connexion with zen. Back to Aristotle. +1.
Comment: This is a losing answer. Which supports utter thoughtlessness. Reading dictionaries, and handing oneself over to their authority, is no way to do philosophy. Truly awful.
Comment: @JosephLutz - Lol. I've tried to reply a few times but find myself lost for words. I conclude from your answer and comment that 'beginner's mind' is exactly what you do not have but desperately need, presumably because you do not know what it is, as you make clear in your answer. I feel you would greatly benefit from looking it up in a good dictionary. A more sensible person than me would not have responded.
Comment: You are mistaken and foolish.
Answer: As the other answers have indicated, aporia and beginner's mind are not equivalent concepts. However, I don't think it would be a grossly implausible stretch to make a connection, perhaps, between the pedagogical force of Plato's aporetic dialogues and the pedagogical force of the beginner's mind concept. For Socrates the worst epistemic state was thinking that one knows what one does not know, or failing to understand the limits of one's own knowledge. Thus in the aporetic dialogues, Socrates uses philosophy in a purgative dimension, purging the faulty thoughts and paving the way for better ones. One is prepared to learn only when one knows one does not know.
The connection here is the emphasis on the purgative aspect of pedagogy: not placing positive doctrines in the head, but rather emptying. I think the two approaches (Socratic and Beginner's Mind) have their differences, but there might be a story to tell here that isn't hugely implausible.


Will beans or peas grow back after being topped by a deer?

Question: A deer got at my peas and beans. The peas seem to still have some leaves and stem. The beans are missing most of their leaves. Do either plants have any chance of regrowing or should I scrap them all and replant?
Comment: A picture of the damage would making an estimate easier and more precise.
Answer: It depends a bit on how much plant material is left, but typically they will grow back.
I regularly pinch off the tops of my young pea plans and serve them in salads and the plants grow back just fine. With beans, it's usually the slugs that munch at them and they have more trouble or need to be replaced, but that's mostly because the slugs tend to eat the whole plants.
Answer: There might be a few peas that would come back, I doubt any of the beans will make it.  Were they pole or bush beans?
I would plant more peas and beans.  They grow so fast that most people grow second and third crops before the end of the season.
As for the deer, depending on the size of your land, getting a few bales of old hay to put somewhere far away from your garden really helps. They've had a taste and won't forget so you need to erect some sort of fence.  They have black mesh deer fencing that is very cheap.  You could also get a water blaster on a motion sensor.
Comment: Big dog(s) is the only solution for deer.
Comment: @blacksmith37  You are right about that!  I've got 3 but they come in at night because we also have cougars and bobcat.  That is another reason we had to put up a huge greenhouse, deer/elk/rabbits galore.


darkstat shown blocked traffic

Question: I've installed Darkstat on a Qemu VM which is connected to a bridge interface on top of main server's interface ( eth0 )
In Darkstat report I can see many hosts in the same IP range of specified VMs are transferring packets with VM while I've blocked all of them in forward chain of Iptables,
Any one familiar with this kind of issue? any advise on how can that packets bypassing the Iptables?
Answer: My bad, Darkstat is showing traffic rightfully,
The problem was because of insecure network many packets from other IPs are being forwarded to my VM and this make Darkstat to show that IPs are transferring with my VM, Darkstat is right they are transferring data to my VM but noy my IP.

darkstat shown blocked traffic


How to command autopilot to start a fixed rate descent?

Question: Is it possible to command an autopilot to start a fixed rate descent? For example to avoid weather during the cruise phase? From what I have read the autopilot would maintain constant speed and altitude until interrupted but havent found a fixed rate descent function.
Comment: The answer greatly depends on the type of autopilot used. Small cessna's and the like generally have less advanced autoflight systems than aircraft made by Airbus or Boeing.
Answer: Here is what typical autopilot controls look like

Image source: What is a "Flight Director"?
The pilot can set the required altitude, as well as the required vertical speed to get to that altitude. A cruise decent will typically use a shallower descent than an approach descent.
Answer: This answer explains that there is a flight level change mode and a vertical speed mode. The latter will hold vertical speed until a target altitude is reached.


Webmaster tools not showing clicks but Google Analytics shows traffic from search

Question: I have Google Analytics set up on a site and it is tracking traffic correctly. I set up Webmaster tools and linked the accounts. It's been running for a few days now and says it's correctly linked. However, it's not showing any clicks from search. But Google Analytics is showing that about 65% of my traffic is coming from Google. Do you know why Webmaster tools would show no clicks from search?
Answer: Check your default URL in case that's not set to the current sub-domain/protocol. It may be you're getting clicks but they're not being attributed in the Search Console.
Search Console data is also 2-3 days behind the current date. It can vary a great deal and even be delayed up to a week.
Otherwise, Search Console should actually be more accurate due to the sampling technique used by Analytics.


How does the food industry know the expiration date?

Question: I always have this question in mind whenever I see the EXP date on different products.  I wonder how they can know a chocolate bar will spoil after 1 year or 6 months, and why they have such longer shelf life time compared to homemade chocolate bars, for example.
Comment: I doubt a chocolate bar ever spoils. More likely the expiration date is a "best by" date. Most shelf-stable stuff remains edible long after the expiration date.
Comment: Something I used to hear a lot growing up was that a Best before date was actually an 'interesting from' date    -   In other words consuming before the date was when it would be 'as expected' but if you ate/drank the product after the best before date you may have a 'more interesting' experience
Answer: Just to clarify:
"Expiration dates" (or sometimes "Best if used by" dates) are the dates when a product may no longer be of high quality.  It is not a safety indicator.  It is a quality indicator, and it is just a guideline.
Companies determine expiration dates during storage studies or stability tests.  More detail can be found here.
The reason why manufactured food items often last longer than home-prepared items is that companies add ingredients to prolong shelf life.  This is simply for economic reasons.  You could add the same ingredients, but it is often not necessary because of the scale of home cooking.
Comment: Fair distinction between "will" and "may"....edited.
Comment: Industrial processes also include protective atmospheres.  These usually help with quality but can also slow actual spoilage.  Also "*will* no longer be of high quality" is too strong "*may* no longer..." would be more accurate.  The process is more that before the date specified the manufacturer expects the product to be consistent; after the date they don't care, which is why even tinned goods often have only a year; testing for longer would be too expensive for no real benefit
Answer: There are few expressions that are not interchangeable:
Best before - It's about quality not safety. After that date the food is still good for consumption but the taste and/or texture might change. It's used for example in chocolate with "creamy stuffing". After B date the inside might not be creamy.
Use by - A "final" date for a product to be eaten OR used in other dish (than it then prolong it's life if it was thermically changed). So a product can be opened (and stored in fridge) for two weekes before it's "use by" date and it will act the same as same product with same date but opened two days prior.
Expiration - date after which food (or medicine) decline in quality in a way it can be harmful to consume. (This is for EU legislation. In USA this might be interchangeable with best before).
Those dates are established by studies and by calculations. There are preservatives, that added in A quantity to B quantity product extend it XXXX life by YYY amount of time.
It's also calculated with "worst case scenario" in mind. So with the assumption that on delivery line some quality might be loss (for example you buy food from fridge and carry it to home in 20ºC/70ºF for an our home).
There is also time when content start reacting with it container. An EXP/ best before date on plastic bottle of water don't mean the water goes bad but the reaction inside might change the water taste or values (if it's mineralized for example).
Answer: I assume they are doing lot of laboratory analysis and testing and experiment whilst preparing the industrial recipes.
They will test the product a different dates to see how well it behaves,  check if there are molds, pathogens ... ie. if it is safe to eat.
Depending on what they want, they will either change the recipes to get a required expiration date ( I want my cookies to last 3 months) or change the expiration date (those cookies last 1 month)


Can anyone help me identify this coin?

Question:
This is a roman coin, I'm not sure of the date and who is on the front.
Comment: The lighting and focus kind of make it look like a stock photo or some sort of product. Did you find the image somewhere or did you take the photo yourself? Either way, do you have more images or any other information about it?
Comment: Hi, welcome to History.SE. Could you give us measurements and, if possible, show us the back face? Straight on, well lit, high resolution images will help as well.
Answer: This coin appears to be showing Constantine I, timeframe  307-337 A.D. Numerous similar coins can be seen on this search, mainly at commercial sites.
A good look from a site here

The above site lists this coin as:

DIVUS CONSTANTINE I THE GREAT (Died 337). Ae. Antioch. Struck under
Constantius II and Constans.

Another good image can be seen here
Comment: as a side note: whoever made the ring did cut the whole "left" side of the coin's inscription to conform to the smaller diameter

Can anyone help me identify this coin?


How can I delete all CiviCRM Campaigns?

Question: How can I delete all CiviCRM Campaigns without having to delete one at a time?
I have over 500 of them.
Is there a way to do this with the API explorer?
Answer: Yes, you can do that with chaining in API Explorer:

$result = civicrm_api3('Campaign', 'get', [
  'sequential' => 1,
  'options' => ['limit' => 0],
  'api.Campaign.delete' => ['id' => "\$value.id"],
]);

Answer: The API Explorer will only delete one at a time, unfortunately.
If you have command-line access, cv is a nice way to access the API to do this.  You can run a command line:
cv api Campaign.delete id=1.
Sometimes if I'm feeling lazy and I don't want to code something to mass delete, I'll do the following:

Open a spreadsheet program.
In column A, start filling in numbers: 1, 2, 3.
Select those cells and then drag.  LibreOffice Calc, Google Sheets and Excel all know that you want to continue the series.  Continue until you have however many rows you need (in your case, over 500).
In Cell B1, put the following formula:

="cv api Campaign.delete id=" & A1

Copy/paste that down all of column B.  The end result is that you'll have 500+ lines that will each delete a single campaign.
Copy Column B, then paste it into a command line terminal.
Comment: Brilliant! Worked perfectly. In my case I used drush cvapi because cv api didn't work. but I did the whole spreadsheet thing and worked amazing. Thanks!

How can I delete all CiviCRM Campaigns?


How do I feed a sourdough starter?

Question: The cookbook I'm using tells me how to make a sourdough starter, but not how to feed it after I take out what I need for the bread. What do I do with the starter once I've used some? I don't think I'll use all of it at once.
Comment: related: http://cooking.stackexchange.com/questions/931/how-can-i-bake-bread-using-a-mother-culture
Answer: When I've made and used starters in the past I've generally fed it 1/2 cup water and 1/2 cup flour every other day.  The challenge with sourdough starters is that you need to be using them regularly as the volume obviously grows if you're just feeding it and not using it regularly.  Of course a friend, family member, or neighbor might be thrilled for you to share it with them but then again...it's kind of like having a pet - you have to keep it fed!
Comment: You can always discard part and feed it to keep it alive. A waste, yes, but better than not feeding or having it outgrow the container.
Answer: I feed starter with a 50-50 mix of water and flour.  Usually 1/2 cup water 1/2 cup flour for a small container.  You can eyeball the ratio.  It isn't critical to get it perfect.
If you keep the starter in the fridge you can get away with feeding it twice a week depending on your yeast strain.  You can do this by eye…if the starter starts to look ugly when you take it out to feed, you should feed it a little more often.
One thing I will say is that you can resurrect a starter that seems long past edible.  The starter will get a cloudy fluid on top of the batter and develop a really strong smell if you let it go too long.  My personal experience is that you can pour off the watery fluid and some of the batter if need be.  Then add a good feeding of flour and water.  It will take a little longer than usual to build up again.  Yeast is a very durable critter.
Comment: Generally when I get a layer of hooch (the cloudy/greyliquid), I find that it mixes itself back in when I bring the starter into the warm and it gets up to room temperature. Even if it doesn't do that, you can just mix it back in. There is no need to pour it off. I've been following this principle with my current starter for around 7 years with no problems.
Answer: You just have to add more flour and water periodically so your yeast doesn't die. You can add more to replace. You don't have to feed the starter as often if you leave your starter in the fridge but then you have to let it warm up before you use it.
This video is awesome for showing how to make and maintain your starter.
Answer: Maintaining a Starter:
Feeding Schedule:
As a general rule:  Once your starter is healthy and active, bubbling, rising vigorously, and smelling sour, you have two options:

If you store the starter at room temperature, you need to feed it twice a day. Don't wait for the risen starter to collapse before the next feeding, because it messes with the ph levels and can make the yeast and bacteria less active. Every 12 hours, feed it.

If you store the starter in the fridge, you can go up to a week between feedings.  The cold won't kill the yeast and bacteria, it just slows them down. Just make sure the starter doesn't get shoved into a super cold spot and freeze.

The feeding process:
Stir the starter, remove all but 4 ounces of it (you can either discard the rest or use it to bake something). To the remaining 4 ounces, add 4 ounces flour and 4 ounces of purified or bottled water (chlorine in tap water is bad for the yeast and bacteria, and most filters remove chlorine taste, but not all the chlorine). Room temperature starter gets room temperature water; refrigerated starter gets lukewarm water.  Stir until no dry flour remains. Cover with a non-airtight lid.  Refrigerated starters need to stay at room temperature for several hours after feeding so the yeast and bacteria have a chance to wake up and eat.

Source

After removing some of your starter to bake bread, feed the remainder as you normally would, but perhaps with a bit more flour and water than usual if you're left with less than 4 ounces.
This can be avoided by planning ahead. The day before you want to bake, when you feed it, put the removed starter in a bowl and feed that, too.  Your primary batch of starter won't be depleted, and you'll have plenty of starter for your baking.
Answer: I don't do sourdough in warm weather, it wastes too much flour.  In the cooler months I use half the starter once a week and then add 1 cup flour and one cup water and watch the mix, when bubbles stop appearing (use a ceramic bowl with at clear glass top), will either make up another batch of bread or pour out half the starter and add the 1 cup of flour and one cup water.  This refreshing of the starter is temperature related; the warmer it is the faster the yeasts work and the more often it must be renewed.  I keep mine on the floor in a cool part of the kitchen.  If you see pink in your starter, toss it and start over.

How do I feed a sourdough starter?


Oraclize failing to return data when using example contract

Question: I am trying to use the example Oraclize contracts at https://github.com/oraclize/ethereum-examples/tree/master/solidity, including KrakenPriceTicker.sol. Here's my contract (modified very slightly):
pragma solidity ^0.4.0;
import "github.com/oraclize/ethereum-api/oraclizeAPI_0.4.sol";

contract KrakenPriceTicker is usingOraclize {

    string public ETHXBT;
    uint public timesCalled;
    uint public timesFailed;

    event newOraclizeQuery(string description);
    event newKrakenPriceTicker(string price);

    function KrakenPriceTicker() payable {
        oraclize_setProof(proofType_TLSNotary | proofStorage_IPFS);
    }

    function __callback(bytes32 myid, string result, bytes proof) {
        ETHXBT = result;
        newKrakenPriceTicker(ETHXBT);
        update();
    }

    function update() payable {
        if (oraclize_getPrice("URL") > this.balance) {
            newOraclizeQuery("Oraclize query was NOT sent, please add some ETH to cover for the query fee");
            timesFailed++;
        } else {
            newOraclizeQuery("Oraclize query was sent, standing by for the answer..");
            oraclize_query(60, "URL", "json(https://api.kraken.com/0/public/Ticker?pair=ETHXBT).result.XETHXXBT.c.0");
            timesCalled++;
        }
    }

}

When the update() function is called and some ether and gas sent with it, it should call the kraken.com api and update the value of ETHXBT with what's returned. However, the value of ETHXBT is always blank. I know the oraclize_query is being called because the timesCalled variable does increment. So there appears to be an issue with the result returned, though going directly to https://api.kraken.com/0/public/Ticker?pair=ETHXBT shows there shouldn't be any problem.
I've deployed the above contract at https://ropsten.etherscan.io/address/0x2c51daecf702f2afe3abee2cc84570ee17f75650 (I've tried to call update() several times).
Answer: It looks like the query is working on the Oraclize Test site. You can see it working here. It has a request like:
json(https://api.kraken.com/0/public/Ticker?pair=ETHXBT).result.XETHXXBT.c[0]

with a response of 0.068000
It seems your syntax is incorrect when you use .result.XETHXXBT.c.0 instead of .result.XETHXXBT.c[0] since the result is an array and not a key named 0
Answer: The issue was that the ropsten test network I was using was having issues. I believe the code I posted should normally run fine.


Acne pimples on face

Question: I have acne on my face from few years.i have used so many things for this take medicines from skin specialist but not useful at all kindly suggest me anything. I have oily skin.
Comment: I didn't make the rules, and I'm sorry that you perceived my comment as unfriendly and unhelpful - from my perspective it was merely factual; lifehacks is frequently treated as a dumping ground for queries that don't have an obviously more relevant community. This diminishes the experience for all and can cause communities to be closed. For health issues we specifically recommend you contact a qualified healthcare provider who can look at you in person; giving health advice over the internet based on a limited amateur description of symptoms is extremely unwise and no doctor would condone it
Comment: Hi and welcome to the site. Just wanted to point out that Health tips are outside the scope of lifehacks.se, I'm afraid - this question would probably be better off posed on another site in the .stackexchange network
Comment: @user5948 Have you tried using a Clarisonic? That product did more for me than anything else in getting rid of acne. Don't buy a knock off brand; buy the real thing. Use twice x day. They are worth the money.
Answer: There are many factors that play into how much acne one has (including many that are likely beyond your control), but there are a few general guidelines that may help.

Wash your face twice daily (morning and night). The type of cleanser you use is important, but not as important as consistently washing your face. Try using a soap or face wash that targets oily skin.
Use clean cloths on your face. Change your pillowcases regularly, and avoid reusing towels on your face. Similarly, don't use a towel on your face that you use on other parts of your body, as this can unnecessarily spread bacteria.
Exercises, eat right, and drink water. This is good advice in general, but it is also helpful for your overall skin health. Avoid oily foods if you have oily skin.
Never sleep with makeup on. If you wear makeup, use a separate makeup remover (other than just soap) and follow up with a normal face cleanse.
Try other products. It can take up to six weeks for a product to begin working, so it may help to stick with one product for a while. Additionally, you may want to try face products other than soap. Finding the right products for exfoliating, toning, and moisturizing can be a challenge, but incorporating these extra steps into your face routine can be helpful even if they are generic drugstore brands.
Check with your physician about other health concerns. If your acne is "normal" for your age, chances are you can help the problem by using some of the aforementioned steps. If it seems unusual, you may have a hormone imbalance and possible other issues. If you suspect something isn't right, it's always better to consult with an expert!
Comment: I hear your frustration.  Our son got the acne gene from both of us and has been struggling for years to find a solution that works. Your oily skin sounds like my son's. He could wash many times a day, change bedding every day and there would be no difference.  However, there is hope. Maybe......  first rule out allergic reaction as acne can be a result of a reaction to food or something that you come in contact with.   With our son , the next step is supplements. There are many out there that "might" help. Everyone has different skin.  Collegen seems to be what is working for my son.
Answer: Clean your hands and face as often as possible.
Stop touching your face with your fingers all the time.
Use a clean pillow-case. Clean it more often.
Stop eating potato chips and other greasy/salty snacks.
Drink a lot of water all the time. (A LOT) If you don't like to drink water, drink it until you like it. The more the better, seriously. Poisoning yourself with "too much water" is very difficult. Water will dilute the pollution inside you and flush the bad stuff out.
If you do eat salty and greasy foods, compensate by drinking a lot of water after.
Drink water when you drink alcohol. (one glass of beer, one glass of water) This will not prevent you from being drunk, don't worry. It does prevent hangover however.
If you are a teenager, consider that you are in the worst age for this, time will help.
There might not be a miracle solution for you but all these can help.
If you are over 20 years old and still experience acne problems even with applying these methods, consider talking to a doctor.
Source: my own experience. When I stopped eating BBQ chips every night before sleep, it magically went away.
Edit: Noticed from your profile that you work with computers, like me. A lot of people in this field sit all day long and can develop unhealthy habits. I don't know if that is your case. Try to be healthy. If you are fat and eat a lot of fast-foods, the acne might be only one symptom of a general unhealthy lifestyle. You cannot correct just that one symptom, you need to address the root cause and be more healthy overall. Try to do a MINIMUM of exercise EVERY day, just walking 20 mins is something, compared to nothing at all.

Acne pimples on face


Must a programmer learn text editors like Emacs and Vim? How important are they?

Question: I have been writing code so far in conventional text editors that come with the OS so far or use an IDE in some cases. I know there are some advanced text editors like Emacs and Vim available solely for the purpose of coders. How important are they really? Should a programmer dealing with PHP, Python etc. learn these editors? What are the advantages that they provide over conventional editors like Notepad++, Scribes etc.?
Comment: @OJ:  There are few systems that will support programming that vim can't be installed on.  There are doubtless many where it isn't installed, and there are reasons why you might not want to install it.  There may be policies about installing software, you may want to edit something right now, you may not have a fast internet connection or a handy installation CD or thumb drive, or you may just be touching the system briefly and you don't want to install something just for a little use by one person.
Comment: For the young ones amongst us - vi is the standard editor under Unix.  vim is a modern clone which is frequently installed instead on Linux systems.  It is a tribute to vim that the differences in the non-GUI version are hard to spot.  Stuff like how much you can undo and such.
Comment: "Must a programmer learn text editors like Emacs and Vim?" No. I feel obliged to qualify that, but actually it doesn't need it. So I won't.
Comment: See this thread: [What are the efficiencies afforded by Emacs or Vim vs Eclipse?](http://stackoverflow.com/questions/1346820/what-are-the-efficiencies-afforded-by-emacs-or-vim-vs-eclipse)
Comment: I don't know why people are going around closing questions two years later, but this isn't a dup, at least of the question given.  It's actually asking the exact opposite.
Answer: A programmer should not necessarily learn a lot of tools, but learn a few and learn them well.
Emacs and vim each have their distinct strengths but unless you use them a lot on a regular basis you will not benefit enough from them, I think.  Especially not if you are a learning programmer.
You will, however benefit from a good IDE, but you should also be able to do real work just given a plain, simple editor.
Comment: I actually found that having learned Emacs as a (relative) beginner, life was much easier: whenever I wanted to use a shiny new language (say Haskell), I could still use the same editor. Before, I had trouble switching between random languages because of the different IDEs I tried to use.
Comment: The problem with vim or emacs for a programming beginner is that if you want to learn how use (say) vim, you now have two problems: learning to write code, and learning to write code *in vim*. That said, those who persist and *do* learn will be greatly rewarded.
Comment: @Tikhon, perhaps it is so long ago that you cannot remember the learning curve of Emacs?
Comment: I was a high school student then (last year) and became very comfortable with it in a single semester. Make of that what you will.
Comment: Daily use isn't necessary to justify learning vim or emacs.  I use vim fairly frequently, but days can pass when I don't use it.  I still get a great deal of value from knowing how to use it.  A beginning programmer probably should learn programming first, and vim or emacs later, but the payoff lasts the rest of your career.
Comment: And for those in doubt, I've spent plenty of time with both Emacs and vim (and vi/nvi/etc).  I am considering the situation as seen from a beginners point of view.
Answer: Vim is a really good tool once you familiarize yourself with it.
It starts up faster than any IDE or text editor I've used, and it has syntax highlighting and it indents the code correctly in most cases.
It also helps you focus on the coding process itself, you won't be using the mouse at all to deal with it, that'll save you a lot of time when you're just writing code.
It has a wealth of plugins for whatever it is you're doing, as well.
I haven't used emacs to be honest, but I'm sure there are people here who like it, I personally don't like having to press Ctrl or Alt all the time.
Edit
Vim's usefulness also depends on what you're writing.
If you're an API developer (Java, C#...etc) you'll most probably be more comfortable with an IDE.
But if you write scripts (Bash, Perl...etc), Vim might be the way to go, since you need to write something fast, Vim is fast, and does everything you need.
Comment: And I despise hitting escape all the time. Whats the point.
Comment: @tyler if you have multi GB files you're doing it wrong.
Comment: Vim is also an excellent environment for more complex work. (I typically work in rather large codebases in Vim, and frequently have dozens of files open in various windows and tabs, and can even do a good deal of debugging there.)
Comment: @greyfade yes, but I'm not comfortable with not having autocompletion when dealing with large APIs like when coding Java web applications, which will involve external APIs as well as the language's standard library, which in Java's case is huge
Comment: Another advantage of vi/vim is that it does a much better job with multi-GB files than other editors.
Comment: @Mahmoud There's always eclim (Though I've never tried it, so have no idea how practical it is)
Comment: @Matt looks interesting, but I've never been a fan of eclipse anyway.
Comment: @Mahmoud Hossam: Not having autocomplete? I've been using Omnicomplete for years.
Comment: @greyfade it looks like a hassle to get it to work though, according to [this](http://vim.wikia.com/wiki/Omni_completion) article, it doesn't work out of the box.
Comment: @Mahmoud Hossam: Once you set it up, you're more or less done. Though if you use something like ctags, you only have to regenerate your tags file(s) periodically, which you can obviously automate.
Comment: When I started learning vim I nearly smashed my escape key through the floor.  But then I got the hang of it and realized the truism - most of the time, as a programmer, you really are in command mode  - you're moving around, copying and pasting, searching, etc.  So command mode is that default and it works well.  This feeling only comes after quite a bit of practice.
Answer: Importance of vi is that you will always find it on any flavor of UNIX (standard both in SysV and BSD flavors) or UNIX-like system. Note however it might be original vi, not vim. You're not guaranteed to have any other editor installed. Also in Linux it's in /bin, so it's available even if /usr failed to mount.
Comment: Another editor that's (was?) always available is `ed`. Quite handy when connecting to a server via unreliable modem/POTS with low baud rate.
Comment: @Bavarious:  And, with experience with several different editors named "ed" on several different systems, I've adopted a rule:  **Never** use an editor called "ed".
Comment: @Bavarious In fact, vi was originally written as the VIsual mode for a line editor called ex, which in turn is an advanced version of ed.
Comment: `vi` is superset of `ed`
Comment: I always found `nano` editor coming from windows really friendly and its mainly in all dist's
Answer: Are you a fast touch typist?  Do you often wish for more keyboard shortcuts to make edits?  Does the time you spend editing interrupt your train of thought?  Do you find little things about your editor that you wish you could customize to work just the way you like it?  Do you not mind spending potentially a lot of effort up front if it means it will save you more time and effort in the long run?  Are you unbothered by people considering you anachronistic?  If so, then vim may be a good fit for you.
Do you prefer to be able to figure out your editor without reading the manual, even if that means fewer features?  Are you more comfortable using what everyone else in the office is using?  Do you use the mouse for everything?  If so, then vim may not be a good fit for you.
Comment: +1 - Great objective answer that gives both perspectives of which is better.
Comment: Everyone in our office uses vim. I do not find it anachronistic at all.
Answer: I think that learning Emacs (and probably Vim as well) is very useful. Why? Simple: I can use the same exceptionally capable editor for more or less everything I do.
This is great because I am a student, constantly learning how to use shiny new things. This year, I played around with Haskell, did a ton of JavaScript, used Scheme, wrote some Java, screwed around with Perl, worked on a web site... Emacs was great for all of this.
In the past, I had some problems with different languages: I would pick up Perl or Python, but could not find a good editor for either. Now, I know I can always use Emacs. Of course, sometimes Emacs does not have all the features I want, but it always has enough features off the bat to use for quick projects. For longer projects, it may need some customization, but the time taken to do that is probably equal to getting and learning a new IDE.
In short: Emacs is great because it supports so many different languages, and is powerful enough even without support for a specific language to make life much better.
Answer: There are at least three reasons why a newly minted programmer might choose to spend some time learning emacs and vi:

tradition: Both vi and emacs have been around since Moses picked up his output on stone tablets. In fact, God himself may have invented either vi or emacs, and the devil the other, but you'll get different answers as to who invented which depending on who you ask. (You've heard that it's a religious argument, right?) At any rate, these two editors have enabled quite a bit of history, and stories and jokes involving them abound. You may feel unable to understand your roots without some knowledge of both. For example:

How many vi users does it take to change a lightbulb?
ne, as long as he doesn't forget to enter 'insert' mode first.*

inertia: There are a lot of people out there who have emacs and/or vi keystrokes burned into their neurons like the high score on a Defender machine. I don't think that anyone would hold up either editor as a shining example of modern user interface design, but since so many people already know the commands, newer editors often build in support for vi and/or emacs commands. MacOS X is perhaps the best example of this: you can use a surprising number of common emacs commands in any Cocoa-based application (unless you're one of those people and install a vi-based input manager). Many IDEs and text editors on all major platforms offer key bindings for vi and/or emacs, and probably will for a long time to come. So, just as you've learned to type on a QWERTY keyboard, you'll probably also pick up some commands derived from an ancient text editor whether you know it or not.
power: I'm not so sure about vi, but it's safe to say that there are very few editors that come close to the power and flexibility available in emacs. Don't like the way something works? You can change it. Don't feel like dropping out of your editor to use the command line? No problem -- you can do everything you need right inside emacs. You'll need to spend a lot of time studying in the swamps of Dagobah to learn to tap into all that power, but some people may find that worthwhile, perhaps even just for its own sake. vi is more like a Leatherman tool hanging on your belt: versatile, always ready, and useable for all sorts of things.

Now then, is it important to learn vi and/or emacs? I'd say that it's useful to know something about both of them, especially so that you know at least a bit if you ever find yourself needing to use them (you might). But not knowing them won't necessarily hold you back. It's much more important to know how to wield the tools that you use daily as effectively as possible.
* That's not a typo -- you'll get it after you spend your first hour with vi.
Answer: No
If you want to learn how to use them, don't do it in a production environment. Do it on your downtime or time set aside specifically to get used to writing code on them. When you get more experience, introduce it to your environment but keep the program you are used to near by. I kept frontpage near by when I decided to transfer to a pure text editor, until I was confident enough that I no longer needed it.
Comment: And keep a cheat sheet handy :-)
Comment: +1 Do not learn in production environments. I have seen outages because of ineptness with a text editor.
Answer: If you need to learn an editor for programming, make it emacs.  Why?
If I need to make an rpm and I open emacs, and tell it to find a file which happens to end with the extension .spec
WHAM! A skeleton file appears with all the tags and macros already filled in with text color-coded.
And if I want to submit to my favorite version control,
esc-x load-library mercurial (or git or svn) puts emacs in the mood to drop down the right commands from its version control menu or to recognize the commands like ctrl-x v v to check in or out code from a repository, and to do everything one can do with a repository.
Optic fatigue occurs when one stares at the same colors for too long.  I use konsole for terminal windows and change the colors frequently.  With emacs not in a terminal window, I have more than 50 color themes to choose from, some of them comfortably low contrast, like Alice Blue, and some eye-stabbing like euphoria for when I need to stay awake.
I code a lot of python.  When I need to test some coding for syntax, I don't leave emacs.  I start the Python interpreter, and the screen splits, then I save my python file and import it to the interpreter to check syntax--an error will be readily apparent, and I can fix it immediatelty.  When I am done, I can switch to an unsplit window and continue work.
Some folk say use vi, and I do use it on some older SUN systems...  I have a regular rhythm--hit i and insert a char then hit escape and hit i again and type the next char...  (barely better than ed, but it is what's available).
Usually my first install on any new system is zile.  GNU zile is emacs without all the window dressing like browsing and email and irc and colors, just a C-coded binary that works in about 100k and uses emacs keycodes.
If emacs were as onerous as most try to make it sound, it should be amazing that so many folk were gluttons for self-flagellation by making emacs-like editors.  MINCE Is Not Complete Emacs, the 31 flavors of micro-emacs, Jed, Zile, Joe and an oddball python coding or two plus web-based YMacs, are all emacsen.  peppy http://peppy.flipturn.org/ is a different take, using emacs keycodes and coded in Python and it will edit nigh on everything, including chunks of binary data, and it has dozens of modes for programming languages, but its keycoding paradigm is emacsen.
YEah, emacs is worth learning, and so is vi.  Of the rest, maybe Eclipse is as useful, if you can stand the hoggishness of its many inserts.  And if you need something REALLY small, lightweight, and fast, check out e3.  The x86 version is written in assembler and serves many keycode sets including Emacs and Vi. https://sites.google.com/site/e3editor/
And oh yes, I open emacs, type 17 pages, and BLAP!  Lightning strikes and my power goes out.  When power is restored, I look at the work and discover I lost the last 7 characters I typed....  And if I decide to follow the "recover crashed session" procedure, I can reduce it to 2 lost.
Python code doesn't believe in indentation, it DEPENDS on them.  Emacs is aware of that and makes sure your indentation is proper.  But if you decide to remove an "if" you will have a whole region in the wrong indentation status.  With emacs you fix that by:
ctrl-space and arrow keys to highlight the region
ctrl-c < to outdent all the highlighted code. (ctrl-c > indents it again, correctly).
I think I have used more than 60 editors, and still the one I come back to is emacs, not because I can get function code stubs in C or proper indentation or color-coding, but because I can customize it beyond its already awesome capabilities.  Richard Stallman's brainchild was adapted by so many...
Comment: Lightning? And your file system is in that good shape afterwards? Well, it does not always end as well.
Answer: Nowadays popularity of various kinds editor worship most likely comes from Pragmatic Programmer book,
or, to be precise, from readers who mindlessly crammed Chapter 3 Basic Tools -> Power Editing -> One Editor but totally missed the key (pragmatic!) takeaway laid out in Preface chapter:

There are no easy answers. There is no such thing as a best solution, be it a tool, a language, or an operating system. There can only be systems that are more appropriate in a particular set of circumstances.
This is where pragmatism comes in. You shouldn't be wedded to any particular technology, but have a broad enough background and experience base to allow you to choose good solutions in particular situations...
You adjust your approach to suit the current circumstances and environment. You judge the relative importance of all the factors affecting a project and use your experience to produce appropriate solutions. And you do this continuously as the work progresses.

If one gets the general understanding like above, this alone makes the book worth reading. Main idea to keep in mind is one that authors stated clearly and unambiguously, "there is no such thing as a best solution".
Answer: Neither emacs nor vi are solely meant for coding; they just happen to support features that make writing code a little easier.
vi's sole virtue is its ubiquity; any Unix or Linux-based system is going to have an implementation of vi.  It's light-years friendlier than TECO was, but so's using an Etch-a-Sketch.  That said, vi is my primary editing tool in a terminal session, simply because I never had the bandwidth to learn it and emacs at the same time (and emacs has too damned many keycode combinations).
You don't need to learn either tool; there are other quality text editors out there that support many of the same features in a friendlier format.
Comment: "vi's sole virtue is its ubiquity" - I've seen some negative things said about vi/vim before but this is a bit extreme.  It's like comparing it to MS-DOS edit or Windows Notepad.  Surely it has other positive features, like very fast start-up, comprehensive syntax highlighting, limitless configurability and scriptability, extensive use of keyboard shortcuts, multiple buffers, split screen, I'm sure there's more...
Comment: I'm an extreme kind of guy.
Comment: I would not say the ubiquity is vi's SOLE virture. With vi (and maybe emacs as well) you can edit text files without having to move your basic hand position. This makes banging out text and code faster (once you have mastered all the magic codes...). This is a mixed blessing. It increases your risk for carpal tunnel syndrome, but greatly reduces your risk of mouse shoulder.
Answer: You don't need to learn Vi or Emacs, you need to learn your tools.
Imagine a sniper who doesn't know well the downsides and capabilities of his rifle, he would not be a good sniper ? Would him ?
So go ahead and find an editor you like, you might like Emacs, Vim, Textmate, Sublime Text... heck, maybe you don't like any of them and you are OK with Nano, but what matters is that you are comfortable with your tools.
Answer: First things first. VIM is more productive for programming than Eclipse or . Your personal productity in VIM may be abysmal, but the potential cap of VIM is much higher. This is a fact.
VIM is a martial art. It feels unnatural when you first use it. And you can't even make it work. It takes years of practice to gradually become productive. You focus on mastering a little detail at first. Slowly all these bits you master add up until text is flowing effortlessly out of your finger tips onto the screen. Complicated edits that would make your co-worker sigh will jump from your hands before he can finish his exhale. There are few people who can use VIM. Fewer who can use it productivley. And you may never meet a master in your life time. But they are rumored to exist.
VIM is designed to keeep your hands on home-row. Moving your hand from the keyboard to the mouse is demoralizing. It's a gross motor movement. Moving your arm has a phsycological effect that hurts your motivation. Using VIM, someone could bolt your wrists onto the keyboard and you could still easily open up files, split windows, open tabs, build the project, search/replace, change fonts, change colors, etc. And all at lightning speed.
VIM is modal. That means you don't have to do complex key combinations where you hold down control+shift+Key. This hurts your hands in the long run. Instead you execute commands. There is no need for key combos to due to the modal nature.
We store data in our memory like computers do. Our memory can only hold a few values at a time. See how many distinct integers you can hold in your head before they start to slip away. We overcome this human limitation by writing stuff down. If data falls out of our memory we can easily look at what we wrote down to get it back. If your time is spent doing gross motor, physical things you are losing time that could have been spent on processing data in your brain. You want your mind to flow onto the screen without any effort at all. It may not sound like much but VIM's ability to effortlessly transfer what is in your mind to the screen is a BIG productivity boost. It's hard to put in words what I'm trying to say.
VIM supports code completion. Both textual and look-up based. It can pull text from mulitple files. Anything you desire can be had in VIM. Either make it yourself or use something someone else cooked up.
VIM supports goign to definitions with ctags. You can also find all references of an item. Again, anything you desire can be had in VIM.
The scripting of VIM is huge. You can download or create thousands of color schemes and change colors in an instant.  Try to change fonts or colors in Microsoft Visual Studio and it will hang for 20 seconds while it loads data. It won't let you store color schemes and you must spend 30 minutes tweaking your colors and fonts every time you want a change of scenery. In VIM you can set line spacing to zero to fit more lines of code on the screen. I get over 80 lines. Visual studio uses 2 pixels of spacing for every line and you can't adjust it!!! Less lines = more scrolling = less productivity = forced to use small fonts for more lines = eye strain.
Split windows are opened in an instnat in VIM. It's usefull when you need to look at data in one section of the code that's far from the place you are typing (or in a different file). You don't have to spend time resizing windows, or worry about GUI windows overlapping each other and falling behind each other. Un-related code windows can be opened in tabs as to not take up screen space, but allow quick switching.
VIM as an IDE: http://www.youtube.com/watch?v=MQy2rVOf-z0&feature=fvwrel
VIM the revenge: http://www.youtube.com/watch?v=lQNFfhC4QI8
Comment: How can vim be "more productive for programming" when, according to you, it takes years to learn? Beyond that, your answer only explains what you like about vim; it really doesn't address the OP's question.


Most Important Features for a CMS

Question: Suppose someone is building you a CMS (Content Management System) from scratch.  What are the most important features to include and why?
Answer:
security - OWASP Top 10
user management & user roles
action and view permissions
content versioning and audit
some form of workflow and notifications
i18n support on literals and object versions
normalized database schema design
some form of content import-export
assets management and thumbnail generation for uploads
Valid XHTML (compressed with GZIP)
Rich text editing (e.g FCKeditor) which generates accessible markup
Valid and minified CSS and javascript (e.g using YUI)
automatically generated sitemaps.org document
integration with Google Analytics
automatic RSS feeds
open search support
print css and/or print versions of content
SEO consideration for duplicate content (e.g use of canonical tag)
Answer: I think from a developer's perspective it would be an open modular architecture. IMHO there are always things to add which the CMS platform isn't providing out of the box. Also, it should be database-based.
Existing modules should cover the most important tasks: news, contacts, documents, forums, shop, survey, events, image gallery, navigation, links, fulltext-search, login, newsletter, etc.
From the user's perspective I think that the content editor (WYSIWYG) is the most important piece. The ability to edit inside the "live" page is a great feature. Upload of images with automated resizing and the upload of files should be easy.
The existence of page/control and website templates is also very helpful when you're starting with a CMS. Versioning of documents/pages is also a often required feature and a work-flow engine, where there are authors who create content and editors who are allowed to unlock it.
RSS syndication is another important feature that should be available in a modern CMS.
For international site it very important that the CMS had some sort of built-in multi-lingual support.
Then I think a good CMS nowadays must provide tools for Search Enginge Optimization, e.g. there must be a way to define and insert search engine friendly URLs.
Answer: Not mentioned already: A CMS system should easily integrate into an existing software infrastucture, so interoparability is a strong requirement.
Example: If your CMS supported WebDav, you win Microsoft Office as editing tools without any extra expenses.
Answer: My number one requirement when choosing a CMS system is the ability to skin it easily and control the markup.
Users can be really fussy about getting the layout EXACTLY as they want.
Answer: 1) WYSIWYG editor.  Being able to edit HTML content as if it were in Microsoft Word.  That includs the ability to upload your own images.
2) Creating new pages without query strings ie) not 'pages.aspx?pageid=5' but 'contact.aspx'
3) Additional features such as news, photo gallery, blog, user management, etc...
Personally I really like the CMS starter kit Microsoft has available on codeplex.  It is very well done and uses XML file storage so it doesn't need a database!
Answer: In addition to the things that others have mentioned:
Caching
If you page comprises lots of "pieces" - e.g.  a Banner pane, Left pane, Main pane, Right pane and Footer pane, and perhaps each of those will have multiple "widgets" in them, then the effort of constructing the page becomes significant (both in database calls, and in rendering at the web server).  Having some intelligent caching that is able to detect when any of the underlying content blocks has changed will make a big different to performance
CMS Matrix may be a useful comparison resource of existing CMS products
Answer: The features you need the most will naturally depend on how the CMS is going to be used, and by whom. For some, licensing will be the greatest issue, while for others, some obscure requirement like support for TIFF files could be the thing.
If you want en extensive list of CMS features, take a look at CMS Feature Lists
Answer: When working with clients, I often heard a number of requirements that, in my opinion, had little to do with what a modern CMS really needs. Far too often emphasis was on features that should have been in the domain of template designers, such as support for responsive design (whatever that really means), the ability to add brand elements etc.
I compiled a list of the top 5 features a modern CMS needs at http://www.simoahava.com/content-management/modern-cms-top-5-features/
Modular architecture and strong security are the most important features from a technical standpoint. Complete control over content, source code and the software solution itself are all huge perks for any CMS.
Simo Ahava

Most Important Features for a CMS


Dense distributed matrix

Question: A dense matrix is distributed for parallel computation column-wise, then multiplied from left & right by sparse matrices. What would be appropriate c++ libraries for these tasks?
Answer: For dense distributed memory linear algebra, you can't do better than Elemental these days. Although, it does not currently handle sparse matrices, I believe. Dense-sparse operations will probably require you to do some custom coding.
Comment: You should consider requesting this feature in Elemental.  See http://libelemental.org/help/ for contact info.
Comment: ... so the question is still open.
Comment: I second Jeff's suggestion. To my knowledge, there is no existing library for the exact functionality you described. Elemental is the closest.
Comment: @VictorLiu: I am wondering, what "can't do better" means. Are there supporting benchmarks?
Comment: "Can't do better" as in this is the closest match to your requirements in terms of features (distributed,dense). It is also probably the fastest such library.
Comment: Now, I'm wondering about "probably".
Answer: The ScaLAPACK library is designed for dense matrix operations on distributed memory machines. It will still work on a shared-memory machine though, provided that you have MPI installed (installation requires mpicc and mpif77 compilers on linux). I haven't used it before, so I can't attest to its user-friendliness.
http://www.netlib.org/scalapack/
Comment: ScaLAPACK is not a C++ library.
Answer: I would day it definitely depends on the parallelization architecture and what you want. If using shared memory CPU's, probably Elemental even though I have not used it. Note that PETSc also has tools for sparse matrices. But if you really need it to go as fast as you can, and the sparse matrices have some known structure that you can take advantage of, then I would write the whole thing using MPI. In my experience that is always much faster, but also requires more work. So it depends on your needs and time to code.
If you want to go with GPU's, nvidia has a sparse matrix library that you could try using CUDA.
CUDA 5 also let's you do some kind of mpi+cuda, so you can have a clusters of gpu's, but I have no idea if the sparse-matrix libraries are capable of that but I don't see why not. It's worth to take a look at. But again, if you need it to fly, I would make my own code.

Dense distributed matrix


In which languages can I take the theory exam for driving license in Germany?

Question: As far as I know it's possible to take the theory exam for your driving license in a foreign language, but I don't know in which languages. Does it cost more than the exam in German?
Answer: According to this official answer from the ministry for economic affairs, work and transport of Lower Saxony to a question by a local MP, the exam has to be offered in 11 languages:

Abweichend davon kann die Prüfung auch in folgenden 11 Fremdsprachen abgelegt werden: Englisch, Französisch, Griechisch, Italienisch, Kroatisch, Polnisch, Portugiesisch, Rumänisch, Russisch, Spanisch und Türkisch.

Which is in English:

Notwithstanding this, the exam can be taken in the following 11 foreign languages: English, French, Greek, Italian, Croatian, Polish, Portuguese, Romanian, Russian, Spanish and Turkish.

This follows from a federal regulation. In the past, individual states could also offer to pass the exam in other languages using an interpreter but Lower Saxony apparently stopped doing it over concerns about cheating.
Answer: @GaLa's answer contains all of the languages that are accepted when doing the test:

Arabic
Croatian
English
French
German
Greek
Italian
Polish
Portuguese
Romanian
Russian
Spanish
Turkish

However you can buy the teaching material in the following additional languages. You won't be able to take the test in these languages however.

Albanian
Afghan (Dari)
Bulgarian
Chinese
Hungarian
Indian (Punjabi)
Persian
Thai
Urdu
Vietnamese
Comment: Small update for 2021: Arabic is also an option
Comment: @nicbou For the examination, or for the teaching materials?
Comment: For the examination. The teaching materials are usually exactly the same, verbatim. When I took the test (2017), the questions were the same, word for word. This is good, because the translations are horrendous.

In my experience, you need to know the questions/answers by heart, because the sentences are often confusing and contradictory.
Answer: You can opt in to have an exam in any of the following languages:

English
Turkish
Polish
Russian
Serbocroatian

There might be more supported languages now, the list is just from the top of my head, it might have been updated.
Although the actual test costs the same, the books/sites used to prepare for the tests usually charge extra if you need a version in another language. You just need to make sure that you specify the language when you go to the Führerscheinstelle to apply.
Also, since most of the test preparation material is sold through driving schools, make sure to ask them if they have a version in your language, or choose another school that have it.
Comment: Do you know a source for this?
Answer:
Although the actual test costs the same, the books/sites used to prepare for the tests usually charge extra if you need a version in another language.

At least in Hessen, TÜV (the state structure where you take the theory exam) does not charge anything extra  if you take the exam in a foreign language. However some driving schools do charge extra for that, which is illegal. If it is the case, you can make a complaint to your local Regierungspräsidium.
Comment: Yes, TÜV doesn't charge extra, driving school doesn't charge extra, but the books are more expensive, and software costs a bit extra, which is not illegal.
Comment: Costs of software does not always depend on the languages offered. E.g., my driving school just recommended the same online system for everybody, and there were 7 different languages offered. However, if you need a special language, which is rarely offered, you might need to pay a bit extra for that software, but not necessarily because of the language support itself.
Answer: As of 2021, the exam is available in 13 languages: Arabic, English, French, German, Greek, Italian, Croatian, Polish, Portuguese, Romanian, Russian, Spanish and Turkish.
Sources:

Berlin.de (German)
All About Berlin (English)
TÜV Süd (German)
Gut Lernen (German)