How did smaller feudal vassal realms survive a war or raid?

Question: Say you're a knight or baron or just generally a landowner who swears fealty to a much more higher title than you. One day a war breaks out between a rival realm or raiders from a more tribal-like one attack and your lands get devastated, how did you recover? Especially if almost all your peasants/villeins and serfs were killed in the attack.
Comment: The simple answer is that the vow of fealty obliges the liege to aid the vassal, and the attacker is unlikely to kill all the peasants - that would render the land unworkable.  The goal is conquest - to take possession of the wealth.  Remember that their economics is based on land rent.  (Obviously the 100 years war is slightly different.)
Comment: Seems like a classic question about the difference between *limited war* and *total war*. Killing an entire village (or Barony) and devastating their lands is an enormous amount of (often unnecessary) extra work beyond ordinary battle and perhaps a bit of pillaging. The Knight (or Baron) is likely to perish early in the conquest, so how *they* would recover seems moot.
Comment: This is a fine question and better suited for the History stack; this was something real.
Comment: Moreover, many medieval wars settled inheritance issues about who is the legitimate ruler. It would be hard for the leader to say "I am your legal ruler by our Laws and the will of God, you must help to restore my rule over my godless, oath-breaker, usurper cousin, bla, bla, bla", and then break the feudal contract, with no military need, by building a pile of skulls from innocent peasants who were not hampering him in any way and are generally indifferent over which royal is the ruler. Besides, battles, looting, foraging, and post-war pestilence and famine already would kill peasants enough.
Comment: In that case, you were screwed. Hopefully your liege would avenge or compensate you.
Comment: From historical examples like Mongolian invasion: If a smaller or a whole region was killed off, generally (foreign) settlers came and become the new peasants. Since we are talking about an agriculture-based economy, recovery generally means rebuilding whatever left DIY style and working on the field and try to survive till the next harvest. Such mass migrations were one of the main reasons for the ethnic map in Central/Central-Eastern Europe.
Answer: Theoretically, his lord should help
Feudalism lasted a long time in many countries with different cultures, religions, natural conditions etc ... Therefore, any generalized and generic answer would be certainly lacking . That being said, let's give it a shot.
Basic relation between a lord and a vassal was granting a fief in return for a service. Vassal would swore fealty to the lord, promise to come to his aid in case of war (with or without number of men, depending on size of fief) , pay some taxes (usually) to the lord, sometimes to uphold laws of the realm and to protect state religion (church) etc ... Although fief was usually hereditary (especially in Europe) vassal was not strict owner of it. In fact, there is a number of cases where king would take away possessions of a treacherous noble and give it to another (for example James II took away lands of powerful Douglases ) .
In any case, fief was main source of income for a vassal, and means to fulfill his obligations towards a lord. Larger and richer the fief, larger were those obligations. Ruined and burned fief, with serfs slaughtered was not worth much. It would be akin to expecting same job commitment from an employee who's salary was severely reduced. Theoretically, it was obligation of the lord to help his vassal in time of need. One measure would be to move some serfs from lord's own lands to vassal's . Depending on the phase of feudalism, this could be done with or without serf's consent. Usually, they did try to give some incentive to serfs like larger piece of land, bigger share of the crop etc ... Of course, in some cases lord's lands would be also in dire straits. Lord could reduce obligations for his vassal (come with two men instead of ten, and bring 10 gold pieces instead of 100 ) . Of course, there were the cases with obstinate lords who didn't want to reduce obligations from their vassals, which led to vassal's revolt or working to death remaining serfs (and having them revolt) etc ...
In the end, it is worth mentioning that feudal political theory emphasized Noblesse oblige, or in other words that privileges that lord has over his vassals and surfs also entail his duty to help them and protect them in time of need. Of course, in reality that could be much different, but at least theoretically it would be the duty of greater noble to help those bellow him.
Answer: I am basically doing this from memory based on what I've learned over many years, so something I may be mistaken about, or misstate some things, or I could be confused and be dead wrong.
So I welcome anybody who spots the areas that I'm wrong or off  and corrects them. I'm not sensitive in that I do not know everything and I am welcome any corrections to what I will be saying below.
Medieval warfare was a long process of making war. There are at least three factors that we take for granted today that they did not have:
The first is communications. They had to send runners over land and in some cases overseas to find or communicate with allies or family members who married other nobles from other countries.
Depending how bad you were just devastated, the second factor is raising an army, and knowing how to train new members and even organize them on a battlefield. Back then it was done with flags and horned instruments, each with their own meaning.
And thirdly, since you had mentioned that most all your peasants were killed in the attack, you will need to recruit others to fight for you. Unless you're rich, or since the people who used to work the land had ownership like crop sharing (if you allowed ownership), you can use incentives such as fighting for you you give them a free house plus a stipend to help them get settled in your lands. Recruiting can take a very long.
And more than likely your crops were destroyed during the attack and you're gonna need people to work your land so that you can make money And feed your people from the crops you grow. So whoever you recruit will not only work the land, they will also be obligated to fight for you.
Now if you're a Knight or a Baron, these two ranks are on the low end of being royalty. In fact, the King or Queen can bestow Knighthood to anyone for any reason, and that does not entitle them to royalty benefits.
And most people earn the title of Knight by fighting for their Baron or Prince, and other royalty above them. You have to train in the fighting arts for many years, usually apprentice under another Knight, and be recognize for bravery in battle to become a Knight. So as a Knight you really are an elite fighter for whomever you work for.
Now a Baron is a landowner who owns one or more estates, and maybe has a castle, and lots of peasants working all his lands. When a Duke or Prince or other royalty above a Baron request that he joins in on a fight, he will enlist many of his peasants to fight for him, otherwise he will kick them and their families off his land.
If you were a Baron who were attacked and lost most of your peasants, and since you are part of the royal family, you will have a easier time recruiting people to both work your land and fight for you if called upon. Hopefully you have some Knights available to train your peasant Army.
One other thing that I recall is that Knights had to provide their own weapons and armor. That means they paid for it out of their own pocket. None of the members in the royal family gave them anything. Same thing with the peasants who you want to fight for you as a Baron.
Unless you are super rich and can provide the weapons and armor, you would require your peasants to provide at least a shoe ld, a sword, and some kind of rudimentary armor to protect their heads and body. But it will not be on the level of what a Knight wears or arms themselves.
Again, I made this post basically from memory of what I learned about Medieval war and who provides a lot and how peasant recruitment is done.
There are many other factors, and generally if you have a large family who are on the same level of you or higher, you can expect help from them in recruiting and training and possibly even providing you with soldiers. Here would make a difference because if you're fighting along side your family member, part of their army can become part of yours and both will fight together as a unit.
So if I made any mistakes or mis-stated anything, please Feel correct what I said. But I think I got the basic principles right, for to answer this question completely, there have been volumes of books written about the subject.
I hope this helps.
Comment: To start: you have conflated being a *knight* with being a *mounted man at arms*. Being a knight required being provided with sufficient income to maintain yourself, grooms, additional unmounted men at arms, archers, perhaps your older sons as mounted  men at arms, etc. Only a very poor knight would be arriving with less than 10 retainers as described above. Such a *knight's fee* was almost always a *manor*, but on occasion might be an office or appointment with attached income: perhaps constable of a castle for example.
Comment: @PieterGeerkens - The gray text indicates this was a WB user who doesn't have an account here, so they would appear to be quite unlikely to see any comment, or edit the answer. We're likely gonna have to take this post-as-is.
Comment: Now that the question has been migrated, I recommend correcting the substantial number of grossly incorrect assumptions and statements about feudal society. The answers [here](https://history.stackexchange.com/questions/53649/did-every-medieval-village-in-europe-have-a-manor-castle-or-other-type-of-lord/53680#53680) and [here](https://history.stackexchange.com/questions/42224/what-kind-of-education-would-a-12th-13th-century-english-knight-get/42228#42228) will give you a leg up, but there are many other fine answers on feudalism on the site as well.
Comment: For a peasant, having a spear would be more likely than a sword (much more expensive). Also, in many cases looting caused famines which killed more peasants than the war itself (or made people flee the land). The bright side is that, after the war,  a severely depopulated fief would have juicy land plots available, arable, fertile, near water, and this would make recruitment from nearby fiefs more likely. E.g. a friendly Lord could allow second sons of serfs to emigrate, as they would not inherit plots of land as serfs and would be more productive in the better, now vacant, plot of land.
Comment: Pieter, on this medieval music, the King ridicules some knights, who were supposed to bring five, seven, or eight companions, but did not bring them. https://www.universocantigas.gal/cantigas/o-que-da-guerra-levou-cavaleiros


Install sandbox solution to SPWeb

Question: I need to install a sandboxed solution to my site (SPWeb). However I am not a site collection administrator, and therefore cannot access the solution gallery that exists at the site collection level. I am a site (SPWeb) administrator though. How can I deploy my solution on the site (SPWeb) that I am admin of? Or do I have to ask the site collection admin to upload my .wsp to the site solution gallery for me?
Answer: You'll need to ask a Site Collection Admin to upload it for you if you don't have the right permission.

A sandboxed solution is installed by a site collection administrator
  to the site collection's solution gallery. This gallery also shows the
  current resource usage, average resource usage over the past two
  weeks, and the status of each sandboxed solution.

Sandboxed solutions overview (SharePoint Server 2010)
Comment: Yeah, I figured as much (and I also saw that documentation). I guess it can't be done using powershell either, since I can't access the server anyway. Btw, do you know of any way how I can tell what the URL is of the site collection?
Comment: A site-collection url will either look like:
"_http://www.mysite.com"
OR
"_http://www.mysite.com/sites/mysitecollection" (without _)
and "sites" can be replaced by other values...
Comment: The sitecollection usually starts either at the root / or one level below sites, but can be setup in Central Administration to start at any level.

Install sandbox solution to SPWeb


Check in multiple documents at once

Question: One of our users did a bulk drag and drop of many files while we had version control turned on.  Now they are all checked out.  Is there a way to check them all in at once?  We don't need any comments on these documents.
Comment: Can you clarify which version of SharePoint this is for? E.g., SharePoint 2007, 2010, 2013?
Answer: You can do so by selecing all documents (clicking on the left of each one), then from the ribbon in the "Files" tab, click "check in".
Answer: There are some solutions in this other question: How do I check in a LOT of files all at once?
You have options:

User interface
Powr Shell
SharePoint Designer
Other Tools

Hope it will be helpfull
Comment: I probably should have mentioned there were many folders and sub-folders.  When I click on the Folders the "Check-in" is greyed out.
I ended up taking ownership and then selecting all files in each folder and checking them in.

Check in multiple documents at once


can we use 8051 pin as Input and output at a time?

Question: is it possible to use 8051 microcontroller as input as well as output at a time? if i use particular pin as input and then how to make it as output as well.tell me please i born just now in microcontroller
Comment: Do you mean using the same pin as an input at one time, then using it as an output at a different time? Trying to do both at the exact same time would not make much sense... unless you're afraid your output line is getting overdriven by some external driver.
Comment: Think, how would you implement such a thing in a hardware? And how would you use it?
Comment: is it possible to write code that same pin act as input (i.e read something from input) and output the value what we have read on that pin by connecting led to it.??
Comment: @chakravarthimerugumalli You could do that by briefly turning the pin into an input, reading the value, and then going back to being an output. If it's done fast enough you would not see the blinking of the LED. You might need a driver for the LED depending on how the voltages work out.
Comment: if i write "1" to output pin then pulldown transistor is in off state.so ,its logic value(5) same as when i write the "1" to input pin.buffers in the port structure will differentiate the input and output ?? or Instructions will make that??
Answer: The original 8051 and 80C51 has so-called pseudo-bidirectional I/O pins- they are open drain, with internal pullups (some pins may require external pullup resistors). So, they don't have (or need) the direction registers you may be familiar with from more modern microcontroller families than the rather long-in-the-tooth MCS-51).
So to use a pin as an input you write a '1' to the particular bit and read the pin. Whatever is connected to the 'input' must be able to sink more current than the pullup delivers.
It is not possible to use a pin as an input if it is set to '0' (the pull down transistor is quite strong).
The source current capability of the pin when used as an output is limited to what the pullup can deliver (though there is a 'strong' source transistor that comes on briefly when the pin is switched from '0' to '1' in order to charge stray capacitance connected to the pin quickly.
Edit :
Here is the bidirectional port image which might help beginners and others like me who just added an image to this wonderful answer
Edit: The above is a simplified view that was added know my answer, I will leave it as it may be useful, but for a more complete view, check this more recent answer.
Comment: is it compulsory to declare the port pins as input or output at the beginning of program or can we declare any where we want? (inthe middle of the code can i initalize that pins as input or output)
Comment: You can change them at any time and as many times as you like, whether the pins are old-style pseudo-bidirectional or true push-pull CMOS bidirectional.
Comment: P.S. of course you should set them up *before* using them, normally at the start of your program, but you can subsequently change the mode as desired.
Answer: The older style 8051 microcontroller ports are not the same as other more modern microcontrollers which can often have mixed inputs and outputs on the same port. If I recall correctly the standard 8051 must have all pins of the same port either used as all inputs or all outputs, at any one time.


Changing Discussion Folder Names in SharePoint 2010

Question: Is there a way to change the name of a folder within the discussion area of SharePoint 2010? The folder by default is given the name of the discsussion name when it is created, however, if you then change the discussion name, it does not (quite rightly) automatically update the folder name - I would like to though.
Answer: This might be doable with a Workflow as folders in a list are essentially ListItems.
If not, then write a EventReceiver to trigging when an item is updated, see if the discussion name was updated, then attempt to update the folder name.
I'm assuming uses Internal Names under the bonnet to reference discussions, so all you're really doing is updating display names.
Answer: Open your site in explorer view and try to change.
Comment: I tried opening in Explorer to change title - it didn't work.


Moving Magento from server to server - Archive files too large

Question: As my e-stores are too big to zip and download everything, I want to know what folders I should download from the old server and move to the new Magento installation, in order to get it quickly up and running?
Answer: Generally speaking the only thing that gets really large on Magento is the media folder. The rest you can transfer easily by creating either a ZIP or TAR on the server.
In case you have access to SSH you can use the following command to create a TAR excluding the media and var directory.
tar -czf ./backup.tar --exclude=./media --exclude=./var ./

But if you're moving the database (with products etc) also you'll need the media directory as well as it contains the product images.
To transfer everything from one server to the other you can use the following if you have SSH access on both servers
scp -r -p /path/to/current/installation [user]@[serveraddress]:/path/to/destination

Comment: There is one dynamic bash script for backup magento db + files with many options, you may try that. FYI, I am using this script for almost every Magento project to take regular backups: http://www.blog.magepsycho.com/backup-magento-project-files-db-using-bash-script/
Comment: nice! I'll give that a try
Answer: I prefer to use rsync to do transfers
rsync -avz -e ssh /path/to/local/ email@example.com:/path/to/new/

I would also exclude if you don't want to copy all the extra cache files.
You can hit this command more than once and it will only copy new items the second time!
The last thing is to move the DB: I normally do a dump and restore then update your core_config_data table
Comment: Another advantage is the --progress switch, which ads a nice progress bar. With scp you just don't know when it will be finished.
Comment: Are there any more advantages to using rsync over scp? Anyway, I already like it better then scp :) +1
Comment: Once you've discovered rsync, you don't ever want to go back.
Comment: You can add excludes and exclude lists in rsync
Comment: @brentwpeterson never worked with ssh, but what is path/to/new? is it webserver public_html?
Comment: Basically you have rsync -avz -e ssh from/ to/
http://www.linuxmanpages.com/man1/rsync.1.php


Do I need to pay tax on the amount of savings I have in the bank?

Question: Do I need to pay tax for the amount which I have in the bank? If so, what's the tax percentage for a savings account and a current account?
Comment: @Victor, I generally would agree, but I know there are some very weird rules in India, so you never know...
Comment: You generally don't pay tax on money you have in the bank, you pay tax on any interest earned on that money.
Comment: Indeed, as Dheer's answer points out, there _is_ a tax on _wealth_ in India, not just on _income_ though there is a large exemption so that the majority of  taxpayers are not subject to it.
Answer: In India, assuming that you have already paid relevant [Income/Capital gains] tax and then deposited the funds into your Bank [Savings or Current] Account; there is NO INCOME tax payable for amount.
Any interest earned on this amount is taxable as per Income Tax rules and would be taxed at your income slabs.
Wealth Tax is exempt from funds in your Savings Account. I am not sure about the funds into Current Account of individual, beyond a limit they may get counted and become part of Wealth Tax. More details here http://timesofindia.indiatimes.com/business/personal-finance/Do-you-have-to-pay-wealth-tax/articleshow/21444111.cms
Answer: Not for the amount in the accounts but for the interest you earn per year is taxable. But the sum of your all taxable incomes is under the limit, then you dont need to pay any income tax. The limit is available at wiki here
But you should intimate your bank not to deduct TDS (Tax Deducted at Source) by submitting Form 15G/15H (which will be normally available in Bank itself), provided your total interest income for the year will not fall within overall taxable limits.
You may calculate your income tax amount at Official website at here


Geology/mineral dataset

Question: I'm looking for a dataset that relates the location of minerals or other valuable resources like gold or oil to the geological conditions in which they occur. So for example for a certain location, it could have the surface pressure, temperature, soil info, etc. Where can I find something like this?
Comment: Possible duplicate of [High Resolution Mineral Maps](https://opendata.stackexchange.com/questions/2072/high-resolution-mineral-maps)
Answer: You will most likely need to combine multiple datasets to get what you are looking for here. As mentioned in High Resolution Mineral Maps, you can find some of this information in the USGS Mineral Resources Data API, including mineral availability (by region, resource, or boundary) and some geologic and soil conditions.
The NOAA datasets, particularly the paleoclimatology datasets, may fill in some of the climate related data (present or historical) that you mentioned.
You may also find the Global Lithological Map (GLiM) from Hamburg University's Institute for Geology useful for surveying geologic conditions.
Comment: I haven't checked for existing libraries that wrap one or both of these sources -- additions or edits welcome on that front.
Comment: Using an API is a little inconvenient because I'm going to be building a machine learning model. Any alternatives?
Comment: Unfortunately those are proving hard to find. Added GLiM to the answer, which may help you a bit.
You mentioned specific commodities (gold, oil) -- MRDATA has datasets that you can download on specific commodities, but finding them is a challenge (they don't all appear to be grouped together, though https://mrdata.usgs.gov/major-deposits/ may help.)

Geology/mineral dataset


What is a "period" of the periodic table?

Question: I'm familiar with the periodic table / periodic system, but I wonder why it's called "periodic" since there seems not much periodic about (there seems to be little or no predictability of which elements are stable) and from physics I know Z-value of elements and that is not periodic either. So what is a "period" in this context?
Answer: I agree that the "periods" in the periodic table are not mathematically regular.  The simplest definition is that a period begins when a new s-subshell starts to fill.  Recall that in the s, p, d, f subshells there are 2, 8, 10, and 14 electrons, respectively, so the periods have to get bigger over time and thus cannot be regular.  As to the lack of predictability of stability, that may be true, but the periodic table is pretty good at predicting the chemistry of elements by collecting together similar elements into groups (the columns).  This similarity is mostly expressed by the s and p subshells, which is where a lot of the reactivity occurs.
Comment: When it started it was periodic and the name never changed.
Comment: You could also consider a more general definition. The period in a very general sense is a group of elements after which the chemical properties begin to repeat i.e. the elements coming after each period can be arranged in a way that elements in the same vertical column (group) have similar chemical properties. In the periodic table, the periods change in a regular manner (a new block is added after every two periods, etc)
Answer:
So what is a "period" in this context?
  To answer this directly, a period is a row of the table.

As user467 indicates, the repeating periods reflect the filling-up of atomic orbitals. Because the valence electrons (those in the outer shell of an atom) determine many of the chemical properties, the periodic structure places atoms with similar valences in similar groups (vertical columns.)


Bike chain too long?

Question: Recently, my road bike's chain got cut, so i took it for replacement. A new chain was inserted and the shifting had a good transition. However, when i shift on the harder gears, i hear "crack crack noises" as if the chain is not well fit. I returned it to the repairman who still said he now fixed the problem but i still have the same issues. It seems he only tested the bike while suspended but not on actual ground. Is this because the new chain was too long ?
Comment: As @Blam points out, your cassette is most likely worn. The venerable Sheldon Brown has a [wonderful article](http://sheldonbrown.com/chains.html#stretch) about how chains and rear cogs wear together and then everything goes to pot when you replace the chain.
Comment: To answer your specific question, the chain length can be calculated, and whether or not the bike is in a stand should make no difference. It would be helpful here if you knew what the repairman had tweaked in order for him to say he'd fixed the problem
Comment: @PeteH Length may be the same on the stand or not.  But force is factor on chain jump on a worn cog.
Answer: You probably need a new cassette/freewheel. A new chain on a worn cassette will jump (especially on the harder gears).
The harder gears have two things going against them.
Less points of contact to share the load.
Less points of contact so they tend to be worn the most.
If you have front derailleur then using the bigger ring there will let you use bigger cogs in the rear.  If I can be in 3 or higher in the rear on the big ring up front then I use the big ring up front to keep miles off the smaller cogs in back.
Comment: If you keep riding, the new chain will rapidly wear down to match the wear on the cassette/freewheel.
Comment: Can replacement be avoided by adjusting the bike shift to only 1 speed ? I am not financially sound now.
Comment: On the cassette/freewheel different cogs will be worn to different extents.  If you stay on the less worn you will get less (or no) skipping.  And once the new chain stretches it might start working on the harder gears.  Save up and next time get a chain and cassette.

Bike chain too long?


Using web scraped data for consumer price indices

Question: Is there information and literature regarding comparative consumer price index methods? Specifically, the web scraping method of index construction?
Answer: Take a look at Billion Prices Project:

The Billion Prices Project is an academic initiative that uses prices
  collected from hundreds of online retailers around the world on a
  daily basis to conduct economic research.

Also take a look at PriceStats

PriceStats collects online prices to provide daily inflation updates
  for 22 economies.

Overview of the PiceStats approach
More broadly, price index construction is a huge literature full of pitfalls so it is difficult to point you to a generic but also advanced presentation of the issues. But you might start with Consumer Prices, the Consumer Price Index, and the Cost of Living (Boskin, Dulberger, Gordon, Griliches and Jorgenson (1998)), a Journal of Economic Perspectives piece on the subject.
Comment: Hi, I am working on a project comparing international uses of web scraping to compile their respective CPI's. Would you happen to have any leads regarding this? Thank you
Comment: Also would you happen to know how to program such web scraping programs to help me test them? Thank you
Answer: In Spanish you can reach IPC Online project in Argentina. https://ipconlinebb.wordpress.com/


What plant has no foliage and clusters of red berries on top of a fleshy 1' stem?

Question: I have strange plants growing among my redcurrant/raspberries and close to cobnut trees . They have a single fleshy stem, no foliage, are about a foot tall and have a cluster of bright red berries at the top 2-3 inches of the stem. I had thought that they were some sort of fungus, however they have roots like a small rhizome and are also in clusters. What are they and could they be harmful to the other plants nearby? The redcurrants have been poor this summer, and one bush has had to be dug up and destroyed.
Comment: Welcome to the site and thanks for the description of your plant! Could you please add a photograph to your post as it could make identification much easier and definite? Also, adding your location may help narrow down the possibilities if there are several close matches. Thanks!
Comment: Can you post a photo and tell us where you are located? They sound similar to Jack-in-the-Pulpit plants, but I have no idea if that is a possibility where you live.
Answer: Most likely Arum - Arum maculatum or Arum italicum in particular. Common names include Cuckoo Pint, Lords and Ladies in the UK, with other common names in other parts of the world. They do have leaves earlier in the year, which you may not have noticed, but by the time the berries form, the leaves have all died back. Contact with any part of the plant may cause an allergic reaction in some people, but only the berries are toxic - said to be highly so if ingested, though there is some argument about that. The berries contain something that makes consuming them like eating needles, so most people never eat enough to be killed, though swelling of the mouth and tongue might mean they asphyxiate.  They're commonly found in association with trees, and in disturbed soil (disturbed can mean simply cultivated). The only thing that gives me pause is the height - usually, the stalks with the berries clustered around are about 6-8 inches in height. Be good to see a photograph. There is no evidence that they are allelopathic, though the presence of this plant in quantity could mean deprivation of nutrients and water to your other plants in the area.
Pictures of A. italicum:
Fruits:

Leaves:

Pictures of A. maculatum:
Fruits:

Leaves:
Comment: That's what I'm thinking. Especially *A. italicum*.
Comment: @Allan In that case, proper stack exchange etiquette would be to mark the answer as accepted, so that it can better help other users. :)
Comment: @Allan, Do you think it is *A. italicum*, or *A. maculatum*?


What PPI and DPI is needed for a photographic backdrop printed at 6x4 foot?

Question: What PPI and DPI is needed for a photographic backdrop printed at 6x4 foot? I have a stock image which is 4000 px across and 300 dpi. Do I need to enlarge that with photoshop before sending to my backdrop printer?
Comment: When in doubt, always ask your printer.  It's hard for us to really give you a definitive answer, without knowing all the details of their printing process, but I think that the image is high enough resolution to work.  Make sure you send them an uncompressed .tif, for any raster images involved.
Answer: I would use between 72-100 dpi if the image could handle it, although you could maybe drop it down a little further if necessary. .
The longer the distance you view something, the smaller the dpi, at longer distances a higher dpi is wasted. So general rules would be.
Magazine (close up) 300dpi
Banner (medium distance) 72 - 100dpi
Billboard (long distance) 30 dpi
My biggest piece of advice is always best to ask your printer, an experienced printer will always help you get the best possible results.
Check out this previous answers for a little more detail.
Comment: If the stock image on-hand is the only option, then the truth is, the OP should submit it as-is without modifying it (aside from the appropriate cropping), and then ask the banner-maker to print it at the specified size. There isn't any benefit to the OP resampling the image prior to that. As you say in the linked answer, the banner people are only going knock it back down to (*foo* ppi). The main concern is how is the banner going to re-photograph, and it sounds like you have experience with that.


What is the origin of the word "copped"?

Question: In the language used by footy (Australian football) commentators the word "copped" is frequent. For instance, if a player gets knocked on the head, say, then the sentence might be "player X copped one". I never heard this expression in Britain or the USA. Is it a specifically Australian word? And where does it come from?
Comment: What research have you attempted prior to asking here? What results have you gathered that were unconclusive?
Answer: It's used quite a lot in British English.  The verb "cop":

1.1 Incur (something unwelcome):  'England's captain copped most of the blame'

In your context, you could say "Player A copped a knock on the head".
Interestingly, you can also receive something welcome by "copping" it:

I copped myself a bottle of champagne in the raffle

Regarding etymology:

early 18th century (as a verb): perhaps from obsolete cap 'arrest', from Old French caper 'seize', from Latin capere
Comment: In the US one would "cop a plea" when confessing to a crime.  I suppose it originally meant accepting a plea bargain and so matched the above sense, but that sense has been largely lost, I suspect.
Comment: Cop a feel is also strange expression
Comment: It basically just means **take**. It's that simple.
Comment: This is also why police are called cops or coppers.
Answer: Back in  colonial times  before the late 1800s andFederation ,  when Australia wasGoverned  and policed by the corrupt  New South Wales Corps (a.k.a. The Rum Corps)  Rum Corps was comprised of .....Due to the remoteness and unpopularity of the posting, the New South Wales Corps were composed of officers on half pay, troublemakers, soldiers paroled from military prisons, and those with few prospects who were gambling on making a life for themselves in the new colony.
     The colony, like many British territories at the time, was short of coins, and rum soon became the medium of trade. The officers of the Corps were able to use their position and wealth to buy all the imported rum and then exchange it for goods and labour at very favourable rates, thus earning the Corps the nickname "The Rum Corps". By 1793 stills were being imported and grain was being used to make rum, exacerbating the shortage of grain.
             These  extremely corrupt militia /  early police  were renowned for dishing out there form of punishment to  convicts & settlers alike   eventually  leading to  terms like -... I copped a beating from  the bastard rum corps  ( other Nickname(s)for the Rum Corps were ; Botany Bay Rangers, Rum Puncheon Corps, The Condemned ).
             Or - ... I copped one in the goolies , thanks to thepuncheon corps` .


What is the logic the Fed used for paying interest on reserves?

Question: During the last few years, the Fed has been paying banks interest on reserves. Its a strange policy if you want banks to invest their money in the real economy. Why did they do this? Is it a way to recapitalize the banks? Is it a way to guarantee their solvency irrespective of the availability of investment opportunities? Is it a way to limit the potential inflation of QE?
Comment: Some points are raised here:
https://en.wikipedia.org/wiki/Excess_reserves#Interest_on_excess_reserves
Answer: According to Bernanke himself, interest paid on reserves in excess of the penalty free upper bound are used as an additional tool with which the Fed can place a floor on the federal funds rate.The logic here is that banks have no incentive to lend in the overnight market at rates lower than this interest rate.
This link has some links to info on the topic. It's an old answer that got little attention and so here is my chance to get some use out of it :)
Federal Reserve Interest
Answer: The aim of this policy (introduced in 2008) was to "give the Fed better control of the short-term interest rate" via reducing the demand for short-term government bonds by taking out some of the excess cash that banks hold.
In a crisis, banks are not lending, and thus the cash they have is poured into many assets, including short term government bonds. This reduces the market short-term nominal interest rate. To control for this, the Fed has to sell some of their T-Bill holdings in order to reduce the money supply. Yet, the intervention of the Fed are more precise if the amount of cash willing to participate in that market is smaller. That is why offering banks an incentive to gain a return by parking part of that cash into US regional Central Banks helps to lower that demand.
Certainly, this policy also helped banks to build up their assets. However this has been a relatively very minor issue, according to a recent inlet in The Economist (March 18th). The graph is below:

There is some opposition to this policy though. On the one hand, some say it reduces bank lending. On the other hand, as the graph show, the official forecast for the interest paid on these reserves is likely to increase considerably in the coming years, mainly because the Fed is now increasing the interest rate. Politically, this is a hard-seller, albeit Trump might not be very worried about this. Who knows.


Show Non-Steam games as Steam games?

Question: So I was wondering if I could show Non-Steam games as Steam games, such as if I buy GTA V on a DVD, install it, and add it to Steam. I would like it to show GTA V as a Steam game for screenshots and all that, but how? I know Steam has the games I want to do this with but I don't know how to get them to show up as Steam games.
Comment: I don't use Steam, but I'll help you clarify your request.  What all do you want to achieve by showing GTA V among the games which you installed via Steam?  It is most likely that the ability to add games to the Steam dashboard is simply an attempt to keep you inside their interface while you play your games — less likely that there is any way to gain access to Steam functionality if something does not include whatever support or modules are required to use that functionality.
Comment: @JonathanDavidArndt What did you just edit in this question? It says two characters were added to the body, but I can't discern them in the history. Also - but this might be related - why did you edit a question that was closed 3 years ago?
Comment: To undo my vote. (You can rollback the edit if you wish.)
Comment: @JonathanDavidArndt I get why you'd want to do that, but it feels like cheating the system (especially since this question features your answer, which you bring attention to this way).
Answer: From the Steam desktop client, in the lower-left hand corner, there is a link that reads:
+ ADD A GAME...
Clicking this link presents you with an option to Add a Non-Steam Game.
You can select from a list, or browse to any executable file on your hard drive.

Additional note (contributed by Asunez)
Doing this only adds the program to your local Steam library. Logging onto the same account on another computer will not restore Non-Steam games to the list. Also there is no Steam Cloud backup, and no support for community sites. If the game is online multiplayer, all Steam invite-theme operations will not work, either (no joining servers, no inviting friends, no party/lobby).
All Non-Steam games are somewhat impaired, and while you can save screenshots, and others can see you are playing the game, it is not the same as purchasing the same title on Steam.
It's basically adding a shortcut to a program, and making Steam overlay work in that Non-Steam game.
Comment: After a mere 60 seconds of work with the Snipping Tool, this is currently my highest ranked answer - higher even than others which took much experimentation, research, and lots of (admittedly fun) playtime. That's almost embarrassing.
Comment: It is being upvoted simply because what OP is asking is impossible. The game that has been bought on retail specifically states that it is for a rockstar profile, steam integration as a steam game (joining trough steam, achievments and such) never work this way unless valve decided to include the cd Keys to their own pool, like with old retail copies of warhammer 40k dawn of war. Many, many newer games do not allow this, particularly ones that are natively on different platforms like U-play or rockstar's (this is the reason these are sold for lower prices online than their steam counterpart)
Comment: I specifically asked on how to get it to show up as a steam game, not a non steam game as anyone could Google this in 30 sec.
Comment: @ChristoferMinestar Yes, it baffles me why this answer is being upvoted.

Show Non-Steam games as Steam games?


Does the network number in IPv4 addresses refer to networks that make up the Internet?

Question: I'm reading that IPv4 addresses consist of a network number and a host identifier.  Is it accurate to say the Internet is a collection of networks, and this "network number" refers to just one of these networks? For example, a college campus might be such a network.  Or a city-wide ISP might be another network.
Answer: Version 4 of the Internet Protocol (IPv4) defines an IP address as a 32-bit number. However, because of the growth of the Internet and the depletion of available IPv4 addresses, a new version of IP (IPv6), using 128 bits for the IP address, was developed in 1995, and standardized as RFC 2460 in 1998. IPv6 deployment has been ongoing since the mid-2000s.
A public IP address, in common parlance, is a globally routable unicast IP address, meaning that the address is not an address reserved for use in private networks, such as those reserved by RFC 1918, or the various IPv6 address formats of local scope or site-local scope, for example for link-local addressing. Public IP addresses may be used for communication between hosts on the global Internet.
So in accordance to your question, a public IPv4 network number could be an ISP, where the host identifier, could be a customer with an internet connection rented from that specific ISP.
Companies can also own public IPv4 networks, where the single public IP addresses within those networks are the host identifiers.
Answer: The answer is Yes, but the same network can be seen in different sizes, depending on where you are in the network.
Comment: Keep reading your book. Your getting there. It's more complicated but your on the right track.


What gate should one use to perform $R_y$ using a single $R_z$ + Clifford gates?

Question: I know how to perform Rz rotations with the least amount of T gates, eg by using Efficient Clifford+T approximation of single-qubit operators by Peter Selinger. Similarly, one could use H Rz H to perform an Rx rotation. This seems to me like a simple question, what gate should one use to perform Ry using a single Rz + Clifford gates?
Answer: The phase gate $$S=\begin{pmatrix}1&0\\0&i\end{pmatrix}=\sqrt{\sigma_z}$$ satisfies $$S\sigma_x S^\dagger=\sigma_y,$$ where $\sigma_i$ are the Pauli matrices. So, once you know that $R_x=H R_z H$, you can immediately find $$R_y=SH R_z HS^\dagger.$$
You can also do $$R_y=-S^\dagger H R_z HS.$$
Comment: Have you mixed up your subscripts on the last couple of lines? ($R_x=HR_zH$ and $R_y=SR_xS^\dagger$? (Note, also, that I don't think you need the -ve sign)
Comment: Thanks a lot for your answer! I am confused by something though, if $S = \sqrt{\sigma_z}$ then doing $S R_z S$ should make $R_z$ commute with $S$ and therefore the result is diagonal, which need not to be $R_x$.
I think what you meant is
$$S^\dagger R_y S = R_x$$
(I've checked it computationally). Had not seen the previous comment, sorry.
Comment: Major typos, sorry about all of that - edits should suffice
Answer: There's a bunch of single Clifford gate types that you can use.
$R_y(\theta) = \sqrt{X} \sqrt{X} \sqrt{X} R_z(\theta) \sqrt{X}$ where $\sqrt{X} = HSH$ is a 90 degree rotation around X.
$R_y(\theta) = C_{XYZ} R_z(\theta) C_{XYZ} C_{XYZ}$ where $C_{XYZ} = (iI + X + Y + Z)/2$ is a 120 degree rotation around X+Y+Z.
$R_y(\theta) = H_{YZ} R_z(\theta) H_{YZ}$ where $H_{YZ} = (Y + Z)/\sqrt{2}$ is a 180 degree rotation around Y+Z.
There's no Clifford gate $U$ with the property that $U R_z(\theta)$ = $R_y(\theta)$. This is obvious because $Y$ basis interactions should commute with $R_y(\theta)$ but when crossing $Y$ over $U R_z(\theta)$ the $R_z(\theta)$ moves the $Y$'s rotation axis to something arbitrary (not a Clifford operation anymore) and a Clifford $U$ can't get it back to where it should be.
You can also do it with two qubit gates. E.g. if you have an ancilla in the $|0\rangle$ state:
$R_{Y_{target}}(\theta) = \text{Control}(Y_{target}, X_{ancilla}) R_{Z_{ancilla}}(\theta) \text{Control}(Y_{target}, X_{ancilla})$ where $\text{Control}(Y, X)$ applies an X to the target when the control is in the $|-i\rangle$ state.


The Warm Oven Temp. for Cakes

Question: My Mom is making a cake. Its an old recipe, 50 - 70 yrs old (or older). All it says is to use a warm oven. No temperature range, just a warm oven. What temperature would this be?
Comment: Do you have any more information about the recipe? What are the ingredients?
Answer: Without any details on the recipe, it is hard to offer any firm recommendations. That said, I have had success using a convection oven on 180 degrees Celsius (356 degrees Fahrenheit), and checking for doneness with a bamboo skewer.
Comment: +1, I have yet to see a standard cake for which 180 convection is a bad temperature (there are pastries which need it hotter, but they are not usually called "cake").
Comment: I think any recipe old enough to only mention "warm oven" will not anticipate convection.
Answer: For some cakes, I bake longer at 300F, and the result is quite delicate.

The Warm Oven Temp. for Cakes


Time based Workflow in combination with recipient change

Question: This is basically a design question. I have a field (lookup to User record), called Recruiter__c. And lets say there is checkbox field that acts like a criteria for a WF. Lets call it Send_Reminder_Email__c checkbox field.
This is my requirement- Whenever Send_Reminder_Email__c is checked, send an email to "Recruiter_c" right away (using email alert action), and also have a 24 hr reminder, which can be accomplished by adding a time based action (an email alert) on the same WF. If after 24 hrs, Send_Reminder_Email__c is still checked, send another email (and that would be it, no third reminder).
This is easily doable. But now the ask is to make sure we kick off the WF again when value of field Recruiter_c (which is the intended recipient of email alerts) changes.
I am unable to find a design to marry those two criterias.
While creating a WF, if i select "When record is created and every time its edited", i can use ISCHANGED function in formula for criteria, that will help me detect changes to field Recruiter_c. But it doesn't allow time-based Wf actions.
Now if i chose "When record is created and every time its edited to meet the criteria", i can have immediate as well as time-based actions, but now i can't use ISCHANGED function, so no way for me to incorporate changes to Recrutier__c field in Wf criteria.
Using process builder has same issues.
Can anyone suggest me any design to solve this? Even if it is combination of code and declarative features.

Update as per recommendation of sfdcfox (but still not working)
So i added a checkbox field "Control_Flag_for_WF__c", default state of field being TRUE. We effectively turn it off and on again, in conjunction with other rule criterias, to fire the email WF again. I have total of 3 workflows, out of which two are dedicated to turning the control flag off and on again when change in "Recruiter" is detected
Workflow 1
when to fire = When a record is created and every time its edited (this is when we can use ISCHANGED function)
criteria = ISCHANGED(Recruiter__c)
Immediate action = Field Update, Control_Flag_for_WF__c = False
In field update, i have selected "Re-evaluate WF rules after field update"
Workflow 2
when to fire = When a record is created and edited to meet the criteria
Criteria = Control_Flag_for_WF__c = False
Immediate Action = Control_Flag_for_WF__c = true
In field update, i have selected "Re-evaluate WF rules after field update"
Workflow 3 (the actual Wf that sends email)
When to fire = When a record is created and edited to meet the criteria
Criteria = (Control_Flag_for_WF__c = true)  && (other relevant criterias)
Actions = Immediate and a time based action to send email
Workflow 1 and 2 work. But workflow 3 never fires. If i test WF 1 and 2 in isolation (deactivate Wf 3), they work .. which means when Recruiter__c is changed, the control flag is set and reset. If i deactivate WF 1 and WF 2, and manually uncheck and check the control flag, it fires WF 3. But somehow when i put all of them together, WF 3 doesnt fire
Answer: I believe you can do this, but you need three rules/criteria. In both cases (workflow/process builder), the first rule/criteria fires when the recruiter changes, and unchecks the checkbox. The second rule/criteria fires when the box is unchecked, has changed, and the recruiter has changed, and its purpose is to check the box again. Finally, the third rule/criteria sends the immediate email and schedules a time delay email 24 hours later. The process builder would need to allow recursion (the Advanced setting on the object selection box), while the workflow field updates need to reevaluate rules.
Comment: sounds fantastic. Let me try it out and come back here to give the updates. But i think it will work. Thank you
Comment: Doesnt seem to be working (it should, your idea was excellent). I am about to post an edit to my question. Let me know if you see what am i doing wrong. Thank you for your help


How does auto.arima deal with the a leap year in R?

Question: For data at a weekly level, I'm giving frequency as 52 for the auto.arima function. What happens when a year has 53 weeks? How does it affect the forecast?
Comment: Leap years don't have 53 weeks. Nor do ordinary years have 52. Ordinary years have 52 weeks and one day while leap years have 52 weeks and two days. So if it does anything to deal with the fact that a year isn't a whole number of weeks, it has to do it for every year.
Comment: Thanks guys. It doesn't matter if Leap years actually have 53 weeks or not. But the data that I have has 52 weeks for an ordinary year and 53 for a leap year. I am just trying to understand how it might affect my forecast if I have 53 weeks of data somewhere in the dataset for a year and the frequency given is 52. Does it affect the seasonality in anyway?
Answer: You need to create a variable to account for the leap year effect.
For example, a common specificacion with monthly data is to define a column vector with zeros for all months except February. In February, the variable takes on the value 0.75 if it belongs to a leap year and -0.25 otherwise. In this way the leap year effect cancels out over a period of four years and does not affect the mean over this interval.
For weekly data, you could collapse weeks 52 and 53 into a single week (e.g. adding up the values for weeks 52 and 53 of leap years) and then define a dummy that could account for the different number of days in the last week of the year. Following the same idea as above, you could define a dummy with zeros for all weeks of the year except for the last one, which can be set to 0.75 if it belongs to a leap year and -0.25 otherwise.
There may be several other possible specifications for this variable. Regardless of whether it is a leap year or not, the last week of the year does not always have the same number of days. A dummy based on the number of days in the last week may be better, as it
may capture the potential effect of the length of the last week both in leap and non-leap years.
Once the dummy has been chosen and built, it can be passed to stats::arima and forecast::auto.arima through the argument xreg. When forecasting, remember that you need to extend this dummy for the out-of-sample periods.
Answer: Unfortunately, auto.arima does not seem to pay any attention to leap years. Thus if your data spans more than a few years, the 52-week frequency starts being a problem. You are getting out of sync at a pace of approximately one week every 5-6 years.
As regards seasonality, the first time "week 53" is encountered in your data, it will be treated as week 1 (because your specified frequency is 52), then the subsequent "week 1" will be treated as week 2 etc. The discrepancy will persist and even grow with every new "week 53".
Here is a useful treatment of weekly data by the author of the forecast package and the auto.arima function. It might help you solve the underlying problem.


What were Ares's powers?

Question: Poseidon, God of the Sea - water powers
Zeus, God of lightning - lightning powers
Hades - God of the Underworld - devilish powers
But what about Ares? Is he good at fighting? Can he summon swords at will? What is a "war" power?
Comment: What has your research shown you so far? Where have you already searched? What did you find?
Comment: https://www.theoi.com/Summary/Ares.html
Comment: All the pictures I see him in he has fire surrounding him I know fire is like Hephaestus power but maybe Ares share the same powers.
Answer: Well he's not a strategist, that's Athena.
I think it's fair to say Ares is a good fighter. But he's not the best- he's lost to Athena, and he has been on the losing side of a war as well. And that doesn't mean he's literally anything else - he runs in the face of battle, he sneaks around with Aphrodite behind her husband's back, he is hot headed and impetuous and bloodthirsty. He's a warrior who's a step above a barbarian(he represents the violent and bloody aspects of war), not a general (Again, that's Athena, she's not goddess of wisdom for nothing), or even a great warrior like Hercules, who did his Labours to atone for his crimes.
Ares is usually portrayed in a less than flattering light, and is frankly a bit of a bloodthirsty flake. Deimos and Phobos, Terror and Dread, are his attendants, without military strategies could be planned like chess strategies, because your men would never cut and run in the face of battle.
You could possibly extrapolate based on his children(Deimos and Phobos being the most commonly and closely associated with him), but he's not a DnD character. It's not a case of every god having a signature spell to summon something that represents them.
Answer: He doesn't exactly have a "power" like some of the other gods do. Zeus, Hades, and Poseidon have powers like that because they rule parts of the world, with Zeus as king of the sky, Poseidon ruling the oceans, and Hades as king of Erebus, or Hades, the Underworld. Ares isn't really portrayed as being very smart, he is very much a brutish, bloodthirsty warrior. He is a very good fighter, although he isn't good enough to win every fight. Like fifthviolet says, he's portrayed pretty negatively.He's a coward, and hates losing. He has a temper, and doesn't think before charging into battle. He has lost battles, but they were only to people who were smarter than him. In a fight of brute force, he could probably beat almost anyone.
So, yeah, he doesn't really have specific powers like Zeus and his brothers. I suppose he might have the power to make people want to start a war, but that's just speculation. If you need specific powers for some reason, like you're making a DnD character, he could have fire powers since he does have fire breathing horses, and fire can be rather consuming and destructive. Or he could just be an over powered fighter. Sorry if this was more than what you wanted and/or didn't really answer the question well. Hope it helped at least a bit, though!

What were Ares's powers?


2010 Chevy Malibu

Question: My center brake light worked with no problems, but then I had my brakes changed and now the center brake light now works sporadically.  What could be the problem.
Answer: This is most likely a separate fault that just happened to occur now.
If the other brake lights are functioning correctly, then the fault lies with either the wiring to that lamp, a loose connection in the wiring or an internal fault in the lamp.
If the other brake lights also mess around, check the switch and wiring.
Edit : as GdD has pointed out, the only common point is the brake pedal, the rest of the systems are separate.
Comment: Agreed. Brake lights are on a completely different system from the brakes themselves, the only thing they have in common is the brake pedal. When you push down on the pedal a sensor detects it and activates the tail lights.
Comment: @GdD good point, borrowed part of your comment!
Comment: Borrow away @SolarMike. Not sure it the malibu has the 3rd light on the trunk lid, if so the most likely point of failure's the wiring loom that goes up one of the lid arms.

2010 Chevy Malibu


water in redox reactions

Question: why water can't react as anode , with metals , in a redox reaction?
while studying electrochemistry, i passed through a table with certain metals , all having voltage (potential energy) less than water, which can react with water in redox reaction. in this case, the water react as oxidation agent.
my question, is why water cant react as reducing agent, with metals having potential energy bigger that it?
Comment: Water surely can and does react, given the right conditions. Could you please be more specific?
Comment: i will state from my lecture slideshow:
metals will react spontaneously with water if their E is less than -0.83V
my question is why ?
why a metal which has E>-0.83 V can't react with water?
Answer: Water can react as a reducing agent. However, you would have to look at the oxidation equation for water, which has an electrode potential of 1.23 V. If you wanted water to act as a reducing agent, you would have to react it with a metal whose E > 1.23 V. The equation that you are referring to (where E = -0.83 V) is the reduction of water. Therefore, you can only use it when you want water to act as an oxidising agent.
A note about spontaneity; it only refers to whether a reaction is likely to occur without any addition or removal of energy. In other words, the reaction would occur if the chemicals were brought in contact with each other. It does not mean that the reaction is impossible, because if you provided sufficient energy, the chemicals would react. This is usually supplied via a change in temperature. The reason metals whose E < -0.83 V react spontaneously with water is because the nature of the Gibbs free energy change (ΔG). For redox reactions, ΔG = -n x F x E cell where n is the moles of electrons transferred in the reaction, F is Faraday's constant and E cell is the cell potential. Reactions are spontaneous if ΔG is negative, meaning that E cell must be positive for the reaction to be spontaneous. When you add the half cell equations for metals whose E < -0.83 V and that of water, you get a positive value for E cell. Additionally, redox reactions are based on the idea that more reactive metals displace less reactive ones from compounds. Metals above water are reactive enough to displace hydrogen from water. Metals below water are not reactive enough to displace hydrogen and so cannot react spontaneously.
Answer: Water cannot act as a reducing agent to metals, simply because of the fact that metals do not react as oxidants, however metal-ions do. Below the values of the data of the standard electrode potentials (and the source site -- Wikipedia) is shown. Water is highlighted.
Data of standard electrode potentials
The table is sorted so that the strongest oxidants are placed highest in the table. As you can see, above water as a reductant, there are no metals reacting in half-reactions as oxidants. There are some metal-ions that would react as an oxidant. The reason behind why metals don't act as an oxidant, is probably because of their low electronegativity. The high electronegativity of some elements prevents them from becoming positively charged, and in a similar fashion, the low electronegativity of a metal prevents it from  becoming negatively charged.

water in redox reactions


Where can I get the required permits for Machu Picchu and Huayna Picchu?

Question: I've heard that I should buy a permit to visit Machu Picchu and Huayna Picchu. Where can I get them? (I've emailed to mtsobek.com travel agency, but there is no response from them). So if there is no way to do it by yourself (online?) then could you recommend any travel agency which may buy the permits on my behalf?
Comment: I called the travel agencies... you don't need an special permit. Just buy the ticket. If you need any further help just tell me I live in Peru and I'm willing to help :)
Answer: Unless you are planning being there outside of opening hours or for a purpose other than tourism, that is not the case.
When entering the reserve, you buy an entrance ticket. They are valid for one or two days. There is no need to acquire this ticket in advance, doing so at the main gate is typical. Some travel agencies, at least those in Peru, may be able to supply the ticket in advance. If memory serves, I've seen it done a few years ago.
Upon entering, it is a short walk to Machu Picchu and a steep trail up to Huayana Picchu.
Answer: Even if you're with a tour group, you almost all enter at the same point, and will be buying tickets at the gate.
It's important to note that while there's generally a few thousand a day at Machu Picchu, they severely restrict the numbers each day for Huayana Picchu.  So if you want one of those (2x200 I believe), you need to make sure you're on the first bus up there, or speak to your tour guide about getting there early.  Fight for it if you have to - it's totally worth it. As @Itai says, it's steep, and take insect repellent (never been bitten so much in my life) but the view from the top is totally worth the climb :)
Answer: One can buy a permit to visit Machu Picchu on https://www.machupicchu.gob.pe/inicio

For more information, see https://www.ticketmachupicchu.com/how-buy-entrance-machu-picchu-advance/#how_buy_machu_picchu_2020_ticket  (mirror).


Communication between VDCs on Cisco Nexus 7000 via virtual interface

Question: Is there any way to create a virtual interface of sorts between two VDCs on a single Nexus 7000 switch?  I've read that a physical cable is required (which is lame) however I wasn't sure if this was a feature that was added in a newer NX-OS release.  I'm currently running NX-OS v6.2(14).
Comment: Did any answer help you? if so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer.
Comment: Did any answer help you? You should accept an answer if it in any way helped you out, so that others can get help too.
Answer: There is no way to do what you want to do. VDCs virtualize control plane and data plane in protected memory so that each is an independent virtual device, just like independent physical devices. You can, of course, ask Cisco to consider adding this feature in a future NX-OS release.
From Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide:

Communication Between VDCs
The Cisco NX-OS software does not support direct communication between
  VDCs on a single physical device.
  You must make a physical connection from a port allocated to one VDC
  to a port allocated to the other VDC to allow the VDCs to communicate.
Answer: Physical cable is required. It's security function.
As Ron Maupin said, you can ask TAC to submit a feature request but I think you're going to have a hard time making a business case for it.


How much does an CGAffineTransformMakeRotation() cost?

Question: Is that an very cost-intensive function that sucky my performance away under my feet? I guess they used that one for the waggling buttons on the home screen + core animation. I just want to know before I start wasting my time ;)
Answer: Seems unlikely that it'd be much of a performance problem - it works out to something like a Cosine, a Sine, and a few multiplications. Don't call it thousands of times a second, and you'll be fine.
Answer: Very (very) little. This is also something you can easily measure yourself; see the following URLs for examples/information on implementing high-resolution timing:

http://developer.apple.com/qa/qa2004/qa1398.html
http://code.google.com/p/plinstrument/source/browse/trunk/Source/PLInstrumentTime.h
http://code.google.com/p/plinstrument/source/browse/trunk/Source/PLInstrumentTime.m
http://code.google.com/p/plinstrument/
Answer: Like with everything, it depends on how and how much you use it. It's used all the time in game development, which the iPhone is very well suited for. CoreAnimation is also very fast. If you're worried about it, my suggestion is to take one of the Apple-provided sample apps and run it through Instruments to preform some of your own benchmarks to see if they are acceptable for your needs.
Answer: All CGAffineTransformMakeRotation() does is fill in the matrix for a regular old CGAffineTransform. If you think you can fill (or pre-fill) the matrix faster yourself, then go for it (I'd be really surprised if this wasn't super-optimized already).
Then when it comes time to do the actual work of applying the transform, I'm pretty sure the GPU is told to take care of it so it'll run fast and your main CPU shouldn't take too much of a hit.
If you're really worried about it, then do the transforms in 2D space on top of OpenGL to make sure it's hardware optimized.
Comment: Thanks. How would I do that in 2D space with OpenGL? I have no Idea about OpenGL. Always thought that's just for 3D stuff.
Answer:
I just want to know before I start wasting my time

Optimise the system not the individual lines. Who knows how many times your code will call the transform. Better to get the whole system working, profile it and then optimise the parts that are too slow.
Don't worry about individual calls that people tell you are slow. Use this information as a pointer if your code is slow but always see how the operate in your code.


Google analytics referral path

Question: I run a website at the domain http://www.turkishbasics.com . Google Analytics is however showing the referral path of some of my traffic to be the domain itself (turkishbasics.com). How is this even possible? I've just recently moved my site from a .tk domain and this never used to happen before. I've used php 301 redirects to get traffic to the new domain.
Comment: Do you have a redirect from tukishbasics.com to www.turkishbasics.com, or can you view the same pages at the www and non-www versions of the site?
Comment: The 301 redirects are from the old .tk domain to the new .com domain. I think the site works fine with or without the www
Answer: There is a pretty amazing array of reasons why this can happen, most depend on when you consider a session has ended (some one has stopped using the site).
Most analytics programs leave a 15 to 30 minute window before recording a second non-unique visit to a site. So:-

Users leaves your site and returns seconds later (accidentally clicked an outbound link for example).
User closes one browser tab or window but has site open in another and begins to use your site again before session has expired.
User hits the back-button to Google and returns directly.
User leaves your site open in a browser window, goes away from the computer and begins using the site again after session has expired.
Internal redirects, a user clicks on an out of date link on another site and is redirected by your site to a new url - improperly configured redirects where a user passes through two stages can cause this to happen.
Not filtering YOURSELF out of your own analytics results and triggering number 4 repeatedly, or testing your own redirects over and over with your own site as the starting point.

Most common reasons are number four and number six. There are a whole host of other reasons to do with script behavior security scanning and search scanning tools it's pretty endless to be honest.
This also varies between analytics programs, Google have gotten very good at filtering some of this out but some programs simply can't because they're log analyzing or simply don't or can't track some data or user behavior.
There are a few other bugs that can cause this jensbits has a good summary the Webtrends forum has a good thread and webtrends outsider has this to say.
Answer: Google sees www.turkishbasics.com and turkishbasics.com as two different sites.
You say you have redirected your .tk to www.turkishbasics.com - but you also need to 301 redirect turkishbasics.com to www.turkishbasics.com
This is explained in google's preferred domain and 301 redirects help pages in webmaster tools.

Google analytics referral path


What do you call it when the chord progression from I to the VI but major?

Question: I think there's a similar question to this. But I couldn't pick up the exact answer that i can fully hold on to. I became more curious after listening to 'Circle of Life' where the Chord progression went from Bb-Gmajor-Cm-Gb at the climax. It gives the emotional feeling to the song for me. So i just wanted to know what's it called. Because I think the VI should be a minor if we put it in the simplest of theory. Or am I dumb? I'm sorry but appreciate the help!
Answer: It's going from parallel keys. In key B♭ major, its parallel is B♭m. But take the relative minor of B♭ - G minor, and use that one's parallel, you find G major. Hence I and VI, rather than I and vi. That VI is also the dominant of ii (Cm), and actually moves that way, so V/ii - a secondary dominant chord in a key.
Moving between parallels is fairly commonplace, going back to Classical and Baroque, and even before.
Answer: To expand on Tim's answer: As well as being a secondary dominant (especially if followed by some form of II or ii or IV), it could be the start of a "chromatic mediant" modulation (if the key of G were to be confirmed.) [That didn't read much better after translating into German.]
If the harmony continues in the original key, it's a secondary dominant.
If the harmony stays for some measures in the VI key (or a closely related key), it's the start of a modulation. The whole story may not be known until the end of the section of music containing the I-VI movement. That's one of the nice features of most musical gestures, they can have several different meanings.
Comment: Sorry - I changed the key in my answer to the one in the question, making your answer confusing! I edited yours to match.
Answer: In the case of this chord progression, the G major chord would not be called VI. Rather, it serves to lead to the ii chord — C minor. Specifically, it is the dominant, the V chord, relative to C minor: it's "V of ii", or V/ii. This is known as a secondary dominant, meaning that it's a dominant chord relative not to the main key but to a "secondary" one.


Ben Gardner's eye in Jaws

Question: In Spielberg's classic Jaws there is a scene when Hooper and Brody find Ben (they'll wish their fathers had never met their mothers), Garndner's boat floating apparently abandoned. When Hooper goes to look at the hull and finds the shark tooth, Ben's head floats down scaring Hooper into dropping the tooth, however Ben is missing an eye. I don't know how Ben dies, be it drowning or whatever, but how does he manage to lose and eye?
Comment: Not entirely sure - but there are a lot of scavenger species in the ocean. Could be a crab or something ate the eye
Comment: I know you're looking for an in-universe reason, however there likely isn't one. the screenplay specifically mentions eyes in Gardner's detached head. When it was decided to make the fake head, it may have been a decision on the day to go for even further effect or the fake eye could also have simply fallen out of the head.
Comment: @HorusKol I get your point but the incident must have happened recent to the discovery of the boat (a few hours at most) and how could a crab get onto the boat?
Comment: @CGCampbell thanks. Never read the book so not sure If character appears there. I know the actor was actually a local who Spielberg and co found funny and used him for that reason. Think 'it just looks cool' strikes again!
Answer: When the boat crashed outside of Amity, the impact of the shark hitting the boat may have caused Ben Gardner to fall over, and he could have simply had bad luck and knocked his eye out on a sharp edge or a fishhook. Or, there is always the thought of underwater creatures picking parts off of his body. Hope this helps.

Ben Gardner's eye in Jaws


Robust OCR / scanning software recommendations

Question: Ideally I would like smart batch capabilities, emphasis on image correction and tweakable OCR. An example use case: I have photos of textbook pages - the most ideal application ever would adjust for shadows and noise, apply filters to clarify text, differentiate between text and pictures and process separately, deskew and warp to compensate for curved pages, crop correctly, provide tools for OCR adjustment, and compile into a PDF. Correct me if I'm wrong, but all of these tasks are not too difficult from a developer's standpoint. If this software doesn't exist yet, whoever does it best will make millions!
Answer: Solved, with a great app called Prizmo. A few baffling interface problems (slides occasionally rearrange themselves or change their thumbnails to adjacent pages?!) but I managed to turn a set of low-light camera phone pictures of a textbook into a flat, curvature-corrected readable pdf. OCR didn't work at all but the images were so low quality that I was surprised at the few times it did; if I were more careful with the photography it could easily have read a page taken with an iPhone camera. Really great curvature correction, only a few interface adjustments would make this software perfect and efficient for a higher number of pages, like key shortcuts and some thought put into the curvature adjustment interface, or the ability to copy curvature correction settings over similar pages, or the somewhat obvious ability to pull 2 pages out of a picture/scan of a book. If they fire their current UX lead and replace him/her with a technology user the next update will be absolute gold.


What happened to AMSAT-Phase 3E?

Question: The web pages related to the unlaunched satellite were last updated in 2007, so I wonder - where is it now? Is it going to be launched someday?
Answer: P3E (Phase 3E) was conceived and partially built by AMSAT Germany in the early 2000's. In 2015, Virginia Tech thought they would be able to secure a launch and AMSAT DE was prepared to transfer the space frame to them. This launch never materialized either.
The space launch industry has changed a great deal in the last 5 to 10 years. Finding an HEO (High Earth Orbit) ride for this large of a satellite may never happen short of fully funding the launch. Such a fund raising effort has never been successfully attempted. The P3E concept was great in its time but I doubt that it will ever see space.
Comment: With an actual Phase 4 satellite payload upcoming (Es'hailsat 2), I guess they don't care about the old satellite anymore. Maybe we'll get to see it in a museum?

What happened to AMSAT-Phase 3E?


Trying to delete a program that's not open, but says it is?

Question: I've recently become nigh on obsessive with cleaning out extra space on my hard drive, and I'm trying to delete a program called "Rowmote Helper." Whenever I try to delete it, it says it can't be deleted because it is open. But when I open the "force quit applications" window, it's not running. What can I do to quit the program if it's running, or force delete it anyway? How do you force-delete an application that says that its running, but when you try to force quit it, it doesn't show up?
Answer: Go to Applications > Utilities and open up Activity Monitor. Scroll down until you find your application. Highlight it and click the "Quit Process" button in the upper left. Now it is no longer running and can be deleted from your computer.
Answer: If it's not listed in Activity Monitor, you can probably delete it using Terminal.
Open Applications -> Terminal.
First type:
<code>rm -rf
</code>
Note there must be a "space" typed after the "-rf". But don't panic if you miss it, because rm will just complain about "illegal option" and you can try again.
Then drag the file from the Finder window into Terminal, that will make Terminal insert the full path to that file for you.
Press Enter and the file should be deleted.
If it still refuses to delete (not likely), then try restarting the machine before retrying this.
Answer: On Microsoft Windows 7 just type %appdata% in the Start Menu and find the program. Delete it from there and it will be gone.
Comment: Might be difficult on OS X though...


How can I get rid of weather marks on Trex decking?

Question: We got some Trex decking in great shape, except it was originally installed upside down! So, there are marks on the 'wood grain' side where the board contacted the joists. Is there a way to get rid of those marks?
Comment: Are the marks discoloration,  or are they indentations from pressure from above. ?
Comment: What makes you think it was upside down? The original Trex didn't have an upper face, if I recall correctly. Occasionally you could detect slight cupping to the boards, but I don't believe that was an intentional design characteristic
Answer: The original Trex product fades over time and with sun exposure since it's partially composed of wood fibers. Conversely, it may darken where fungus is allowed to grow, such as where it contacts other lumber.
I'd expect the weather marks to lessen in a few months or a year. I'm not sure it's reasonable to expect to remove them, though some of the contrast may be due to soil and fungus. Try a pressure washer with some detergent and then give it some time to even out.
If that fails to provide a good outcome, a penetrating stain can be applied to create a more uniform appearance.


How can I have a paid membership sign up that includes an option for a paid premium version?

Question: Our primary membership sign up is via a dropdown list of options at different prices.  Regardless of which option is chosen, we would like to give the sign-up person an option to upgrade (via an additional check box? to a premium version at a fixed additional price.
Comment: Just to clarify, did you try using other amount and add premium option that is available if the amount is big enough - like in https://civicrm.org/sites/civicrm.org/files/after_premiums2.png (cf. https://civicrm.org/blogs/micah/contribution-pages-get-paint-job-civicrm-43) ? And if yes, what is missing ?
Comment: What do you mean by "premium option" in the context of having options in the dropdown?  What do people get from the premium option?  It would be helpful to know if the premium option is just a way to donate more (like a "contributing" member) or whether it's another set of benefits/services.
Answer: This could be done by creating a price set with the premium option, and then using the civicrm_post hook to make the change once the transaction was successfully completed in the DB.
Comment: I was hoping for something that did not require coding.  That is beyond my skill set.
Comment: Unfortunately that is likely the one that would involve the least coding. Anything else would involve coding to check a custom attribute of the membership to tell whether or not the premium option had been selected.
Answer: Pretty much the only things you can do without coding are by setting up a price set with two fields.  The first field would be the membership types in a select or radio list.  The second field would be a checkbox field with one option.  It could be a regular field without any membership tied to it, and you'd just be collecting extra money if someone selects it.
If you wanted to track an extra set of benefits, you might create another membership type with a different membership organization and tie the checkbox to that.  The membership organization indicates that it's not an alternative to the main membership but rather a membership that you can hold simultaneously with the other one.  It'll make your life more complex in some ways, but you'll be able to quickly see who's got the premium membership.
Comment: I had success with Andrew's response.   Also found this documentation which was very helpful working it out.   No coding was required!
http://book.civicrm.org/user/current/membership/membership-pricesets/
Answer: Although I don't think this will satisfy Dave T's need for something without any coding, the following would be my preferred way.
Let's say you have three membership types, each with premium/non-premium options:

Student member
Individual member
Family member

You'd create six membership types in CiviCRM:

Standard Student member
Standard Individual member
Standard Family member
Premium Student member
Premium Individual member
Premium Family member

Then, set up a price set with two fields.  One is radio buttons with one option per membership type.  The other is just a single checkbox with no price (but a label saying "go premium for $100" or whatever).  You add a bit of javascript to the form that does the following on page load and every time the checkbox changes status:

if the checkbox is checked, show the premium options, see if one of the non-premium options is selected, select the corresponding premium option, and hide the non-premium options, or
if the checkbox is not checked, show the non-premium options, see if one of the premium options is selected, select the corresponding non-premium option, and hide the premium options.

The result will be a single membership type, so it's easy to maintain, report, etc.  However, from the member's perspective, the experience is one of an add-on rather than navigating among a bunch of options.


Can player characters pick monster feats?

Question: Some of my player characters have a race from a template but without monster hit dice (like half-orc) and others have a race from a template with monster hit dice (like ogre). Now in the back of Monster Manual I there are some monster feats, like Awesome Blow. It says these are available to monsters so I guess the half-orc character cannot select these, but what about the ogre character? It does have monster hit dice after all.
Answer: The Monster Manual feats aren't limited to monsters
A feat can be taken by any creature that qualifies for the feat based on the feat's type (for example, the most common type of feat is general, but the Player's Handbook also includes the feat types item creation and metamagic) and that meets the feat's prerequisites and that fulfills any conditions explained in the feat's description, benefit, special, or note (if any).
So, while the Monster Manual feats are "typically used only by monsters" (MM 303), if a PC meets the requirements for taking such feats, nothing technically prevents the PC from taking feats from the Monster Manual.
The DM can always say No
If the DM—for whatever reason—doesn't want a feat in the campaign, the DM can make a house rule saying that feat is excluded from the campaign. As an aside, while it's usually easier to say, "No feats from this book," it's often better to ask a player's plan for his character instead then assess feat choices individually. Usually, a particular book has a mix of strong and weak feats, and banning a book means eliminating both reasonable and unreasonable choices.
Comment: @Carcer Can you cite a source for that? While that's a deeply reasonable house rule (and I don't use the term disparagingly), I am pretty sure a creature *must* meet a feat's prerequisites upon being *able* to take a feat *to* take a feat. That is, even if a creature *can* gain temporary abilities that enable the creature to meet a feat's prerequisites, if the creature doesn't meet the prerequisites when the feat would've been taken, the creature can't take it.
Comment: Exactly this, keep in mind that feats such as "Awesome Blow" are incredibly easy for a DM to counter because of their high requirements.
Comment: Yes, most "monster" feats have prerequisites that a normal player character would not be able to meet. It's worth remembering however that a character who doesn't innately have a particular ability but can reliably attain it can take a feat which depends on that ability. For instance, a Druid who can use Wild Shape to become a creature with claw attacks could take Improved Natural Weapon (Claw), it just only applies when they are in the appropriate form. Or a fighter with Wings of Flying could take Flyby Attack. If you can do it reliably enough to practice it, you can take the feats.
Comment: @HeyICanChan I wish I could but I've tried to search it now and realising I might have been conflating different things. [This question](http://rpg.stackexchange.com/questions/60089/can-a-character-meet-prerequisites-using-a-magic-item) has some relevance. However I think I was specifically thinking about Pathfinder, where the Fly skill states: "You cannot take this skill without a natural means of flight or gliding. Creatures can also take ranks in Fly if they possess a reliable means of flying every day (either through a spell or other magical manner, such as a druid's wild shape ability)."
Comment: @Carcer It's cool. An example of how complicated it can be to take feats for which the creature only *temporarily* meets the prerequisites is detailed in my answer [here](http://rpg.stackexchange.com/a/63292/8610) if you're interested.


How to test whether UI is usable with touch-screen on desktop

Question: We are developing application for mobile platforms. But it can be tested on (windows) desktop and it's obviously easier than uploading to device. However mouse is quite a bit more precise than the touch screen, so testing on desktop will indicate different things as easy/hard to use than testing on device. Is there any tool or methodology for approximating control with touch screen (and rather thick finger) on desktop?
Comment: The application shouldn't be too difficult to upload to an actual device. You should try it in a real device, a few different ones, if possible.
Comment: @PatomaS: We are testing it on devices. Dozens of them. Regularly. It's not too complicated to do. But it will always be more complicated than on desktop and the difference means that the developer working on the user interface will never do it after each change.
Comment: Hi Jan; are you waiting on anything else before marking an answer as accepted?
Answer: There's no substitute for using a touch-screen for testing. If you're developing on Windows you can buy an infrared touch frame extremely cheaply (generally under $50), which is basically a frame of IR LEDs and IR sensors around a clear plastic or glass window, and a USB cable to connect it to your computer. This then sits in front of your existing display and is natively supported by Windows as a touch screen. Super, super easy.
Alternatively you can buy an external touch display (which can support anything up to 20 finger multitouch).
If you can't afford (or get your hands on) a real touch display, there are some little things you can do:

Follow the platform's touch guidelines. Where to look for these will differ depending on the platform you're building against.
Use an app like PhoneFinger (sadly seems to be discontinued but you can still find it around the place), which changes your mouse cursor to a big, obnoxious hand (and thus allows you to see how well your UI allows you to tap what you're trying to tap).
If you're building an app for iOS, you could try an app like LiveView to allow you to view your PC screen via the device itself (without needing to deploy your app over and over again).
Comment: That's what I was looking for. Unfortunately that application (otherwise an easy option) is for MacOS only; we are developing for multiple platforms and only 2 of us who do the iPhone port have MacOS (and nobody else really wants it; the development environment there can't be exactly called stable and reliable)
Comment: @JanHudec: if they're Windows users, they can use a (paid) app called [CursorFX](http://www.stardock.com/products/cursorfx/) to set any image as their mouse cursor (including, but not limited to, a giant transparent PNG of a hand; perhaps even sucked straight out of PhoneFinger for consistency). It's a bit more manual than the Mac solution (and being primarily a Mac user I can't vouch for its ease-of-use), but that should allow them to perform the same effect.
Comment: Also you can use a webcam to record the user's experience and see where they get confused or hesitant. You can use an affordable sled from somewhere like here: http://www.ponoko.com/design-your-own/products/iphone-usablilty-testing-sleds-6854
Answer: First of all why would you build an application for a mobile platform and not test it on the platform itself? Personally I would prefer real life user testing on several mobile devices.
But if you have no option to do this you could try something like the touch template developed by Steven Hoober. I haven't used it personally but it seems like an easy and straightforward solution to finding some of the problems you mention.
Image of the touch template:
http://www.touchusability.com/storage/example-interference.jpeg?__SQUARESPACE_CACHEVERSION=1345404148235
Site of Steven with an explanation:
http://4ourth.com/wiki/4ourth%20Mobile%20Touch%20Template (site currently not working, hopefully later on)
-Tom
Comment: We definitely test on the target platforms. But when refining the design, we need to test it, do quick tweaks to the layout, test again, do more tweaks and so on. Uploading to most devices is not exactly straightforward, so I was looking for most efficient simple test.
Answer: Perhaps you could somehow emulate a mobile device with a small touch screen monitor attached to the desktop itself?


How do I estimate convergence in monte carlo methods?

Question: I am experimenting with Monte Carlo methods. I'd like to measure/estimate convergence with a graph/chart.
How do I do that? Can anyone please direct me to relevant documentation/links or even give me tips or general guidelines?
Thanks in advance,
Julien.
Comment: Convergence of what? Can you please be more specific. Also what applications/tools do you use to experiment with Monte Carlo?
Comment: Hello. I mean convergence of my results. I use Java in order to evaluate a European Option. So the results are the option prices. I have suceeded in calculating the sample variance running 20 runs. I am not sure if there is a better alternative than the sample variance. Julien.
Comment: Agree with Val. What type of option? Why monte carlo for a european  when there's a closed-form solution (BSM)? If you are questioning what your chart should look like, typically you have price on the Y-axis and run count on the X-axis.
Answer: You are typically interested in evaluating $E\left[ f(X_T)-f(\bar{X}_T^{(n)}) \right]$ (refered as the weak convergence)

$X_t$ the solution of the sde : $dX_t^x=b(X_t^x)dt+\sigma(X_t^x)dW_t$
$\bar{X}_t^{(n)}=b(\underline{t},X_{\underline{t}}^{(n)})\cdot (t-\underline{t})+\sigma(\underline{t},X_{\underline{t}}^{(n)})\cdot (W_{\underline{t}}-W_t)$  is your Euler-continous discritized SDE, with $T/n$ your time step.

under some regularity assumptions on both your SDE coefficients and payoff function $f$ ,

The rate of convergence is $o\left(\frac{1}{n}\right)$
Expansion of order $\frac{1}{n}$:
  $E\left[ f(X_T)-f(\bar{X}_T^{(n)}) \right]= \sum_{i=1}^R\frac{c_k}{n^k}+O(\frac{1}{n^{R+1}})$

A strong  condition would be $b,\sigma,f$ are $C^\infty$ with $f$ having polynomial growth (i.e. $\exists r>0,  |f(x)|\leq C\dot(1+|x|^r)$).
Basically, if you don't know the true value of your Eu. option you would approximate it with $E\left[ f(\bar{X}_T^{n\approx\infty})\right]$ , and then trace $n\rightarrow E\left[ f(\bar{X}_T^{n\approx\infty})-f(\bar{X}_T^{(n)}) \right]$ and observe a $o(1/n)$ behavior (and try to guess the value of $c_1$).
Note also that using the second assertion you might avoid using an estimate of your option. Indeed, consider $\bar{X}_T^{(n)}$ and  $\bar{X}_T^{(2n)}$ two Euler schemes with different time steps (the second has one time more steps). Then, by applying the error expansions to the first scheme,
$E\left[ f(X_T)-f(\bar{X}_T^{(n)}) \right]= \frac{c_1}{n}+O(\frac{1}{n^{2}})$
and then to the second scheme
$E\left[ f(X_T)-f(\bar{X}_T^{(2n)}) \right] = \frac{c_1}{2n}+O(\frac{1}{n^{2}})$
we get,
$ E\left[f(\bar{X}_T^{(2n)}) - f(\bar{X}_T^{(n)}) \right] = \frac{c_1}{2n}+O(\frac{1}{n^{2}})$
Finally, without knowing the exact value of your european option ($E(f(X_T))$) you can get the exact (first order) rate of convergence, $n\rightarrow E\left[f(\bar{X}_T^{(2n)}) - f(\bar{X}_T^{(n)}) \right]= c_1/n$. Needless to say, that $c_1=n\cdot E\left[f(\bar{X}_T^{(2n)}) - f(\bar{X}_T^{(n)}) \right]$.
(This useful expansion also known as the Romberg expansion is also used to build accelerated  Monte-Carlo estimates, with the same notations we obtain  $E(f(X_T)-2E(X_T^{2n})+E(X_T^{n})=\frac{c_2}{n^2}$)
A (dated) reference would be  Bally and Talay
Answer: Julien, frankly I have no idea what your research question is...
Since you are quite vague in formulation your question I can only provide a vague answser...
The following academic papers might be of use
http://www.jstor.org/stable/1428344
http://www.math.ethz.ch/~mschweiz/Files/converge.pdf
and I suggest you take a look at:

Introducing Monte Carlo Methods with R     by  Christian P. Robert · George Casella

it will give you concrete examples of applying monte carlo methodologies


Is it possible for malware to be in the BIOS or in hardware?

Question: Is it possible for malware to be written in the BIOS section and loaded on every fresh Windows Install? If it is possible, can this affect Linux (Ubuntu and others) operating systems as well?
Comment: The first article turned up by a google search of "BIOS viruses" includes this quote: "Further investigation soon showed that the list of affected operating systems also included multiple variants of Windows and Linux."
Comment: Have you tried looking this up? lmgtfy.com/?q=BIOS+viruses
Comment: I'm looked up but im interesting does it affect Linux OS
Comment: Yeah, it can affect Linux. Linux and Windows are both operating systems. One of the main jobs of the BIOS is to get the computer to a place where it can load the operating system (Linux, Windows, etc). So, the BIOS is running before any operating system and so a BIOS virus can in principle be independent of an operating system.
Answer: Yes, the BIOS is software. If it is writeable/flashable, it is possible for the BIOS to be overwritten or modified such that it performs malicious actions. The BIOS boots before the operating system and bootloader, so it is entirely possible for BIOS malware to impact and infect on each boot or on fresh installs.
This is not a windows specific problem. The BIOS provides the lowest level hardware interaction/abstraction and the OS will depend upon this code, so it may be possible to write generic or OS specific malware.
You may be interested in this paper and this presentation.
The MITRE Copernicus tool can be used to do checks for malware in BIOS.
Answer: Yes it is possible although newer bios has code signature protection which make this attack unprobable. The BIOS is tied to the computer architecture in this case x86/x64 and it's end goal is to load the OS. So no matter the OS even no OS you can flash (write) the BIOS.
However, the BIOS is not a malware delivery channel. For any useful work (accessing virtual memory, the file system, the network etc..) you'll need to run the malware code after the boot loader. The first stage boot loader has the same limitation and has only 640kb of space so you couldn't put much malware there. The second stage boot loader would be the first location where you could execute useful malware code after the filesystem has been setup. It is more practical to develop a device driver to deliver low level malware and leave the boot process untouched.