array length in JS

Question: var a = [1,4,5];
var e = a.length--;

Here e variable will contain 5. But if I do:
var e = a.length-=1;

Here e will contain 2 the number of elements array.
So the first is a language 'tip' to simulate a pop() array methods?
In the language syntax doing:
a--

or
a-=1

is semantically the same.
Comment: Where is the question in your post ?
Comment: So the first is a language 'tip' to simulate a pop() array methods?
Answer: var a = [1, 4, 5];
var e = a.length--;

is the same as
var a = [1, 4, 5];
var e = a.length;
a.length = a.length - 1;

whereas
 var a = [1, 4, 5];
 var e = a.length -= 1;

is the same as
var a = [1, 4, 5];
a.length = a.length - 1;
var e = a.length;

and
var a = [1, 4, 5];
var e = --a.length;

In other words: x-- returns the value before decreasing whereas --x (and x -= 1) returns the value after decreasing. All these code snippets pop the last element off the array a.
Note that in the first example, e = a.length--, e will have the value 3, not 5, therefore it is not the same as a.pop().
Answer: This is a basic misconception: If you evaluate a++, a will be evaluated and then incremented while ++a or a+=1 will be incremented first, then evaluated.
In most cases it's better to write these kinds of statements in a more verbose manner because they can quickly lead to confusion about what is going on while not gaining anything (most compilers / interpreters will optimize this anyway).
Answer: That's not what I get.
Rather, I get the expected result. e = 3 in the first instance, and e = 2 in the second.
In the first case, a.length is initially 3 (because javascript arrays are sparse). using the post-decrement, this value (3) is first assigned to e, then a.length is decremented (funny this is possible, actually).
In the second case, 1 is subtracted from 3 to make 2, which is then assigned to e.
So I don't think there's anything fancy going on, really.
Answer: var a = [1,4,5];
var e = a.length--;

e will not contain 5. It will contain 3.
The -- postix decrement operator will make no difference here. a.length is 3. The second statement translates as:

retrieve array length  (result: 3)
store result in variable named "e"
decrement array length (this step has no effect on the overall outcome for this standalone sample)

Whereas:
var a = [1,4,5];
var e = a.length-=1;

here e will contain 2.
The second statement translates as

retrieve array length (result: 3)
decrement array length (result: 2)
store result in variable named "e"

In any case, you are messing with the array.length property, which you shouldn't do. It causes the kind of nasty bug that is hard to track down because it is result of a side effect you probably did not intend or think of.
Answer: oh yes I read this from the book : Object Oriented Javascript at page 112

The push() method appends a new element at the end of the array. The pop() method removes the last element. a.push('new') works just like a[a.length] = 'new' and a.pop() is the same as a.length--.

and without try the code I post the question!!!
Sorry. So I think this is a book error because pop() returns the last element where
a.length-- shrink the array but not returning the element but the array lenght -1

array length in JS


is usb booting safe and will information go to hard drive?

Question: I would like to boot from usb but is my hard drive totally safe if I am booting from usb drive and can viruses get from usb drive to hard drive?
Comment: It depends on where you got the USB from. Look up boot sector virus ...
Answer: I'm assuming you're referring to running linux from a liveusb here.
Your hard drive will have to be mounted before the live boot would be able to even touch it.
If you burn any standard Linux live ISO to the usb drive or to a CD, such as Ubuntu, GNONE, Elementary OS (these are just some examples), they don't mount drives/partitions automatically unless you run their installers. You can also manually mount the drives/partitions by opening them in the distribution's file manager or by running some mount terminal commands.
Can a virus infect your hard drive? It is possible, but you'd have to be pretty reckless about what you give root access to. If you're super paranoid you could just take the hard drive out whilst you're running a live boot, but that's just overkill.
In a nutshell, you are safe, and nothing will happen to your hard drive as long as you don't install the Linux distribution or run some file destroying commands on your hard drive partitions.
Comment: So if I instal ubuntu like in this video https://youtu.be/U-7chlCn6yk (3.50) will it instal ubuntu on my hard drive or usb drive?
Comment: Rufus burns an ISO onto your USB drive. It cannot install it directly onto your hard drive.


What is the frequency of drop items at the end of each game?

Question: Every week I see how other players obtain items at the ends of the games. For example, parts of armor sets. I have played many hours of Counter Strike Go and in that game the loot refreshes every week. But I don't know if this system is the same in Dota 2.
Answer: From my personal experience, I can say that there is no loot refresh system in Dota 2. The stuff is awarded randomly. Last week I've got like 2 pieces of different item sets and of different quality, but haven't got any items at all for like half a year or so.
Answer: In Dota 2 there is an Item drop system:
The item drop system is a feature that allows players to obtain cosmetic items for free through playing the game.

Notes:

After every matchmaking game, each player has a small chance to receive an item or set.
All drops in Dota 2 are solely based on time played in Dota 2 via matchmaking.
Winning, losing, or individual performance has no effect on item drop chance.

And also:
While spectating a tournament game with over 100 viewers, one or more Heroic items are randomly given out to viewers each time a memorable event occurs.
For more information about Item drop system read this.
Comment: While providing a lot of information, this doesn't address the question.
Comment: So, I shouldn't understand the question! Can you tell me what is the question? - I thought it is *What is the frequency of drop items at the end of each game?* ;).
Answer: The exact chance of getting an item at the end of the game was not disclosed by Valve but they stated:

All drops in Dota 2 are solely based on time played in Dota 2 via matchmaking.

So I guess the longer the match, the higher the chances of getting an item (something I did notice after very long games, having an increase on the number of players that usually receives items)
One thing I have noticed is that the chance is purely random and not RNG as most of the in-game chances (it does not increase if there are multiple games without receiving)


Infinite rebirth, finite kamma?

Question: If we have been transmigrating in samsara infinitely via rebirths, then doesn't that mean that kamma which we have earned too is infinite? And if so, doesn't that imply that enlightenment is imposible to reach since it would take one infinite amount of time to reach? I know this is classified as something that is unconjecturable and drives one insane, but this one is driving me curious. Any takers on this?
Answer: According to this Jainpedia page on Jain teachings on karma:

The karmas accrued over a lifetime trap the soul in the cycle of
births. The karmas mature by affecting the soul or the physical body
of its next lifetime or birth. When the body dies, the soul is born in
a different body, which is shaped by karmas from the previous birth
and the ones before that. The condition of the soul in that lifetime
is also influenced by karmas from previous incarnations. This cycle of
birth, death and life repeats endlessly while the soul has karmas
attached to it.
The soul yearns to fulfil its true nature, which it cannot do while it
is imprisoned within the cycle of rebirth. Only a soul without karma
can be liberated from the cycle of birth, reaching self-realisation.
Following the teachings of the Jinas and developing spiritually lead
to the prevention of new karmas entering the soul – saṃvara – and the
removal of existing karmas. ....
Destroying karmas that are attached to the soul requires ascetic
practices such as fasting, meditation and denying bodily needs and
comforts.

In MN 101, the Buddha debunked the following teachings of the Jains:

All the happens to a person is due to past karma
Elimination of past karma is possible by penance
Elimination of karma is possible by not accumulating new karma
With emptying of all past bad and good karma, suffering would end

In other words, the Jain way is emptying the karma account in order to end the cycle of rebirth, which is suffering.
The Buddha's path is that of the purification of the mind to end suffering, and not emptying of the karma account.
The Jain idea is that suffering is sustained by karmic balance. The Buddhist teaching is that suffering is sustained by craving and ignorance.
From MN 101:

"Mendicants, there are some ascetics and brahmins who have this
doctrine and view: 'Everything this individual
experiences—pleasurable, painful, or neutral—is because of past deeds.
So, due to eliminating past deeds by mortification, and not doing any
new deeds, there's nothing to come up in the future. With nothing to
come up in the future, deeds end. With the ending of deeds, suffering
ends. With the ending of suffering, feeling ends. And with the ending
of feeling, all suffering will have been worn away.' Such is the
doctrine of the Jain ascetics.
I've gone up to the Jain ascetics who say this and said, 'Is it really
true that this is the venerables' view?' They admitted that it is. ...
But since you don't know any of these things, it's not appropriate for
the Jain venerables to declare this.'  ...
Such is the doctrine of the Jain ascetics. Saying this, the Jain
ascetics deserve rebuke and criticism on ten legitimate grounds.
Comment: @NithinManmohan Yes. The Jain idea is that suffering is sustained by karmic balance. The Buddhist teaching is that suffering is sustained by craving and ignorance.
Comment: agree with what you said. Thanks for clarifying on that. Also kind of reminded of the zeno's paradox. It's only mathematical as it doesn't reflect the real world. So do the Jains interpret kamma and rebirth.
Answer: I'm pretty sure it's possible to have really bad karma and get enlightened anyway. There is a famous story of someone that killed many persons and got enlightened on that same life (though I think they end up killing him because of his past). The story should be easy to find, he was called Angulimala.
And I think it wouldn't be possible to accumulate infinite karma because a being with a ton of good karma would end up in a really long life in a heaven and burn that good karma away. And someone with really bad karma would get a long life in hell and burn the karma away too.
Comment: They don't end up killing him!
Answer: A determination can become inevitable or cancelled due to development. This is like a person sometime changing his plans & determinations, whereas at other times actions & determinations have a fixed determined effect that can't be changed.
Some actions cancel & override the effects of other actions and change the course of experience.
Existence occurs for this or that person because something is true, because it is true we know that existence has been and will be as long as the factor is true & in play.
An infinite past doesn't mean that it includes every possible element or factor.
ie the numbers less than 0 are infinite but they do not include any numbers higher than 0.
If everybody remembered & knew all past in-formation, this would be an impossible amount of data and would require an infinite amount of matter for storage, let alone storage if someone was to to objectify the immeasurable & incalculable by rememberance & thought then it would take an infinite amount of nutriment & time for one to do so, the universe would grow cold before one is done.
These are incalculable & immeasurable, therefore there is no counting & measuring of it, this never occurs.
There is only a counting & measuring as conception & perception of countable & measurable elements conceived of as being resultant of an indeterminate development.
The immeasurable & incalculable philosophical principles are basis for conception.
It's much like a person not acting on what he doesn't know & remember, knowing & remembering only particulars due to past development and acting on those unaware of what one is unaware but he is not exempt from the unconscious conditioning whether he knows it or not and it will come into play if there is an opening.

Infinite rebirth, finite kamma?


Differential charge existing

Question: We define current by $I=\frac{\mathrm{d}q}{\mathrm{d}t}$. Here, $\mathrm{d}q$ is the infinitesimal element of charge. But again,we know that charge is quantised meaning there is a finite value to the smallest amount of charge which is $e$. Since $\mathrm{d}q$ is infinitely small, $\mathrm{d}q<e$. Then how can $\mathrm{d}q$ charge even exist?
Comment: https://en.wikipedia.org/wiki/Fluid_mechanics#Continuum_assumption is pretty much the same situation.
Comment: Replace "electron" with "people", like walking through a door. dP/dt is the rate at which people (P) enter a building. But if you can't chop people in half then how can dP person even exist?!?!?
Answer: You're mixing up two descriptions that are, in practice, separate.
$i=dq/dt$ is usually used in macroscopic physics, when it is understood that you don't study actual individual electrons. In fact, most of the corresponding physics laws predate quantum mechanics, even predate the discovery of the electron.
In other words, whether $dq$ is the "small" charge contained in a "small" volume $dV$ or crossing a section during a "small" duration $dt$, it must be understood as containing a mesoscopic number of charge carriers (large compared to unity, small compared to $\mathcal{N}_A$).
In this context, reducing either $dV$ or $dt$ to the point that $dq$ contains only a few electrons makes you step outside the validity of those laws of physics.
Answer: The same holds true for water.  I presume you don't have problem using $d V/dt$ for the flow of a volume $V$ of water.  Yet we know that water is ultimately discrete molecules...
The point is: the discrete nature of the water molecule or the electric charge does not manifest itself much in everyday life so it's much more convenient to think of macroscopic amounts of water or charge as being continuous rather than discrete quantities.
Answer: I believe this is a nice example that there is a distinction between what a physical theory is and what the physical world is. To borrow Stephen Hawking's words,

I take the positivist viewpoint that a physical theory is just a mathematical model and that it is meaningless to ask whether it corresponds to reality. All that one can ask is that its predictions should be in agreement with observation.

The point is not whether there actually exists a quantity $\mathrm{d}q$ of charge. Classical Electrodynamics is not concerned with such fundamental questions. The point is that in a myriad of situations, one often deals with charges that can vary by very tiny amounts (for example, of the order of $e$), and when compared with the total charges these quantities are extremely small. In these situations, one can approximate these small, albeit discrete, charge changes $\Delta q$ by continuous variations $\mathrm{d} q$. One then gets access to the tools of Calculus and a lot of extremely powerful machinery that makes the computations way easier.
What if the total charges are not that large, so we are actually dealing with, e.g., one or two electrons at a time?
In these weak field limits, quantum effects might start to kick in. What happens is that, at some point, the classical description will crumble down and fail. There simply are phenomena which are not described by Classical Electrodynamics, and instead one needs to work with Quantum Electrodynamics. This is not a problem: all known physical theories have such a limit. As Anthony Zee puts in Quantum Field Theory in a Nutshell,

If anyone tries to sell you a field theory claiming that it holds up to arbitrarily high energies, you should check to see if he sold used cars for a living.

In short, there is no amount of charge $\mathrm{d}q$ in the actual Universe (at least as far as present day knowledge can say). However, this doesn't matter in Classical Electrodynamics. Classical Electrodynamics is not concerned with a fundamental description of the Universe, but rather with an adequate description of a wide range of phenomena, which do not include quantum aspects, much less the fact that charge is quantized. This is not a problem: in fact, all theories we know have similar limitations. The reason for using $\mathrm{d}q$ is that it works, up to a controlled and reasonable amount of error. Once this error grows too large for you, you'll need a better description, such as Quantum Electrodynamics.
"All magnetic phenomena are NOT due to electric charges in motion"
A similar problem to the one you mentioned was recently raised by S. Fahy and C. O'Sullivan in the American Journal Physics 90, 7 (2022). They mention how many Classical Electrodynamics books state that magnetic phenomena are due to currents, when in fact a lot of the phenomena we experience are due to electron spin, which has nothing to do with electric charges in motions. D. J. Griffiths then answers their points on American Journal Physics 90, 9 (2022), having a position that I consider similar to the one I expressed for your problem: while it is true that magnetic phenomena are due to spin, intrinsic magnetic dipoles do not fit within what is commonly known as Classical Electrodynamics. I believe these short papers (both of which are open-access) might also interest anyone interested in this post, as they discuss what I consider essentially the same problem (the limits of Classical Electrodynamics), albeit in a slightly different setting.
Answer: The mistake you are making is interpreting $dq(t)$ in the definition of current as an infinitesimal amount of charge. In the definition of current $q(t)$ denotes the instantaneous charge crossing a surface. Consequently, current $i(t)=dq(t)/dt$ through a surface is defined as the rate of charge transport through that surface.
Electric current is measured in Coulombs per second and the Coulomb equals  6.24 x 10$^{18}$ elementary charges (protons or electrons). Since the smallest amount of charge through a surface at any instant is that of a single (indivisible) electron or proton, the current for a single elementary charge through a surface per second is 1.602 x 10$^{-19}$ Ampere.
Hope this helps.
Answer: Good question, so good that Purcell and Morin address it directly in their Electricity and Magnetism text.

On an atomic scale, of course, the charge density varies enormously
from point to point; even so, it proves to be a useful concept in that
domain. However, we shall use it mainly when we are dealing with large-
scale systems, so large that a volume element $dv = dx dy dz $ can be quite
small relative to the size of our system, although still large enough to
contain many atoms or elementary charges.

I had in mind a more stirring quote, but this is the one I could track down. Maybe Griffiths or Jackson also comment on it. Anyway, suffice to say it is a good question. The usual answer is to work in the limit where things are small, but still big enough that we can still meaningfully think of continuous distributions of charge. Lucky for us this ends up not being such a delicate balance because of how dense with charged particles most materials are and how steady charge distributions are at low energies in most materials.
I could swear there is an exercise on exactly this in one of the classic texts that is meant to put your mind at ease, but I can't find it. Maybe someone else will know what I'm talking about.

Differential charge existing


Unpublished server

Question: Is it possible to setup my web server such that only certain sources can access and the public from internet has no access? i am thinking that we could just not publish our web server URL/IP to our upstream public DNS. And we give the static IP of our web server to the authorized sources to access. Of then, we will have to turn on firewall rules to allow only those sources in to our web server network. Is this thought feasible? thanks
Answer: First point: Once your server is on-line, it will be found (even without any DNS name) by robots scanning all possible IP numbers.
There are several possibilities to restrict access to your web server, including:

Protect the web server with username and password (basic autentification)
Configure the web server such that only trusted IP numbers (or IP number ranges) are allowed to access it

The manual of your web server should tell you how to do this. I recommend to do this directly in the web server configuration; using the firewall in addition is also feasible (but keep in mind what you have done and what you have to do when you want to change the rules).
Answer: How about adding basic credentials to your webserver? So it's only accessible to people who have the credentials.
Or maybe you can consider to use client side SSL certificate so only authorized user can access your webserver. At least you won't messing up with the network or firewall configurations, in case there will be some issue regarding it. This tutorial seems like a good start about it.

Unpublished server


How to trade in Pokemon Go

Question: How do I trade or add friends in Pokemon Go? Or is it not possible yet? For instance, each Pokemon has a "Transfer" option, but it seems that only gives the Pokemon to the professor, not to other players.
Answer: You cannot currently trade Pokémon between players in Pokémon Go. This may change in the future, but is not an option now.
Answer: Trading is coming to Pokemon Go in the next update with the new friend feature. You will be able to trade Pokemon with a friend that is in close proximity with you. The trade will cost stardust and Pokemon IVs will change in the trade. The higher your friend level with another player is the less stardust trading costs and the less IVs will be able to alter. If the Pokemon is caught further that 100km from the trade location trading will give extra candies. This answer is based on Rankedboosts summary of the coming features.
Comment: Yep, trading is available now with the behavior described above. See Niantic's support page for more details: https://support.pokemongo.nianticlabs.com/hc/en-us/articles/360001518407-Trading-Pok%C3%A9mon
Answer: You cant trade yet but they did put in in the trailer so hopefully they make tradeing a thing
Comment: This is really more of a comment than an answer...

How to trade in Pokemon Go


Subtraction to Addition Conversion; how important is it?

Question: Is it important to convert subtractions to addition, while simplyfing algebraic expressions (For example converting $3x-2y+7x-7y$ to $3x+(-2y)+7x+(-7y)$)? If yes, why and when?
Answer: My opinion is that it should be exercised and thereafter done mentally (not written down) as part of reading an expression. This then allows students and practitioners to directly follow the order of operations, simplifying at each step, and then in the last step recall and apply only the sign rules for addition. Note that the issue of reading/writing additions and subtractions is identical whether we discuss algebraic expressions or purely arithmetic ones.
For example, say we need to simplify $-10-(-12)+(-7)-4$. First we treat all the juxtaposed signs as multiplying and simplify to get $-10+12-7-4$. Then we can read this as, by definition, additions of positive and negative terms to get $-9$.
Note: (1) this follows the standard order of operations (multiply, then add), (2) the entire process requires only remembering the sign rules for two operations (multiply and addition), (3) at each step the expression gets shorter (notably, removing parentheses in the multiply step), and (4) in practice we don't write down the separate added terms, but should be reading it that way mentally.
When I introduce and need to explain the subtraction, then I'll write something like "$2 - 6 = -4$ because $2 +(-6) = -4$", so as to highlight that the latter is not something we'll customarily write down, but is rather part of the mental reading that we do.
A blog article I wrote about this issue: MadMath: Automatic Negatives, which motivates the structure of the quiz on "Negative Numbers" at Automatic Algebra.
Answer: Why? It much depends on the background. Here are a couple of scenarios.
You have the philosophy of "new math era" in mind in which $x-y$ should be taught as $x+(-y)$, and $-y$ as $(-1).y$.
You have used the so-called counters model to teach the addition and subtraction of positive and negative numbers. In this case, you might want your students to see $3x-2y+7x-7y$ as $3x+(-2y)+7x+(-7y)$ since then they can think of $3x$ plus $7x$ as counting the number of blue counters (representing positive), and $(-2y)$ plus $(-7y)$ as counting the number of red counters (representing negatives).
Please consider the above scenarios is just scenarios not what I am suggesting as a teaching method.
When? If the point of the question is to simplify an algebraic expression like the one you have given, I guess there would be no must unless you have a pure algebraic algebra lesson in mind. However, if the point of the question is to see a certain structure, then it might be useful to convert subtraction to addition. Here are a couple of scenarios.
consider writing $1-x+x^2-x^3+x^4- ...$ in sigma notation. We need to see it as $1+(-x)+x^2+(-x^3)+x^4+ ...$ and then as $1+(-1) x+ x^2+(-1) x^3+ x^4+ ...$.
Suppose you want to discuss with your students that an expression like $a-b+c$ (whether numeric or algebraic) can be structured in two, though equivalent, ways: $(a-b)+c$ or $a + (-b+c)$. In this case, rewriting the expression as $a+(-b)+c$ would relate the situation to the associative property. And you know,  associativity comes into play in one way or the other even when you just want to simplify an expression.
Added. Or you want to show them $x .(y-z)$ is just $x.(y+(-z))$, thus we use the distribution property for subtraction. Or $(x-y)^2$ can be seen as $(x+(-y))^2$, thus we can get the identity for the former from well-known identity for the latter.
The bottom line is your students need to see that they can and sometimes they must convert subtraction to addition though they might rarely need it explicitly for the sake of calculations
Comment: You might also use sigma notation to write the infinite sum indicated as $\Sigma_{n=0}^{\infty} (-x)^n$. That is, one aims to see it as: $(-x)^0 + (-x)^1 + (-x)^2 + (-x)^3 + (-x)^4 + \cdots$ which is slightly different from what you have written.
Answer: Understanding that $3-2=3+(-2)$ becomes relevant when learning group theory, where you need to have additive inverse elements.
Off the top of my head I can't remember really needing it before that, although I can imagine it might be important in some ways of explaining operations.
Answer: It is important to be able to understand this sort of switching around.  But, for the example shown, I don't see any reason to push this method (in general or for an exercise).  For one thing, it's a better practice to group the terms first, the x's and y's, then perform the addition or subtraction.  Don't add complexity, then simplify--it increases cognitive load and makes mistakes more likely.  So group the terms first.
For another thing, subtracting (a positive number) is probably a simpler idea (for a beginner) than adding a negative number.  If anything, other problems where you need to convert adding a negative to subtraction (the inverse of what is shown here) make more sense.  Or converting subtracting a negative to adding a positive.
I don't think the speculations about group theory and the like (e.g. order of operations having different impact than in basic arithmetic/algebra) make sense in the context of helping kids learn beginning algebra, even pre-algebra.  We will deal with the differences involved in symmetry operations when we get to that (way further down the road).  If we even get there (for a lot of the kids).


Empty statemachine base?

Question: hello I recently started using Resource editor and I have a question:I 'm trying to create a simple project just for test purposes in Resource Editor:nothing special just a Label with a hello world, but when I push "create Netbeans project" while all the projects(JavaSE,MIDP ,RIM) are created none of them are running. In normal JaVA I just get a black screen and in MIDP emulator I get a message saying "This application runs in the background".
My StateMachineBase code is this
public class StateMachineBase {
    public StateMachineBase(String s) {}
}

And My StateMachine code is this:
public StateMachine(String resFile) {
    super(resFile);
    // do not modify, write code in initVars and initialize class members there,
    // the constructor might be invoked too late due to race conditions that might occur
}

/**
 * this method should be used to initialize variables instead of
 * the constructor/class scope to avoid race conditions
 */
protected void initVars() {
}

So I'm guessing my prgramm obviously won't do anything since there is no code. What am I doing wrong? From my understanding StateMachineBase should have all the boiler code.I'm using Netbeans 6.9.1 ,Lwuit latest version  and JavaME SDK 3.0 and Nokia S60 SDK.
Thank you.
Answer: Well I shall answer my own post. Randomly I found out that if you save the res file and reopen it then it works fine. This was confirmed by Shai Almog in his blog saying that this is a bug that will be fixed in the next release.
Shai's answer to my post

Empty statemachine base?


Why do Bengalis celebrate Kali Puja during Diwali?

Question: I don't know why, during Diwali, the Bengalis celebrate Kali Puja? Why don't they worship Goddess Lakshmi and Ganesha?
Comment: I think that Goddess Kali and Raktbeej's battle's story was happened in the day of Diwali. That's why Bengalis celebrates Kali Puja during Kali Puja. I am telling this because I am himself a Bengali boy.
Comment: If the pujas in Hinduism are not based on the Vedas, so why the festival of mahashivratri was celebrated or how it came into existence ? Does it was also started by someone?
Comment: Since this question came up to the top on the main HSE  page just now, does anyone know about the Kali puja/vrat that some folks keep once a month on Amavasya ? I posted asking but didn't receive any reply so far : https://hinduism.stackexchange.com/questions/52102/amavasya-kali-puja
Answer: Not only Bengali Hindus, but Axomiya, Oriya & Maithil Hindus also do the same, following the Tāntrika injunctions.

कार्तिके कृष्णपक्षे तु पञ्चदश्यां महानिशि । आविर्भूता महाकाली योगिनीकोटिभिः सह ।। अतोऽत्र पूजनीया सा तस्मिन्नहनि मानवैः । बलिपूजादिकं सर्वं निशायां क्रियते तु यत् । तत्तदक्षयतां याति कालीविद्या प्रसीदति ।।
Mahākālī manifested on the mahāniśi of the 15th day of the dark fortnight (i.e new-moon day) in the month of Kārtika accompanied by a crore of yoginīs. So She is worshipped on that day by humans. All activities like offering animal sacrifices & conducting worship done in that night yields unperishable merit & satisfaction to Kālī. [Viśvasāra Tantra]

तुलार्के बहुले पक्षे पञ्चदश्यां महेश्वरीं । यथोपचारैः संपूज्य महानिशि नृपो भवेत् ।। शनिभौमदिने चेत्स्यात् ततः शतगुणं फलं । तत्रोभयदिने भूतयुक्तकुह्वां महानिशि । इमां यात्रां कारयित्वा चक्रवर्ती भवेन्नृपः ।।
One becomes a king by worshipping Maheśvarī on the mahāniśi of the 15th day of the dark fortnight when the Sun is in conjunction with Libra (i.e the month of Kārtika) with the pre-required articles. The merit acquired is a hundred times more if the day falls on a Saturday or Tuesday. If this festival is observed on both of those days (of the week) with the mahāniśi occuring at the   conjunction of bhūta-caturdaśī with amāvasyā, then the performer becomes an emperor. [Kālīkalpa Tantra]
Comment: Also the night of Diwali is called Kalaratri which has a special place in tantra anushthan, adding it the night when Sadhok Bamakhepa too got siddhi of maa Tara.
Answer: The scriptural reference for this practice comes from the Skanda Puran which mentions the use of firebrands in Diwali, the birth of Goddess Maharatri, as well as worship of Lakshmi on the Amavasya:

O great sages, a goddess called Mahārātri was born (appeared) on the fourteenth day (of the dark half of Āśvina). Hence those who are devoted to worship of Śakti should celebrate her festival.

When the sun is in Libra, on the nights of Caturdaśī and new-moon day, men should celebrate the festival of "showing the path unto the Pitṛs" with firebrands in their hands. The dead men and ghosts who are in hell see the path, due to this Vrata always. No doubt need be entertained in this respect by leading sages.
Answer:
History Of Kali Puja
The pujas in Hinduism are not based on the Vedas. They are based on
individual traditions. Bal Gangadhar Tilak started the Ganapati
festival in Maharashtra to foster nationalism and it has been a custom
ever since. In a similar way, Raja Krishnachandra who was the king of
Navadipa started this Bengali puja of Mahakali in the 18th century.
The tradition was carried forward by his descendants and the other
wealthy zamindar families in Bengal.
As this puja was basically under the patronage of the rich and famous,
it survived on a grand scale. Today, Kali puja is second in grandeur
only to Durga puja in Bengal.
The Myth Of Mahakali
There is always mythical story to explain our rituals or pujas. So it
is for kali puja. Once upon a time, two asuras, Sumbho and Nishumbho
plagued the Earth and the Heaven. Thus the gods prayed to Goddess
Durga who is the eternal Shakti of the Universe. To answer their
prayers, Kali was born from the forehead of Durga.
Kali attached the errant asuras with a 'khara' which is kind of
twisted sword in her hand. Once she started slaying the asuras, her
thirst for blood was aroused. She made a garland of the heads of dead
asuras and wore around her neck. Then she started slaying anyone who
came in her way. To soothe her anger, Shiva (who is her husband) lay
in her path. When she stepped on her husband in her fury, she stuck
her tongue out in regret. Her fury ended at than moment and that is
why she is portrayed with her tongue stuck out and her foot on Shiva.

Source


Interfacing Arduino with USB thermal printer

Question: I want to interface a USB thermal printer with an Arduino.  If I use a USB to UART converter so that I can connect the USB thermal printer to TX,RX for Arduino will it work or is  there other way I can use?
Comment: No, usb to uart does not work in that direction (peripheral to host).
Comment: is there any other option to connect Usb thermal printer to arduino
Comment: It depends which Arduino you use. Does the Arduino have USB host interface for the USB device?
Comment: Yes, skip the arduino and use an Raspberry pi or similar.
Answer: No you can't. USB isn't just an UART with different interface. UART over USB actually resembles only one of the USB device classes - CDC. There are ton's of others.
Second, the USB Host and USB Device are different thing. USB to UART converter are USB Device, while the PC are USB Host. USB Printer are USB Device too. You can't connect USB Device to Device (well, with some exceptions of USB OTG cases).
Even without this you don't know which protocol your printer uses. It's inside vendor drivers for the PC and OS. Do they supply "drivers" for the Arduino? No. So no, you can't as it wasn't designed to be used with Arduino.
If you need a printer for Arduino - search for the devices designed for this. Or a device with know protocol and suitable hardware interface.
Comment: @RichardtheSpacecat Adafruit for example offers Mini Thermal Receipt Printer which works over UART. And they offer library for Arduino. There are some probability that OPs printer actually have TTL UART inside which will even accept just simple ASCII text to print. But connecting to it requires some reverse engineering and knowledge, which OP seems to lack based on his question. There are same probability that it has some proprietary binary protocol over USB directly instead.
Comment: There are many embeddable thermal printer modules available from China, often with logic-level UART or RS232 interface. I happen to have got one some 2 years ago for $25. The documentation is often unavailable, however they seem to implement some standard-ish protocol used by other printers, with some features possibly missing. You'll have to find those by trial and error, should you actually need those. Thankfully, the printers often work as-is in ASCII mode, which is good enough to get at least some proof of concept working before the "smarter" modes are figured out later. Just passing by...


Is Brownian motion truly random?

Question: We say that Brownian motion is caused by the random collisions of particles. But let's consider an ionized gas; in that case, there's a nonzero net charge on the atom. Doesn't this mean the electrostatic force determines the paths the gas ions take, and hence their motion is predictable rather than random?  Even with molecules, there's still the Van der Waals force and isn't that what determines molecular motion?  So how can Brownian motion be random if particle motion is predictable?
Comment: Related: https://physics.stackexchange.com/q/739865/35952
Answer: The standard mathematical model for Brownian motion is the continuous limit of a random walk, known as a Wiener process. This model may or may not be a good fit to the observed behaviour of physical particles in a particular situation. There are certainly many scenarios in which the Brownian motion model is not a good fit.
Note that one of the assumptions of the Brownian motion model is that it is modelling the behaviour of a relative massive particle surrounded by a large number of much lighter particles. As such, it is not usually applied to individual atoms. It also assumes spherical symmetry, and once you introduce electrostatic forces you have probably broken this assumption.
Comment: Eh, I hesitate to say that the random walk is a model for Brownian motion. Sure in large $N$ limit it replicates it, but typically you derive it using probability distribution functions.
Comment: @KyleKanos Good point - technically it is a Wiener process. I have amended my answer.
Comment: Can you cite some sources saying it requires charge  symmetry I'm finding it difficult to find sources myself , Thank you very much for the answer by the way
Comment: and of course the model of necessity only applies at long distances from the edges of any volume, so that collisions with the container don't influence the observations.
Answer: Treating something as a random variable is a tool that's used to predict the behavior of a large number of particles in bulk, when it would be practically impossible (but possible in principle) to track all of the motions individually.  And the random variable model makes good predictions in these cases because statistical facts like "laws of large numbers" and "central limit theorem" mean that particles in bulk approach Gaussian distributions (or a distribution appropriate to the situation, like Maxwell velocity distribution).  Just because it is modeled well by a random variable doesn't mean the basic interactions are not fully deterministic.
For example, the motions of the lottery balls blown around by the air machine are totally deterministic, governed by the laws of Newtonian mechanics.  But in practice, we can get excellent predictions* by assuming, for all intents and purposes, the lottery numbers are chosen "at random."
Quantum mechanical processes, like whether a given particle will be measured "spin up" or "spin down" are the only events in nature that seem to be "truly random," based on our current understanding.
To your specific question, adding an electric field to a gas may allow to you predict the bulk motion in a different way than a neutral gas, but that doesn't change the basic determinism of the situation.**
*That is, numbers will appear with a frequency that matches extremely well with a random distribution.
**Caveat: since gas molecules are quantum mechanical objects, one could debate whether their collisions and interactions should be considered "truly random" in the same way as spin measurements or wavefunction collapse.  It gets at the heart of the question "where does QM end and continuum classical mechanics begin?"
Comment: A chaotic system is not the same as an undeterministic system. A turbulent flow is completely predictable *in principle,* if we have fine enough spatial and temporal resolution to account for all the flow structure. The turbulent mixing of the lottery balls is unpredictable *in practice* because of its complexity, and we don't have the computation power to model it at fine enough resolution. In contrast, a spin up/spin down measurement of a single electron is incredibly simple, but the result is unpredictable in advance because of true randomness.
Comment: "For example, the motions of the lottery balls blown around by the air machine are totally deterministic, governed by the laws of Newtonian mechanics." Along the lines of your caveat, I was wondering whether it is truly the case that such systems are truly deterministic.  In reality, all measurements have error and we use statistics to work around that.  We say it's due to the fact there many factors that aren't known, but is that provable?  Why wouldn't quantum effects e.g.: at surface when balls collide create small scale randomness that makes the system non-deterministic?
Comment: I suppose to avoid potential confusion, instead of saying "we can get excellent predictions" (referring to lottery numbers), you might say random numbers form a good/sufficient statistical model of a lottery machine. There is no method to predict the actual values of uniformly random numbers (I know that you know this but others reading your answer might do a double take)
Comment: Jimmy, I'm not aware of any research that has identified sources of QM randomness in Newtonian macroscopic systems, but that's not to say it doesn't exist.  But it is the same as when we flip a coin 1000 times.  In each event, if given the initial conditions (geometry, rotation speed, distance to the ground, elastic properties of the ground and coin, etc) we can predict with 100% certainty that it will be heads (or tails, as the case may be).  But those initial conditions vary in a way that's practically unknowable, and so the outcome *imitates* a random variable to a very good approximation.
Comment: The lottery ball example seems a poor fit. Blown air flows turbulently (chaotically) introducing what is in principle and practice unpredictable behavior.
Answer: Random can mean many different things. Wiener process, already mentioned by @gandalf61 is a specific type of a random process, which assumes the fluctuations to be white noise, that is Gaussian noise that have the same intensity on all frequencies (which also means that it has zero correlation time.) This is a model, since any real physical noise has a finite correlation length, cannot have the same energy at all frequencies, and may deviate from a Gaussian distribution.
Whenever studying a specific phenomenon, we have to evaluate, whether this model is applicable or not. The details of interactions, discussed in the OP, influence the correlation time and limit the applicability of the model to experiments where the characteristic length scales are longer than these times. However the presence of this or that interaction does not automatically mean that the model is not applicable. Every experiment is characterized by an averaging time, since no measurement is instantaneous, thus, the collisions happening on scales shorter than this averaging time can be considered as delta-correlated.
Finally, I could like to warn against claims like
"then in this model the electrostatic force creates the "path" for the gases and this can be predicted with the net electrostatic force on the molecule right ?" (emphasis mine.) The unpredictability of molecular motion is the basis of statistical physics - it is not at all clear that the behavior of systems with $N_A\sim10^{24}$ is more degrees of freedom is predictable even in principle, see, e.g., Is limited computational capacity a fundamental obstacle?

Is Brownian motion truly random?


Man pages for Git Bash on Windows 7

Question: I am using Git bash on Windows 7. It provides me with a way to use most of the commands that I used to use on the bash shell on my Ubuntu machine. But the man and the info commands do not work. Is there a way to get these (incredible) documentation commands working on the Git bash shell on windows?
Answer: I have stitched together some of the other answers to get a man command you can use like you would natively. Just stick the following in your .bashrc, and either source it, or re-open your terminal.
function man {
    local section=all
    if [[ "$1" =~ ^[0-9]+$ ]]; then section="$1"; shift; fi
    local doc="$(curl -v --silent --data-urlencode topic="$@" --data-urlencode section="$section" http://man.he.net/ 2>&1)"
    local ok=$?
    local pre="$(printf '%s' "$doc" | sed -ne "/
/,/<\/PRE>/ { /
/ { n; b; }; p }")"
    [[ $ok -eq 0 && -n "$pre" ]] && printf '%s' "$pre" | less || printf 'Got nothing.\n' >&2
    return $ok
}

It also supports requesting particular man sections, for example man 3 printf for the system call.
Weaknesses: The source (man.he.net) isn't exactly a RESTful API, and it returns 200 even when nothing is found, so it's hard to give accurate error messages. Instead, this just prints "Got nothing", no matter what the problem was. This can probably be improved. Also, the resulting page contains html entities, such as < instead of <, which makes some usage strings ugly.
Comment: Best answer.  Thank you!  It works.
Answer: You can get man pages working on Git's bash environment, but it's probably more convenient to consider other alternatives that take less work.
I also don't have much rep on SuperUser, so I'm sad to say I can't really give all the links I need to in the response. I re-posted my response on Tumblr.
In summary:

Git's bash is a part of the msysGit project.
msysGit is a fork of the MinGW and MSYS project
You'll need either msysGit or MinGW to install MinGW-get
You'll need MinGW-get to install Groff
You'll need Groff to run these scripts to give you a man command from within the msys bash shell
With those scripts in place, you can read man pages. You'll just need to download them to the path you've indicated in the scripts.

Good luck.
Comment: You can install man with `MinGW-get install msys-man`. Man is also available as a windows binary: https://sourceforge.net/projects/ezwinports/files/ (found via the FAQ: http://www.mingw.org/wiki/FAQ#toc10). That page also has groff. Either would probably run faster than those scripts.
Comment: @SamHasler msys-man is great. Thanks for the tip, I don't know how I missed that.
Answer: It may be a bit overkill, but you could download Cygwin which would include bash, man, and info readers like pinfo.
The cygwin installer would let you customize your install to be a pretty small subset of cygwin.
Comment: Not overkill in the slightest; it seems fairly common that someone will want a Unixy experience on Windows and install Git Bash mistakenly thinking that's the way to get one. Cygwin, meanwhile, actually provides one, probably to the maximal extent possible or very nearly so.
Answer: In addition to Sathya's answer, you could also do this in bash for Windows:
curl -v --silent "http://man.he.net/?topic=<command_name>&section=all" 2>&1 | sed -n "/
/,/<\/PRE>/p"

Just replace the <command_name> with the command you're looking for.
Example output for the command ls:

 SYNOPSIS
         ls [OPTION]... [FILE]...
DESCRIPTION
         List  information  about  the FILEs (the current directory by default).
         Sort entries alphabetically if none of -cftuvSUX nor --sort  is  speci-
         fied.
   Mandatory  arguments  to  long  options are mandatory for short options
   too.

   -a, --all
          do not ignore entries starting with .

   -A, --almost-all
          do not list implied . and ..

   --author
          with -l, print the author of each file

   -b, --escape
          print C-style escapes for nongraphic characters

   --block-size=SIZE
          scale   sizes   by   SIZE   before   printing    them.     E.g.,
          `--block-size=M'  prints sizes in units of 1,048,576 bytes.  See
          SIZE format below.

   -B, --ignore-backups
          do not list implied entries ending with ~

   -c     with -lt: sort by, and show, ctime (time of last modification of
          file  status  information)  with -l: show ctime and sort by name
          otherwise: sort by ctime, newest first

   -C     list entries by columns

   --color[=WHEN]
          colorize the output.   WHEN  defaults  to  `always'  or  can  be
          `never' or `auto'.  More info below

   -d, --directory
          list  directory entries instead of contents, and do not derefer-
          ence symbolic links

   -D, --dired
          generate output designed for Emacs' dired mode

   -f     do not sort, enable -aU, disable -ls --color

   -F, --classify
          append indicator (one of */=>@|) to entries

   --group-directories-first
          group directories before files.

          augment  with  a  --sort option, but any use of --sort=none (-U)
          disables grouping

   -G, --no-group
          in a long listing, don't print group names

   -h, --human-readable
          with -l, print sizes in human readable format (e.g., 1K 234M 2G)

   --si   likewise, but use powers of 1000 not 1024

   -H, --dereference-command-line
          follow symbolic links listed on the command line

   --dereference-command-line-symlink-to-dir
          follow each command line symbolic link that points to  a  direc-
          tory

   --hide=PATTERN
          do  not  list implied entries matching shell PATTERN (overridden
          by -a or -A)

   --indicator-style=WORD
          append indicator with style WORD to entry names: none (default),
          slash (-p), file-type (--file-type), classify (-F)

   -i, --inode
          print the index number of each file

   -I, --ignore=PATTERN
          do not list implied entries matching shell PATTERN

   -k     like --block-size=1K

   -l     use a long listing format

   -L, --dereference
          when showing file information for a symbolic link, show informa-
          tion for the file the link references rather than for  the  link
          itself

   -m     fill width with a comma separated list of entries

   -n, --numeric-uid-gid
          like -l, but list numeric user and group IDs

   -N, --literal
          print  raw entry names (don't treat e.g. control characters spe-
          cially)

   -o     like -l, but do not list group information
          enclose entry names in double quotes

   --quoting-style=WORD
          use  quoting style WORD for entry names: literal, locale, shell,
          shell-always, c, escape

   -r, --reverse
          reverse order while sorting

   -R, --recursive
          list subdirectories recursively

   -s, --size
          print the allocated size of each file, in blocks

   -S     sort by file size

   --sort=WORD
          sort by WORD instead of name: none -U, extension  -X,  size  -S,
          time -t, version -v

   --time=WORD
          with  -l,  show time as WORD instead of modification time: atime
          -u, access -u, use -u, ctime -c, or  status  -c;  use  specified
          time as sort key if --sort=time

   --time-style=STYLE
          with  -l, show times using style STYLE: full-iso, long-iso, iso,
          locale, +FORMAT.  FORMAT is interpreted like `date';  if  FORMAT
          is  FORMAT1<newline>FORMAT2, FORMAT1 applies to non-recent files
          and FORMAT2 to recent files; if STYLE is prefixed with `posix-',
          STYLE takes effect only outside the POSIX locale

   -t     sort by modification time, newest first

   -T, --tabsize=COLS
          assume tab stops at each COLS instead of 8

   -u     with  -lt:  sort  by, and show, access time with -l: show access
          time and sort by name otherwise: sort by access time

   -U     do not sort; list entries in directory order

   -v     natural sort of (version) numbers within text

   -w, --width=COLS
          assume screen width instead of current value

   -x     list entries by lines instead of by columns

   -X     sort alphabetically by entry extension

   -Z, --context
          print any SELinux security context of each file

   Using color to distinguish file types is disabled both by  default  and
   with  --color=never.  With --color=auto, ls emits color codes only when
   standard output is connected to a terminal.  The LS_COLORS  environment
   variable can change the settings.  Use the dircolors command to set it.

Exit status:
         0      if OK,
   1      if minor problems (e.g., cannot access subdirectory),

   2      if serious trouble (e.g., cannot access command-line argument).

AUTHOR
         Written by Richard M. Stallman and David MacKenzie.
REPORTING BUGS
         Report ls bugs to firstname.lastname@example.com
         GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
         General help using GNU software: <http://www.gnu.org/gethelp/>
         Report ls translation bugs to <http://translationproject.org/team/>
COPYRIGHT
         Copyright  (C) 2011 Free Software Foundation, Inc.  License GPLv3+: GNU
         GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
         This is free software: you are free  to  change  and  redistribute  it.
         There is NO WARRANTY, to the extent permitted by law.
SEE ALSO
         The  full  documentation  for ls is maintained as a Texinfo manual.  If
         the info and ls programs are properly installed at your site, the  com-
         mand
          info coreutils 'ls invocation'

   should give you access to the complete manual.

GNU coreutils 8.12.197-032bb    September 2011
  LS(1)

Answer: You could use the online documentation.
Linux man pages online & GNU Info Pages
Comment: Doesn't answer the OP's question; he wants these commands to work in the shell.
Comment: @Prasanth perhaps you can do a wget  & then grep it.
Comment: are there any programs that will connect to these web pages from the command line and display the result? so that I can still type info grep on the shell and get the results there?
Comment: or he could do this `curl "http://man.he.net/?topic=&section=all"`. replace the `` with the command you're looking for
Answer: The answer, from this question, might be helpful:
Gives you info for the command right in the bash window.

Git command Quick Reference
git [command] -help

Opens the online info for the command in your browser.

Git command Manual Pages
git help [command]
git [command] --help

Comment: In the future it will be expected you cite and quote the relevant information when you provide a link.  You should also learn how to properly format your answers.
Comment: This appears to only be for Git commands.  These are not necessarily the same as their non-git counterparts.  For instance `git grep` does not support the `-R` option. https://git-scm.com/docs/git#_git_commands
Answer: If anyone else is trying to get man to work on Windows and is using Msys2, here is what I found:
I got very close by using the answer above which says to install groff (available via pacman) and then use the script here, which has at its core the call to groff -Tascii -mandoc -P-c.
But I could not get it to work on my man pages (found in /usr/share/man) unless I uncompressed the gz files first!
This was not an acceptable solution, so I looked further and found that by running
pacman -Ss -man

that there are three packages (currently) that have the prefix of "man-".  (see them here).
I tried the one called man-db, it works, and now I have ability to run man in the regular expected fashion.
Comment: Today I am able to simply run `pacman -S man` and install proceeds as expected
Answer: Add it to the end of .bashrc
C:\Users\<Username>\.bashrc
function man() {
    VAR1="http://man.he.net/?topic="
    VAR2=$1
    VAR3="&section=all"
    VAR4="$VAR1$VAR2$VAR3"
    curl -v --silent "$VAR4" 2>&1 | sed -n "/
/,/<\/PRE>/p"
}

Add it to the end of .bash_profile
C:\Users\<Username>\.bash_profile
# Read .bashrc
source ~/.bashrc

Restart terminal.
man find will return the manual pages for find.

Here is a version for really short answer:
function man-short() {
    $1 --help
}

Man pages for Git Bash on Windows 7


Quotation ascribed to Benjamin Franklin, "We are all born ignorant, but one must work hard to remain stupid."

Question: There is a cottage industry in the United States of manufacturing quotations and ascribing them to the American Founding Fathers.  A recent one, "We are all born ignorant, but one must work hard to remain stupid," ascribed to Benjamin Franklin.  The language and structure just don't sound like Franklin.  The parsing of the difference between stupid and ignorant seems to have arisen after Franklin's death based on an N-gram comparison.  Unfortunately, I don't have OED access to make that comparison in a more authoritative manner.  The question is, does the quotation (as edited) sound as if it might have come out of the 18th century?
Comment: This question appears to be off-topic because it is about the proper attribution of a quotation.
Comment: I very much like this question. I hope someone with better  google-fu than I have answers it.
Comment: I retracted that. It's not clear what's being asked. Apologies.
Comment: Like you I'm quite suspicious of this. It doesn't read much like Franklin. Unfortunately, I don't see any words or phrases distinctive enough to grab hold of with ngrams. I know if I were faking an attribution for it, I would have picked Twain or Will Rodgers. It reads much more like a spoken comedy punchline, which both of them engaged in.
Comment: My quick Google reenforced what folks said below -- no solid references linking the quote to Franklin, and several sites (fairly consistent with each other) which questioned the authenticity and traced the quote back to 1995 or so.
Answer: What Franklin didn't say
Like FumbleFingers, I can't find any attribution of the quoted language to Franklin before about the turn of the twenty-first century. (A Google Books search finds one instance from the year 2000, in 2001 Librarian's Engagement Calendar and Almanac.) On the other hand I did find the following quotation attributed to another popular source of folk wisdom—namely, "Chinese Proverb"—in Mary Cole, The Circles of Life (2008):

He who asks a question is a fool for five minutes; he who does not ask a question is a fool forever. We are all born ignorant, but to stay ignorant is a choice, without some form of education you are lost. —(Chinese Proverb)

And another folk favorite, Mark Twain, receives credit for this version of the saying, from Mohammad Mujeeb-ur-Rahman, The Betrayal of Intellect in Higher Education (1997):

Man is only born ignorant. It takes four years of college to make him stupid. —Mark Twain

The closest wording I've seen to the supposed Franklin quote before 2000 is from Earl Nightingale, This Is Earl Nightingale (1969) [combined snippets]:

Every human being has to be born ignorant and, for a time, live in ignorance. But if he remains ignorant that is his own fault. The fight against ignorance waged by everyone during his or her lifetime must be an individual, personal thing.

Unlike the other three authors I've cited so far, Nightingale takes full credit for his statement.
To me, the strongest argument against Franklin's responsibility for the cited quotation has two parts: (1) the quotation doesn't show up in the Google Books database until around 2000; and (2) when it does show up, no one cites the source in Franklin's work for it.
In the 520 Google Books search matches I looked at for the phrase "born ignorant," I found multiple references to (and some paraphrases of) relevant quotations from St. Augustine, Giordano Bruno, John Knox, Samuel von Pufendorf, Baruch (Benedict) Spinoza, John Locke, Thomas Halyburton, Isaac Watts, Claude Helvétius, Mary Wollstonecraft, Laurence Stern, Henry Ward Beecher, Thomas Hood, Edward Bulwer Lytton, Emmanuel Swedenborg, and Bertrand Russell—and all of them ultimately tied the quoted language to a particular work containing the phrase. The Franklin quote was the lone exception: No one offers any clear source in his work for it. I have no doubt that the attribution of this wording to Franklin is spurious.

What Franklin probably did say
Having rejected the attribution of the quotation cited by the OP to Franklin, I note that one source, Poor Richard's Almanac (1914), which consists of "Selections from the apothegms and proverbs" of Franklin, offers this otherwise unsourced saying:

Being ignorant is not so much a shame, as being unwilling to learn.

This quotation has a trail that goes back to Benjamin Franklin, Autobiography. Poor Richard. Letters. (1899), which lists it (with the word Shame capitalized) in a section titled "Sayings of Poor Richard, Selected from Dr. Benjamin Franklin's "Poor Richard's Almanack, 1733–1758." Even better, Bob Blaisdell, The Dover Anthology of American Literature, volume 1 (2014), assigns this Franklin quotation to the year 1755. That's the way a legitimate quotation tends to behave.

Where Franklin may have gotten the idea for what he said
A possible inspiration for the quotation (noted by Henry in his answer) is Claude Adrien Helvétius, De l'Esprit [On Mind] (1758). A translation of this book by W. Hooper, M.D., appeared in 1810 under the title A Treatise on Man; His Intellectual Faculties and His Education, with the following relevant passage:

OF FALSE SCIENCE, OR ACQUIRED IGNORANCE
Man is born ignorant ; he is not born a fool ; and it is not even without labour that he is made one. To be such, and to be able to extinguish in himself his natural lights, art and method must be used ; instruction must heap on him error upon error ; more he reads, the more numerous must be the prejudices he contracts.

A 1777 edition of Hooper's translation of the book replaces "fool" with "sot" and concludes the quoted paragraph with "he must have multiplied his prejudices by a multitude of lectures," but otherwise the versions of the paragraph are identical.
De l'Esprit may or may not be the source of the quotation attributed to Benjamin Franklin. It seems to be even more in tune with a quotation from Bertrand Russell (cited in FumbleFingers's answer): "Men are born ignorant, not stupid. They are made stupid by education." In fact, Russell's observation occurs—in his A History of Western Philosophy (1946)—in the context of a discussion of Helvétius:

Following Locke's doctrine that the mind is a tabula rasa, Helvetius considered the differences between individuals entirely due to differences of education: in every individual, his talents and his virtues are the effect of his instruction. Genius, he maintains, is often due to chance: if Shakespeare had not been caught poaching, he would have been a wool merchant. His interest in legislation comes from the doctrine that the principle instructors of adolescence are the forms of government and the consequent manners and customs. Men are born ignorant, not stupid. They are made stupid by education.

Helvétius in turn may have been influenced by Baruch Spinoza's Tractatus theologico-politicus (1670):

The natural right of every man therefore is determined by appetite and power, not by sound reason. For all are not constituted by nature to act according to the rules of reason. On the contrary, all are born ignorant of everything; and before they can know the true rule of life, and acquire virtuous habits, a great part of their lives must already have passed.

Benjamin Franklin was 52 when Helvétius published De l'Esprit, and it would be very surprising if he never read it, especially given that its "atheistic, utilitarian and egalitarian" ideas caused considerable scandal at the time it appeared (according to the Wikipedia article on Helvétius). Of course, if Franklin published his maxim about ignorance and shame in 1755 (as the Dover Anthology of American Literature asserts), he beat Helvétius to the punch by three years. In that case, Franklin's likeliest inspiration would have been John Locke, Of the Conduct of the Understanding (1706), who echoes Spinoza in his assessment of the human mind:

We are born ignorant of everything. The superficies of things that surround them make impressions on the negligent, but nobody penetrates into the inside without labour, attention, and industry.

If this is the correct chronology, then Franklin, not Helvétius, was the first to invert the argument of Spinoza and Locke that rising above one's native ignorance requires considerable effort (and presumably, education).
Comment: A fantastic answer! Worth far more than my sorry bounty.
Answer: "Man is born ignorant; he is not born a fool; and it is not even without labour that he is made one....
~  Claude Adrien Helvétius (1715-1771) On Man
From Man a Revelation of God by George Everett Ackerman, Phillips & Hunt, 1888
Comment: Note that one recent collection that reproduces the Franklin quotation (_The Dover Anthology of American Literature_ [2014]) specifies that Franklin's apothegm appeared in the 1755 _Poor Richard's Almanack_, which would be three years before Helvetius published _De l'Esprit_.
Comment: Bravo! I admire your google-fu. I added 'proof' (though I didn't doubt you). Hope that's OK.
Comment: Franklin will have read this in the original French, not in the 1810 translation. It would be interesting to have the original to regard as well.
Answer: Given this citation from 1724...

To be Stupid and Ignorant is seldom the Character of a Thief.
Robberies on the High-way and other bold Crimes are generally perpetrated by Rogues of Spirit and a Genius, and Villains of any Fame are commonly subtle cunning Fellows...

...I think we can safely say OP's cited "Benjamin Franklin" quote would have been idiomatically perfectly credible in the 1700s. Whether it actually was from Franklin himself is another matter which I can't answer, but I will just note that all sorts of things get wrongly attributed to our favourite "epigrammists" such as Ben Franklin, Mark Twain, Winston Churchill, etc.

Having said that, I rather doubt Franklin did come up with this one. Firstly, it doesn't look to me like the type of thing he would say. Secondly, the earliest written instance of it I can find is 1999.
But mainly, I suspect it's a just mangled version of what Bertrand Russell (1872-1970) said...

Men are born ignorant, not stupid. They are made stupid by education.
Answer: Benjamin Franklin in famously xenophobic speech used after 1747, uses ignorant and stupid in the same sentence regarding German immigrants. Obviously a pattern he employed, not clear why the controversy.
http://www.dialoginternational.com/dialog_international/2008/02/ben-franklin-on.html


How can someone accept or deny a smart contract in Ethereum?

Question: Let's say peer A has deployed some contract and releases the ABI to peer B to be the part of the network as peer. If B wants to modify the contract or B is not agree with the contract then what he can do? Can he deny the contract some way in Ethereum so that peer A can be updated about that decision?
Comment: This question is complex, because I think you are a bit confused about smart contracts and the transactions and how it works.
Answer: A "contract" in the real world is usually between multiple people, but in the Ethereum blockchain, a (smart) contract is published by one account, so at the most simple level is only from one person.
A simple contract in Ethereum only proves that Person A said something, not necessarily that the thing is true (If person B doesn't think it's true, there's nothing they can do to prevent A saying it).
But contracts in Ethereum can save data, and therefore can have different states. In the real world, a contract is drafted ("new" state), and if you agree, you sign it ("gathering signatures"), and once everyone has signed, it's active, and it may have clauses where it can be cancelled/voided. A contract in Ethereum can do the same, keeping track of who has signed a contract, agreeing to it's content, and whether it's cancelled or not. In that case, B can just not sign the contract, and it never becomes active. But the contract would have to be written to have that flexibility/logic built-in.
If there's a collaboration between two parties, ideally they'd communicate (not through Ethereum) about what the contract should be, and perhaps test it on the testnet before deploying it to the main blockchain. If one of the parties thinks there's something wrong with the contract once it's deployed, there is no way to remove a contract once it's deployed, unless the contract itself has logic that can do it (referred to as a suicide condition).
Answer: There's definitely a misconception in this question about how a contract gets deployed.
The nodes in the system (your 'A' and 'B') do not decide if they 'like' or 'agree' with a contract. Someone deploys the contract, and as long as the deploying address has enough gas to pay for the deployment, the contract gets added to the blockchain. From then on, if a transaction is sent against that contract, every node runs that transaction.
Nor can B 'modify the contract' or 'not agree' with it. Either the deploying address has enough gas or it doesn't. If it does, the contract is deployed. Subsequent transactions sent to that contract are processed. The nodes do not discriminate at all about (nor do they even know) what the contracts do.
Comment: Let's say Peer A created a contract and deployed it. Peer B will get the contract ABI from A. But ideally peer B are not able to see real code or implementation. Without seeing it how he will be going to accept this contract.Please clarify......


Is it wrong to associate many accounts for the 100 bonus?

Question: I have a few associated accounts. When I go on another Stack Exchange site, I'm tempted to associate it for the 100 point bonus, even if I'm only reading and not posting. Is this greedy? Would it be unethical to associate with sites I don't even read for the 100 point bonus?
Comment: possible duplicate of [Q&A sites wrongfully discourage people from thinking for themselves with respect to Q&A sites](http://meta.stackexchange.com/questions/58931/qa-sites-wrongfully-discourage-people-from-thinking-for-themselves-with-respect)
Answer: You're supposed to associate your accounts. That's to help the system much more than being some sort of reputation-grabbing, free give-away for the greedy.
Remember, reputation is a rough measurement of your experience with the system. The +100-rep association bonus is to give you a quick boost for the experience you have already EARNED on other systems. That bit of reputation empowers you with some of the most basic (and sorely needed) resources needed to be spread across the sites.
There is absolutely nothing unethical or greedy about it.
Answer: It's not greedy. It isn't like there's a limited amount of Rep to go around. The whole point of the bonus is so that users who have shown that they have experience with and have proven they can be trusted on one SE site are allowed to have the basic privileges on another.
Answer: What difference does it make? You don't get any more points on the sites you're already using (the bonus is one-time per site), just the new one, and having points is irrelevant if you don't use them.
Answer: By getting 200 points on site A you've demonstrated you know how to ask and answer questions, vote, comment and otherwise participate in the site.
By giving you a 100 point bonus the system is acknowledging that level of expertise and allowing you to do it from "day one" on site B.
By having more people who can do these things and have demonstrated they know the way Stack Exchange operates site B will be a better place and will (hopefully) be more likely to succeed.
Answer: Why should it be unethical. You can add the site, follow it and decide it is not for you.
 Or you can save it for later.
Comment: It just feels greedy... But I'm guessing the 100 points are meant to encourage it.


How to play the intro of Legends of Andor with two players?

Question: I just got Legends of Andor and was trying to play the intro with two players. Having only two heroes, it seems the objectives cannot be reached in one day. Is Andor meant to be played with all heroes always, like e.g. In Mice and Mystics? I couldn't find any hints so far in the manual.
Answer: It is possible to reach all the objectives with just two players, and that is the way that it is designed.  Unlike Mice and Mystics, Legends of Andor has much more of a puzzle feel to it and you need to plan carefully in order to accomplish things within the time limits.  Keep in mind that you can move through the castle, that is one thing that often makes people think it takes longer than it really does.
Comment: Yes, the game seems much more strategic to me than M&M. However, I cannot figure out how to achieve the very first goals in one day on the A1, the very first card. Movements alone take more than 7 hours.
Comment: Which characters were you using?  The exact moves will vary based on that.  I can try to figure them out for you if you want, though I don't actually own the game.
Answer: I advise you to play with 2 characters each, you only have 14 hours to spend with 2 players on a given day vs. 28 with 4 players, so you have way more time with 4.
Answer: Apologies if I've used any wrong terms. I've only got the German version and translated names and things myself. Feel free to fix them if they don't match the English version of the game.
The intro legend is definitely possible with any pair of heros. With some combinations it's definitely not trivial, but I quite liked that about it, that it immediately drives home the point that this game has a strong puzzle component, where you need to plan your collaborative actions to achieve the goals with the limited resources you have.
Provided I didn't make any mistakes, below are "walkthroughs" for all 6 possible pairs of heros for the very first legend card on the intro legend. The trickiest one is probably the dwarf and ranger combination. Also for most of these, the solutions are not unique (maybe for all of them).
The number in parentheses represents the number of hours remaining for that particular hero.
Dwarf & Warrior:

Dwarf → 13 (fog; 3)
Warrior → 5 (well; 4)
Dwarf → 17 (coins; 2)
Warrior passes (3)
Dwarf → 18 (merchant; 3)
Warrior → 0 (castle; 1)

Dwarf & Ranger:

Dwarf → 17 (coins; 3)
Ranger → 13 (fog; 4)
Dwarf → 18 (merchant; 2)
Ranger → 5 (well; 1). Note that this path goes through the castle.
Dwarf passes (1)
Ranger → 0 (castle; 0)

Dwarf & Mage:

Dwarf → 17 (coins; 3)
Mage → 11 (fog; 5)
Dwarf → 18 (merchant; 2)
Mage → 5 (well; 3). Note that this path goes through the castle.
Dwarf passes (1)
Mage → 0 (castle; 2)

Warrior & Ranger:

Warrior → 5 (well; 4)
Ranger → 13 (fog; 4)
Warrior passes (3)
Ranger → 17 (coins; 3)
Warrior passes (2)
Ranger → 18 (merchant; 2)
Warrior → 0 (castle; 1)

Warrior & Mage:

Warrior → 17 (coins; 3)
Mage → 11 (fog; 5)
Warrior → 18 (merchant; 2)
Mage → 5 (well; 3). Note that this path goes through the castle.
Warrior passes (1)
Mage → 0 (castle; 2)

Ranger & Mage:

Ranger → 17 (coins; 4)
Mage → 11 (fog; 5)
Ranger → 18 (merchant; 3)
Mage → 5 (well; 3). Note that this path goes through the castle.
Ranger passes (2)
Mage → 0 (castle; 2)

Of course, this is only the first part of the intro legend, and there's quite a lot more to it. However, I can't really give a detailed walkthrough for this, because the actual outcome depends partly on luck and you'll have to improvise a bit. I suppose, if you have really bad luck it might be impossible to solve it, but we did manage to get through on the first try. It definitely required some thinking though, and the game is supposed to be challenging.
I'm sure there's other ways to solve it, but if you want a hint, here's a neat trick which helped us make it through to the end and which probably applies to most if not all pairs of heros:

 Once we got the final (non-ending) legend card on "day" H, we had one character pick up the scroll and the other move to a field around 36. So on the next turn we could do a sort of torch relay, where the first character brings the scroll to 36, hands it off to the other one who can then use their own moves to get to 71. There we waited for two turns to let the Skral pass and then the goal can easily be reached within one turn.

 One thing worth noting is that we really needed to use up the monster slots in the top left corner. Every killed monster is "worth" a day, and you'll easily reach day N if you try to kill them all. Note that the monsters that spawn on step H can't really reach the castle at all (the same was true of a few other monsters in our case). Their only point is to create a bottleneck near field 39 on the rush to the goal. Every monster that you allow to reach the castle is one more turn you've got to reach the goal, so it's definitely a trade-off worth considering (and probably necessary to some degree).


Find the range of the function $y = \sqrt{7 - x^2}$?

Question: I tried to find the range of the following function : $$y=\sqrt{7-x^2}$$
I found the domain which is: $$ y \in (-\sqrt7,\sqrt7) $$
and then I tried to find the range of the function with the method of finding the domain of its inverse function. So : $$y=\sqrt{7-x^2} \Rightarrow $$ $$y^2=7-x^2\Rightarrow$$ $$x^2=7-y^2\Rightarrow$$
$$x=\sqrt{7-y^2} $$
Domain of which is
$$ x \in (-\sqrt7,\sqrt7) $$ But the correct solution is: $$ x \in (0,\sqrt7) $$
Can someone explain where is the mistake?
Comment: The notation $\sqrt{x}$ means the [principal (nonegative) square root of $x$](https://math.stackexchange.com/questions/1033604/why-is-sqrtx-a-function/1033616#1033616).
Answer: Since domain of $y$ is $x \in [-\sqrt7 , \sqrt7]$, then range of $y$ is $y \in [0,\sqrt7]$.
Answer: Since $\sqrt{7-x^2}$ can never be negative this excludes all the values $(-\sqrt{7},0)$.
Answer: I think you have displaced the concept of domain and range. The domain actually constrains the independent variable which is $x$ here. So the domain is $$x\in[-\sqrt 7,\sqrt 7]$$and the range consecutively becomes $$y\in[0,\sqrt 7]$$
Answer: First, a tidbit about notation. The domain variable is $x,$ not $y,$ and vice versa. As for the range, recall that if $$y=\sqrt{7-x^2},$$ then since RHS is never negative, it follows that $$0\le y.$$ Combine this with the your calculation that $|y|\le\sqrt 7,$ and you're done.
Answer: The image of the function described by $y = \sqrt{7 - x^{2}}$ is the upper semicircle centered at the origin with radius $\sqrt{7}$. Thus its range is given by the set $[0,\sqrt{7}]$.
Answer: The implicit domain of the function $y = \sqrt{7 - x^2}$ is the set of all real numbers $x$ such that $7 - x^2 \geq 0$.
\begin{align*}
7 - x^2 & \geq 0\\
7 & \geq x^2\\
\sqrt{7} & \geq |x|
\end{align*}
Hence, $-\sqrt{7} \leq x \leq 7$, so the domain of the function is $[-\sqrt{7}, \sqrt{7}]$.  Notice that the endpoints are included.
The notation $y = \sqrt{x}$ denotes the principal (nonnegative) square root of $x$.
Therefore, $y = \sqrt{7 - x^2} \geq 0$ for each $x$ in its domain.  In particular, equality holds if $x = \pm \sqrt{7}$.  Moreover, $y = \sqrt{7 - x^2}$ is at most $\sqrt{7}$, which occurs when $x = 0$. Since $y = \sqrt{7 - x^2}$ is continuous on its domain, $y$ assumes every value in the closed interval $[0, \sqrt{7}]$ by the Intermediate Value Theorem. Hence, the range of the function is $[0, \sqrt{7}]$. Again, notice that the endpoints are included.


Is there any calcium carbonate analogue drawing carbon from dry air?

Question: Is there a nonliving (wood does not count) substance or process that accretes a solid material by withdrawing carbon from the air, in a manner analogous to calcium carbonate being accreted from seawater in biorock/seacrete?
Comment: The alteration of concrete is an example.
Answer: There is no carbon in the air. Air contains some carbon dioxide, but carbon is not carbon dioxide. Carbon is a solid stuff. Carbon dioxide is a gas. Carbon dioxide can be removed from air by bubbling in a suspension of (insoluble) calcium carbonate in water. The reaction occurs according to the equation :  $$\ce{CaCO3  +  CO2  +  H2O  ->  Ca^{2+} + 2 HCO3^-}$$


Transaction can not be found

Question: Sender shows bitcoin being sent be it can not be found when I look for it in blockchain explorer nor can the send produce a transaction number
Answer: When using bitcoin, you don't have to trust anyone to tell you if you received a transaction, you can verify it for yourself.
To do so, you can run a bitcoin 'full node' (such as the bitcoin core software), and then query the node to find the transaction in question.
Failing that, you can check to see if your wallet software has received a new transaction.†
Failing that, you can check an online block explorer service to see if the transaction exists.†
If any one of these methods doesn't reveal the transaction in question (and your software is otherwise all properly synced with the network), then there is no reason to believe the person who said they sent you funds actually did. They may have encountered a software issue, or they may be attempting to defraud you.
†both of these methods involve trusting someone else to do the validation steps for you, but it is perhaps better to trust a third party, that has little economic incentive to defraud you

Transaction can not be found


Does it make sense to apply for an internship in a bigger, renowned company if I am already employed as junior in a smaller company?

Question: I am finishing my master degree and currently employed in my area (Machine learning) in a startup. I know about open positions for an internship in the area in NVIDIA. I would really like to work there, I think it would a great place to work and to grow in my career. However I wonder if it would make sense to apply for an internship there if I am already employed. On one side I feel that making the internship there would pay off in the future by the growth opportunities and salary. However this would mean a step back in my career. Does it make sense? Is a renowned company worth enough working there as intern?
Of course it would be great to join there for a full time employment instead, but it seems to me much harder than to join as intern. Am I wrong?
Comment: I think this boils down to what you want in the end. It's your career, your money, your experience. Changing companies is something that could make sense, but the question is if that's what you want right now?
Comment: I think doing an internship while being employed would raise questions or eyebrows in an interview since it doesn't make a lot of practical sense and call your devotions into questions.
Comment: How long have you been employed in your current role?
Comment: @sf02 about 8 months
Comment: @JoeStrazzere I wanted to work there because it seems to me that it would offer the best growth opportunities and best salary in the long term. Also because Nvidia is a name recognizade everywhere, while my current employer is not. However I dont know if these things are really true or that relevant as it seems to me
Answer: "Company renown" and company size are... not all that.  Going from "I'm getting paid a reasonable salary" to "I'm working for free" is generally a poor choice.  If you signal that you're willing to take that much of a hit to your income in order to work for them, they will exploit that, and the salary they offer will be adjusted accordingly.
If your current job is giving you reasonable income and opportunities for growth, then stay where you are.  If it's not, then you should be looking for positions elsewhere... but going from "masters degree with pertinent work experience" to "intern" is basically not going to be worth it ever.  The fact that you're hanging an "exploit me" sign around your own neck would be too much of an issue all by itself.
Comment: I believe many companies (particularly bigger ones) will pay their interns. In countries like Canada, companies are actually legally required to pay their interns ([HootSuite is an example](https://globalnews.ca/news/489166/hootsuite-gives-interns-back-pay-ends-controversial-practice-of-unpaid-internships/)). The junior role at the smaller company might not pay well, so going to work as an intern at a bigger company might not be that much of a step down. Having said that, I do believe OP should be looking for positions at or above his current level (and not internships).
Comment: @zmike Interns are sometimes paid.  They're basically never paid as much as actual workers in the field.  In my experience, salary is not particularly strongly influenced by size of company overall, though it's possible that this *particular* small company does not pay well.
Comment: They also almost always don't have the same employee rights.  They are certainly, if they are paid, will be the first to go when a budget hit comes.  They are also potentially not permanent hires.
Comment: @BenBarden yes... you have a great point that i haven't thought about. And the internship position in question is paid, but it would be less than what I get indeed.
Answer: No, internships are for students to bridge the education-to-work-environment gap, and you're already working in the field.
Additionally, your experience at a startup is far, far more valuable since you are potentially executing a larger range of activities with smaller teams to meet your goals. Moving to a larger company means many of those related roles are filled by entire teams — e.g. the UI, marketing, UX design are handled by an entirely different groups and you rarely interact.


A way to view recent played with?

Question: Is there a way to view players i recently played with except the steam overlay? I know there was a year ago in the log files but they fixed it by now. I tried to use the steam webinterface but i won´t show recent players i played in rocket league. It only shows up a list in the steam overlay. Is there a way to extract those players from a file or sth ? Thanks in advance
Comment: The overlay is the only method I'm aware of, unfortunately
Comment: Where so I find this in the overlay? I have been looking for a while but can't seem to find it...
Answer: I don't see any other way than using the steam overlay, except you can write yourself some basic scripts in like java or something like that. But if you really want to have those player names in a list automatically and you have some basic programming understanding, you could write yourself a script which fetches the information from this URL (http://steamcommunity.com/id//friends/coplay/) and then save it wherever you like. (.txt file, spreadsheet etc.) To use this link, you have to be signed into steam on your browser. Maybe this can help you!

A way to view recent played with?


major.minor.build.revision versioning style vs year.month.day.whatever versioning style

Question: Is there any reason to use one versioning style over the other for .NET assemblies????
I'd like to know if there are any advantages/disadvantages in using either style besides taste.
Answer: The advantage of time is that you get both an increasing version number and encode the timestamp.
The advantage of using more traditional numbers is that it's easier for people to understand.  We all know roughly what "v2.1" means, for example.
In general I suggest using time because the added information is useful.  The advantage of the other numbers is for marketing only, and for that you can do it anyway.
For example, why not have both, a la "v2.1.20090214."  Now you have marketing in the major.minor section and utility in the "build" section.
Comment: Note that on Win32 (and thus .NET), the version numbers have a 16-bit limit per component, so 20090214 as one component is not possible.
Comment: If you use a date as the version number, for mercies sake use YYYYMMDD format.  It is the only one that just about anybody can read unambiguously, and has the advantage of lexically sorting in the correct order.
Comment: (For the parochial among us, some countries write their dates in MM-DD-YYYY format, and most of the rest of the sane word writes them in DD-MM-YYYY or YYYY-MM-DD format.)
Answer: The advantage of using major.minor.revision scheme is semantics. There's a method to updating each of these numbers:
Major number change means that the new version is incompatible with the old one and any dependent of the prior version will require code changes to upgrade to the new package.
Minor number change means that the new version is backward compatible with the previous version but has significant enhancements over the previous version.
Revision number is updated whenever a bugfix is applied to the build such that it doesn't bring a compatibility change or introduce newer features.
While specifying dependencies, you can thus say that you depend on foo-1.0.0 - foo-1.99.999, and rest assured that you won't end up with a package upgrade that breaks your application.
If you started with a higher minor version of a dependency, say, foo-1.4.22, you should specify the dependency as foo-1.4.22 - foo-1.99.999, so that you don't end up installing a version older than 1.4.x, which might have some functionality/enhancement missing from it.
Answer: I just leave the AssemblyVersion at "1.0.*" and remove any AssemblyFileVersion.
I can then increment the Major and Minor version numbers as seems appropriate and let the default DateTime base build and revision be automatically set.
Unless you have alternative build tools controling the build and revision number according to some other scheme I can see no real advantage to setting them manually.
Comment: I'm doing exactly the same thing.
Answer: Using time/date has one more (apart from those already mentioned in other answers here) disadvantage:
if you're dev team is spread over different time zones, you'll never be sure which one of two versions build one hour apart is the newer one. Unless you also version the timezone or force the date/time to be in e.g. GMT.
Answer: I use some build scripts that update my revision based on the SVN revision. That makes it trivial to track a dll back to the source code that created it.
Time is trickier; you have to start looking in the history pane - where-as most source control tools have a "get revision " facility.
Answer: Why choose? You can use a format such as Major.Minor.YYMMDD.Revision and get the best of both worlds.
Edit
As pointed out in the comments sometimes the range of each field is restricted. In that case you can use Major.Minor.YMMDD.Revision.
Hopefully you would change minor version at least every 10 years!
Comment: please correct me if a i'm wrong, but according to MSDN at "http://msdn.microsoft.com/en-us/library/system.reflection.assemblyversionattribute.aspx" each component must be a number between 0 and 65535. YYMMDD would be too large. "Major.Minor.YYYY.MMDD" would fit but is ackward :-(
Answer: One disadvantage of date-based version numbering is the negative perception of old software.
Although, I use it anyway because it fits my projects very well.
Comment: Not always a disadvantage. That negative perception can be used to sell your new version.


Who is exempt from obtaining a Schengen visa?

Question: I am British, my husband is from El salvador. We want to visit frankfurt, madrid., crete and italy for a few days only before going to UK . Do we need any visas like a tourist visa or a schengen visa?
Comment: The alleged duplicate question concerns a Jordanian, while this one concerns a Salvadoran. El Salvador is an Annex II country, whose nationals don't need a visa for short stays in any case, and the answers to the alleged duplicate do not consider that possibility. The correct answer to this question is *no,* while the correct answer to that one is *yes.*  Voting to reopen.
Answer: Your husband is exempt from both Schengen and UK visa requirements on the virtue of being a citizen of El Salvador. In addition, he may take the EU Citizens/Family members lane when flying into each country with yourself.


Marriv before/after lighting the Menorah

Question: Does one need to Daven Marriv before lighting the Chanukah Menorah or can you light before davening? Why?
Comment: I think it depends when you light. Do you light at sunset or nightfall?
Answer: Mishnah Berurah (672:1, and in Beur Halachah ibid. ד"ה לא מאחרים) says that it depends:

If you usually daven Maariv before nightfall, then prepare the menorah ahead of time, and light immediately after Maariv (so you don't miss the proper time for lighting).
If you usually daven it after nightfall, then it's better to light first and then daven.
In the latter case, if you didn't have the chance to light before nightfall, then daven Maariv first (since it is a more usual mitzvah, so the rule of תדיר ושאינו תדיר applies; plus it includes the Biblical mitzvah of reciting Shema), and then light.
Comment: This is all true only according to those who, following Rabeinu Tam, light after nightfall.
Answer: I think heard HaRab Mansour say in today's Daily Halacha that you have al mi limsmoch to light candles before arbit.
I don't why yet though.
EDIT: I think I know why NOT- Tadir Kodem.


Is high-level, abstract information about individual moderator actions on C SE confidential?

Question: Is high-level, abstract information about individual moderator actions on C SE confidential? For example, a given moderator has taken moderator actions x times in the last week.
Comment: Why do you want to know that in the first place?
Comment: Moderators are elected on Stack Exchange. That means that a majority of the Community wanted these individuals to do what they do. It was a Community decision. And they do a lot of hard work in the background, free of charge, in order that we may have a functioning site. I am not aware that there is a job called 'Moderator Scrutiniser' for which the Community may vote to elect such a person. Unless I missed the voting opportunity.
Comment: Some users are able to 'access moderator tools'. This requires 10,000 reputation points.
Comment: @SpiritRealmInvestigator Related to my mods question here https://christianity.meta.stackexchange.com/questions/7054/are-all-the-mods-trinitarians . The mod I was talking to claimed info on mod activity is confidential. I then asked for a link to where it says info on mod activity is confidential. No response yet from the mod.
Answer: Mods do a lot of things, and it's not possible to quantify all of it, nor is it really all that meaningful to compare between mods.

User moderation (warnings, suspensions)
Handling flags
Cleaning up the site, closing questions, deleting posts and comments
Using the review queues (a moderation action everyone can do, but it still counts when the mods do it)
Crafting the custom close reasons, editing the help pages
Adding post notices, protecting questions, removing questions from the HNQ list
Commenting on problematic posts
Welcoming new people and making the site a generally welcoming place
Processing flag synonyms
Responding on Meta
Encouraging the community to use Meta
Identifying disputes within the community, weighing arguments, and putting forward arguments for policies (not unilaterally deciding policies)
Liaising with mods on other sites

The mods are not all equally active, nor do we all do all of these things to the same extent. There should be no expectation that all mods do contribute in the same ways, or that they spend the same amount of time here. It's not even like one action is always the same - some flags take 5 seconds to process, others could take half an hour to investigate,  decide a course of action, and then implement it. Some Meta posts take 3 minutes to write, others take an hour.
Some information is confidential, like user moderation actions. If someone is suspended we won't tell you why. Some of these actions you can observe yourself. Others you can't. Even when you can observe them you can't always know how much time or energy was put into it.
Finally, I see no reason to present a report on the other mods to the community. We're a team, and I don't think that would feel supportive to the other mods. At the moment I feel like we're adequate staffed for the amount of activity this site gets. If that's the case, then it doesn't really matter how we divide up the work. If anyone feels like moderation is taking too long, or if you think we're not spending enough time making decisions, then you can discuss it here, or raise the problems with SE staff.
Comment: Well stated if  stated  myself!
Comment: This contains some interesting information, but it doesn't directly answer the question. Is high-level, abstract information about individual moderator actions on C SE confidential? For example, a given moderator has taken moderator actions x times in the last week.
Comment: @OneGodtheFather I don't know if it's strictly confidential from SE's perspective, but it's practically confidential from ours.
Comment: @curiousdannii What do you mean, it's 'practically confidential'?
Comment: @OneGodtheFather I mean in practical terms, we're not going to tell you. At least not without you making a really good case for it.
Comment: @curiousdannii Thank you for that clarification - can you point me to where the community decided those rules?