What are good tips for remaining composed during one's first public performance?

Question: One's first public performance can be daunting in terms of the amount of anxiety involved. How should first time performers who have never been on stage (or performed in front of unknown people) deal with this? What are some good tips that seasoned performers use?
Comment: Always remember that people's lives are permeated by reproduced music nowadays. They hear it in shops, elevators, television programs and commercials, from passing cars. People have learned to tune it out. Many of those listening just want to hear a live instrument make some noise. It may help you to spend time looking at some completely lousy YouTube videos that have glowing comments below them like, "wow, you are great; I wish I could do that". No matter how badly you screw up, you will be an inspiration to *someone* in the audience, unless it's entirely pro musicians.
Answer: The best thing you can do is to know your stuff.
Practice it well beforehand, and know your material very well. This way you can get into the groove and stay there (and not be thinking about how sweaty your palms are, or how you're certain the folks in the back row can see your limbs trembling from fear) and then the next thing you know will be along the lines of "oh, I'm done, and lightning didn't strike me dead."
Public speaking is another type of performing in front of others that takes a lot less practice than performing a recital. With the same fears, panic and stress. Acting classes, or Toastmasters can alleviate some of the fears of being in front of crowds. Since most office workers will need to stand up in front of groups and give presentations (or at least argue your point), they are skills you will have to know anyway. With the confidence of a couple of talks or improv sessions, you should be able to recognize that you can do it and go through more difficult or challenging situations. This is part of why "boot camp" in the military is so stressful - you learn to feel the fear and do it anyway. Then, when you are in actual combat, you've already been scared to death, but you know you can do what has to be done.
Answer: Don't rush.  If you have seen a lot of live performances you know that professionals don't run in, sit down and start playing immediately.  Take your time; sit or stand comfortably and check the instrument and the music to make sure everything is ready.
Remember that the audience is not full of critics and music teachers.  It's full of people who are there to enjoy the music. If you make a mistake, don't let on.  Keep going.  Believe it or not, most people won't even notice the mistake.  If you have a memory lapse, don't go back but instead skip forward in the piece.
Best advice anyone gave me:  If you're playing a recital, get the whole thing ready to play ONE MONTH before the actual performance date, and then keep practicing every day.
Comment: "_Remember that the audience is not full of critics and music teachers_" - excellent advice. Most people won't be capable of doing what you do - even if you make a few slip-ups and carry on, they'll still come away impressed by your performance. Even the most amateur magician can appear impressive when you don't know how he does his tricks!
Comment: I have a live performance of Erroll Garner where he just comes in, sits down and begins to play. But generally I agree with what you're saying, I just thought it was a nice anecdote :)
Answer: I agree with what Tangurena and Mark Lutton wrote, but would like to add some thoughts. I've been playing the piano since I was nine and had a lot of half-formal performances (so mostly in front of other music school pupils and their family) during the ten or eleven years that I've had music lessons.
I'm generally someone who likes being on stage, so I never really minded playing in front of other people.
One thing I will always tell people is that there's basically nothing that can go wrong. Yeah, you might forget the words or might mess up that part of the piece or forget where you are and start over or something. That might happen. But even if it does...
a) You won't die. Nobody will die. Nothing considerably bad will happen just because you didn't get that one little part right.
b) 99% of the time the people listening to you are already giving you credit for going up on a stage and performing for them. So, they will forgive. They already think what you're doing is cool and brave and they don't care if it's not perfect. Chances are you're already showing them something that they can't do but wish they could.
c) If you don't let it on too much or really have to start over again, people won't even notice when you mess up. I've had performances where I totally forgot the words and started a song over again from the start and people forgot that that happened by the end of the song. Either just be cool with it and say so ("Sorry, but I messed up. Have to start over, but this time I'll get it right") or - if you can - just keep on playing.
This sounds a bit pessimistic as I'm actually referring to how to deal with failure, but this is actually meant as encouragement. The best advice always is "Know your stuff". Practice. But if you're still nervous and unsure, understand that failure on stage is not the end of the world. It hardly ever actually is failure after all. If you can remember that, you're more likely to be calm and cool on stage and less likely to actually forget anything.
Comment: The one thing that I would add that may be helpful is to record yourself. This will let you hear yourself as others would hear you.
Answer: Your first performance should not be your First Performance
Tangurena really summed it up well with "know your stuff." With that in mind, remember that playing your piece is the very last part of a performance — the culmination of everything that came before. So make sure you're really solid on that stuff, too.
Consider all the things that happen before you play the piece. Here's a rough list of the lead-up to the first note, working backwards in time.
10: Take up your instrument (including, say, sitting down at the piano)
9: Greet the audience (perhaps with a bow)
8: Walk on stage
7: Wait backstage for the signal to walk on stage
6: Sit backstage/off-stage
5: Arrive at the venue
4: Leave home for the venue
3: Prepare to leave home for the venue (could include dressing, eating, paying your light bill so you're not thinking about it during the concert, ...)
2: Sleep as well as you can manage
1: Practice arduously
Not only is playing the piece is the last step, but it's not really clear where the first step was. When you walked on stage? When you prepared to walk on stage? When you left home? ... When you played your instrument for the very first time? The performance is just one point on a continuum that started well before and will continue after (finish the piece, bow, leave the stage, go home, practice more, ...).
So practice/rehearse all of these other aspects as well. Travel to the venue a few times, so you know how to get there and how long it takes. Eat before playing through your program at home so you have a sense of how much or how little to eat before your performance. Try on outfits; try performing in them. When you practice each day, walk to the piano as though walking on stage. Take a bow before you begin and when you finish. Etc., etc., etc.
And, not least of all, before you perform for 50 people at a venue, perform for 5 people at home. And before that perform for 1 person. And before that, perform for inanimate objects. Start in a way you can be comfortable and work up from there as you feel ready. Perform for yourself with no one home and the doors and windows locked and the blinds closed and with the radio turned up so no one else can hear you.
To sum up: practice being comfortable (with all parts of) performing. If you only force yourself into uncomfortable situations, then all you're practicing is how to make yourself uncomfortable.
Answer: Do another performance. Distract yourself from the 1st, 2nd, 3rd...
It is always possible getting better. Think of yourself as an eternal beta version. Nobody is ready and will never be. Just get what you have today, do it and improve.
Enjoy the ride.


Is my newly planted weeping willow in shock?

Question: This spring, I planted a weeping willow tree (salix x) in my yard, in an attempt to help dry things out. I'd heard they love wet conditions, and can grow up to 8' a year. Well, it has been almost two months, and my tree has not grown. It has turned yellow and developed dead areas on the leaves and stem-tips. My first thought is, maybe it was too much of a shock to move straight from the 16" nursery pot into the saturated soil in my yard. The tree was a little over 6' tall. Is this the problem? How can I relieve the shock?
Comment: Check out Willow anthracnose (caused by Marssonina salicicola) particularly if you have blackish, small cankers showing on the stems as well, just in case it's that
Comment: will the area still be wet after those handsome drainage pipes are installed?
Comment: @Bamboo Thanks for the reply. I can't find any cankers of any size along the stems/trunk. Do they sometimes come after the other symptoms?
Comment: @kevinsky those pipes are actually going to drain the large puddle/marsh on the other side of the driveway to the right of the topsoil pile. They will drain it directly into the ditch by the road on this side, where the township already has an 18" pipe draining to the other side of the road. I don't know if that will help this side much, but the ditch by the road will be deeper than before.
Comment: @jmusser - yea, sometimes it starts with black bits here and there, and left long enough, they become bigger black lesions and develop into cankers. This infection can be a problem in very damp ground.
Answer: Apparently, it was transplant shock caused by the big change in soil moisture content. The ground has now dried partly (still very damp, but not saturated in the top 4 inches anymore). As soon as that happened, the tree grew quickly (4-10 inches, in different areas), and the new growth doesn't show dead tips/leaf spots. It also has increased leaf size, and is a couple shades darker green.
Trees should ideally not be planted directly into saturated soil. Trees that can grow in these conditions should be adjusted slowly, sort of like hardening off. (And I know the tree should be staked. I'll get around to it. The stake in the question was placed there by the kids, and was removed for girdling reasons.)
See pictures:
Answer: They need moist soil down 2" if saturated below that you need to check roots, they will stop drawing water if saturated.  Give the roots exposure to air a day or two to dry them cover with soil they should start drawing water again, have your soil tested for salt... nutrients. One more thing is to check under the leaves for insects.  Hope it helps.


Is my 'question seeding' appropriate?

Question: As you all may have noticed, I am 'seeding' the site with a bunch of questions. If anyone thinks it inappropriate, please let me know.
Answer: I wrote blog post addressing the issues of seeding and asking the first questions on a new site:
Asking the First Questions
Comment: For those too lazy to click, the answer is "No, you should not seed on Area 51 sites.   They get all the momentum they need via the vote/beta format."  And I think we see that here - there's more than enough activity already without adding fake activity.
Comment: Fair enough. If there isn't enough momentum without seeding, there isn't enough momentum to sustain the site without it afterwards either.
Comment: @Tobiasopdenbrouw: That is very true. I've seen many attempts by [SE 1.0](http://blog.stackoverflow.com/2010/04/changes-to-stack-exchange/) sites to artificially "simulate" different types of activity. It was *unsustainable* each time and didn't work.
Comment: Ah, that's an excellent blog post.
Answer: I'm good with it, although I hope someone does the same for some other games. I badly don't want us to get too D&D 4e-centric. Commented on one of the build questions with a minor concern.
Comment: It's just that 4e is my 'borderline to get into' system. You'll note my other pets are universalis and shadowrun. But there's much much much more out there.
Answer: Actually, I'll add a separate point - I just noticed all your questions are community wiki instead.  I think this is totally the wrong use of CW.  In my view, CW should be generally "smaller", made up of high value FAQs and lists.  Spitting out random questions and just marking them CW is bad - I assume it's to not be rep-whoring, which is good, but in that case probably not posting them is better.  Our CW is already by this point a big mix of unrelated junk that at first view doesn't look different from the main site!!!
More followup in the "what should we use CW for" question but I thought I'd note it here.
Comment: It's neither random (I am genuinely interested in the answers) nor rep-whoring. As to the CW: I've not been doing so in 'regular RPG', but I may have been doing so in meta too much.
Comment: Link to [How should we use Community Wiki?](http://meta.rpg.stackexchange.com/questions/59/how-should-we-use-community-wiki/87)
Answer: I think at this point, while we are in private beta, it seems okay, since it's important for us to build up a question base.  If someone were seeding later with questions that they didn't necessarily actually need answers to, that might be different.
Answer: Maybe for this beta, maybe, but I think we shouldn't seed too much.  Questions should be honest questions.  I know I personally don't feel like answering un-genuine questions, because I have other priorities than snapping up rep.  And part of the point is to see what happens organically, what questions are really FAQs and not just someone thinking they're being clever.
I'd vote "only ask legit questions."
And on the 4e thing - yeah, I don't want to see this get too 4e-ey either, and I'll note that some of your questions like "Int vs Wis" would be better scoped to all D&D or even wider than just 4.0 - if I had a way to "ignore all posts tagged dd4.0" I'd be planning to enable it soon, as there's a lot of stuff on it and I don't play it.

Is my 'question seeding' appropriate?


How do you deploy your ESX servers?

Question: There are a number of ways to deploy/install ESX; RDP/PXE, from CD, remote ISO boot etc.
What's your favourite method and why?
Comment: How many do you need to deploy? (I have to ask, professional curiosity/envy.)
Comment: Oh we do a few hundred a year via HP RDP but I'm interested in others situations.
Answer: kickstart with pxe. That's also the direction you'll get directed to in their training courses. For the install it's little more than a redhat install with some extras, so kickstart is the way to do it. This makes more sense when you're building a cluster and want identical installs.
Comment: Absolutely kickstart and PXE is the way to go. For extra convenience use the VMware Deployment Appliance. Drop it into a VMware Workstation or another ESX host if you have one, test a few builds, tweak the scripts and then roll out to as many ESX servers as you need. In addition to getting a higher level of consistency in your V3.5 configs you also have a reliable easy rebuild process.

It's possibly not worth the effort when you're only building a handful but if you're setting up any decent size of cluster it will save you a lot of repetitive, error-prone, manual configuration.
Answer: One at a time. From CD.
I like this method, because the only person I can blame is myself. I have an install document that was created when the first server was deployed. Do it once, double check, do it right.
Of course ... I only have 4.
Scaling beyond this mere handful, I would probably start with PXE. Deploying over the network is much easier and reliable than doing it by hand.
Comment: I'm not going to vote you down, but structured is almost always better than by-hand. People make mistakes. Scripts make mistakes reliably ;-)
Comment: I'd argue that it's worth creating a scripted install even for one server.  It makes sense to me to distil knowledge into scripts - that one server may need reinstalling one day.
Comment: People do make mistakes, that's why there's documentation ... is it really worth creating a scripted install for < 5 servers?
Comment: That being said ... I just upvoted the kickstart answer.
Answer: I have a couple of basic system images (VM disks) which I clone as necessary to create new VMs.  I keep these base images up to date by firing them up every once in a while and getting patches.  I've done cloning both by using the VMWare vCenter Converter and just copying the raw files into a new directory and updating the .vmx files.  Turn on the clone, rename the host and update the IP, and I've got a ready-to-go brand new server.  I have about a dozen VMs running on two servers right now using this method.
Answer: Being that it takes about as much time to install ESX as it takes to take the server out of the box, I go CD.
99% of the time when you need to install ESX you're standing beside the physical machine anyway. Pop the CD in and go and skip the network drama.
Answer: We prefer to SAN boot ESX servers in our environment whenever possible.  Instant clones and snapshots make each ESX server very easy to deploy and back-up / migrate.  Obviously there are additional costs involved, since an HBA (FC or iSCSI) is required - or you can use an unsupported software solution like the iSCSI software initiator or gPXE.  In the cases where we use local disk, the PXE / Kickstart method works great.
Answer: Depends on where the servers live.
As with most everyone else, PXE booting/install is by far my first choice (and is absolutely trivial with ESXi).
In some cases, PXE booting is not appropriate or available (think secure DMZ's).  In this case, installing using the server's out-of-band Lights Out Management CD redirection functionality means I can do it from my desk without hanging out in the datacenter or needing to reconfigure one of the host's switch ports to a more netboot-friendly network.
As for host configuration, configuration can be scripted using the v(I)MA toolkit or virtual appliance, although these tools have some functional limitations.  vSphere (ESX4) makes this even easier if you have licenses which include the Host Profiles functionality (configure one host correctly, define it as your host profile configuration source, apply config to all other hosts in the cluster. It will check daily to make sure the hosts are still compliant with their "golden" configuration).
Note that not all configuration can be scripted via v(I)MA or be managed under Host Profiles; some manual processes are required to complete host configuration due to some configuration options not being available through these tools.  In this case, a written procedure or checklist will ensure you don't miss anything.

How do you deploy your ESX servers?


Command Line Tools Difference?

Question: Is there a difference between the command line tools that come with xcode and the ones installed with xcode-select? If I install xcode and then run xcode-select --install will the ones installed with xcode be overwritten?
Answer: Xcode has command line tools embedded in its application bundle that are used by the Xcode IDE as needed and are separate and apart from the Command Line Tools for Xcode package, that can be downloaded by itself, which installs outside of the application bundle. The separate package can be installed and use without having the Xcode application installed.  As to versioning, I believe as each version of Xcode is available a corresponding version of the Command Line Tools for Xcode package is also made available and for what's included in common should be the same versions.  When installing the Command Line Tools for Xcode package with Xcode installed it does not overwrite the Xcode.app bundled command line tools, they are updated as Xcode is.
Answer: If I recall correctly it downloads the xcode tools command line package, which is part of the main xcode distribution. I wouldn't expect it to download anything at all if the command line tools are already installed.

Command Line Tools Difference?


Consumer rights when a refund is not processed correctly

Question: Recently, I have experienced the following sequence of events:

I purchased an item from a major Australian retailer "A".
I found the same item cheaper at a different retailer "B".
Retailer A was unwilling to match retailer B's price. However, they do offer a no-questions-asked change-of-mind returns policy. As such, I placed an order with retailer B, and returned the original item to retailer A, who accepted the return and provided a full refund.
The order with retailer B was cancelled on their end due to insufficient stock.
I returned to retailer A to place a new order for the item (at their higher price). They accepted the order, charging a non-refundable deposit.
Reviewing my bank statements, I discovered that the "refund" from retailer A actually resulted in a debit to my account, rather than a credit of the refunded amount.
Retailer B found additional stock of the item, and honoured my original order with them.

As a result of this saga, I now have two copies of the item (one from B, and one on order from A at a higher price). I've essentially paid A three times for the one item, and I don't even need it anymore since I got it cheaper from B.
Who legally owns the item purchased in step 1? Since it was returned in expectation of monetary compensation, I'd argue that the transaction with retailer A in step 3 didn't actually transfer ownership back to them, since that compensation didn't occur. However, I imagine that they could argue they own the item, since they have physical possession of it and (as far as I know) their computer system shows the original transaction has been reversed.
The reason this is relevant is because I wish to cancel my order with retailer A without financial penalty, including a refund of the "non-refundable" deposit. I'd argue that the order was placed under the mistaken belief that I no longer owned the item purchased in step 1, and never would have been placed had I known I still owned the item. Since that mistaken belief was a result of their mistake processing the earlier return, I believe it is their responsibility to correct the situation with no financial detriment to myself.
I ask this question now, before having discussed the situation with retailer A. I fully expect them to completely refund the transactions of steps 1 (as originally agreed) and 3 (to correct their mistake), however I'd like to be able to mount a solid argument for requesting a full refund of the transaction in step 5.
Is my understanding of the situation correct? Am I likely to be able to argue my case as described above? Are such situations covered under Australian consumer law, or will I have to rely on good will on retailer A's part?

NOTE: I have receipts, invoices and bank statements attesting to each of the transactions involved, which I can provide to retailer A to prove my case if necessary.
Answer: Ownership of the original item passed back to them when you and they agreed to the return. Possession of and risk of loss or damage to are different questions to ownership.
The fact that the refund has not yet been properly made is irrelevant. At this point, they owe you money, they do not owe you the item.
Non-refundable deposits are legal in Australia but the maximum amount depends on state law and the type and value of the goods or services.


High Beam Indicator Problem

Question: I have a situation where I'm doing wiring for the dashboard of a vehicle. For whatever reason, the turn signal/headlight switch on this vehicle outputs a 6 volt signal on the high beam wire when the low beam is on and a 12 volt signal when the high beam is on. The headlights work as they're supposed to, but the high beam indicator led is activated when the low beam is on since 6 volts is enough to activate it. Does anyone have a simple solution to make the indicator only turn on when there is a 12 volt signal and not when it's a 6 volt signal?
Comment: What kind of vehicle is "this vehicle"
Comment: That happened to me when I changed the old classic H4 bulb with the LED one. I haven't checked voltage (yet) but it seems that high beam connector gets 6V when low beam is connected to 12V since high beam indicator (which is connected to high beam bulb connector) lights with half power when low beam is turned on.
Answer: I'll expand on one of cinelli's comments - why not fix the cause rather than the symptom? If you've got 6v on the high-beam feed when the switch is set to dip, this suggests to me there is a problem with the switch - and I'd be worried that it might be causing other hidden problems.
For example, if the lamps aren't relayed (as is the case with a lot of older vehicles), you'll have 6v running through the high-beam filaments all the time the lights are on. This won't be enough to light them, but will shorten the life of the bulbs...
Have you tried another switch?
Comment: Got my approval +1
Answer: Try putting a 6v2 zener (400mW) diode in series with the indicator LED. The LED takes about 1.5V so nothing under 7.7V should be able to turn it on. The LED current should be small enough to use a low power zener diode. Make sure you get the diode the right way around.
Comment: Though your solution may answer the OP's question, the real problem that needs to be solved is why is there 6 volts on a wire that shouldn't be there.  We need more info to handle that.
Comment: @Mobius - That was not asked for in the OP's question. I have simply answered the question that was asked as per the guidance on answering questions. Perhaps the OP should ask another question - 'why do I have 6V etc..." and deal with it there.
Answer: If this is a simple logic chip that is detecting it, then you won't need a lot of current to trigger. In that case, just put something like two 1K resistors in series to ground and divide the voltage in half (the old output will now be in between the two resistors).
Answer: The indicator lamp on some vehicles is also illuminated if the resistance in the wiring is not equal to a certain amount. This is usually cause by using an incorrect bulb (even though the bulb will still plug in and work), If one of the connectors is corrodded etc. A little more details on the year make and model of the vehicle would be helpful. Finding and fixing whatever is wrong sounds a lot less of a hassle then soldering a diode in line to "mickey mouse" the fix.
Answer: I had to figure out where the 6V came from so I drew 2 lamps side by side and gave each a ground connection. I provided them both with 12V to establish 2 lamps in paralell. I then misconnected one of the grounds to 12v and realized 6V on the supply side of the lamps. Poor boy got his wires crossed.

High Beam Indicator Problem


Isolate a subwoofer from the floor below

Question: So, I live in a two story house, and I have a subwoofer. any recomendations to isolate my subwoofer from my floor to keep the room below me relatively quiet?
Answer: How much money have you got to spend & would you consider replacing the floor entirely with a new one made of solid concrete, not connected to the current walls or floor?
That is not as frivolous a question as it may seem.
Audio separation, especially at low frequencies, can only be achieved by mass & air-gapping.
You could generate a bit of an air-gap by getting the sub off the floor. Whether you rest it on egg boxes or hang it from the ceiling is only a matter of scale.
Bear in mind that not only the floor, but also the walls, will transmit sound downwards to your neighbours.
Recording & broadcast studios spend $£€ 50... 100,000  truly shaping & isolating sound.
Realistically, even with the sub a metre off the floor, unless the floor itself is solid concrete a metre thick & you also float an entire room inside a room built of dense material & also isolated from the floor & walls, then forget it.
Practically, the only solution available to most people of average income in a shared building is...
Turn it down.
I once spent several thousand pounds trying to achieve similar separation for a home studio; so I did my research & built a competent isolated room structure inside the existing room,  but couldn't afford [of course] to replace the wooden floors with concrete.
The room I ended up with was in a basement & was quiet as a grave from down there. In the rest of the building, however, I could 'name that tune' from just the bassline I could still hear from the 3rd floor.
Comment: Ok, I will try seperation.
Comment: @pcs3rd maybe sell that subwoofer and buy a pair of speakers with sufficient bass, that will actually sit higher and be more directional. Subwoofers often sit on the floor which makes it even worse.. The separation is going to give you next to nothing as Tetsujin states. You can get far better quality and consistency by using speakers with sufficient bass, rather than a suspended/turned down subwoofer.. just my 2c as an alternative proposal based on this answer.
Answer: A subwoofer is primarily responsible for the reproduction and/or production of frequencies you do not as much hear as you feel them.  You feel them by their effect on masses like your body.  The wavelengths are comparatively long, so unless we are talking about a hall, most of the sound/wave propagation will be by pressure.  The only way you can not transfer pressure is by receiving it in mass and dispersing/diverting it.
That involves measures that have significant mass and cover the majority of the floor, meaning measures requiring the approval of structural engineers.
How much is that subwoofer sound worth to you?


Will removing my account remove all the posts I created while using the site?

Question: Is it possible to delete your account and automatically remove all your posts, or when you remove your account do your questions/answers remain on the site?
Comment: Don't quit over flash sucking. It sucks for everyone no matter where you post on the internet!
Comment: "it makes me slightly uncomfortable that community members and mods can edit posts that are attributed to me as author." This is an essential part of how SE works - as someone who participates on SO,  You *need* to know this - its an essential part of how the site works. I've had a few edits that seriously improved my answer in the past, so really, this works both ways
Comment: Don't commit Internet seppuku! If things get too stressful, just give yourself a personal timeout from the site, relax, and come back in a week with a fresh perspective. Plus, other folks could benefit from your questions and answers even if you do decide to leave. Do you really need to go nuclear?
Comment: Drama, drama, drama... Over edits??? Why is this necessary? Also, you are a member for more than a year, you know how to search around the site I assume, search on meta for remove account?
Comment: Wim, rather than just getting up and leaving, do you care to explain some of your issues and see if they can be resolved? I'm personally not aware of any edit wars, though we have had and will always have drama. Ubuntuforums is vastly different from this site, of course, and we are not for everyone, but if you don't understand how the site works, that is what would lead to the conclusion you've reached.
Comment: That's a good point that future readers can benefit from existing answers on my questions, which other users have put time and effort into adding.  But if I remove my account, will my posts be attributed to me or to some "user12345678"?  I use my real name on here and it makes me slightly uncomfortable that community members and mods can edit posts that are attributed to me as author.

I intend to continue to participate on stackoverflow.com, if that changes any technical details..
Comment: At any rate, this is related: http://meta.stackexchange.com/questions/5999/how-can-i-delete-my-account
Comment: @RolandiXor OK, I can elaborate in [chat](http://chat.stackexchange.com/rooms/9004/http-meta-askubuntu-com-q-6774-21350).
Comment: @JourneymanGeek I agree, the vast majority of edits on my posts are really helpful and useful, usually it's some better way to do something that I didn't know about or some detail I forgot.  The occasional annoying user is the exception to the rule here.
Comment: BTW, if anyone wants to edit the answer bellow and improve it / fix formatting and wording, maybe add a link or two to the duplicates about this subject, feel free to do so. Wont be upset about it...
Comment: @BrunoPereira yes, but I couldn't find an authoritative source on what happens to your existing posts after removing account.  I've found one now.  p.s. edit button is greyed out on meta
Answer: Your question is blossoming into five or six separate questions. I will attempt to run over most of them quickly:

You can delete your account but your posts stay.
Your posts will be attributed to deleted version of your user. This may keep your name, it may be attributed a user1234566 account. Probably the second (I think it's only cross-site question migrations that used to throw the name over).
Editing is an essential part to maintaining a system like this. People go missing and abandon things. This way everybody can maintain everything and that's not going to change.
Edited posts have a revision history that anybody can see. They're not putting words in your mouth, they're putting words in your post and people can see evidence of that.
Getting upset with a system and wanting to leave is not a phenomenon unique to us, or even the Internet. You see it in most mammal communities and it has been an essential part of genetic and societal development for hundreds of thousands of years.
That said, we want a happy community here and we try help that end by being completely open from the offset. If the community and the moderators fail you, there are also people at Stack Exchange you can talk to... But none of that will ever stop people becoming disenfranchised. We could dip into this well but you've already said you've little interest in the psychology of things.
If you have a specific grievance, we want to know about it. This is particularly relevant to me because I was the person who dealt with one of your questions yesterday.
Comment: Also, "Content you've posted on the site is owned by you but licensed to Stack Exchange, and you therefore cannot request that it be deleted with your account." (Per http://meta.stackexchange.com/questions/5999/how-can-i-delete-my-account ).
Answer: You can ask Stack Exchange to erase your account following the methods posted on all the previously asked question in meta about the same subject.

No, the posts that you created with your account are property of the Ask Ubuntu and the Stack Exchange network, even if you ask them to be deleted or removed when your account is, they will not and you cannot do it just because you want to. Their content is part of the site when you create them and will not be removed when your account is.

This all question is a dupe of many others around the site, the reasons are always the same... Drama, user feels that he is not appreciated or targeted by evil cat like creatures and wants to leave and remove his account and destroy his/her contributions.
From what I understand this is over edits? Really? Look, take some time for yourself, go for a walk and enjoy the sun, come back when you want to (or not, no one forces anyone to be around, ever). There are many more things to worry about in life; edits on a website that allows and stimulates them is not one of the things that would make me wake up in the middle of the night.
If after you walk you still feel upset about anything then just ask the Stack Exchange community to remove your account, it's fine, but your posts stay.
Comment: Hum, I did not say that there were many people asking to get erased, only the reasons are most of the times similar (loss of rep because of misuse of accounts, upset because of edits over one reason or another - edits are part of the site! -, upset because someone down-voted or *whatnot* of of the user's posts, and so on...), a small difference there that invalidates your argument that something is actually wrong.
Comment: Look, we value all contributions to the site, edits are part of it, unless we have a consensus that there was abuse or invalid edits target at you there is not much we will do, if you feel you want your account removed then that is a pity, but life goes on. Let us know what you really want to do, my advice for some time out and come back again later with a calmer head still is the best one I can give you.
Comment: If it is a dupe of many on the site and the reason is always the same, drama, etc then that suggests to me there is a real problem with the system because it is something that is happening regularly.  It shouldn't happen at all.  But I assure you I am not losing sleep over this :)
Comment: @maggotbrain I removed you comment cause it broke my comments, sorry for that.
Comment: Thanks Bruno.  But I am not asking for a psychologist here, I just wanted to know what happens to by posts when I remove account.  They remain but become anonymous, and I'm happy with that.  Cheers
Comment: @wim I'll be quiet then (where Is should have never left), cheers and take care.


Should I use math notation in a patent application in light of Alice decision.

Question: I use some math notation in my software/method patent application to make the description precise. I am not claiming any mathematical operations. Could it be that just the usage of math notations causes application rejection?
Answer: You need to hire a patent lawyer to answer this question.  Making that all the more annoying, even the best patent lawyers are just guessing at how Alice will be implemented going forward.  For my own inventions, if I have code, formulas, etc., that are helpful to others understanding the invention, I include them.  Even before Alice, you couldn't claim laws of nature, so I don't know that Alice really changes things in this aspect.  But until the implications of Alice shake out -- and until the Supreme Court lets patent law kind of settle down before taking new cases -- well, talk to a patent lawyer.
Answer: IMHO the answer is No*.  The way a method is described should not effect whether it is simply a digitization of an "abstract idea" or not.
*But it is possible that the use of math notation will make it seem more like and abstract idea, and that could draw attention to it if it were a borderline case.
I agree that consulting a patent lawyer about this may be a good idea, but I would personally focus primarily on adding language that highlights reasons why your patent is more than just a digitization of an abstract concept.
The main advantage gained by avoiding math notation would be a potentially increased probability of a weak patent flying under the radar, and the value of this stealth would depend on the costs and risks of utilizing the weak patent.  If the patented software or method is easy to implement this could actually add significant value, especially if it would be produced/used even without the patent. But adding stealth to a weak patent would add little to no value if implementing the requires a major financial investment that could not be recouped if the patent were invalidated.
Comment: I don't want a weak patent. I want potential investors be assured that the business is protected. Also I hope to use a patent as a marketing tool, so people familiar with the field can appreciate its value.


what is arduino adc reference?

Question: I'm using arduino for the first time and don't really understand what am I suppose to plug to the ADC refernce PIN... or if I even have to use it while plugging analog sensor to the arduino,
thanks!
Comment: Does https://www.arduino.cc/reference/en/language/functions/analog-io/analogreference/ help? You don't have to use it.
Answer: The AD converter in the ATMega microcontroller (as used in Arduino) converts an input voltage to a number.
This ADC happens to be 10 bit that means 2^10 states which is 1024.
The number 0 (zero) means 0 Volt input voltage.
The number 1023 means the maximum input voltage.
Since 0 is also a value the scale runs from 0 to 1023 making 1024 values.
The scale is linear so 511 means half of that maximum voltage.
What is this maximum input voltage?
That is the ADC Reference voltage. By default the power supply voltage is used so if you run your Arduino on 5 V, then 1023 = 5 V. But if you run your Arduino on 3.3 V, then 1023 = 3.3 V.
There is also in internal reference of 2.56 V (or 1.1 V depending on your Arduino), if you use that then, you guessed it, 1023 = 2.56 V (or 1.1V).
You might have a very fancy external reference voltage already available and if you want to use that, use the external setting and connect that reference voltage to the AREF pin.
If your analog sensor gives 0 to 5 V and your Arduino is also powered by 5 V then you should use the default setting so that the VCC is used as ADC reference.
If your sensor gives a voltage between 0 and 1 V then you could use the internal reference so that more of the 0 to 1023 range is usable. Giving you get better resolution.
Answer: The default behaviour is for the analog reference to be Vcc which on many Arduinos is 5V. In that case do not connect anything to AREF.
However if you have a precision voltage reference then you can connect that to AREF (and GND) and specify in your sketch, before doing an analogRead:
<code> analogReference (EXTERNAL);
</code>
I have a page about the ADC converter which may help explain, or may be too much detail. :)

or if I even have to use it while plugging analog sensor to the arduino

Unless you are planning to use some different reference voltage, don't use it at all.
For a 5V Arduino the voltage measured with the default AREF would roughly be 4.88 mV per unit of measurement (ie. 5V / 1024), but more accurately:
<code>float voltage = ((float) rawADC  + 0.5 ) / 1024.0 * Vref;
</code>

The voltage you supply to VREF (if you supply any at all) must be between 1.0V and Vcc where Vcc would be 5V for an Arduino Uno.
Comment: "_do not_ connect anything to AREF" and "[call `analogReference(EXTERNAL)`] **before** doing an analogRead" (amphasis mine). These are _very important_ points not mentioned in the other answers.
Comment: I added the emphasis in my answer in case it was too mild as it was. ;)
Answer: The AREF is a reference voltage input pin.
The reference voltage is maximum voltage when you measure analog signal.
In other words, you can measure 0V ~ AREF voltage by using ADC port.
Be aware that the minimum voltage of AREF is 1.0V.
Answer: Well, I think you should read the manual first before you use (and even perhaps brake it).
Generally speaking, analog reference is a voltage value between 0.00 and 5.00V, which will be used as virtual reference for all the analog inputs, you connect to your arduino board.
About analog reference is on Arduino site:
https://www.arduino.cc/reference/en/language/functions/analog-io/analogreference/

what is arduino adc reference?


How to delete partially downloaded updates in High Sierra?

Question: I'm trying to update my Macbook Pro to the latest security update for High Sierra but the download doesn't seem to finish and is working in a really weird way. I tried to cancel the current update, and it does cancel, but when I try to start it again, it doesn't start from the very beginning and shows an entirely different progress than what it showed before I cancelled it. For instance, I cancelled the download at around 700mb, but when I tried up update again, it shows that only 300mb has been downloaded.
I want to start the download from the start, from 0%, which I think will fix the issue but I can't seem to do that, too. Can anybody please help me? I tried to wait it out already, but it just gave me a connection error around 1.6GB. When I tried to start again, it started at around 738mb.
Comment: I would try a different approach and download from here: https://support.apple.com/en_US/downloads As far as I know High Sierra downloads tmp system updates to a file similar to this: `/private/var/folders/zz/zyxvpxvq6csfxvn_n00000s0000068/C/com.apple.SoftwareUpdate/CFNetworkDownload_XxxXxX.tmp` then assembles it into a subdirectory, before moving it to `/Library/Updates/`.  You can always boot into "Recovery", which should let you browse all directories.  Also a safe boot with an installation attempt there often helps.
Answer: Sorry, but I only have a partial answer to your question:
First off I would try a different approach and download from here: https://support.apple.com/downloads
Also a safe boot (pressing and holding the shift button at boot until the Apple symbol appears) with an installation attempt there often succeeds.
As far as I know High Sierra downloads tmp system updates to a file, or files similar to this: /private/var/folders/zz/zyxvpxvq6csfxvn_n00000s0000068/C/com.apple.SoftwareUpdate/CFNetworkDownload_XxxXxX.tmp
...then assembles them into a subdirectory, within...
/private/var/folders/zz/zyxvpxvq6csfxvn_n00000s0000068/C/com.apple.SoftwareUpdate/swcdn.apple.com/content/downloads/...before moving them to... /Library/Updates/.
You can always boot into "Recovery", which should let you browse all directories in Terminal (to be found under the "Utilities" menu).
Comment: This was very useful, thanks. In order to delete the data from /Library/Updates/ I had to additionally disable SIP first to avoid "Operation not permitted" error, as per https://appletoolbox.com/seeing-error-operation-not-permitted-in-macos-mojave/
Comment: I suppose I'll go with this instead. Also, I think it worked! Deleting the files, I mean. I deleted the files in the said directories but they App Store continues as if I've deleted nothing. However, when I booted into safe mode, everything went perfectly fine.
Comment: I've just observed the updates being downloaded to the system cache and moved the way I've described.  I've never tried to actually delete them; with all the other options to fix the issue, I never saw the need.
Comment: After a normal boot, just open the Terminal, type `sudo su -` and enter your password. Then it's good to go and delete those files.
Answer: This seems to be due to an interrupted or corrupted download. This can usually be resolved by clearing your Mac App Store cache.

Quit the Mac App Store
Go to Terminal and type following: open $TMPDIR../C/com.apple.appstore/
Move the files inside the folder to the Desktop or any temporary location (if you are confident, you can move them to Trash straight away.)

This should resolve the problem as temp files are cleared. For more information, read http://osxdaily.com/2016/10/08/mac-app-store-temp-cache-folder/.
If it is still not working, locate the folder /private/var/folders and open each subfolder inside it until you find com.apple.appstore. This stores the partial downloads. Do not delete any other files, only folders named com.apple.appstore.
Comment: This won't work. I also tried browsing folders in the /private/var/folders but I can't access some folders, so in the end I can't really delete anything. It says that I don't have the permission despite the fact that I'm using the admin account.
Answer: Option Click on the install button.


How can I create a custom callout view for MapKit user location?

Question: I have created a custom MKPinAnnotationView for all my map pins, but I'm having a problem customising the user location pin. If I create a custom pin for it, then I lose the blue pulsating dot and it is replaced with a pin, which I don't want. So I return nil in the viewForAnnotation method:
<code>- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
    if(annotation == self.mapView.userLocation)
    {
        // show the blue dot for user's GPS location
        return nil;
    }

    ... code for custom annotation pins goes here
}
</code>
However, I do want it to invoke a custom callout view when I tap on it. I've tried adding a subview when the blue dot has been selected:
<code>- (void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view
{
    if(view == [self.mapView viewForAnnotation:self.mapView.userLocation])
    {
        MKAnnotationView *userLocationView = [self.mapView viewForAnnotation:self.mapView.userLocation];

        userLocationCalloutView = [[MyAnnotationCalloutView alloc] initWithFrame:CGRectMake(-113, -58, 247, 59)];
        [userLocationCalloutView.rightAccessoryButton addTarget:self action:@selector(pinButtonTapped) forControlEvents:UIControlEventTouchDown];
        [userLocationView addSubview:userLocationCalloutView];
    }
}
</code>
But the problem with this is that the callout accessory button is outside of the hit area, and I cannot add a hitTest:withEvent because the blue dot annotation view is private... Any ideas?
Answer: You can get the built MKAnnotationView for the userLocation annotation in the delegate method mapView:didAddAnnotationViews:
<code>- (void)mapView:(MKMapView *)mapView didAddAnnotationViews:(NSArray *)views
{
    for(MKAnnotationView *view in views)
    {
        if (view.annotation == mapView.userLocation)
        {
            view.canShowCallout = YES;
            view.rightCalloutAccessoryView = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
            break;
        }
    }
}
</code>


Lego on Shabbos

Question: Is Lego Muktzeh? and can Adults use it too?
Comment: Why would you think it's muktzeh?
Answer: http://www.hakhel.info/archivesCABs/HAKHELCOMMUNITYAWARENESSBULLETINSummerPart25764.pdf
"Any toy that needs to be screwed together is prohibited because of the issur of Boneh.
Therefore, one may not play with a construction set on Shabbos. On the other hand,
because one merely sticks together the pieces, one is permitted to play with Legos,
Tinkertoys and the like on Shabbos."
Teshuvos written by HaRav Yisroel Belsky, Shlita
Comment: There is definitely a machloket on this - I have seen some hilchot shabbat books forbid it, some permit it, and some permit it only if it is intended to be taken apart relatively quickly. See your LOR.
Comment: Thanx alot  Curiouser
Answer: You seem to be asking two questions here:

Is Lego© Mutar for an adult to use? How about a child?
If it's only Mutar for a child, does that render it muktze for an adult?

(Perhaps I'm reading into your question because of the availability of my answer, but either way it will address your question.)
Hacham Ovadia Yosef, in Yechave Da'at (2:55), Addresses Lego©. (He starts off by saying that if something is Assur for adults, then its Assur for children too, yet) he seems to conclude that it's fine for children to play with Lego© on shabbat, but adults should stay away. He argues mostly that there's no melacha according to the Shulchan Aruch, but seems to be machmir for adults anyway (possibly because he is choshesh for the opinions that are machmir.) He restates this conclusion in Yabia Omer (O"C 7:39), where he says, "העלתי שמותר לתת לקטן 'אבני פלא' וכיו"ב לשחק בהם להרכיבם ולפרקם"
Regarding muktze, Hacham Ovadia in Yabia Omer (ibid.) says that Lego© is not muktze for an adult:

וגם נראה שמותר לגדול לתת לקטן לשחק בצעצועים המיוחדים לקטנים, ואין בהם
  משום מוקצה

Harav E. Y. Waldenberg, in Tzitz Eliezer (13:30), (also quoted in Yabia Omer, among other modern poskim that Hacham Ovadia quotes,) rules that Lego© is completely mutar, even for an adult:

(From 13:30.6)
בהא נחיתנא ובהא סליקנא דאין כל איסור בונה או סותר בבנית או סתירת אבני
  - פלא שהילדים שוחקים בהם.   וגם לרבות לא משום תיקון מנא.   ומותר לשחק בהם בשבת.   בכבוד רב וביקר אליעזר יהודה וולדינברג.

He backs up this pesaq din in 13:31, the following siman.
Answer: If the blocks are easily removed - even adults can play it.
But if you need to apply some force in order to connect/remove the blocks it more miskaem, so there
are different opinions on that case. When I asked about it my Rav he told that even in latter case there is no problem for adults to play it. However I've heard others that forbid playing hard-stucking lego to adults.
In any case, even if just children are allowed to play it - it is not a muktze.
Comment: in view of a number of similar active questions, it may be worth reminding everyone of the message in red print at the top of this page. For questions like this, one should always consult their own Rav.
Comment: I've asked my Rav, he lives in Bnei-Brak and his name is Refael Antin (there is no chance you can know him).
Source to the opposite opinion: שמירת שבת כהלכתה  פרק ט"ז , הלכה י"ח
He says that it is allowed to plays blocks that are easily removed, but it they are not easily removed it is forbidden, and in any case He says in halakha aleph that all toys are allowed just for children and not for adults. But there is a slight discussion in heara נ"ג, so the conclusion is a bit dimmed.
Comment: I need sources or even who you asked that told you this
Comment: Fair enough Jeremy; but I think it's a good question, everyone has "heard" the Lego is a problem for grownups, but it would be nice to know which poskim actually said it.
Comment: I have heard jutky's answer, but hard for whom to remove?  The user?
Comment: anyone find anything to agree with Jutky claim that some say it is OK
Comment: See my answer for sources of heter and the sources quoted therein (is that a word?) for sources of those who argue.
Comment: @jutky Maybe put that source (שמירת שבת כהלכתה) in the body of the answer itself? ....I know it's a little late, but I just got here....
Answer: Great answer by Baal Shemot Tovot
though extra sources brought here:

R' Pesach Eliyahu Falk (Machazeh Eliyahu 69) writes that while joining two pieces together is permissible, one shouldn't even allow one's children to play with Lego on Shabbos because building models could come under the prohibition of kesiva, and building a house with a roof could be creating an ohel.
Yet, many poskim including the Tzitz Eliezer (13:30-31) permit it. Seemingly, other poskim are primarily concerned for the prohibition of boneh. Both the Shemiras Shabbos Kehilchasa (16:18) and R' Belsky write that while construction sets that need screwing together are included in the prohibition of boneh, one is allowed to play with lego on Shabbos.
While R' Ovadia Yosef allows it (Yechave Daas 2:55 and Yabia Omer OC 7:39), he suggests that because of the above concerns, adults should ideally refrain from Lego building, though children may do so.
In conclusion, it is best not to build complete models or buildings on Shabbos, though it is okay to assist children with their Lego building
Comment: Classic Rabbi Falk
Answer: Dinonline writes,

It is permitted to play with lego on Shabbos, in particular where the
  purpose is not to leave the construction for a long time. For lego
  that will be left for a long time (sometimes true for small lego), one
  should be stringent.
Sources:
Where pieces are not fixed in place strongly, and it is normal to put
  them together and take them apart, it is permitted to play with lego
  (Minchas Shlomo 1:11).
See also Rabbi Pesach Eliyahu Falk (Shut Machazeh Eliyahu), who is
  likewise lenient for matters of boneh, but is stringent with regard to
  small lego because of the issue of "writing" (sculpting).
Answer: I have heard an opinion that it is permitted even for adults simply because the intended purpose of the Lego product is to put together and then take apart. Therefore, it's status would not change based on personal intentions or whether they are easy or hard for the user to take apart.
Comment: Why the downvote?
Comment: It's most likely because you bring no source for your claims. You simply said "I heard." Heard from who? Your rabbi? Your neighbor?

Lego on Shabbos


Was the historical Buddha infallible?

Question: Could he have erred, even as the enlightened one?
Answer: Yes, a Sammasambuddha does not make mistakes as they are omniscient and do not have any Vāsanā remainders.
Answer: It depends on what you mean by failing. Also, for clarity sake, one thing is to ask whether he did made mistakes and the other to ask if people believe he was capable of making mistakes.
If by mistake it's meant a "moral mistake",  he is seen as very consistent in the texts and buddhists regard him as incapable of error here. After all, morality is not only his expertise: he is regarded as embodying perfect morality as direct consequence of his accomplishment of eradicating mental defilements (the very root cause of moral mistakes).
If by "mistake" it's meant a "false statement", he is also regarded as incapable of that: the texts explicit say arahats can't lie, and buddhists believe it so. Now, much of the teachings show him going long distances to be careful with what he say, which is particularly suggestive that he was indeed capable of that.
If by "mistake" is meant any action that does not seem to accomplish a certain goal (unrelated to failing morality), this is harder to evaluate and there are some interesting episodes that can be interpreted either way. Also, many buddhists regard him unable to err.
One interesting example that @ChrisW's answer mentioned is the nun order: first, the Buddha said "Do not ask so" to the women looking to be accepted in the sangha, and later on, he finally conceded when Ananda asked in their behalf. In this case:

Those who believe he can err might see this episode as evidence that he either had doubts or had to make decisions without knowing if they would lead to an implicit goal (e.g: of helping more people, growing the sangha, etc).
those who believe he can't err might see this episode as he making the correct decision early when he refused to accept nuns and later making the correct decision of accepting them (e.g. circumstances might have changed)

Unfortunately, both positions make assumptions that are hard to probe. They assume the reasons for the rejection and acceptance which are a mystery to us.
Comment: The inition rejection was intentional. It served as a precursor to introducing special rules for nuns and getting them to embrace those without question. It  was also meant to give a clear signal to the community of Sangha about the seriousness of mixing 2 genders in a celibate environment.
Comment: @SankhaKulathantille ... which would not be grounds for dispute were this explanation have been given by the Buddha himself when the women asked him the first time. One can try to infer benefits caused by the delay, but I find valuable his advice to "leave what I left unsaid as unsaid".
Comment: it could have been grounds for dispute had he just accepted the request so easily and then introduced the rules. I would say it's a clever ploy employed by the Buddha to make the group of women understand the seriousness of the request.
Answer: Some people argue that e.g. his allowing Devadatta to become a monk was a mistake ("erring"); others argue that that was no mistake, and had a good outcome (or, at least, best possible outcome).

The fact that the Buddha describes his own, actual experience (of the way to enlightenment), not mere conjecture or hearsay, is a reason for his statements being real or true.
The fact that he was careful when he spoke, e.g. when he doesn't answer the unanswered questions, helps to make him "infallible" (or never-wrong): those are examples of times when he might have failed but didn't, for example the Abhaya Sutta starts with a question which was intended to make the Buddha fail.
I suppose another doctrine which makes it difficult to point to example of where the Buddha "erred" is the doctrine that "each person is responsible for their own kamma": so if someone else (e.g. one of hs students) errs, then that doesn't count as for example a failure in leadership or a failure to teach.
Also I'm not sure what you're asking but given the word "infallible" and your (Mexican) background, perhaps you mean infallible about doctrine, like the Catholic Pope is reputed to be. That's a narrower/more specific question, for example here:

As a biblical example of papal fallibility, Fundamentalists like to point to Peter's conduct at Antioch, where he refused to eat with Gentile Christians in order not to offend certain Jews from Palestine (Gal. 2:11–16). For this Paul rebuked him. Did this demonstrate papal infallibility was non-existent? Not at all. Peter's actions had to do with matters of discipline, not with issues of faith or morals.

If you restrict the question to matters of doctrine-and-not-discipline it's even easier to answer "yes infallible; no error". For example the Buddha is said to have reversed his own previous pronouncement on the question of whether women might become monks (nuns), and I suppose someone might argue that must be therefore an example of the Buddha "erring", either in his original decision (that women cannot or may not join the Sangha), or in his reversal (that they can). Similarly, apparently various rules of the vinaya were added over time as necessary. If you exclude all those and say "Well that's about discipline, not about doctrine" then counter-examples to infallibility are harder (if not impossible) to identify.

Also, and I'm not completely sure about this but I'm pretty sure, that the Buddha's words are (i.e. the Buddha's doctrine is) usually understood to be or defined as true.

If it's the Buddha's doctrine then it's true
If it's not true then it's not the Buddha's (true) doctrine

You might see an example of that in this answer and this comment where some detail that's published as "doctrine" is assumed to be a later error, introduced into the doctrine by someone else (i.e. by someone other than the Buddha).
There also seems to me to be a certain amount of self-contradiction within the doctrine. I think this is assumed to be (explained as being) because the doctrine is simplified or condensed, maybe for various stages of understanding. If I can try to invent an example of that:

Suffering exists, caused by desire, suffering ceases when desire ceases
Actually it's not as simple as "cessation of desire": there are actually two kinds of desire, i.e. wholesome and unwholesome, and it's only the unwholesome desire that you're supposed to abandon
Actually it's not as simple as "cultivation of wholesome desire" because once you have attained the Wholesome you need no longer desire it for yourself
Actually it's not as simple as "not desiring it for yourself", etc.

Or here is another example, quotes from A Still Forest Pool (the author was a respected contemporary Buddhist teacher):

Go Left, Go Right
A Western monk at WatBa Pong became frustrated by the difficulties of practice and the detailed and seemingly arbitrary rules of conduct the monks had to follow. He began to criticize other monks for sloppy practice and to doubt the wisdom of Achaan Chah's teaching. At one point, he went to Achaan Chah and complained, noting that even Achaan Chah himself was inconsistent and seemed often to contradict him self in an unenlightened way.
Achaan Chah just laughed and pointed out how much the monk was suffering by trying to judge others around him. Then he explained that his way of teaching is very simple: "It is as though I see people walking down a road I know well. To them the way may be unclear. I look up and see someone about to fall into a ditch on the right-hand side of the road, so I call out to him, 'Go left, go left' Similarly, if I see another person about to fall into a ditch on the left, I call out, 'Go right, go right!' That is the extent of my teaching. Whatever extreme you get caught in, whatever you get attached to, I say, 'Let go of that too.' Let go on the left, let go on the right. Come back to the center, and you will arrive at the true Dharma."

And:

The Middle Way
The Buddha teaches us to keep laying down the extremes. This is the path of right practice, the path leading out of birth and becoming. On this path, there is neither pleasure nor pain, neither good nor evil. Alas, the mass of humans filled with desiring just strive for pleasure and always bypass the middle, missing the Path of the Excellent One, the path of the seeker of truth. Attached to birth and becoming, happiness and suffering, good and evil, the one who does not travel this Middle Path cannot become a wise one, cannot find liberation. Our Path is straight, the path of tranquility and pure awareness, calmed of both elation and sorrow. If your heart is like this, you can stop asking other people for guidance.

You might see that these may appear to contradict each other ("go left, go right, our path is straight"), but I think that it's the student that's assumed to be incorrect or vacillating, and the Buddha (and Buddha-Dhamma) that's assumed to be infallible/accurate.

The question of infallibility is I think related to doubt, i.e. you ask that question when you have doubt about the doctrine. "Doubt" is described in the doctrines, see e.g. Vicikitsa on Wikipedia.
There's further detail in the Vicikicchā article on Dharmafarer, which identifies many types of doubt, and their effect. Towards the end it says that an opposite of doubt is faith:

The opposite of doubt is faith (saddhā), which arises when our doubts
  about the Dharma or the Vinaya are cleared up. But faith can be already present in us in some measure.
  We could be faith-inclined people who easily believe others. This is good when we follow good and wise
  teachers, but bad when we are misled by dubious gurus.
Early Buddhism distinguishes between blind faith or "rootless faith" (amūlika,saddhā), that is, baseless
  or irrational faith, and wise faith (avecca-p,pasada), that is, "faith with a good cause" (akaravati,-
  saddha), faith founded on seeing. The Vinaya defines the word amulaka as "not seen, not heard, not
  suspected." This definition is a legal one, ascertaining whether something has been seen, or spoken by
  someone, or suspected to have happened so that proper action follows. But both in a Vinaya and Dharma
  situation, further investigation is often necessary or desirable for the truth to be revealed. True reality, as a
  liberating experience, however, can only be discovered by us for ourselves: it is a personal and direct experience.

The word "faith" in Buddhism doesn't necessarily mean exactly the same as "faith" in Christianity (see also this topic).
Also the Theravada tradition teaches that there are Four stages of enlightenment; and "doubt about the teaching" is one of the fetters; and not having doubt about the teaching is associated with the first stage of enlightenment. Especially if you're a 'doubting Thomas' I think that would include seeing/understanding/experiencing the doctrine for yourself.
Comment: The four noble truths do not refer to 'desire' (chanda) therefore there appears to be no self-contradiction within that doctrine. Instead, the four noble truths refer to craving (tanha).
Answer: In respect to the core teachings ('heartwood'), a Buddha is infallible. These core teachings are those of ultimate truth (lokuttara dhamma), namely, the Four Noble ('Ariya' - Irrefutable) Truths, the Three Characteristics, Dependent Origination, the Elements (Dhatu) & Emptiness (Sunnata).
The Four Noble Truths, for example, are infallible because what they explain cannot be disproven by any person, namely: (i) all suffering is egoistic attachment; (ii) this suffering arises when there is craving leading to new ego becoming; (iii) this suffering will end when this craving ends; & (iv) the noble eightfold path ends suffering.
Or the Three Characteristics cannot be disproven, namely all conditioned things are: (i) are impermanent; (ii) cannot bring lasting happiness; & (iii) cannot be ultimately owned or possessed.
MN 117 separates wisdom, & thus the teachings, into two kinds: (i) pure teachings of ultimate truth ("without effluents") leading to liberation ("transcendence" from the world); & (ii) moral teachings ("siding with merit") with "effluents" connected to "kamma" & the "worlds".
In a number of places (MN 136; AN 4.77; etc), it is explained the principles of moral kamma (action) & result ('vipaka') are not exacting but merely general principles (for example, good kamma while generally leading to good results can also lead to bad results).
This makes these explanations (MN 136; AN 4.77; etc) about the non-exact nature of kamma infallible since they cannot be disproven. In other words, the general teachings about kamma (good leading to good; bad leading to bad), due to not being 100% true, cannot be used to deem the Buddha as fallible.
Therefore, anything that is 'worldly' in nature, such as moral teachings about kamma, the success & failure of students, the structure & rules of the Sangha (community, including admission of women), etc, cannot be used to deem the Buddha was fallible.
The Pali scriptures are clear the Buddha kept silent when asked would he lead all beings to liberation (AN 10.95). The scriptures (AN 4.111) are clear about the success of students ultimately depends on the disposition of the student rather than on the instruction of a Buddha.
Again, AN 10.95 & AN 4.111 are infallible, i.e., cannot be proven to be untrue, since Buddhism has existed for 2,600 years and all beings on the earth are not liberated from suffering, let alone 1% of them.
In addition, DN 16 offers the principle of the Four Great References, which allows for scrutiny of contradictions in teachings given by other monks or created in later years. There are contradictions in the Pali suttas (eg. MN 64, which states a new born child has no idea of 'self'; and MN 123, which claims the Buddha had ideas of 'self' the moment he was born from his mother's womb; SN 22.79, which states ideas of 'self' existing in the past are delusions; and AN 3.15, which claims the Buddha declaring he existed in a past life). If the principle of the Four Great References is followed, it is easy to weed out the unverifiable teachings that comprise of a immeasurable fraction of the scriptures  (eg. MN 123; AN 3.15) with the core principles found in the vast majority of the teachings (which support MN 64; SN 22.79, etc).
Some teachings (particularly about 'rebirth') may appear unverifiable however this impression only occurs when the language of these teachings is not fully understood. The Commentaries state:

The Awakened One, best of speakers,  Spoke two kinds of truths:  The conventional and the ultimate.  A third truth does not obtain.
Therein:  The speech wherewith the world converses is true  On account of its being agreed upon by the world.  The speech which
  describes what is ultimate is also true,  Through characterizing
  dhammas as they really are.
Therefore, being skilled in common usage,  False speech does not arise in the Teacher,  Who is Lord of the World,  When he speaks
  according to conventions.
(Mn. i. 95)
Comment: Could you explain, using references and/or personal experience (and/or reasoning), why you say (what your reason is for saying) that "the Lord Buddha was infallible"? If you don't include that kind of information in your answer, then you're just asking th OP to trust you as if you were their teacher (see e.g. the meta-answers [here](http://meta.buddhism.stackexchange.com/a/1565/254) and [here](http://meta.stackexchange.com/a/110170/139866)).
Comment: @Dhammadhatu I'd greatly appreciate an argument that does not rely in scriptures.
Comment: This is not possible because the scriptures accord with the moral principles or integrity of an honest person, namely, the teachings are to be verified by each person for themselves. All of the teachings of ultimate truth can be verified by meditation. This is the only way to prove infallibility.
Answer: The Pali Canon clearly considers the Buddha to have been omniscient and he was apparently considered to be a reliable oracle by King Ajatashatru, who tried to use him to predict whether his war against the Vajjians would be successful or not (DN 16). Of course, one can rationalize these references and interpret them in many different ways, but the assertion that he was omniscient occurs in the earliest Buddhist texts.

Was the historical Buddha infallible?


How is object different from a file?

Question: How do Walrus, S3 or any cloud storage system, take in a file and convert it to object programmatically?
Comment: The difference is only in definition.  A file is an entity inside a file system.  Since e.g. S3 is not exactly a file system, they call their entities something else.  You can think of them as the same.
Answer: If you're asking how does S3 lay its objects out on disk on its internal servers, we don't know (the implementation details are not public.)
What they are very likely doing is taking your object's key (bucket + path) and consulting a  consistent hash that maps your object to a set of servers.  The upload is directed to one of these servers (essentially at random) which stores it and enqueues future work to propagate the new object to the other servers responsible for replicating it.
This replication delay is the underlying need for eventual consistency.  I also heard once somewhere that Amazon uses an error-correcting encoding at the storage level to further defray bad reads.
Answer: To get the general understanding of how Cloud Object Storage systems stores the objects(Binary Files), you can read the documentation of Swift Object Storage-Openstack.
Swift is similar to Amazon S3 and hence to Walrus.
Swift communicates through the Proxy Server to Clients(Outside of the Cluster) and Client can store,delete the objects through the RESTful HTTP API. The server maintains the Ring-Configuration file that maintains the mapping between files and their physical location.
When there is a request to upload a file, MD5 hash is calculated from the path of the file.
Please find the details at:
Openstack Swift Architecture
Swift Documentation

How is object different from a file?


Where can I farm Berserker and Reflex Guard mods?

Question: Can these mods only be obtained by using Nekros skill, or can they be obtained without using that skill with low drop rate?
Comment: I know Reflex Guard mods drop commonly from low level survival. If you go to an enemy that drops it, you can desecrate the dead body of it for a second chance to get the mod.
Answer: The Reflex Guard mod is obtained as a rare drop from Corrupted MOAs. They can also be found as rewards from Tier 1 Void Survival. The Berserker mod is obtained as a rare drop from Corrupted Ancient Healers, or can gotten through transmutation.
You can use Nekro's Desecrate skill on these two types of enemies once they die, in order to have a second chance at receiving one of these mods. Personally, I suggest you do void survival, defense, or exterminate missions for the best shot at getting these mods.
Answer: You can get them from Transmutation or as a drop from corrupted ancients.


Homodyne and heterodyne detection

Question: Very basic question here. I searched it on the net but cudn't get very convincing answers.
Can anyone explain me Homodyne and Heterodyne detections in rf domain. Mathematically is much appreciated.
Answer: I'll assume AM DSB modulation for simplicity, but the same idea applies to quadrature modulation. I'll assume that the received signal has been properly bandpass filtered. I'll also ignore noise and carrier synchronization.
So, the received signal is $$r(t) = s(t)\cos(2\pi f_c t).$$ We want to recover the baseband signal $s(t)$ from $r(t)$. The bandwidth of $s(t)$ is $B$ and the bandwidth of $r(t)$ is $W=2B$. The signal $r(t)$ is centered on $f_c$; we would like the receiver to accept $f_c$ as a parameter set by the user (we say that the receiver should be tunable).
A homodyne receiver calculates $$\hat{s}(t) = \text{LPF}\lbrace r(t) \cos(2\pi f_c t) \rbrace.$$ While mathematically this is super simple, in practice this receiver is extremely difficult to implement. This was especially true in the early age of radio, where the entire system was analog and the theory was not yet well understood.
The heterodyne receiver (invented by the unsung, tragic genius Armstrong, as pointed out by Stanley) recovers $s(t)$ in two (or more) stages. First it calculates
$$s_{IF}(t) = \text{BPF}\lbrace r(t) \cos(2\pi f_1 t) \rbrace,$$ where $f_1$ is selected so that $s_{IF}(t)$ is centered at frequency $f_{IF}$.  In a second stage, the receivers calculates $$\hat{s}(t) = \text{LPF}\lbrace s_{IF}(t) \cos(2\pi f_{LF} t) \rbrace.$$ The point of this receiver is that the second stage is independent of the chosen value of $f_c$. This single idea simplifies the implementation so much that it is actually the reason we've had radio at all for the past 70-80 years.
If you're interested in this subject, there are two books I can't recommend enough:

"The science of radio", by Paul Nahin.
"Man of high fidelity", a biography of Armstrong by Lawrence Lessig.

On the technical side, I like the presentation of different modern receiver architectures in

"RF system design of transceivers for wireless communications", by Qizheng Gu.
Answer: Heterodyning was invented by Armstrong. Its really a cheaper way to implement analog bandpass RF filters using a set of cascaded fixed band filters to tune to a segment of the RF spectrum that contains a broadcast station.
Analog filters have temperature and age related drift issues and need to be "tuned" periodically. When consumer radio receivers were first mass produced it was recognized that translation to an intermediate frequency (IF) where there was a cascade (stages) of fixed RF band pass filters followed by a single detector (demodulator) would offer advantages over having a set of separate bandpass filters for each station or a cascade of variable frequency filters or a separate detector for each broadcast station.

Homodyne and heterodyne detection


Zero to Bitcoin in sixty seconds - how to set up a Bitcoin client in case you need it fast?

Question: Lets say I have a bitcoind instance running on a server with proper wallet.dat backups created regularly. The server crashes, blockchain data becomes corrupted or what have you, and I need to set up a server client fast to take over traffic. Moreover, I need the service to be interchangeable with the official client - that is it needs to provide the same RPC commands, conform to the wallet.dat specification so it can be interchanged between the clients and so forth. What is the fastest way one can do that in case of emergencies?
Answer: Well, I would run the bitcoind in a VM, and regularly snapshot it.  If it fails, rollback the snapshot and reboot. Back online in < 10 min, assuming frequent backups and you start working right away.  Not sure if this is the use case you're asking about, but that's what I'd do for max uptime.
Answer: lordcirth's VM suggestion is great, but let's build upon it. Let's think of it more like an elastic cloud VM instead of a snapshotting procedure.

VM with bitcoind, optional snapshotting, but definite periodic backups of wallet.dat. Period is equal to the expected rate of change of the wallet.
Blockchain files are stored locally but also periodically backed up to a remote disk. An increment every 2 hours would probably suffice, with the standard Grandfather-father-son rotation. At 10 minutes per block, that's 8640 blocks that you could be behind with backups a day behind. Son is the semi-daily, father is every 12 hours, and grandfather weekly, with perhaps a great grandfather monthly.
When something bad happens to the running VM, don't waste the time rolling back the snapshot. Just fire up a new VM and have it get the latest backup from the remote disk.

In my mind, snapshots are for when you make a change that you want to roll back.
When you want a highly available service that when automated can maximize uptime, go the disposable VM route. The bonus is that you get can spin up additional bitcoind servers on local metal or within each instance and have an authoritative backup ready to go for them. You'll just have to manage the wallet.dat coordination, since multiple bitcoind processes can't share those, either.


How to spend from a paper wallet private key using a desktop app without a mobile app?

Question: I have a paper wallet and the private key. What methods can I do on the desktop to send a portion of these bitcoins using only a desktop app? Is there an app where I can type in my private key and select how much to send?
Answer: When you launch Electrum for the first time, it wants you to create a new wallet. Same when you just choose File → New/Restore at any point.
Then, choose "Restore a wallet or import keys" and "Standard wallet". On the next page, enter your private key. The password you can choose afterwards is optional and you can skip it or only remember for the period of time you're keeping this wallet on your computer.
If you want to try this in advance without typing your own private key in, you can use the private key KzbvEHb1HvDRZMPvVF7Du9F4N5g22QkeoeZ7qPCkjSPktt5bbCDU. Is has had 50 mBTC going in and out again as you can see on the blockchain.info page about its corresponding address 15dNGcjVE8ddCt3vgYwcpJjYXK4ydZtykF and you can find out how Electrum shows this to you if you create a wallet using it. This private key has been specifically created by me to be publicly known.
Note that Electrum won't be able to create more addresses from it because it only is a single private key. It is, however, able to show the one address the private key corresponds to.
You can use my answer to your question "
How do you send to multiple addresses by paying a one time fee? Which wallet supports this?" to transfer the remaining money back to the address it came from so you can spend it using the same private key in the future.
Answer: Most desktop wallets will let you do an import of a private key. For security reasons, they usually will make you spend the amount to another address.
Armory has a private key import feature and you can spend some back to the same address (not recommended).


Under which circumstances can »werden« stand at the end of a sentence?

Question: My listening understanding is poor, but I frequently and clearly hear the word werden used at the end of sentences.
What grammatical structure allows this and what is its function in this position?
Comment: @peterh *das* Land
Comment: @LeonardoLuiz Another possibility is a modalverb + Passiv construction. For example, "The problem can be solved" means: "Das Problem kann gelöst werden". Here is "werden" always in infinitiv.
Comment: Give us examples. There are *a lot* of constructions, where werden goes to the end. The most likely is that you've found a Passiv in a Nebensatz. For example: "The county, which is under destruction" means: "Der Land, der vernichtet wird"
Comment: I'm trying to figure out what natives are saying, since my listening is not good yet, many times I only grasp "werden" at the end of a sentence. Exactly werden (infinitiv).
Comment: Maybe first you should learn grammatik...
Comment: @Philipp Danke :)
Comment: Thanks, @peterh, now I can reverse engineer die grammatik ;)
Comment: @LeonardoLuiz You are a programmer, it is good! German is a very nice language for programmers!
Answer: As peterh pointed out in his comment, werden is frequently used in passive constructions:

Das Problem kann gelöst werden. (peterh)
  [X] + [kann / könnte / sollte...] + [Verb im Perfekt] + [werden].

Another option are subordinate clauses (Nebensätze), where the word order is changed compared to main clauses:

Ich frage mich, ob die Briefe heute noch ankommen werden.

In this case, werden is not actually an infinitive, but is the inflected form (third person plural; but the same applies for the the first person plural) of the same verb werden.
Its function here is to set the sentence in future tense.
Werden has many uses in the German language, as you can see in this overview with explanations at canoo.net.
Answer: werden has basically 3 meanings in German:

"to become something". It is not in infinitive, but in first and third person plural (and in the polite-form "sie") it looks so: "Die Schüler werden Programmierer" means: "The studends become (...are becoming) programmers".
Hilfsverb for Passive. Here the important thing is to know: what is coming with "is + perfekt" on English, is going with "werden + perfekt" in German. Thus, "It is done" means "Es wird erledigt". Here the "werden" is not in infinitive-form, but as in the previous point, sometimes it looks the same.
Hilfsverb for future. It is the same as the English "will" hilfsverb, except that here the original Verb goes to the end of the sentence. For example: "I will learn more German" means: "Ich werde mehr Deutsch lernen".

You will most likely find (1) and (2).
Now, here werden is mostly not in infinitive-form and not at the end of the sentence. The most likely reasons, why it could become infinitive form:

"we will", "they will", "You will" are all "werden". It looks like an infinitive, but it is not.
If it is part of a vorgangspassive structure, and it has got a hilfsverb. Like: "Das Hotel kann aufgebaut werden."

The most likely reasons, why it can go to the end of the sentence:

It is part of a subordinate clause (Nebensatz). In German, there Verbs are going to the end of the sentence.
Like (5).

You can freely combine these possibilities, to find your best variant.
These all are looking chaotic, because you clearly don't know the grammatik of the German verbs. But, in fact these are simple and very logic. Because the whole German Language is very logic.
If you have a programmers vein: you essentially asked: "How can this function result 5?". To describe, how can a function result 5, might be complex. But not if you understand, how the function works.
Comment: I wouldn't say that the future tense is dying out, it's just used less often than in English. "Ich gehe nach der Arbeit einkaufen" is more natural than "Ich werde ... gehen", yes. But "Nächstes Jahr werde ich mehr Deutsch lernen" sounds much more correct than "Nächstes Jahr lerne ich mehr Deutsch".
Comment: @KWeiss Thanks. I hope you will have right. :-) Btw, also I use Futur1 as I've learned and ignore this new fashion. If something is in the future, it requires Futur1. :-) But, I think Futur2 would be maybe too strong from a foreigner :-)


Palladium hydride forming water and heat at room temperature

Question: I just read that saturated palladium hydride, $\ce{PdH}$0.7, when exposed to oxygen will generate heat and water on it's surface, $\ce{4 H}$(Pd) $\ce{+O2}$(g) $\ce{\to 2 H2O}$(g, l).
What is going on?
Answer: I'm not an expert, but typically there are a series of surface reactions where the reactive species are all adsorbed on the surface. So atomic hydrogen wouldn't "leave" the palladium before it reacts, it just diffuses from an internal crystal site to a surface site.
Likewise, the oxygen would adsorb onto the Pd surface, I'll assume dissociatively. So now there is atomic O and H diffusing around the surface sites of the Pd. These can react and form adsorbed OH, which can further react and form adsorbed H2O, which can then desorb and give you your water.
Your enthalpy calculation is off, the equation for water already includes the fact that an oxygen molecule must break apart to form it.
If you include the hydrogen gas reaction with Pd in your picture, all you're doing is turning hydrogen gas and oxygen gas into water, using Pd as a catalyst. So the total enthalpy change is just -285.83kJ/mol. You don't have enough information to determine how much heat is released (or absorbed possibly) in the hydrogen absorption reaction and how much is released in the water production reaction, but the total of the two will be -285.83kJ/mol.
Answer: I'm guessing that when the $\ce{H}$ atoms leave the palladium are they still monatomic for an instant, but without the $\Delta H^0_f = 436 kJ/mol$ extra energy that free  $\ce{H}$ atoms would normally have, as bypassed by the $\ce Pd$ somehow. Most of the $\ce{H}$ atoms simply fall in step with one another, reforming $\ce{H2}$ without a peep. But some latch onto nearby $\ce{O2}$ molecules, disassociating them and forming $\ce{H2O}$.
The heat generated is the difference between heat required to dissociate the $\ce{O2}$ and the heat generated by the formation of $\ce{H2O}$.
$\ce{O2 \to 2 O}$   $\Delta H^o_f = 247.5 kJ/mol$
$\ce{ H2 + 1/2 O2 \to  H2O}$ $\Delta H^o_f = -285.83 kJ/mol$
$∴ \ce{2H_{(Pd)} + 1/2O2_{(g)} -> H2O_{(g, l)}} \quad \Delta H^o_{\mathrm{f}} = -38.33 \mathrm{kJ/mol}$
Being as this is only$\ 5.68 kJ/mol$ short of the heat required to vaporise $\ce{H2O}$, it explains why some of the product would be gas and some liquid.
This is a complete guess, am I hilariously wrong here?


Angular momentum and angular velocity

Question: The angular velocity $\vec{\omega}$ lies along the axis of rotation. And the angular momentum $\vec{J}$ is the cross product of $\vec{r} \times \vec{p}$. Which according to me should also lie along the axis of rotation. But I read in a book that the direction of angular momentum vector and angular velocity vector are not the same. Why is it so?
Answer: The formula you have specified $\vec{L} = \vec{r} \times m\vec{v}$ is the definition of angular momentum of a point-like particle which respect to a point P. In this case of course angular momentum and angular velocity have the same direction.
When dealing with rigid bodies (assemblies of many point-like particles), the correct full angular momentum is proved to be:
$$ \vec{L} = I \vec{\omega} $$
where in general $I$ is a tensor (a matrix for simplicity) depending on shape and mass distribution of the rigid body, called inertia tensor.
It is possible, in general, that once you choose a reference frame (say with $\omega$ parallel to the $\hat{z}$ axis), the inertia tensor could be diagonal or not in that basis. If it's diagonal, then $\vec{L}$ is parallel to $\vec{\omega}$, otherwise it is not.
As an example, you can consider a cylinder forced to rotate about an axis which is not parallel to any of its principal axes of symmetry.
I hope I've answered your question properly; if not, please ask for details.
Answer: The answer provided by @Matteo is a correct explanation. However, I wanted to expand on the supplied equation
$$\mathbf L=\hat I\boldsymbol\omega$$
where $\mathbf L$ is the angular momentum of the rigid body, $\hat I$ is the moment of inertia tensor, and $\boldsymbol \omega$ is the angular velocity vector of the rigid body. If we write this equation out explicitly for three dimensions we have:
\begin{equation}
\begin{bmatrix}
L_x \\
L_y \\
L_z \\
\end{bmatrix}=
\begin{bmatrix}
I_{xx} & I_{xy} & I_{xz} \\
I_{yx} & I_{yy} & I_{yz} \\
I_{zx} & I_{zy} & I_{zz} \\
\end{bmatrix}\cdot
\begin{bmatrix}
\omega_x \\
\omega_y \\
\omega_z \\
\end{bmatrix}
\end{equation}
Each element of the moment of inertia tensor is given by
$$I_{jk}=\int\rho(\mathbf r)\left(r^2\delta_{jk}-jk\right)\text dV$$
where $\delta_{jk}$ is the Kronecker Delta and $\rho$ is the mass density function. For example:
$$I_{xx}=\int\rho(\mathbf r)(y^2+z^2)\text dV$$
$$I_{xy}=-\int\rho(\mathbf r)xy\ \text dV$$
and so on.
So now let us ask, along the lines of your question, what must be true so that $\mathbf L$ and $\boldsymbol\omega$ point in the same direction? Well, if two vectors point in the same direction, then it must be that one is a constant multiple of another. Therefore, for some constant $\lambda$ we must have
$$\mathbf L=\lambda\boldsymbol\omega$$
Using our first equation this must mean that:
$$\hat I\boldsymbol\omega=\lambda\boldsymbol\omega$$
This is an important type of equation seen a lot in linear algebra and its applications. Mathematically, this means that we want $\mathbf\omega$ to be an eigenvector of $\hat I$ with an eigenvalue of $\lambda$. Physically, this means that if we rotate our object about an axis such that $\hat I\mathbf\omega=\lambda\mathbf\omega$ (these types of axes are called "principle axes") then our angular momentum and angular velocity vectors will point in the same direction. If this is not the case, then our two vectors will point in different directions.

It is worth mentioning that in typical introductory physics classes we are usually only operating with coordinates aligned with the principle axes, which coincide with axes of symmetry for the volumes that are usually considered (this makes our moment of inertia tensor a diagonal matrix). For example, when you see that the moment of inertia of a disk is $\frac12MR^2$, what this really is telling you is $I_{zz}=\frac12MR^2$, and we only consider the disk that rotates about this axis such that $\boldsymbol\omega=\omega_z\hat z$. Therefore, our equation becomes
\begin{equation}
\begin{bmatrix}
L_x \\
L_y \\
L_z \\
\end{bmatrix}=
\begin{bmatrix}
I_{xx} & 0 & 0 \\
0 & I_{yy} & 0 \\
0 & 0 & I_{zz} \\
\end{bmatrix}\cdot
\begin{bmatrix}
0 \\
0 \\
\omega_z \\
\end{bmatrix}=
\begin{bmatrix}
0 \\
0 \\
I_{zz}\omega_z \\
\end{bmatrix}
\end{equation}
So, in other words, $\mathbf L=I_{zz}\omega_z\hat z=\frac12MR^2\omega_z\hat z$.
Answer: The physical quantity which connects angular momentum $\mathbf{J}$ and angular velocity vector $\boldsymbol{\omega}$ is the moment of inertia. However, this quantity is not a scalar.
A scalar would not depend on the coordinate system. In the following it is assumed that the rotation axis will be along the z-direction. Then look at the following example: Turn a cylinder of uniform mass density and length $l$ around its symmetry axis. In this case the moment of inertia is
$$I =\frac{1}{2}mr^2$$
where $m$ is the mass of the cylinder and $r$ its radius. Now turn the cylinder so that the rotation axis is $90^{\circ}$ perpendicular to the symmetry axis. The moment of inertia is not the same.
$$I =\frac{1}{4}mr^2 +\frac{1}{12}ml^2$$
Turning the cylinder again so that the rotation axis (z-axis) is the third axis of the cylinder (also perpendicular to the symmetry axis) is identical to the second case. So depending on the orientation of the cylinder in the chosen coordinate system the moment of inertia of the cylinder is different.
This behavior of the moment of inertia can be expressed by the following diagonal matrix (here it is assumed that the symmetry axis of the cylinder is along the z-direction.
$$I = \left(\begin{array}{ccc}  \frac{1}{4}mr^2 +\frac{1}{12}ml^2 & 0 & 0\\ 0 & \frac{1}{4}mr^2 +\frac{1}{12}ml^2 & 0 \\ 0 & 0 &\frac{1}{2}mr^2\end{array}\right)$$
Nevertheless in these cases for each chosen axis -- called principal axis --$\,\,\,\boldsymbol{\omega}$ is still parallel to $\mathbf{J}$.
The matrix form of $I$ already suggests it: The moment of inertia is actually a tensor and only if the coordinate system is chosen to coincide with the three principal axis of a given mass distribution (here a cylinder) it can be written in form of a diagonal matrix. If this is not the case, imagine a rotation axis (still identical with the z-axis) which is inclined $\neq 90^\circ$ to one of the principal axis of the body (here a cylinder), the matrix $I$ becomes non-diagonal and the relationship between $\boldsymbol{\omega}$ and $\mathbf{J}$ becomes more general:
$$  \mathbf{J}= I \cdot \boldsymbol{\omega}$$
where the $\cdot$ is a matrix product multiplication. In this case $\,\,\,\boldsymbol{\omega}$ is no longer parallel to $\mathbf{J}$.

Angular momentum and angular velocity


Resources for word nuances?

Question: I'm currently trying to translate a speech E-J, and I'm aware I could get things wrong if I don't understand the nuances of Japanese words - which, put simply, I don't. My level is very basic, and I'm writing a speech at a level higher than I can presently do with just my own resources. I can probably find my way around dictionaries, but one thing I don't know how to do without keeping a Japanese translator on hand, or posting a question to JSE or /r/LearnJapanese every ten minutes, is learning the nuances between words. Is there any resource suited for this purpose?
Answer: The best response I could give is to use the resources at Resources for learning Japanese: thesauruses tend to help with differentiating between similar words, dictionaries for getting the general definition, and corpora for hypothesizing whether it's correct to use words and phrases etc in a certain way.
I often use Space ALC for figuring out the general gist of how words are used, and Weblio for the thesaurus, English/Japanese dictionary and native Japanese 大辞林 dictionary (native dictionaries tending to be a more accurate indicator of nuance than bilingual) among other resources, but different people will have different preferences.
Even if you do draft it yourself, I strongly recommend having a native speaker check over your speech to fix mistakes and unnatural phrasing if possible.

Resources for word nuances?