Do the laws of logic exist independently of human or animal consciousness?

Question: Are the laws of mathematics and logic, such as if a=b, and b=c, then a=c just constructs of the human mind, or does the universe hold an innate logical structure to it, which the physical part of the universe must abide by?
Comment: +1 for a great first question .. for a good discussion of a related topic see [Do numbers exist independently from observers?](http://philosophy.stackexchange.com/questions/451/do-numbers-exist-independently-from-observers) .. there are innumerable supporters of both the 'mind dependant' and 'mind independant' ways of approaching about this topic, i think there is no better place to start than the work of [Plato](http://www.niu.edu/~jdye/forms.html). Also welcome :)
Comment: Vote to close: "We expect answers to be supported by facts, references, or specific expertise, but **this question will likely solicit debate, arguments, polling, or extended discussion**."
Comment: I'm new to this forum so I don't fully understand its purpose.  Should I edit to ask what have famous philosophers said on the matter, rather than asking the question directly?
Comment: Could you try to indicate how this is different from the already-existing question about whether numbers exist independently of observers? http://philosophy.stackexchange.com/questions/451/do-numbers-exist-independently-from-observers
Comment: Welcome to Philosophy.SE, by the way! Just in passing: the community tends to strongly favor very specific and practical problems encountered during the study of philosophy. You may wish to review our FAQ.
Comment: The question you have linked seems very similar to mine, except asks about numbers instead of the rules of logic more generally.  I'm not entirely certain that if numbers are human creations then it implies that logic is a human creation etc.
Comment: @JosephWeissman: while it touches on a similar concept, and may be interpreted as being a projection from a common 'Platonic Question Regarding Foundations Of Precise Reckoning', I would say that the questions are in practise as distinct as 'counting' is from 'reasoning'. If anything, this question is more foundational.
Comment: Frege wrote about this very thing, as did Aristotle (who viewed logic as a a mere tool, btw). I would argue that if these laws have no bear on the world, then our science and common sense have to go. It would involve denying number of facts. It is incredibly difficult to see how logical laws could be a mere mental fabrication without rendering reality unintelligible.
Comment: @DBK Perish the thought that a question in philosophy might spark debate. Can't have that around here!
Comment: Laws of logic are human invention. They are intrinsic to languages and knowledge but not to reality. They are used in language for describing the reality.
Answer: The answer is: we don't know. As the user Seldom indicated, Do numbers exist independently from observers? is a very related question.
What we do know is that there seems to be an incredible correlation between logic (and mathematics, for that matter) as we see it in the human mind and the way the universe behaves. For some reason, every time I make some logical conclusion in my mind, or even a calculation, "reality" seems to agree with it. And every time we discovered a discrepancy between our logic and reality, it was because we had erroneous models/premises.
So until now, we've had so much success that we induce that the universe seems to work with some kind of correlation with logic. Of course, there are several possible explanations for this:

Logic is a structure of reality
Logic is an abstraction made by humans looking at reality
Logic is a method used by humans to view and filter reality

Again, very similar to the numbers question.
Answer: Insofar as any of these relationships are defined and scoped by the human mind, so are they contingent upon the human mind.
Dependency/independency of some mind begs all the wrong questions and results in meaningful and senseless statements like "equality exists outside of space and time" and "laws of physics, equally, are part of the universe, regardless of human observation." These, in turn, result in all kinds of sloppy language.
Answer: This is not a meaningful question in logical positivism. The question of whether something "exists" or "does not exist", especially in relation to the existence of other inferred things, like human or animal consciousness, is an abuse of language in the sense of Carnap.
So this question has no answer, and it needs no answer, because it is not a real question. It's just a bunch of words you put together which fool your brain into thinking they have meaning when they don't.
Comment: It is fair to ask whether logic is more or less a feature of nature, just as we can ask whether mass is a feature of nature.    However, an answer is strongly suggested by distinguishing "facts" from "truths", in the sense of "not contradicted by fact".
Comment: @NieldeBeaudrap: The existence of logic is mathematically equivalent, modulo a choice of reasonable axioms and a small translation, to universal computation. Universal computation is measurable in nature, at least in finite approximations: we can build it, and we see it around us in biological things. This doesn't have any bearing on whether they "exist independent of consciousness" since this is not a proposition which has any bearing on the senses, or on the testable properties of logic or computation.
Comment: Computation is itself a tool. The idea that reality can be used for computation is the notion that we can harness physical processes to do something we want -- depending on the notion of intention. That intention is imposed on the tool by the user (e.g. ourselves). Inasmuch as we speak of tools, we are speaking of our own interpretation of how the universe may be harnessed to our own ends. Therefore we are speaking of a correspondance of the world with our ideas, and therefore speaks more of the relationship of our models to the things they represent, than reality in itself.
Comment: @NieldeBeaudrap: That argument would carry more weight if we didn't see natural computing machinery acting with intentionality in every cell in nature. The notion of computation does not require us doing anything--- evolution does it all by itself. Your brain is an obvious example.
Comment: There is a risk in attributing intentionality to things in reality. I'll admit that there's a philosophical problem hiding here, essentially the boundary between humanist/existentialist and materialist/mechanistic ways of speaking about the world. But remember that cells are presumably nothing but the byproduct of deep-time chemical processes which biased towards replicators; if these compute, why don't we say that all chemical reactions are computation, that gravity is computation, or that evolution is an intentional force of nature?
Comment: @NieldeBeaudrap: They are not biased toward replicators. Replication is not the main thing in evolution, computation is. Most chemical reactions are not Turing complete in bulk, they can't be programmed arbitrarily, my definition of life is when they are Turing complete. This is not an improbable event, a reasonable fraction of complex polymer reactions are complete. When a virus infects a cell, it shuts down translation. That's because it recieves a signal and it "knows" it's been infected, that's intentional. This kind of thing turns into our type of intentionality by gradations.
Comment: I don't think that's a good idea of "intentionality". Intentions, even if you want to reduce them to merely mechanical causes, can't so easily be reduced to everything that occurs in the universe. That's philosophically presumptuous and is putting the cart (a mechanistic system) before the horse (the facts of experience: even an illusion needs explaining). And computation is second to physics. Computers are physical objects operation in terms of physical laws. Computation is what humans ascribe to this artifact which mimics a mental operation.
Comment: @RobertLeChef: Computation is not necessarily second to physics, because physics invokes a notion of computation to do wave-function reduction in quantum mechanics (this is measurement). Whether this is a permanent thing in physics is a matter of debate, but I tend to believe it is. The computation doesn't mimic anything--- it is a mental operation of a primitive sort. When it is sophisticated enough, it is equivalent to that which goes on in your head. Every aspect of the human soul is a property of computers, and denying this is trivializing the transcendence of computation.
Answer: No, because we form the basis of the a priori.  That is, it is our consciousness which assesses and selects the building blocks of all logical systems, coming from the infinite sea* of [logically] equally-valid starting points.
(cf. Gregory Chaitin)
Answer: Basically note that we are living in a world that is certainly not self-contradictory and has rules for itself (some approximately discovered and some not even in any approximate way, maybe), but surely there should be some axioms for it to be based upon, as we can easily say something is possible (according to such axioms) and something is not possible (again according to that axioms) and such sentences are all meaningful (although there is aways the possibility that the one who says these expressions be wrong in respect to his objectives, so I am talking about the ontic knowledge and not epistemic, what really is and not what we think to know of reality). Thus, logic by its own is beyond the human kind, even humans exist based on the same logic that other things exist, they all belong to the set of possible objects in this world according to its underlying axioms, or say logic rule.
However, mathematics is perhaps the only branch of science which has not its base on witnessing the outside real world, you can imagine a set of axioms and logical rules to create your own self-consistent mathematical world, and substituting some of the axioms or logical rules by their antonym you may still be able to create another self-consistent mathematical world for your self and yet be happy with your creation. None of these logical rules may also have no counterpart in the outside world and that's it, logic exist in human minds and outside it!
Comment: That we live in a world that is not self-contradictory could as easily be a consequence that we built logic to reason about the world we see. The world consists of facts, not truths; truth is a question of the correspondence of our utterances to fact. That logic doesn't give us contradictions about the world — because it is feasible to find 'essentially correct' assumptions to reason from — indicates that logic is fit for purpose.
Comment: I do not agree with you, the word has been existed in a self-consistent way before human being come to it, if we were some super-existences to be able to also talk about facts yet we could talk about the possibles and impossibles of this world, indeed, if the world was not self-consistent it could not survive until we could experience it, there MUST exist an inherent logic behind this world defining its possibles and impossibles, it is according to that logic that nothing can exist in this world unless its anti-thing is absent in the same world.
Comment: The act of studying the possibles of this world is Science, although for non-super-xistences like us it is only epistemically about the truths and not facts, so only would bring about approximate knowledge of this world, its contained existences and the rules governing them (like their evolutions in the course of time, inter-relations and etc), and thus the logic behind it. (With the exception of mathematics branch of Science.)
Answer: I believe that the laws of mathematics are independant of thought. The names, symbols, etc that we assign to numbers are irrelevant, but the ratio between the radius and circumference of a circle, for example, are constant whether we observe them or not.
The laws of physics, equally, are part of the universe, regardless of human observation.  We spend time and effort trying to figure out what they are, not inventing them.
I would like to believe, also, that the laws of logic are similarly imutable.  The way we express them make it feel like they are human inventions, but I believe they are constant facts of reality that we discover and decide on conventions to express, rather than creating and enforcing rules on reality.
We would not observe water flowing uphill (observe, not just perceive), or 1 individual object coming together with another and forming a group of 3.  However, when it comes to logic, it is possible to perceive actions which seem to be founded on a belief that defies logic, making it easier to think that it is human-created.
Comment: That the ratio of a perfect circle's circumference to it's radius is constant is a result of Euclidean geometry. But there are no perfect circles (only approximately perfect ones); and it turns out that geometry isn't Euclidean (only approximately so). So that 'perfect truth', at least, is about fairy tale creatures which are wishful versions of what we encounter in reality; they are human constructs which are extremely useful caricatures, but not real phenomena.
Comment: Are you aware that the ratio is not in fact constant in hyperbolic geometry, or spherical geometry? Of the uniform geometries we know, it is *only* constant in Euclidean; and as General Relativity indicates that geometry is not Euclidean, there ought to be real-life instances — near massive bodies for instance — where the ratio is not 2 pi. Thus it is not clear on what theoretical basis you can claim that the ratio is constant in real life, except if you're speaking of the limited domain of everyday experience, in which geometry is approximately Euclidean.
Comment: would the downvoter care to comment?
Comment: I'm not convinced that there's no such thing as a perfect circle in nature, but the existance of one is irellevant to the point being made...

However on this: "That the ratio of a perfect circle's circumference to it's radius is constant is a result of Euclidean geometry." - we will have to disagree.  The ratio between the two measurements is constant, regardless of the number system used, or any other variable.  It is not a "result" of anything but the two measurements involved.
Comment: and does it scale? at plank distances, is a circle even physically meaningful? If some of the speculations regarding quantum gravity is correct, the spacetime fabric would be awash with topology change.
Comment: But maybe that what we find to be the rules which you believe are the objective rules that constitute the world and everything is just a model in our brain, and all models are wrong - but some models are useful.
Answer: logic is a tool used by beings capable of reasoning, we use this tool to create valid reasoning and  to understand valid reasoning, so when a human observes the universe he uses this tool to create a valid reasoning to explain what he is seeing, math is the lenguage we use to understand how natural phenomenons work, natural phenomenom exists  with or with out humans the way natural phenomenoms work is the same with or with out humans, mathematics is the language we use to translate the way this phenomenomswork into human understanding, so logic and math are correlated but they only exist when theres is a mind to use them.
Comment: so are you saying the law of identity is fundamentally not true? That's going to be a little hard to accept for certain classes of natural objects.
Answer: It's not like you can take a telescope or microscope and "see" logic. The "laws" of logic don't mean anything except inside a mind.  Just as the "laws" of physics are only meaningful inside a mind (brain).  They represent our understanding.
I think logic is not a "thing", its a process and activity of a mind/brain.  It's like saying "seeing" exists without eyes or "running" exists without legs. Something has to be "doing" the logic.
Let's start with computers.  What do computers do, if not logic?
I decided that they don't, and here is my argument, based on a definition of logic: logic is a form of thinking that attempts to solve a problem by manipulating meaningful symbols via formal rules and processes, to get a meaningful result.
So, whatever is happening in a computer, it's not really logic until someone has used it to solve a problem and/or assigned meaning to the symbols being manipulated by the logical mechanism.  And a computer can't do that part of logic without a human (yet).
Consider the abacus.  It can't do math until you have assigned a meaning (ie, number) (in your head) to each of the beads being moved. Without a human to interpret their meaning (ie, "read" the results), it's just a bunch of clay beads moving around on a set of rods.  The same thing can be said of Babbage's calculating machine.
And it's the same with computers. Until the results of the (much more complex) electronic manipulations in the computer is interpreted or assigned meaning, it's not really doing logic, or solving a problem.  Without a human to interpret (assign meaning to) the results, it's just a bunch of electrons moving around.
For example, an open circuit could just as easily mean "true" as "false"  The meaning is assigned as a convention, and the rest of the computer is built based on those conventions.  ASCII character 45 could just as easily mean "Z" as the letter "A".
In addition, there is the issue of defining the problem that is to be solved.  This is another step in performing logic that computer's can't currently do.  They have to be programmed to solve specific (human) problems.
Yes, they seem to have done a lot of thinking for you, but the problem the computer is solving was defined and programmed into the computer by a human, and the results of all that computer processing are meaningless without a human to read or interpret it (ie, consume the output), so I say computers are not really performing logical thinking.
In the future, computers may be able to be self-aware, emergently conscious,  capable of reflection, progamming themselves, and assigning meaning to their own results.  In the meantime, they are an extension of, and a tool for, human thinking.  They have been described as our "external brains".
When humans read, they are assigning/giving meaning to symbols on paper or some other media.  When humans think, they are manipulating mental symbols (concepts).  Logic (and math) is the manipulation of mental symbols following formalized rules, in order to to solve a problem.
So what do I mean by "meaning"?  Meaning is context.   Concepts are only meaningful in the context of simpler concepts they are built up from.  That is how sophisticated ideas are constructed.  That is how we learn, by gradually increasing the complexity of our concepts.
Some possible implications: Logic and Math are not something "out there" that we "discover".  The rules of logic and math are "constructed" by us, as our mental processes becoming more and more abstract and formalized.  This is why logical thinking is hard, and takes practice.
I also agree with the "embodied mind" theorists that many if not most of our simpler concepts are understandable and can only come from the experience (ie, context) of living in physical bodies.  For example, the concept of "color" is not meaningful without color vision, and a brain that is hard-wired to interpret it for us.
Nevertheless, I do think that logic and math are saying something universally "true" and non-relative to our human condition, in the sense that I think that if aliens were found, they would have developed logic and mathematically systems that are very similar, if not identical to our own (thanks goes to Carl Sagan for that idea).  The more abstract our math and logic become, the more universally "true" they become.  But, that truth cannot exist outside of a thinking mind.  It's not "out there" to be discovered, it's "in here" and constructed, by hard thinking.
Of course, what is amazing, and almost mystical, about logic and math is how well things "in here" allow us to predict and accurately manipulate things "out there".   That reality can be abstracted, and those abstractions re-applied back to real things is amazing.  As Einstein once said "The eternal mystery of the world is its comprehensibility."
Comment: Welcome to Philosophy.SE! The post is basically just an opinion. I would suggest editing it, citing sources and making more concise. Also, consider that the gist of what you suggest is already captured by other posts, and upvote those instead of adding a new post.
Comment: Well, duh.  Why would I need to document and cite, if it's my own opinion?
Comment: Pleas see https://philosophy.meta.stackexchange.com/questions/474/friends-we-are-not-philosophers ... the community consensus seems to be to discourage answers.
Answer: How can anything NOT be a creation of the mind? Just ask yourself this: IMAGINE no humans existed. Where would logic reside? Where would reason, truth, morality and numbers reside?
Comment: You're missing an important *just* in your answer to the question here. The question OP asks is if they can be *just constructs of the human mind*. The question you answer is whether they are *also* constructs in the human mind. Or at least you haven't spelled out anything else.


What is Inversion of Control (IoC)?

Question: Can someone guide me to some basic tutorials on inversion of control (IoC)? (preferably .net/c#).
I need some hands on code to wrap my head around it :)
Comment: IOC as in Inversion of Control -- The design pattern?
Answer: IOC, or inversion of control, is, in most apps, inverting the route through the code from UI to database. This si not a complete answer, but it is one of the easiest ways to get your head around the concept.
If you want to learn IOC, get into TDD, as you will find setting up tests a lot easier once you invert.
Example:
Typical flow of most .NET apps I have seen is something like this:
UserCollection col = BusinessLayer.Class.GetLoggedInUsers();
//Business logic
return col;

then business is like this:
UserTable table = DataLayer.Class.GetLoggedInUsers();
return table;

etc. This is all pseudocode. To use IOC in this example, you add an interface for the data layer class, like IUserRepository. You can use generics, and I would recommend underneath the hood.
You can then do something like this:
IUserRepository repository = SetUpRepository();
UserCollection col = BusinessLayer.Class.GetUsers(repository);

Why is this important? For testing, you can create a mock repository and feed it to the business class. The mock contains data that is always the same, which means you are exercising your code, not testing end to end.
If you want C#, here is a basic example on weblogs.asp.net :
Answer: Have a read of this excellent article  from Martin Fowler.
Also, take a look at the wikipedia article.
Dependency injection is the most well known example of inversion of control, which in short turns your code from this:
public class FileReader { }
public class Application {
    // inflexible concrete dependency
    private FileReader fileReader = new FileReader();
}

To:
public interface Reader {}
public class FileReader implements Reader {}
public class Application {
    // flexible abstract dependency injected in
    private Reader reader;

    public Application(Reader reader) { // constructor injection
        this.reader = reader;
    }
    public void setReader(Reader reader) { // setter injection
        this.reader = reader;
    }
}

Comment: +1 - though the wikipedia article is a monstrosity; it essentially conflates inversion of control with dependency injection (which as you say is only an example of the principle in action). Fowler's article specifically on IoC is much better - http://martinfowler.com/bliki/InversionOfControl.html.
Answer: To talk jargon, inversion of control is a pattern that supports, among other things, the single responsibility principle.
To get why all this is useful you need some exposition so bear with me.
Single responsibility basically means that your class should be as independent from other parts of of the system as possible, to minimize the impact of changing one part on the other. (You can also tie that back to the fact that changing the implementation should not trigger recompiling all files in your projects, as is the case when changing .h files in a C/C++ project for example).
The side effect is that you end up with lots of small objects which do one thing only, but very well (in an ideal world)
But in most cases, to carry out its work, one object needs to talk to other object: it depends on them.
First part of mitigating that is to separates implementation from interfaces. That means relying on interfaces (or purely abstract classes, depending on your language of choice), so that one object is not tied to the specific implementation of another.
So to use a canonical example, in the business layer needs, you need to carry out a function that needs access to
- The data layer to retrieve objects
- Some other service
- a logger to log information and or errors
In turn, every service or dependency has its own dependencies, which your class would need to be aware of even if it does not use them.
Depending on the amount of references, setting up the object can get out of hands fast. Now multiply that by the number of classes you need to write and you end up with a mess of things.
Using an IOC container basically helps you get rid of that mess.
When you need an object, you do not "new it up". Instead you ask the IOC container to retrieve it for you.
The container is responsible for delivering a functional object, ready to be used, whatever its dependencies.
What that means is that you class has no need of being aware of the dependencies of the classes it relies on, which cuts down on the tangle.
Moreover it does not need to know what actual class implements the services it relies on, which means that
- The service implementation can be defined in another project (dll or whatever), so modifying it will never impact you class
- The implementation can be a different one depending on the context (think about changing the database, or even going to a web service to retrieve information depending on the configuration or even the current state of the application).
To try and answer your other questions, IOC is a pattern. TDD and DDD are design methodologies, therefore one cannot equate the other.
But IOC is an invaluable tool to support TDD or DDD.
I know the acronym soup and the partial samples you can find around are not easy to grok. The best advice I can give you is to try some small projects on the side, prototypes that you WILL ditch, just to get a handle on those things. Not an easy way to go if you are looking at that for work, but absolutely worth it, if only from a personal standpoint.
Hope that helps a bit.
Answer: No, IoC is not DDD or TDD.
Martin Fowler's article is a good intro.
Comment: Agreed Greg, but they aren't synonymous.
Comment: No, I was on spot, so I am just adding comments proving I am a total dolt today.
Answer: For your question about what IOC is, Wikipedia has a fairly extensive explanation.
Regarding tutorials or examples this tutorial covers it quite well and has lots of exmaple code.
Answer: If you understand DIP (Dependancy Inversion Principle), IOC is cake.  I suggest learning the object oriented principles before you learn the patterns.  The core principles can be stacked like legos to accomplish any pattern.  Brandon Joyce
Answer: Inversion of Control is the abstraction of logic's structure. One approach (often used synonymously with IoC) is Dependency Injection, which abstracts references between objects. When objects are freed from an application's implementation details, such as which class implements which service, they are free to focus on their core functions.
For example, let's say you have a class that needs to map Foo objects to Bar objects. You might write this:
public class FooMapper
{
    public Bar Map(Foo foo)
    {
        // ...
    }
}

and use it like this:
public class NeedsToMapFoos
{
    public void MapSomeFoos()
    {
        var fooMapper = new FooMapper();

        // ...
    }
}

While valid, this is also rigid. NeedsToMapFoos only cares that mapping occurs, not that it occurs in any specific way.
We can represent the concept of "operation sans implementation" with an interface:
public interface IFooMapper
{
    Bar Map(Foo foo);
}

and declare a dependency on that operation:
public class NeedsToMapFoos
{
    private readonly IFooMapper _fooMapper;

    public NeedsToMapFoos(IFooMapper fooMapper)
    {
        _fooMapper = fooMapper;
    }

    public void MapSomeFoos()
    {
        // ...use _fooMapper...
    }
}

Now NeedsToMapFoos has less knowledge, which means it is less complex. Instead of performing administrative duties, it is free to focus on the business case.
Well-factored objects like this are also more adaptable. Just as diamonds are rigid and clay is malleable, internal structure determines response to change.
Finally, logic written in this style is also flexible. Let's say FooMapper.Map is an expensive operation and should be cached. You can use the decorator pattern to wrap the existing implementation and seamlessly pass it to NeedsToMapFoos:
public class CachingFooMapper : IFooMapper
{
    private readonly IFooMapper _innerMapper;
    private readonly IDictionary<Foo, Bar> _cache;

    public CachingFooMapper(IFooMapper innerMapper)
    {
        _innerMapper = innerMapper;
    }

    public Bar Map(Foo foo)
    {
        // Read bar from _cache. If not there, read from inner mapper and add to _cache.
    }
}

// Usage

new NeedsToMapFoos(new CachingFooMapper(new FooMapper()));

What is Inversion of Control (IoC)?


Which is faster: Enter the Battlefield Effects or Activated Abilities?

Question: What happens if I play a creature that destroys all other creatures when it enters the battlefield and in response, an opponent activates a creature ability that sacrifices his creatures to destroy target creature? Is his effect fast enough to destroy my creature, or does my creature destroy all his creatures first?
Answer: Your opponent can destroy your creature first; but his creatures will still be destroyed as well.
There is no notion of "faster" in MTG. Some people might say an instant is "faster" than a sorcery, but that is only because you have more opportunities to cast instants than you do sorceries. All abilities and spells have pretty much the same rules regarding how "fast" they are. (Mana abilities and certain game actions like playing a land are an exception).
When your creature enters the battlefield, its ability is triggered. The trigger goes on the stack the next time a player would get priority, which makes the stack look like this:

Destroy all other creatures

Then each player gets priority, and your opponent has a chance to activate his ability. If he does so, the stack now looks like this:

Destroy target creature
Destroy all other creatures

If no one does anything else, the top item on the stack resolves. Your creature is destroyed. Then if no one does anything else, the next item on the stack resolves. All other creatures are destroyed.
It doesn't matter that your creature dies first; its enter the battlefield ability still happens:

112.7a Once activated or triggered, an ability exists on the stack independently of its source. Destruction or removal of the source after that time won't affect the ability.

Recommend reading through this question and this question if you want more details.
Comment: The stack, it always boils down to the stack. When in doubt, look at the stack. Good answer.
Comment: @Mast or layers....
Comment: Layers are exclusively for replacement effects. If it's about when you can do something, it usually about priority. If it's about the order in which things happens, it's about priority, the stack and/or steps (game actions).
Answer: Gendolkari beat me to the punch but I'll post this regardless:
His ability will resolve first in this situation however both effects will happen.
What happens is that your creature will enter the battlefield and put his "Destroy all other creatures" trigger on the stack. In response, your opponent can use his creature's activated ability to sacrifice it and put a "Destroy target creature" effect on the stack, on top of yours. You'll have the option to respond to that as well but assuming both players pass priority, the stack will look like this, from top to bottom:

Destroy your creature
Destroy all other creatures

The top will resolve, destroying your creature. You both (starting with the active player) will have another chance to do stuff but if you both pass, the "Destroy all others" trigger will then resolve, doing exactly that.


What was the silver "valhalla spray" in Fury Road?

Question: Five of us watched Mad Max: Fury Road and were unsure what the silver "valhalla spray" was- certainly it had to do with Valhalla, but.. is it paint? Freezing spray? What is its significance, and how is it related to the use in the movie?
Comment: reviewing some reviews, it's being called "chrome" and some links are made to the worship of car culture. that may be as good as this answer can get. @BrettFromLA
Comment: I believe it was chrome, and one of the characters may have said that, but I'm not certain.
Comment: by the way, you can get the paint on Amazon, It goes by the name: Wilton Cold Mist Silver Spray
Comment: They do say chrome when they do the spray. Presumably to relate to the reliance on well-oiled machines and their interest in making fancy cars.
Comment: Congratulations, this question is the winner of the [corresponding topic challenge](http://meta.movies.stackexchange.com/q/1807/49)!
Answer: They are not huffing paint. It has nothing to do with "huffing." They are spray painting their "grills" (teeth) so they will be (as they say in the film) "shiny and chrome" when they go to their Valhalla. Remember, in their Valhalla, they ride forever. It's a kind of statement...it has nothing to do with any toxic or intoxicant effect.
Comment: Having watched the movie twice in the last few days, I gotta say this seems to me at least, to be the correct answer.
Answer: Movies.com interviewed director George Miller, where he revealed his inspiration:

I saw a documentary where young [Cambodian] soldiers would go into
war, they had little jaded deities -- and before they ran into battle,
they put them in their mouths and just held them with little straps.

Apparently:

This was their ritual before battle -- that, like the Buddha, the chrome paint will help lift them to a higher place. It'll help bring them to Valhalla.

And from an interview with actor Hugh Keays-Byrne, who plays Immortan Joe:

What exactly is the silver stuff you spray on Nicholas Hoult's face?
That's like a very euphoric drug.

As George Miller explains further in the interview:

[Immortan] Joe was a member of the military who used his leadership
skills to build a cult.
"He was a colonel named Joe Moore. He was military, and he organized everybody, eventually being
able to exploit a cult as he took over this dominance hierarchy."

Speculation:

My guess is that cult leader Immortan Joe came up with the "Valhalla" explanation to manipulate his followers into drugging themselves. The War Boys don't actually know that the spray contains a drug. They genuinely believe it will help them get to Valhalla.
Comment: When you say "chrome paint", do you mean silver or yellowish in color?
Comment: The interview with Keays-Byrne doesn't seem as if it was intended to be realistic.  For example, he's faking a character.  In addition, an actor's version of events doesn't always have to be canonical.
Answer: Ok so from what I gathered, they're effectively 'huffing paint', in order to make their suicide easier to go through with. It's narcotic effects make them more willing and geared up to 'enter Valhalla'. Notice how both Nux and the other War Boy both widen their eyes and smile maniacally after they've been sprayed. The visual element is likely a reference to their obsession with cars, so they're 'chromed' up, but I took it to be more for it's effects than it's look.
Comment: I'm not sure that "filling your mouth with paint" is an effective method of huffing... though I'm not an expert by any stretch of the imagination.
Comment: This makes no sense. Drinking paint is not the same as huffing it.
Comment: I just assumed that it was a mixture of that and, as others have said, the 'chroming up' element. If it's near the nose, it's probably going to be inhaled, and I imagine it's probably quite strong/toxic
Comment: Huffing normally had the can upside down to breathe in the propellant, not the liquid being propelled.
Comment: I don't think it was primarily for narcotziation (it probalby didn't have a reaosnable effect) and more of a ritual thing, like many of the things they did and like you yourself explained in the latter part of the answer.
Answer: I think maybe people are looking too much into the spray.
Mad Max IS visual storytelling at its best.  The spray could be their ritual before they commit suicide (enter Valhalla) and perhaps they use it to mark their bodies so they can be identified when they enter their next life. But I also like the idea that it gives them a quick high (i imagine inhaling any kind of solvent would make you go a bit dizzy) so their suicide is slightly easier on them.
Writing this I had another thought: They say 'Witness me' before they kill themselves... maybe the spray is a visual indication to everyone too far away to hear that they are about to enter Valhalla?
But until we get a quote from the Director it's all just interpretation and as a community... I'm sure someone will hit the nail on the head and give everyone a satisfying answer.
Comment: @Daft While I appreciate your patronising quotations... the origin of the spray is never divulged in any detail. With most visual films, it's all down to interpretation. I offered a number of 'ideas' of possible reasons for the spray. Whether the author of the question is happy with these interpretations is up to them, not you.
Comment: Please everybody calm down a bit. There is no need to put sarcastic statements into the answer or to accuse anyone of any generic statements about the relevance of film-studies or anything. While this answer does not provide an evidence (like *none* of all the answers), it does provide at least reasonable argumentation *based on the movie*. This might not make it an authoritative answer, but it also doesn't make it *not an answer*. But neither would I agree that all answers to any question of such kind necessarily would have to be mere interpretations...
Comment: "until we get a quote from the director": Immortan Joe annoints Nux at one point by spraying him with chrome paint and offering a benediction. There is no reason to wait for the director regarding the significance of the act. The only point lacking is any supposed narcotic effects, which are probably trivial.
Comment: _I think maybe..._, _To me, this film..._, _I think the spray is..._.  This is not a good answer.
Answer: Just as everyone has said, but I'm assuming you're more confused at why they did it. All those people who are painted white and spray their mouths (I forgot what they're called) are bred at a young age to believe everything Immortan Joe told them. He basically created an army that would do anything for him. Everything they believe in is because he's told them that, they risk their lives because they think Valhalla is real. Some people hated it because of that aspect, I personally think they just didn't understand it. It's like how Kim Jong-Un makes North Korea believe he's a gold medalist, doesn't poo etc. it's a pretty great way to create an army, they're bread to defend and attack for you. The paint is just a metaphor for what they have been told they'll become and they do it before they die in an act to help their master (Immortan Joe). Shiny and Chrome
Answer: Its simply to "pretty up" for their acceptance in Valhalla. It has nothing to do with a drug, suicide or the like. The one character also refers to shiny things a few tines in the movie especially when seeing the wives at the truck. Its simply more of a tribute to Valhalla and its pretty. Think of it as their "gold" as far as being pretty, valued, of high significance. Not a drug or related whatsoever
Answer: They are huffing. They are out of the tree. It is the equivalent of soldiers in WW1 or WW2 having a shot of rum before they went into battle to face there death.
Answer: It's called chrome, and it's main purpose is actually so they can spit fuel into the engine, as when they don't have the spray they can only do it for a short time.
Comment: Can you explain why you think this is the case? I don't see any correlation between the scenes where they're spitting fuel into the engines and when they spray the chrome.
Comment: Steve, I think you're wrong here. The chrome spray is directly linked to 'suicide' and nothing to do with spitting fuel into the engines, as the few moments where they are spitting fuel, there is no chrome spray in sight. Quite a conclusion jump you've made.
Comment: If you re watch that scene you'll notice that the guy is actually sipping fuel and spitting it into the intake. The chrome spray has nothing to do with it.


Install on Acer Aspire One D255E

Question: When I try to install via USB all I see is a cursor at the top of the screen after a brief flash that show Linux being initialized.  The system just hangs.  This happened when I tried Lubuntu as well.  Any ideas how to install on my brick?
Comment: Have you tried to disable graphical boot to see what's going on?
Answer: I installed Ubuntu Desktop Edition on my Acer Aspire One and it works perfectly. I also got in troubles with the USB image but I did another one image and it works for me
Answer: I've heard that instead of installing the netbook version you should install the full desktop edition of 10.10 (32-bit).  I've done that on my newer HP Mini netbooks, and it works perfectly (also done this with slightly older Acer netbooks in the 1.5 - 2 year old age range).
Answer: On some Aspire netbooks you need to enable you need to turn on network boot in the BIOS.
See more here.

Install on Acer Aspire One D255E


Seeking traditional coffeehouse in Vienna , extremely close to public transportation

Question: I am disabled, so 300m is the absolute maximum, when I move on foot, 50m is of course even better;)
Comment: Having been in Vienna, I would be very much surprised if you do not find coffee houses near bus stops, but I am not familiar enough with the city to help you out.
Comment: Choosing to leave this open. While it may indeed be broad, the user needs help. Perhaps someone knowledgeable of the country and city could explain how best to find what he wants for himself?
Comment: Associated question http://travel.stackexchange.com/questions/61330/seeking-starbucks-in-vienna-very-near-to-public-transportation/61338#61338
Comment: Voters: if you were tempted to close as "too broad" because you know Vienna and know that there are hundreds of traditional coffee shops close to public transport all over the city, then *that's the answer to the question*. Do what Pont has done in cases like this, and *explain* that in an answer. Leaving an asker who *doesn't* know this guessing is just mean-spirited.
Answer: I think you'll find a lot of places that satisfy your requirements: Vienna has many coffee houses and an excellent public transport network. If you pick a random location in the central district, it's more likely than not to be under 300m from a transport stop. With that in mind, it's not really practical to assemble an exhaustive list, so I'll just give an example to demonstrate.
Picking Stephansplatz U-Bahn at random, I see from the Google map that it's about 100m from Café Hawelka in Dorotheergasse, which is a thoroughly traditional coffee house. The same stop is about 50m from a branch of Aida. Aida isn't really a typical coffee house (it's a franchise, for one thing) but it's certainly a solid Viennese institution with excellent coffee and cake, and very popular with locals.
Answer: There's Cafe Central, which according to Google Maps is about 100 meters from the Herrengasse U-Bahn station.  Someone on Tripadvisor calls it "a must-see for anyone wanting to capture the essence of Vienna."
Go about the same distance in the other direction, toward the Michaelerplatz, and you'll get to Cafe Griensteidl, known in the 19th century as "Cafe Groessenwahn" for all the writers ("megalomaniacs") who would hang out there.
There's a coffee shop called Espresso Schweden directly across from the Schwedenplatz metro stop.  AFAIR the stop is above ground, so perhaps the walk would be easier.  Not as well-known as Cafe Central, although the ice-cream shop next door has some tradition behind it.


Target Recognition for Microcontrollers

Question: I'm building a device using microcontrollers, and part of the device necessitates target recognition. That is to say, if there are three targets, A B and C, I want my device to know when I'm pointing at no target, or Target A, or Target B, etc. I was thinking originally of finding different wavelengths of IR LEDs and putting them around each target (each would have a different wavelength) but I want this to ideally be able to reach across a room, let's say 30 ft. Is this feasible with IR receivers and transmitters, or is there a better alternative? And, is the varied wavelength idea with these transmitters feasible otherwise?
Comment: think about this .... three TV remote controls .... each one has a different button pressed ..... your pointing device contains an IR receiver .... use optics to "see" only one remote control  at any one time
Comment: @jsotola, that looks very answer-ish to me.  make it one?
Comment: it may be answer-ish, but it is only a hint to direct thoughts towards using coded IR transmitters ..... actual TV remote controls may not work, because when a button is held down, the transmitted code varies with the manufacturer .... with some, the button code repeats, but with others "repeat last button" code is transmitted
Answer: An IR transmitter is a circuit and an LED.  An IR receiver is an optical filter (essentially a piece of colored plastic, but the "color" is in the IR), a phototransistor or photodiode, and a circuit.
To make what you want using different wavelengths, you need to find IR LEDs with non-overlapping emissions (so they don't interfere with each other), and you need to find three different kinds of IR filter material, each that passes the light from one of your LED types but not from the other two.
Just off the bat, this doesn't sound feasible for a commercial application, much less hobby.  If you were getting a PhD in robotics and had a friend down the hall researching optical filter materials -- maybe you could do it.
The suggestion of using a TV remote would work, more or less, although TV remote receivers have automatic gain control, so it would be difficult to make fine distinctions in direction.
Part of my background is in radio and communications signal processing, so the technique that leaps to my mind is to have each LED beacon use identical LEDs, but pulse at a different frequency.  You'd want the frequencies separated enough for easy discrimination with filters, and probably not harmonically related.  So, for example, 50, 55 and 60kHz.  If you build the receiver circuit correctly you can amplify the output of the photodetectors with a circuit that has a passband of 50-60kHz, then either run them into three separate discriminator circuits, or run them into an ADC that samples sufficiently fast (200kHz is my knee-jerk "fast enough" suggestion, but there's wiggle room there) and do the discrimination in software.
Doing the "sample first then process in software" option requires a sufficiently powerful microprocessor to do the discrimination -- my gut feel is that anything 8-bit would be woefully inadequate, but an ARM Cortex M4 or better core running fast and with reasonably efficient code would do it.  It requires a healthy dose of DSP chops to write the software.
Doing the "discriminate in circuitry" option requires a filter bank of three filters centered on the pulse frequencies, with reasonably well-balanced gains, followed by some sort of amplitude detection into three times as many ADC channels.  It requires a healthy dose of analog circuits chops to design the circuits, and you'll need to deal with component variation and find the board space for the circuitry.
No matter how you do the discrimination, once you get your "channel per target" into your actual direction-finding software, you can use whatever technique would work for a single beacon to find each one of the three.

Target Recognition for Microcontrollers


Is immigration causing unemployment among low-skill workers in the UK?

Question: Immigration policy is a hot topic in UK politics, but is it actually costing British jobs?
Comment: Please add something to show that this is a widely held belief that people should be skeptical of.
Comment: @LarianLeQuella it's a very notable claim of parties like UKIP--but I'm sure that many similar claims are made about Mexicans in the US, for example.
Comment: @JanDoggen Wow, confusing percentages with millions is a fail even by Daily Mail standards.
Comment: Well that is practically unavoidable if you believe the figures published by the Daily Mail ('Daily Fail'?) this november 2013: *14.6, 9.5, 4.6 and 4.2 million immigrants from India, Pakistan, Nigeria and the Philippines got a UK citizenship in 2012*. It turns out these numbers were the **percentages** of British citizenships granted across these countries ;-), from a total of 194,900 people. (Could not find the original error any more, only the corrected figures http://www.dailymail.co.uk/wires/pa/article-2840260/More-migrants-given-UK-citizenship.html)
Comment: @Sklivvz - you are correct. I'm too lazy to search ATM but I saw tons of such claims for USA.
Answer: I'm not sure the British have such a big problem with unskilled migrants as they like to think.
This report highlights the trends in the UK low-skilled job market from the 80s/90s to 2013:
Migrants in low-skilled work
Migration Advisory Committee
Full Report
July 2014
It seems to suggest that migration patterns are consistent across the skill spectrum and that migrants have not significantly or unfairly displaced UK born workers.
Here is a selection from chapters 3 ("Recent migration to the UK and factors affecting this") and 4 ("Employment in low-skilled work"):

3.4 Migrants accounted for approximately 16 per cent of all low-skilled employment aged 16-64 in the UK, slightly above the
  overall share of the population but broadly in line with their share
  of all employed persons, regardless of skill level.
3.8 One million migrants in low-skilled work in 2013 have come to the UK within the last ten years. Half of these came from Central and
  Eastern Europe, following EU enlargement in 2004 and 2007. Over
  300,000 came from Poland, who account for around one in six of all
  migrant workers in low-skilled employment and almost one in three of
  those who arrived since 2004. Even so, by 2013 migrants from Central
  and Eastern Europe still accounted for little more than a quarter of
  all foreign born workers in low-skilled occupations.
4.4 We also considered the 'hollowing out' of the labour market and while the evidence is not definitive, there have clearly been
  substantial changes in the type of jobs available. This has important
  implications for the composition of the labour force by gender and
  progression up the skill ladder.
4.5 While the overall UK employment rate has been stable since 2000, there have been important shifts by gender and age. The employment of
  UK-born aged 50 to 64 has increased, while the employment of other
  UK-born groups has declined. These changes in employment correspond to
  changes in population, with the exceptions of the 50 to 64 age group,
  for whom employment has increased more than the growth in population,
  and the under 25 age group, for whom population increased but both
  employment and participation fell.
4.6 It might be thought that the decline in employment for the under 25 age group is associated with greater competition with migrants for
  low-skilled jobs. While this is possible we note that the youth
  unemployment rate is comparable to 30 years ago when there was far
  less migration. There are other factors to consider as well, such as
  the increase in the number of 16 to 24 year olds choosing to stay in
  education, which therefore affects the number that will be in work and
  participating in the labour force.
4.21 The decline in low skilled employment among the UK-born was more than offset by a 2 million increase in high skilled working.
  High-skilled employment among migrants also expanded considerably from
  1 million in 1997 to 2.3 million by 2013.
4.54 In contrast to the older age group, while employment of men and women aged under 25 has decreased, their population has increased.
  This results in large decreases in their employment rates of 14
  percentage points for men aged under 25 and nine percentage points for
  women aged under 25. We explore reasons for these changes, such as
  greater participation in tertiary education, just below in section
  4.6.
4.55 Overall, between 1997 and 2013 the employment rate for the 16 to 64 UK- born population has increased by half a percentage point and
  this would have been affected by the recession post-2008. Changes in
  population and participation rates by gender and age have been largely
  offsetting such that overall the UK-born employment rate appears to
  have been relatively unaffected during the period of significant and
  rapid migration to the UK. However, although the overall measure has
  hardly changed, there have been some important shifts by gender and
  age, where employment has increased for some groups and decreased for
  others.
4.63 It is possible that a contributing factor to the changes in youth unemployment and NEET rates is the increase in migration to the UK
  during the mid-2000s. This is particularly relevant for low-skilled
  employment, since as Office for National Statistics (2014k) points
  out, young people are more likely to work in the lowest skilled jobs,
  particularly elementary occupations and sales and customer service
  occupations. Young people could, therefore, experience greater
  competition for such jobs, due to the increase in migrants also
  looking for work in these areas.
4.64 However, at national level the youth unemployment rate has been at similar levels before, during a time of much lower migration. The
  unemployment rate for 16 to 24 year olds was the same in 1984 as it
  was in 2013 (Office for National Statistics (2014k)). In fact, the
  proportion of the total population of 16 to 24 year olds who are
  unemployed is lower in 2013 than it was in 1984, 13 per cent compared
  to 15 per cent.
4.86 Many 16 to 24 year olds will not want to pursue further academic study. It is important for this group that they are able to gain
  requisite skills through vocational education and work experience.
  Wolf (2011)'s comprehensive review of vocational education in England
  "found conclusive evidence of serious problems in current provision:
  problems which impact directly on young people and their futures," and
  came to the damning conclusion that "too many of our young people are
  being short-changed."
4.110 It might be considered that the decline in employment for the under 25 age group is primarily due to greater competition with
  migrants for low-skilled jobs. While this is possible we note that the
  youth unemployment rate is comparable to 30 years ago when there was
  far less migration and that the state of the economy and level of
  demand play important roles in labour market outcomes for 16 to 24
  year olds. In addition, academic attainment, work experience and soft
  skills all play a role in determining a young person's access to
  employment and training opportunities. Basic qualifications,
  especially English and mathematics, are incredibly important for their
  employment prospects. There is evidence to suggest that the skills of
  young people in these areas are placing them at a disadvantage in
  today's labour market.
Comment: Could you spell it out a bit more? I'n not sure how this report shows whether "immigration is causing unemployment" (the question), nor even that "the British may not have such a big problem as they like to think" (your counter-claim).
Comment: Your answer's data contradicts your claim. ` Migrants accounted for approximately 16 per cent of all low-skilled employment aged 16-64 in the UK,` - that means UK unemployment is significantly impacted among that demographics, to the tune of up to 16% (you also have added complications of unemployment figures NOT counting those who gave up looking for work, partially because they realize immigrants undercut them on price)


How should I prepare doors and windows for painting?

Question: I'm mostly interested in what is the best way to protect the wood from bad weather, but any other advice on how to improve overall quality of work would be appreciated.
Comment: Outside or inside? Is there are paint or enamel or anything on the wood already?
Answer: Strip off all the old paint and sand the wood very well. Then use a good primer that seals the wood that water cannot enter it. Finally paint the wood in a colour of choice.
Answer: Scrape, then sand the wood well. You don't need to remove every last trace of old paint, but if you leave too much behind the new paint is liable to crack and flake quite quickly, especially if it's outside and the old paint isn't particularly clean.
I like to use a Skarsten scraper for this, there's plenty of alternative options, but I'd recommend leaving a power sander until last.
If you're renovating an old sash window and really want it to last, take the sashes out, remove the glass, and get them stripped. It's not so hard to re-glaze a window, smoothing the putty so it's neat is really very relaxing.
Then prime. I like to use a good quality aluminium-based primer, you can't afford to scrimp on this as it's the primer that really stops the weather getting to the wood. Use two coats, three if you're by the coast or have extreme weather where you live.
Undercoat next. Perhaps I'm a sucker for marketing ploys by manufacturers but I choose an undercoat from the same supplier and range as the top coat I'm going to use. A family member used to work in the paint business and they spend a great deal of time making sure the chemistry of the two components match.
Finally, top coat. Two coats, again, gives a proper depth of colour.
Last of all, keep a careful eye on the wood when you clean the windows. It really pays to make sure that the corners and the joints are sound, and if necessary a little touch-up each autumn helps.
Answer: if it's outside follow txwikinger's advice. If it's inside, it also depends what type of wood and whether you're going to paint it or stain it?
If you're planning on staining a soft wood (e.g. pine) then you'll need to use wood conditioner to seal the grain and then stain (no need to use wood conditioner of hard woods, e.g. oak) after you stain it, you can use polyurethane for finish.


Good online poker app to play with friends?

Question: I am looking for a good online poker application/website simply for playing heads up with my friends for fun. A few friends and I use the game-pigeon poker app in apple i-message for our phones, but I find that it is very slow to have to send texts back and forth even for the smallest action. Is there any "for fun" online poker app preferably not on mobile?
Answer: On like Play WSOP you can join a table with your friend but you don't get heads up.
Are you a programmer? It would be pretty easy to build one. Problem is dealer could hack and see the cards. Don't even need a database.
For security would need an external server to be the dealer. So there is a cost of hosting but that is pretty cheap.
I started to write one for Windows Store (both mobile and PC). Do you think you would pay for the app. Entry level only get to play against a random player.
For an upgrade fee it would store all your hands, give you statistics, and private games. It would also have a learn mode to give you outs and pot odds for calling.
It would not support real money but if you and you friend agreed to a cash transaction that is not my business.
When I searched to market there was nothing like this in the Windows Store.
Comment: I am studying to be a programmer, sounds like a fun project actually. I don't think I would personally pay for an app like that but that is not to say that others wouldn't.
Comment: Ouch.  That is why I did not do it.  Most people do not even want to pay $1.
Comment: @Clarko If you look on codereview you will see some of my poker tools.
Answer: Pokerstars have a system called Home Games, or Clubs I believe and you can create a house group where your friends can join and setup a game for play money or real money etc. It's pretty good I use it with my uni mates over summer when we all go back home. Hope it helps
Comment: is this available in the USA?
Comment: @Clarko I think it is but you can only use play money but i'm not sure


What does RNG mean?

Question: I think I've heard it in the context of speed-running Pokémon and other games. I think it means luck. It can be found around Arqade, but no one has asked what it means (as its own question).
Comment: Direct further comments here: http://meta.gaming.stackexchange.com/questions/10382/what-does-rng-mean-comments-extension
Comment: I may be dyslexic because I have always thought of RNG as "randomly generated number" in my head...
Comment: The two answers so far have expanded the abbreviation, but they don't explain what random number generators have to do with video games. I'd add this to the original question instead of as a comment, but I don't want to bump the question and garner more downvotes.
Answer: RNG stands for random number generator.
It is often used in speedruns, to say that you had luck (like "I got lucky with the RNG") or that a section can be quite random ("The RNG in this section can be a pain").
You might also hear rngesus ("pray to rngesus that it works") - basically praying for good luck.
Comment: Don't forget to pray to the RNGods.
Comment: Notably in the context of Pokemon and other RPG-esque games (although not in the context of speed running), RNG is also commonly used to refer to (P)RNG abuse, that is, calculating and forcing specific "random" outcomes thanks to the fact that RNGs aren't actually generating *truly* random numbers, but rather pseudo-random numbers which only *look* random.
Comment: don't forget the dreaded [desire sensor](http://www.urbandictionary.com/define.php?term=Desire+Sensor)

What does RNG mean?


Is there an example of one picture painted by different painters?

Question: s there a (famous) example of the same art work created by different painters? I mean the following situation: painter X starts a painting, painter Y continues the same painting, and painter Y finishes it. What is the final result? Mix of styles? The homogeneous work looking like a product of a single artist? Anything else?
Comment: This is normal for artistic workshops.  I think *everything by Bernini* is an example.
Comment: As noted, leading artists often had a lot of helpers. Any of a number of masterpieces had multiple people contributing work on them. Just like a general contractor doesn't build your house all by themselves.
Comment: Can you bring some specific link / name of the painting so that i can locate and look at this kind of art work. So that I can be sure that at least two painters contributed to the same work.
Comment: See [this article on Rembrandt](https://www.nga.gov/research/online-editions/17th-century-dutch-paintings/essay-issues-attribution-rembrandt.html) as an example.  For many artists, it was a business, and you don't want to waste the best talent doing the boring bits.
Answer: Historically, there are thousands of paintings that were painted by multiple artists. During renaissance and baroque, art and painting was more of a craft and trade than an expression of the artists' message  as it's seen today. Artists had workshops with apprentices and assistants. Training included copying the master's work and painting parts of or even the whole commissioned paintings. The goal was to create what you describe as "homogeneous". As the signature (if existent) also didn't necessarily mean authorship, but could also indicate origin (compare to stamps on porcelain) and the master's approval, modern art historians  still struggle with assigning an individual work to the actual creator. (See the Wikipedia article about Rembrandt under "Expert assessments".)
If you are looking for a more recent collaboration where the individual artists' contributions are very visible, I recommend you research the collaboration between Andy Warhol and Jean-Michael Basquiat in the 1980s.
Answer:
Can you bring some specific link / name of the painting so that i can
  locate and look at this kind of art work.

Morning in a Pine Forest by Ivan Shishkin is a fairly famous example.

The Morning in a Pine Forest (Russian: Утро в сосновом лесу) is a
  painting by Russian artists Ivan Shishkin and Konstantin Savitsky. The
  bears were painted by Savitsky, but the art collector Pavel
  Tretyakov effaced his signature, stating that "from idea until
  performance, everything discloses the painting manner and creative
  method peculiar just to Shishkin", so the painting is now credited
  solely to Shishkin.
Answer: To name another: Rubens-Snijders-Van Dyck. source: www.snijdersrockoxhuis.be
Comment: Good to see a new face! Is there any way you can add a bit more meat to this? Our users generally don't like to see one line answers with links. If that website were to go down tomorrow, what on there would you want our readers to know about this person?
Comment: Good stuff! I really didn't know that about Rubens. As @tum_ suggested, could you perhaps click that "edit"  link under your answer and add that content there?
Comment: Torre de la Parada @ Madrid-Spain, Snijders did mainly the animal figures for Rubens, who did the supervision.
Comment: please edit your answer instead of creating extra comments. I have suggested an edit to your answer (proper link).


How can I quiet my dryer vent from the outside?

Question: I have a Whirlpool electric clothes dryer and it is under 5 years old.
 When it is drying it makes a "whirling sound" that is especially loud from the outside where it is vented. My neighbor is constantly complaining about it. We shoved a large rock up in the vent from the outside and that helped a lot, but the clothes did not dry properly as they should have on the normal setting with the normal amount of clothes that I always dry.
Comment: A [muffler](http://www.midas.com/Portals/0/Services_Images/17_Mufflers_AskMechanic.png)?
Comment: @Tester101 they actually do make mufflers specifically for exhaust fans
Answer: Absolutely do not block the vent - this could cause a fire!
The first thing to check is that your duct is free of lint and other debris.  If it is a plastic duct then I wouldn't even bother cleaning it and instead would replace it with a metal one. A rigid duct line is probably better than a flexible one but is a bit more difficult to work with.
Check for any unnecessary bends or kinks in the line - the straighter the better as bends restrict the airflow and result in additional noise.  If it is a collapsible/flexible duct, make sure it is fully extended and trim off any excess ducting.
If possible you might consider relocating the exhaust further away from you neighbor.
Comment: My experience is that while ridgid ducts are the best, a good quality metal flex duct stays clean MUCH better than any plastic duct.  Plastic duct should never be used for a dryer!
Answer: Do NOT block the vent. Stuffing something into it is a sure way of setting your home on fire in only a short time. And your clothes won't dry either. Ok, when the fire starts, things will get hot, but then the fire company will wet it all down. It won't be a happy occasion.
Seriously, what I'd offer is to create a muffler. I'd build a large box around the end of the vent that can muffle the sounds. Put some holes in the box, that do not aim at your neighbor. Make it so you can open it and clean out any lint that accumulates. Make sure you check this periodically.
Answer: I am a neighbor with this problem which became a huge issue and not addressed immediately. Solution: Rigid pipe, only two bends, short as possible. Moved exit hole to  grassy backyard rather than aimed at a concrete driveway that amplified sound bounced on neighbors house. It was the right thing to do. Fixed it. Also put a hood on exit hole to direct sound to the ground rather than the just the flaps - dryer works faster now and it lowered bill. We also agreed not to do laundry after 10pm because its not a hard thing to do and saves cop calls!
Answer: Generally to quiet exhaust flows you add a big expansion area into the pipe, like a car muffler or even a gun silencer. I don't think this is a good idea for a clothes dryer, as it will accumulate lint, which can become a fire hazard.
I'd suggest using some sort of a structure to block the direct "line of sight" between the exhaust vent and your unsettled neighbor. This could be a section of fence or a shrub. be sure to keep a couple of feet of clearance between the exhaust vent whatever you put out there so that you allow good airflow.
If all else fails, bring the neighbor some cookies and some ear plugs.
As others have said, get that rock outta there post haste!


Rewrite without changing URL in same domain using htaccess

Question: I have a Two URLs
NEW URL :

http://host.ip.address/nl/business/producten-en-diensten/gsm-en-smartphones/samsung-galaxy-j1-2016-zwart

OLD URL :

http://host.ip.address/nl/producten-en-diensten/gsm-en-smartphones/samsung-galaxy-j1-2016-zwart

when in request NEW URL from browser it should retrieve content from OLD URL and the URL should not change in browser.
I have tried the below rule in .htaccess it is rewriting and redirecting to the OLD URL which should not do in my case
RewriteEngine on
RewriteRule (^|.*?/)nl/business/(.*)$ /$1nl/$2 [L,R=301]

Answer: It is not possible to do a redirect and keep the original URL in the address bar." This is because a redirect, by definition, involves telling the browser to ask for the requested resource at a different URL. So the browser updates its address bar and uses the new URL.
The simplest way would be use a rewrite, not a redirect. An internal rewrite simply serves content from a local file-path that is different from the requested local URL-path.
You can use something easy like this.
RewriteEngine On
RewriteRule nl/producten-en-diensten/gsm-en-smartphones/samsung-galaxy-j1-2016-zwart nl/business/producten-en-diensten/gsm-en-smartphones/samsung-galaxy-j1-2016-zwart

You may need to also add
Options +FollowSymLinks


Strange problem with VPN

Question: I have remote VPn server, that Im trying to connect. I have password and username that are correct.
In our office we have slackware server, configured with iptables firewall. The firewall has a POSTROUTING rules, that are correct. Computers in our local network are 192.168.0. type.
Now the problem:
When Im trying to connect from my local computer 192.168.0.16, I have success, but when Im trying to connect from another one local computer (lets say 192.168.0.5), I cant connect. My username, passwords, properties, etc. are correct, and thay manage to work for one of my local computers, but not for the others.
Wild guess:From my tests, It seams, that my slackware server, remembers from witch local computer, the connection was made, and when Im trying to connect from another computer, somethings gets wrong. Reseting iptables, doesn't work, only restart of the slackware server. Then Im able to connect from another one local computer.
Also If dont restart my server, but wait for 10 minutes, It also works.
Answer: are you routing traffic through one machine to anouther, or are both machines connecting to something like a siwtch -> modem -> internet ?
It may be a routing error on the local network.
Comment: local computer -> switch -> slackware server (firewall) -> VOIP switch -> internet -> VPN server

Strange problem with VPN


What to do when I am in washroom and " Azaan" time happened?

Question: If i go to washroom after the "Sehri" and i get late in washroom and the Azaan time  happened and i haven't pray the "Sehri" Dua then what can i do? Can I pray Dua after coming out from washroom or when i am inside the washroom? please clear my problem.Thanks
Comment: What is this sehr du'a?
Comment: If you mean the niyyah that is said verbally, it has no basis in Islam.
Comment: "وَبِصَوْمِ غَدٍ نَّوَيْتُ مِنْ شَهْرِ رَمَضَانَ "     In Arabic  & In English     "I Intend to keep the fast for month of Ramadan"
Answer: There is no dua for Sehri, وَبِصَوْمِ غَدٍ نَّوَيْتُ مِنْ شَهْرِ رَمَضَانَ is not attributed to the Prophet, its source is unknown. Niyyah can be done anytime at night before the fast so do it before going to the washroom.
Answer: What you call du'a is simply a wording to declare the intention to fast. Note that in some madhhabs it is sufficient to make it once in the beginning of Ramadan (for the whole month), but basically the intention is made in the mind and doesn't need to be uttered.
Finally be aware that the wording isn't correctly translated in your comment as:

"وَبِصَوْمِ غَدٍ نَّوَيْتُ مِنْ شَهْرِ رَمَضَانَ "

should be literally translated as

And with fasting tomorrow of the month Ramadan I intended

while one should rather say something like:

I intend to fast this day of Ramadan.
  اني نويت صيام هذا اليوم من شهر رمضان

This is wrong from many perspectives: In fiqh niyyah must be uttered for an act that you are starting actually, so saying tomorrow (in Arabic غدا) you declare to fast another day as the niyyah must be uttered in the night and one rarely does suhur before midnight so it doesn't fit neither for the Islamic day which starts with maghrib nor for our 24h count. As you basically intend to fast the next day not the day that already started this should be evidence enough that this wording has no backup in the sunnah of our prophet (). Also the Arabic sentence is far away from being sound or close to what a fluent Arab would say to utter the niyyah among other issues it lacks the personal pronoun referring to oneself and an Arabic sentence starts either with a noun or verb which is not the case here.
See also

Fasting niyat(dua)
Am I allowed not to fast if I slept in and didn't make niyyah (itention)?
Can niyat (intention) be done by heart, or must it be declared verbally?
Answer: My brother it is not neccessary to pray the sehri dua but yeah it's good to pray the sehri dua. Even i dont know which dua is that but only niyyah is also better that time
Comment: Brother Dua of Sehri is this  "وَبِصَوْمِ غَدٍ نَّوَيْتُ مِنْ شَهْرِ رَمَضَانَ" and it is necessary to pray.But i am confused in that problem.
Comment: I think it's better to pray this sehri dua before going to washroom.
Answer: Brother, Islam was made easy for you, so don't complicate it and make it hard for yourself.  It says in the Quran in more than one place "I have made this religion easy for you..."
Do whatever you need to do in the bathroom.  Your intention needs to be right (Allah Knows what is in your hearts).  Like the brother said, make intention to keep a fast in your heart and mind.  Then, when you come out of the bathroom, pray Fajir Namaaz as normal.  There is nothing special about Fasting Namaaz or Dua.  You can perform any Dua in any language you like.  You make intention just before the fast begins or when it begins.  Not a day/ a week or a month before.  Our birth and death is in Allah's hands.


Insight in Buddhism

Question: What is "insight" the "knowing that I know" in Buddhism?
I understand the concept of consciousness a bit better but what about having Insight.
Comment: Hi Carlos and welcome to Buddhism SE. We have a [Guide](http://meta.buddhism.stackexchange.com/questions/1502/i-am-a-new-user-here-at-buddhism-se-what-should-i-know-before-i-post?cb=1) and a [Resource section](http://buddhism.stackexchange.com/help) for new users that you might like.
Answer: Insight is causality (4 Noble Truths, Dependent Origination and Conditional Relations) at the experiential level. Another insight what comes before this is that of the universal characteristics.
When your mind is not tainted by perversions (Vipallasa), i.e., your mind is in touch with the universal characteristics. Then you see clearly, i.e., see things as they are (Yathā Bhūta ñāna Dassana) which leads to the insight of causality. Just before this you understand the practice that brought you to the point which is the Noble 8 Fold Path which also is part of the 4 Noble Truths which is comprehended in full with insight.
At a more mundane level seeing that everything arises and passes can also be considered an insight. This is one station to realise causality and the universal characteristics.
If you means Insight Meditation by Insight this is a practice which aims at trying to understand

causality (4 Noble Truths, Dependent Origination and Conditional Relations) at the experiential level (Pativedha)
the universal characteristics at the experiential level (Pativedha)

there by verifying the theory (Pariyatti) and practice (Patipatti) through experience (Pativedha). The Insight you see that the theoretical aspects (e.g. Nirvana, causality) to be right the path which is supposed to take you to the realisation has taken you there.
Answer: There are many types of happiness and suffering around the universe. So, there are many wisdom to  gain insight about causes and effects of them (hap&suf) to avoid suffering and to take happiness.
Sīla wisdom (sammādiṭṭhi that arising with sammāvācā-magga, sammākammanta-magga, sammāācīva-magga) gain insight of physical immoral  acts by bad consciousnesses, that are causes of the worst kāma-suffering (4 apāya realms).
Samādhi wisdom (sammādiṭṭhi that arising with sammāvāyama-magga, sammāsati-magga, sammāsamādhi-magga) gain insight of kāma-consciousnesses, that are causes of the whole kāma. Because whole 11 kāma (4 apāya realms, 1 human realm, 6 kāma-heaven realms) still having physical suffering. Sīla can not protects people from abdominal pain, physical senility, angry-consciousnesses, etc. But samādhi can do. While people gain jhāna, they never feel pain, sore, or hurt. And Next life of them, bhramma-puggala, will never have any physical suffering, too. Until their jhāna's effects will be out of stock.
Vipassanā wisdom (sammādiṭṭhi that arising with sammāsaṅkappa) gain insight (3 pariññā) causes of saṅkhāra(pariññeyya)'s arising&vanishing (consciousnesses, mental factors, and matters), that are causes of life in the whole 31 realms. Samādhi can not protects people from arising and vanishing. When samādhi vanished, people can hurt again. And when jhāna's effects vanished, bhramma-puggala will die to born in the other realms such as 4 apāya, etc.
Sīla give this physical happiness to sīla-observers, people around them, and the society.
Samādhi give mental-happiness to jhāna-meditator.
Vipassanā give nibbāna (nirodha-ariyasacca), forever happiness, to arahanta. Nibbāna is no attaching (taṇhā-samudaya-ariyasacca), so nibbāna must no arising, no people, no time, no realm, no suffering (dukkha-ariyasacca).
Answer: I think that the most common way in which the word "insight" is used in Buddhism is to contrast two types of meditation: one is samadhi (concentration) and another is vipassana (insight).
The "insight" in this context is insight into the nature of things, especially the Three marks of existence.
Conversely, "knowing that I know" (which you mentioned in the question) is maybe not what's meant by insight. "Knowing that I know" reminds me a bit of Descartes' motto, i.e. "I think, therefore I am", which I think is actually to some extent opposed to a Buddhist ideal of anatta (non-self).
"Knowing that I know" might be classified as a view-of-self or identity-view (sakkāya-diṭṭhi), or perhaps it's a conceit.
I don't know, maybe it's possible for me to understand how an automobile works without being especially self-conscious about that. I'd call that understanding "insight", i.e. it's "insight into how a car works". Similarly insight in Buddhism is insight into the nature of the world, the nature of things ... I don't think it's especially/necessarily being self-conscious about that (in fact, preferably not).

Insight in Buddhism


How can I learn to recognize intervals larger than an octave?

Question: How can I learn to recognize intervals larger than an octave (compound intervals)? I recognize them in the limits of a single octave, but make mistakes when hearing larger ones. Perhaps it's because I don't know songs with them.
Answer: Another way is to learn to play chords with extensions (i.e. Cmaj9, Amin11).  The extensions go past the octave.  You should try to play the original chord, then play the extended chord.  Listen for the tonal difference and you will be simultaneously learning the intervals.  I'm suggesting this because I'm assuming that (based on your question) you can already recognize the intervals up to the octave.
Answer: You could try listening in your head to where that upper note (or lower) wants to resolve in relationship to the first note.
If say you have the interval of a perfect 11th from D4 to G5 you could think of D as your tonic (Do in moveable Do) and that G (Fa) as the fourth scale degree wanting to resolve to F# (Mi). Once you identify where the second note wants to resolve, it's just a matter of doing the theory.
If it were a major 10th where the second note (F#5) doesn't really need any resolution in D major you could just listen in your head to how many steps it needs to reach that tonic (D5).
Comment: I realize this question was posted 8 months ago but I hope this is useful to anyone
Answer: The same one trains to recognize intervals in general. Find songs that have those intervals and listen to them again again. Songs like this might be harder to find, but I'm sure there are songs like this.
Then, try finding some programs or apps for ear training and train specifically with the intervals larger than the octave. Ear Master is a program that has this feature.
Comment: Also, isolate the intervals in question. Some apps allows you just to randomize intervals above an octave; so you can get used to minor 9th - Perfect 11th for instance. Otherwise you'll be getting a lot of intervals you don't want to practice inside the octave.
Answer: Well I myself am always interested in hearing about new techniques but I think the main way is to just play two strings or two keys together over and over and develop an intuitive understanding that way.
The thing with octaves is that the farther away tones are, the less likely they are to sound like they clash.  Within an octave the relative interval is important, but beyond it is more of an open-ear'd territory.


Why Fourier transform and Stockwell-transform retain the absolute phase information of one signal?

Question: Hello friends am studying the topic of signal processing and the Fourier transform and the s-transform and in most books as for example "Time-Frequency Signal Analysis and Processing. 2nd" of Boashash in section 22.214.171.124 says that these transforms retain the absolute phase information of the signal and I do not understand that it mean with this concept about retain the absolute phase information of the signal and why this is important?.
Answer: It simply means that for a signal:
$$
x(t) = a(t) e^{j\phi(t)}
$$
that the phase information $\phi(t)$ is completely preserved in the transform
domain.
Time-frequency representations that use a quadratic form do not necessarily have this property:
$$
x(t+\tau)x^*(t-\tau) = a(t+\tau)a(t-\tau)e^{j(\phi(t+\tau) - \phi(t-\tau))}
$$
so if $\phi$ is of the form:
$$
\phi(t) = f(t) + C
$$
where $C$ is a constant, then $C$ is not preserved in $x(t+\tau)x^*(t-\tau)$.
This is important because sometimes you are interested in the absolute phase of a signal, not just its relative phase.
Comment: In maybe somewhat simpler terms. I think what Peter is saying is that the Fourier Transform is 1:1 i.e. it is invertible. Your can recover the original signal exactly and there are no ambiguities. If you just have the Power Spectrum, there are many signals that would have that exact Power Spectrum. I'm not quite sure what Peter means by relative phase in this context.


Is it safe to drink tap water in New Zealand?

Question: I'm living in a highly populated area (at least by NZ standards) in Auckland, but the question goes for the whole country.
Comment: See addition to my answer re MOH library water resources - superb - that should be reassuring :-). FWIW I and my parents family and my own family have always drunk NZ tapwater without concern throughout the country for many many many many decades, with no known ill consequences and a low level of personal & family illness.
Answer:
I'm living in a high populated area (at least for NZ's standard) in Auckland, but the question goes for the whole country.

Yes. Except in exceptional circumstances, NZ tapwater is universally safe to drink. Standards exist to ensure that major contaminating organisms such as Protozoa and Cryptosporidium are removed or reduced to safe levels.
Auckland water comes from two mains sources. West Auckland and some other parts of Auckland receive water from the Waitakere ranges catchment. Other areas receive water from the Hunua catchment and via pipeline from the Waikato river. The Waikato water is heavily contaminated at source and is treated to achieve requisite standards.
Auckland water is among the "softest" in NZ and better than most available in major cities internationally. eg whereas car batteries usually specify distilled water for topping up it is safe to use Ak tap water for this purpose.
There are variations between regions but these are mostly related to the nature of the water source. All NZ tap water is chlorinated.
About half of all NZ tapwater is fluoridated, with exceptions where local action has seen removal of fluoride from the water. Some consider fluoridation a negative measure with respect to health. The majority opinion sees it as a positive. The debate continues.

Drinking water standards for New Zealand:
The following document was found by following a series of links starting at the one provided by Mark Mayo in his answer. This is a 136 page PDF which provides extensive details.
NZ Ministry of Health - "Drinking-water Standards for New Zealand 2005 {Revised 2008} This is part of the NZ Ministry of Health online library.
NZ Ministry of Health library - water related items. A very large & useful resource:
140+ documents related to water with many of direct relevance to drinking water issues .
Only a few of the titles as a sample:

Resources for the drinking-water assistance programme - numerous papers, including:

Treatment options for small drinking-water supplies
Sustainable management of small drinking-water supplies : Optimisation of small drinking-water treatment systems
Sampling and monitoring for small drinking-water supplies
Water safety planning for small community water supplies : step-by-step risk management guidance for drinking-water supplies in small communities.

Annual report on drinking-water quality
Estimation of the burden of water-borne disease in New Zealand
International standards for drinking-water
Guidelines for drinking-water quality (World Health Organization.)
Development of drinking-water standards for New Zealand
Drinking-Water standards for New Zealand 1995
Drinking-Water standards for New Zealand
Guidelines for drinking-water quality : first addendum to third edition
Drinking water quality : problems and solutions (Gray, N. F.)
Provisional microbiological water quality guidelines for recreational and shellfish-gathering waters in New Zealand
Community water fluoridation
Cost benefit analysis of raising the quality of New Zealand networked drinking water
Draft protocols for the public health grading of drinking-water supplies
Pathogens and pathways, and small drinking-water supplies
...
And many more ......

Chlorination:
NZ water chlorination code of practice
Ministry of health notes on Protozoa and Cryptosporidium removal from tapwater

Fluoridation:
NZ Ministry of Health fluoridation page
Source Wikipedia

The use of water fluoridation first began in New Zealand in Hastings in 1954. A Commission of Inquiry was held in 1957 and then its use rapidly expanded in the mid 1960s.[96] New Zealand now has fluoridated water supplied to about half of the total population.[97] Of the six main centres only Christchurch[98] and Tauranga[99] do not to have a fluoridated water supply. In 2013 a Hamilton City Council committee voted to remove fluoride from late June 2013.[100] A referendum was held during the council elections in October 2013 with approximately 70% of voters voting for fluoride to be added back into the water supply. The mayor and most councilors have indicated that they will support the outcome of the referendum.[101] In a 2007 referendum about half of voters in the Central Otago, South Otago and the Southland Region did not want fluoridation[102] and voters in the Waitaki District were against water fluoridation for all Wards.[103] Ashburton and Greymouth also voted against fluoridation.[104]

NZ anti-fluoridation campaign
NZ national newspaper discussion on Fluoridation
USA EPA comment
_____________________________________________
Brief update September 2016:
We recently experienced "exceptional circumstances" in a small NZ town over a period of several weeks. The town supply came form bore water and was not chlorinated (to my great surprise). Contamination occurred (source when found was mentioned in the news) and several hundred people became ill, a few seriously so. It took several weeks to locate the problem wand water had to be boiled during this period. This is a very rare occurrence.
Answer: Tap water, yes, certainly.  NZ has well-defined, strict standards about drinking water.
There was a brief period of concern recently post-earthquake in Christchurch, where the aquifers and supply line got damaged, but that has since been restored.
So short answer: yes, and longer answer: yes, except sometimes immediately after unforeseen disasters.
Comment: Mark - I followed your Ministry for the environment link and after some more wandering arrived at the superb Ministry of Health library and subset it to water related papers. Too good not to add to my answer - I've noted that you provided the initial link.
Answer: I'd love to believe all the above thoughts but I have concerns. We travel all over for decades and the safety of NZ water supplies--one of the most advanced countries in the world--never would have occurred to me.  (I'm a Prof working in biomedical research at a major University).  Then reading chit chat in Tripadvisor I decided to check properly.  Bacteria (and likely viruses, due to widespread floridation) are almost certainly not issues.  However, NZ MOH standards for protozoa are "not detected" at 80% of the time.  80!!  (So one chance in 5 in getting protozoa in your tap water is the goal.  Wow.
Checking many locations( primarily rural, where we will be travelling such as Greymouth, Picton, Blenheim, Akaroa etc)  shows that they do NOT meet this low standard.  I'll skip the risk of crypto or giardia and buy some water.  Amazing!  See most recent stats for where you'll travel @ http://www.drinkingwater.esr.cri.nz/supplies/suppliescompliance.asp
Particularly for children, elderly or immunosuppressed I'd suggest caution based on what the NZ government offers.
Kudos to them for being transparent and helpful. Buyer beware.
Comment: You've picked some relatively small communities, although I'll admit I was surprised by Blenheim.  However most big cities (I checked a couple like Christchurch) certainly meet the standards.
Answer: No. i work in this area. There are standards but they are rarely enforced. Unless you are in a major city you should boil the tap water. Esp if you are in a rural area you definately should boil before consumption, using to clean teeth, wash salads or make ice. This also applies to many food places and wineries as they are on their own supplies and untreated. Tap water here is third world except in major cities.
But Blenheim is fully compliant now.


berkeley db debian wheezy

Question: I am trying to make a website that supports bitcoin, but I cant install bitcoin core because berkeleydb is under 4.8. I tried installing it via apt-get squeeze repository but that didn't work. I also downloaded the tar.gz file and installed that but that also didn't work. Does anyone know how I can install berkeleydb or what linux distro has full support of berkeleydb?
Answer: Here is good guide (read comments too)
https://www.howtoforge.com/tutorial/how-to-compile-and-install-bitcoin-core-on-debian-wheezy/
also you can use bdb 5.1 (./configure --with-incompatible-bdb) if you don't have a plan to move bitcoin data to/from other computer
Comment: @Nick Yes, a wallet.dat touched by bdb 5.1 won't be readable by a bdb 4.8 version. However, it's trivial to convert it back if needed (db5.1_dump wallet51.dat | db4.8_load wallet48.dat)
Comment: I strongly suggest that you not use an incompatible bdb. The time it costs you later is *not worth* the time you save.
Comment: @NickODell, isn't incompatible bdb just for compatibility with older wallets? Why would you need compatibility with older wallets if you're starting a new wallet from scratch?
Comment: @StephenM347 I was under the impression that later versions like 5.1 weren't compatible with bdb 4.8, meaning that the wallet you created using bdb 5.1 instructions wouldn't be compatible with a bitcoin core client built using bdb 4.8. That's probably worth a question of its own, though. http://bitcoin.stackexchange.com/questions/42965/do-berkley-db-versions-need-to-be-the-same

berkeley db debian wheezy


AMPScript for Dynamic Content

Question: I want to start out by saying I am new to AMPScript though I have a lot of programming/scripting experience.  I am trying to figure out a way to do the following.I have a customer who has multiple (could be any number) products associated with them.  Right now I receive a delimited file that list give a user id and then all the product fields delimited by a "|".  If a customer has more than one product associated with them there will be a separate line in the file for each product. What I need to do is to import this file into ExactTarget and then generate an email for each customer based on this data.  Most of this is pretty easy besides the multiple products.  I was hoping some guidance could be provided on using AMPScript in a template to generate a chunk of HTML for each product that is associated to the customer (this will vary per customer).
Comment: Any input would be greatly appreciated.
Comment: @Adam Springs Did you get any solution for this issue. I am looking into the same issue as we have multiple line items in an Order and we are importing those orders through data extension and not sure how to handle the multiple lines in email.
Comment: My answer below outlines it.
Answer: If you imported this Product data into a Product Data Extension, and you're sending to another Data Extension that's related by User_id, then you can simply use one of the AMPScript lookup functions to output the data in the email.
Something like this:
%%[
var @rows, @row, @rowCount, @numRowsToReturn, @UserId, @i

set @UserId = AttributeValue("user id")
set @numRowsToReturn = 0 /* 0 means all */
set @rows = LookupOrderedRows("Products",@numRowsToReturn,"SKU desc, qty asc","user id", @UserId)
set @rowCount = rowcount(@rows)

if @rowCount > 0 then

for @i = 1 to @rowCount do

    var @SKU, @qty
    set @row = row(@rows,@i) /*get row based on loop counter */
    set @SKU = field(@row,"SKU")
    set @qty = field(@row,"qty")

]%%

Row %%=v(@i)=%%, SKU: %%=v(@SKU)=%%, Qty: %%=v(@qty)=%%

%%[

next @i ]%%

%%[ else ]%%

No products found

%%[ endif ]%%

Reference

LookupOrderedRows()
Answer: Checkout this document, specifically page 127: http://memberlandingpages.com/docs/AMPscript_Guide.pdf
It shows a nice of example of looping through data from a data extension, which sounds like what you're wanting to do with order/product data.

AMPScript for Dynamic Content