Proper way to address a bhikkhu?

Question: I have seen many ways to address a bhikkhu, and I'm wondering about the proper way to address a bhikkhu, in writing?
Answer: Bhante is the preferred mode of address if you are addressing the bhikkhu respectfully; note that it is masculine, so for bhikkhunis, Ayye is correct (mostly they use ayya, but I don't think that is technically correct). In English, Venerable x and Reverend x would also be suitable expressions of respect.
If you are addressing them as an equal or as an outsider to the religion, Venerable x and Reverend x would still be proper, I think, but even Brother x would be okay. In Pali, words like bho and ayasma were also used, meaning something like "good sir" or "friend" by those who didn't hold the bhikkhus in any special esteem.
In writing, using the nominative endings (e.g. o for -a stem names) is not technically correct when addressing the bhikkhu in the second person, e.g.:

Dear Venerable Yuttadhammo,

should really be:

Dear Venerable Yuttadhamma,

In Thailand this distinction has been pretty much lost, whereas in Burma and Sri Lanka they prefer the a endings for all references.
In Pali, when referring to someone in the third person, you would use the nominative endings, but in the case of corresponding in English, the dictionary stem form is certainly acceptable, as it is with 'buddha', nibbana', etc. Just as we don't say:

The Buddho was staying in Savatthi.

we really shouldn't be saying:

Venerable Yuttadhammo was staying in Florida.

As for regional honorifics, e.g. Ajaan (Ajarn, Ajahn) in Thai, Ashin in Burmese, Hamuduruvo in Sinhala, Lakhun in Khmer, etc., I would suggest they only be used by members of the specific ethnic community; I wouldn't think them appropriate for non-members to use to refer to members (e.g. Westerners calling Thai monks Ajaan) unless speaking in the language from which the word comes. In practical usage, however, Ajaan for example has become so widely used by Thai people (even for monks who clearly aren't their or anyone's teacher) that they often insist that non-Thais use it to refer to Thai monks, which of course would be the wise choice when among such people.
Comment: added some thoughts on regional honorifics
Comment: Thank you, Bhante. Could you please include the use of Ajahn (teacher?) in your tradition, in the answer? Or is that a separate question?
Comment: Ajaan is only proper if you are Thai, just as Ashin if you are Burmese. I don't know why all the Western Thai monks still use it as a part of their name; meaning teacher, it's not something one should expect ordinary people to use.
Answer: Ven. Yuttadhamma wrote:
"Bhante is the preferred mode of address if you are addressing the bhikkhu respectfully; note that it is masculine, so for bhikkhunis, Ayye is correct (mostly they use ayya, but I don't think that is technically correct)."
To comment briefly on this - i have learned of "Bhante" as the vocative contraction of "Bhadanta"--an "expositor" [of the Dhamma], used for "master" teachers. Buddhist historians say that early on, in the Buddhist monastic Sangha, only the Buddha was addressed as "Bhante".  Later, after the Buddha's parinibbana, other monastic teachers came to be addressed as "Bhante" as well. But were they all men?
Epigraphically, in donative inscriptions from the Indian subcontinent, we find at least one reference to a bhikkhuni teacher with the title "Bhadanta".  In the vocative, she should be addressed as "Bhadante", or by the contraction "Bhante".  There are comparatively numerous donative inscriptions in which we find the honorific "Ayya" prefixing bhikkhus' names; in hypothetical example: "Ayya Yuttadhamma Bhikkhu".  This could be translated as: "the noble bhikkhu Yuttadhamma".
When and how it happened that "Bhante" came to be used only for men and "Ayye" only for women, or at least generally so, as we find much of the time in the Pali texts is not known to me.  We do several times find bhikkhus addressed as "Ayya" in the Pali-text canon. In example, in the bhikkhuni ordination proceedings from the Pali-text Vinaya, the new bhikkhuni when coming to the Bhikkhuni Sangha to request the confirmation and completion of her full ordination as a bhikkhuni is to address the Bhikkhu Sangha as "Ayya" (here in the masculine plural vocative).
Comment: It would be good if sister would modify the approach so that it does not appear respectless.
Answer: If its Theravada you can never go wrong either just the name " yuttadhammo bhikku" or Bhante. In Thai you can say Ajahn,  a word basically similar to bhante.
I personally just use Bhante(means teacher) ,  its quick,  easy,  and used from ancient times. In fact i am in email communication with a bhikkhu at the place im going to hopefully ordain,  and i start emails with Bhante.
Bhante (Pali; Nepali; Burmese: [pronounce-ဘန္ေတ] [write-ဘေႏၲ] Burmese font used - Zawgyi-one font, pronounced: [bàɴtè], Sanskrit: vande and vandanā ) is the polite particle used to refer to Buddhist monks in the Theravada tradition. Bhante literally means "Venerable Sir."
Comment: And bhante comes from skt. bhavantaḥ, not vande... just FYI. Ajaan comes from acariya, meaning teacher.
Comment: Apologies bhante i took the definition from the net,  ill check my sources next time thanks for correcting my comment.
Comment: Calling someone Bhikkhu is not really appropriate; kind of like saying, 'hey, monk'.
Answer: I would say address them in the most respectful way in your culture and native language.   "Sir" might be sufficient in English.  To me, it is an attachment to rites and rituals (3rd fetter) if you use the most appropriate words expected by community but not sure why or even using them without true respect.  But again, you want to have organization and harmony in the community, so once you find out what words are used, then use it with respect.
Comment: thank you for kind comment. my understanding of 3rd fetters also covers doing right thing but without understanding why.  The key is "not understanding reason behind it.  For example, you may have seen people of some faith that requires believers to cover their hair to be modest, but now a day you see a few of them with hair covered but very tight revealing outfits.  that defeats the purpose of covering thier hair to be modest in appearance.  Those hang on tightly to the belief of hair covering but forget the purpose behind it.
Comment: similarly to original question,  FullPeace.org has found the right words but my addition to that was to make sure to understand reasons for using those words.  What good if the correct words are used but without truly feeling respectful.  To rephrase my answer, it doesn't really matter what words used as long as it is said from respect, but to promote harmony, use same words as the community also with respect.
Comment: this is exactly my point "attachment to rituals" , conversation will never end trying to come up with proper way to address or "greeting ritual" if you may.  But as long as you you have respect.  I would imagine if a bhikku is in town where high five is a form of most respectful greeting and not against Vinaya.  Just as ancient Indian walking around someone or something 3 rounds was one of the most display of respect one can do to a person or a place, but now, many buddhists dont understand that "ritural".
Comment: Let us [continue this discussion in chat](http://chat.stackexchange.com/rooms/58015/discussion-between-dean-a-and-samana-johann).
Comment: Its not an attachement to rites and rituals, or would Dean say Arahats are still attached? The third fetter means "being attached to rites and ritual not contuctive on the path." (Often wrong interprated) Paying proper respect is a matter of Sila and throw down even all aggregates by mind, speech and body in front of Buddha, Dhamma, Sangha it can couse even path and fruit. Aside of that, good and respectable and practical answer @Dean A.
Comment: That is right, Dean. Nevertheless, would you tell people not even capable to follow simply rituals of the wise, to start with abhidhamma and understand there mind? Actually such is mostly a smart excuse of defilements, or? So if having a good appearance in general, why not also cover the hair? Modest in regard of being perfect or I am ugly, why should I wear something to cover my hair? As for the beauty without cover and the ugly waering, of whom a wise would say that he tries the best of his possibilities and a person of respect and virtue? The answer was on the first replay.
Comment: There is no need to respect a certain community with maybe even improper and unskilful ways of adressing and how to pay respect. If a certain community is not up to respect and venerate of what is worthy of that, than, its good and proper to leave it and not to take on usuals. That is totally wrong. So if messured, and addopted its good not only to follow one feeling but also ask the wise and Elder of what is proper. Give me five and lifting the hand when for example a Bhikkhu crosses certain townships? If you tell them, just follow you community than you have what we already have, Dean. Like?
Comment: Atma (my person, usual kind form of adressing one self, speaking with householders and not ordained) needs to take 2, 3 h sleep since nearly 2:00 and will stop here. Since the community or leaders will surpress discussions, Upasaka (?)  Dean is welcome to talk about it on sangham.net . Just from experiances, 95% of so called Buddhist explode within minutes talking straight on this topic, since the modern world and specially those on internet, are really fare from even small amounts of proper paying respect. Again, such is not really in the sphere of Dana and generosity, deal, but a matter of v
Comment: Worthy a read: [Opening the Door to the Dhamma: Respect in Buddhist Thought & Practice](http://zugangzureinsicht.org/html/lib/authors/thanissaro/respect5_en.html)
Answer: Things to consider in regard of the OP's Question, since a proper Question would be: "How do I address monastics, Brahmans and ascetics in a way that it is of most benefit for me?"
To understand the merit an demerit of paying respect a little, my person wrote a "wiki-like" articel, supported by members here:  Respect and Veneration
In bodily regard:
Is you aspect being taught well by a Monk, you should consider that especial a Bhikkhu is not allowed to teach to someone:

holding an umbrella (unless he is ill).
holding a stick (unless he is ill).
holding a cutting object (unless he is ill).
holding a weapon (unless he is ill).

(for internet this means to people holding power while one would speak - moderators and others with tendency to delete or banning, willing to put Dhamma in that wsy under their power)

who is wearing shoes (unless he is ill).
who is wearing sandals (unless he is ill).

(appearings of not respecting the place of Dhamma talks and putting them selfs higher)

who is inside a vehicle (unless he is ill).

(One in hurry, just passing by)

who is lying down (unless he is ill).
who is sitting with the knees raised and the arms around (unless he is ill).
wearing a turban (unless he is ill).
whose head {and sholders} is covered (unless he is ill).

(One with an improper Avatar, not showing his face.)

sits on a seat while the teaching is sitting directly on the ground (unless he is ill).
sitting at a higher level and the teaching on a lower (unless he is ill).
who is sitting while one is standing (unless he is ill).
is walking ahead (unless he is ill).
who walks on a footpath while one is walking to the side of this footpath (unless he is ill).

(If situations and views are hold, monks are equal to others here)
All this things are not conductive in regard of peoples respect in reagard of the Dhamma. For Monks themselves also a personal protection.
In regard of demand and compensation:
Monks, keeping Vinaya, do not and never teach for rewards or let the taught be bound by any contacts or demands. Accepting gifts, rewards or other things as reward for teaching is not the way of the Noble Ones and there are rules to cut off possible corruption of the Dhamma in that way. So gifts as well as the gift of veneration is good placed in advanced to gain most benefit and make it acceptable.
Speech:
What ever feel proper to one, thinking on someone who is not only high above one self but also could give one the highest gift possible to give.
Usual ways are to express his worthy be calling him Ven. Sir, Lord, Lord of Compassion, Ven. Teacher and if in Pali, as usual, "Bante". For female likewise.
In third person, whether he is at place or not, its also good to do such in that way. If there are more Monks, put the name behind. Its not usual and polite to use the "Status/Profession" like Bhikkhu, Samanera, monk, Samana.
Consider always, that a ordained person has actualky no gains be receiving respect, and if he/she takes such not worthy of it, he/she just accumulte depts. Giving or not giving in this regard is the doers benefit or demerit, whether he/she knows or not. Not knowing does not eliminate causes.
Its also good to have mistrust is monks and laypeople associate like friends and address each other very familar.
Generally again, this topic is very large and it is good if one maybe takes the linked article and asks further questions in detail.
Modern people today must be aware that they are usuall taught and trained in a post-modern or "communistic" way, wrong view, empathizing all are equal.
In such an enviroment, under such believes, its never possible to gain anything, how much Dhamma ever one would read, be taught... gains in ways not in line of Dhamma.
Keeping precepts and being tended to virtue (of what veneration of what is worthy of verneration is on part) and to take Buddha, Dhamma and Sangha really as refuge, venerate by heart, are the signs of a faith follower, and stream-enter, both no more able to fall off the path of liberation.
If you are a person with long meditation practice or of much knowledge in Dhamma, if you are a virtuose person for your self and consider your self as experianced and still have problems and aversions in regard of Veneration, it is a good sign that such a practice was not based on Right View and the refuge is not really taken.
Its a really good working place to get ride of very raw defilements and at the same time also possible to drop down all clinging aggregats just by a poor cousin treaded single deed.
Asking Questions:
While it is not wrong for a Monk to teach even not invited, one does good when raising a question, to address an venerate possible present persons proper. That is also generally. While usuall everywhere is very rude and a sign of low education and virtue, to put just ones question into the "marked" without kind greatings. Even if a person of good contact enters a shop, here a costumer, he would great friendly and show signs of politeness.
So generally people incl. the moderators have a lot of work if wishing to be frequented by Monks aside of just short visits and those with certain improper aims, using such places like most here, for certain other gains outside good or no trade.
Those follow the tradition of the Noble Ones will never addopt certain social and timely usuals but hold on that others, being willing, are able to addopt those, step by step, leaving both improper ways of live in the world or even the eorld behind.
Like every teaching, this words are originated by compassion, and not made to demand anything. What ever one gives is the givers reward. So is it with taking.
Addition in regard of "warm" addressings :
In SEAsia is very common to use Ven. father, grandfather, oncle, great brother... Such is usual under uneducated people and not really proper, althought both might like it. One would address a lay priest of a village or his honored father or granduncle like wise. Such as brother or sister are merely usuals comming from commonist countries and, in setting even equal, totally improper. Its good to use respectful "cool", with proper distance, addresses. Such is very common in "Guru" paisas and put single individuals high and warm. While of course no problem for uninstructed people with raga- or saddha-charita, a good instructed person does not use such warm addressings.
(Note: This is a gift of Dhamma and not meant for any commercial purpose or other wordly gains.)
Comment: How ever Upasaka Chris (better "Nyom" (Chris)) , feels as proper and likes to give. Usually people adress my persons appearing with Bhante in the west (which fits to normal usuals), usual adressings here (Cambodia) are from Ven. older brother to Ven. Grandfather, Lord of compassion, Ven. Sir., Ven. Master, ... if translated. "Warm" adressing used most by villagers and people not so educated, Ven. Grandfather and the others by knowledgeable housholders, Samaneras and Bhikkhus. Personally, Atma really does not care, althought such always gives certain reason for either mudita or karuna.
Comment: May I ask, what is the proper way for me to address you on this site? When you post a comment to me, you tend to include "ChrisW" and sometimes "Upasaka" in your comment. Would you like me to do the same when I address you? For example when I begin a comment, should I start by writing "Samana", or, "Samana Johann"?
Answer: Whatever identifies that specific monk. That's the purpose of a name. I tend to use only their monastic name or, if they teach, I use 'teacher' in their local idiom. Keep things simple & respectable.
As for a "proper way", there are as many answers as there are people, I guess.
Comment: Paying respect in regard of what is worthy of respect is not a matter of what is easy, Unrul, but a merit. Merit has always to do with giving up and letting go of one self. Paying reference is also grouped under Sila and not only out of that countless more benefical as practicing generosity, even a life time. So its really not about identify and also ask for what is proper and not how Hinz and Kunz does it. Maybe consider that in your answer, since also such if of good or bad results.

Proper way to address a bhikkhu?


Orthonormal Matrices-Intuition

Question: Why is it, geometrically, that the row space is ALSO orthonormal? What exactly does the transpose LOOK like? Normally the row and column space are two separate things, but in the case of an orthonormal matrix, you have that the row space is actually the inverse of the column space, so also, what does an inverse space look like? I feel there should be a very good geometric interpretation, but I don't see it.
Answer: I think this is actually a good question. We can talk about two things: the geometric intuition of an orthogonal matrix and the relationship between row and column space. The latter is slightly more general.
In the first place, let $O(n) = \{A \in M_n(\Bbb E) : A^T A = 1\}$, and let $SO(n)$ be the restriction of $O(n)$ to matrices with determinant 1. Note that this basically gets rid of the $A$ with negative determinant, since the condition $A^TA = I$ implies
\begin{gather*}
1 = \det(I_n) = \det(A^T A) = \det(A^T)\det(A) = \det(A)^2,
\end{gather*}
since the transpose does not affect the determinant (prove it or trust me, it's probably not the key idea on a first reading, though it is a consequence of and implies non-trivial things). Therefore $\det(A) = \pm 1$.
Always give yourself simple examples (and counter-examples!). For instance, take
$$A = \begin{pmatrix} 1 & 0 \\ 0 & -1\end{pmatrix}.$$
This matrix is not in $SO(n)$, since $\det(A) \neq 1$. Geometrically, this matrix is a reflection across the $x$-axis. To see this, see what happens to the basis vectors $(1,0)$ and $(0,1)$. The $x$-coordinate (1,0) stays fixed, while $y \rightarrow -y$. Note that this does not preserve orientation. That is,

Flips aren't all bad though. They still preserve volume. Matrices in $SO(n)$, however, preserve both orientation and volume and can be viewed as rotations. Consider for instance the matrix
$$R = \begin{pmatrix} \cos\theta & -\sin\theta \\ \sin\theta & \cos\theta \end{pmatrix}$$
This is a rotation matrix in $\mathbb{R}^2$. Its characteristic polynomial is $\lambda^2 -2\lambda \cos\theta + 1$, and the discriminant of this polynomial is $b^2 - 4ac = -4\sin^2(\theta).$ Therefore, whenever $\theta \neq 0 \pmod{2\pi}$, the eigenvalues are imaginary. The eigenvalues of an orthogonal matrix always have norm $1$, so they are of the form $e^{i\theta_k}$ for various $k$.
If you want to talk about row and column space, you're going to have to think about the adjoint map a bit, i.e. $A \rightarrow A^*$, where $A^*$ is the matrix which satisfies $(Au,v) = (u,A^*v)$ for every $u, v$ in the vector space. Here $( \cdot,\cdot)$ denotes the inner product on the space (say the Euclidean inner product $x \cdot y$).
It turns out (one can prove by straight linear algebra by expanding sums and re-arranging terms) that the matrix which satisfies precisely that condition is always the transpose of the matrix. One can then ask what the relationship between these matrices is, or how one can think of them.
One interpretation is that if $A$ is a map from the vector space $V$ to v.s. $W$, then $A^* : W^* \rightarrow V^*$. Here, $V^*$ denotes the dual space of $V$ (ditto $W$). It can be seen as the map on row vectors ('dual vectors') induced by the map on column vectors.
Note: the reason I call row vectors 'dual vectors' is because one can associate to any row a linear functional on the vector space: write the row as $v^T$ and act on vectors $u$ by $u \rightarrow v^Tu \in \mathbb{R}$.
If you want I can get into this, depends on how much of this is below/above your level.
Answer: I think your question is non-trivial.  One way to see this is to consider the same problem in infinite dimensions.  Let $H$ be an infinite dimensional Hilbert space with o.n. basis $e_1,e_2,\dots$.  Let $T$ be the operator
$$ T e_i = e_{i+1} .$$
Then in some sense you can say that the columns of the matrix representing $T$ are orthonormal.  In other words, $T$ is an isometry.
But now consider the adjoint operator $T^*$.  This corresponds to the transpose of $T$.  But $T^*$ has a one-dimensional kernel, and hence it is not an isometry, and hence its columns are not orthonormal.
This means that any answer to your question must take into account the fact that the matrix is finite dimensional.
Answer: I'm unsure of exactly what you expect for "looks" like, but $O$ is orthonormal precisely when $O^T O = O O^T = I$.  It works in both orders of the multiplication because that's how inverses always work: if they invert on one side, they invert on the other as well.  $O^T O = I$ is precisely the statement that the columns are orthonormal, and $O O^T  = I$ is precisely the statement that the rows are orthonormal.
Answer:
Why is it, geometrically, that the row space is ALSO orthonormal? What exactly does the transpose LOOK like? [...] I feel there should be a very good geometric interpretation, but I don't see it.

Just synthesizing the existing answers and making some tacit points explicit.
For definiteness, let $A$ be an $n \times n$ real matrix whose $i$th column is $A_i$, viewed as an element of $\mathbf{R}^{n} = \mathbf{R}^{n \times 1}$, and let $A^t$ denote the transpose of $A$, i.e., the $n \times n$ real matrix whose $i$th row is $A_i^t$, viewed as an element of the dual space $(\mathbf{R}^{n})^* = \mathbf{R}^{1 \times n}$.
As zibadawa timmy notes, the columns of $A$ are an orthonormal set in $\mathbf{R}^n$ (i.e., the matrix $A$ is "orthonormal" in the OP's terminology) if and only if $A^t A = I$. Since $A$ is a (finite-size) square matrix of full rank, $AA^t = I$ as well, which implies the columns of $A^t$ are an orthonormal set in $\mathbf{R}^n$. (It's not clear the OP would view this argument as "geometric", but these observations directly answer the OP's question as I understand it.)
Finite-dimensionality is crucial, as Stephen Montgomery-Smith notes; the right shift operator in (e.g.) the space $\mathbf{R}^\infty = \bigcup_n \mathbf{R}^n$ of all finite (i.e., eventually zero) real sequences may be represented by a matrix $A$ with orthonormal columns, but having the zero vector as first row.
Finally, as snarski notes, the column space of $A$ is, properly speaking, a subspace of $\mathbf{R}^n$, while the row space of $A$ lies in $(\mathbf{R}^n)^*$. However, there's a tacit choice of inner product on $\mathbf{R}^n$ in the original question (the columns of $A$ are "orthonormal"), and this defines a "natural" isomorphism from $\mathbf{R}^n$ to $(\mathbf{R}^n)^*$, namely the transpose operator exchanging column and row matrices. Under this identification, the adjoint map $A^*:(\mathbf{R}^n)^* \to (\mathbf{R}^n)^*$, represented by the transpose $A^t$, is itself orthogonal (inner product preserving), so its matrix also has orthonormal columns. This is tantamount to saying $A$ has orthonormal rows.
Answer: A real orthogonal matrix is geometrically a rotation, a reflection or a permutation of the axes.  For example, the matrix M =
$\begin{pmatrix}
cos(t) & -sin(t)\\
sin(t) & cos(t)\\
\end{pmatrix}$ rotates any vector through an angle of t.  $M^{-1}$ undoes what M did, which is to say, it rotates every vector back through the angle (-t) and leaves it where it started.  The matrix
$\begin{pmatrix}
1 & 0\\
0& -1\\
\end{pmatrix}$
reflects a vector across the x axis and its inverse reflects it back. This matrix can also be expressed in terms of sines and cosines if you wish.
The matrix
$\begin{pmatrix}
0 & 1\\
1& 0\\
\end{pmatrix}$ maps the x-axis into the y-axis and the y-axis into the x-axis.  It inverse does the opposite.  It also can be expressed in terms of sines and cosines.
To be sure this is right, just compute what each matrix does to a sample of vectors; figure out what its inverse is, and see that it undoes what M did to your sample.

Orthonormal Matrices-Intuition


Why does a 97 / 92 key piano exist by Bösendorfer?

Question: Pianos normally have 88 keys, ranging from A0 to C8.  One of Bösendorfer's pianos go down to F below the low A.  The other model goes down to C.  How did this happen?
Comment: Personally, I'd ask the opposite question - why did everybody else stop at 88?  I mean, I very rarely see any music which uses the top or bottom octave on a standard 88, but that's no reason to not give people the option.  Also, if you're looking at any music, say, before mid-Beethoven, they only had a 5-octave range anyhow, so composers faced the same limitations as players.  Who knows what they would've written had they the range to do so?  You can even see in some early Beethoven where he was struggling to fit certain motifs within the range of the smaller pianos that existed at the time.
Comment: @DarrelHoffman - I've seen the bottom octave of the piano used often enough in classical music. In several of those cases, I've even seen those notes notated with ledger lines but no ottava lines.
Comment: I'd suggest they stopped at 88 for a couple of possible reasons.  A0 = 27HZ in equal temperament with a baseline of 440 on A4.  At a lower pitch range, say, A4=432, if my calculation is correct, A0 is 22.375 HZ.  The average range of human hearing is about 20 HZ to 20KHZ ... so A0 is about as low as the human ear could differentiate pitch on the piano in the 1700-1800's.  There was just not much point in try to go any lower at the time.  The historical gradual upwards shift of the reference tonal center and Bösendorfer's competitive spirit might explain why they make a 92/97 key model.
Comment: For example, Tchaikovsky's Piano Concerto No. 1 requires both A0 **AND** C8 to be played on the piano!
Comment: Hi I've just composed something that use 88 / 92 / 97 / 112 / 85 keys on the piano, which might address your question, and welcome to make your own variation with your piano technique. https://musescore.com/user/27136270/scores/13852300
Comment: See also: the Stuart & Sons [108 Key Piano](https://www.stuartandsons.com/108keys.html).
Answer: replete's answer is correct that the original reason was to have a bigger range, as needed for some organ music. However, I don't think that's the reason those Imperial models are so sought-for over all these years – actually playing the lowest notest is scarcely musically useful.
The reason why people want Bösendorfer Imperial is that they sound awesome, even when the low strings aren't played. This probably has two main reasons:

The big sound frame is better at transmitting all frequencies, in particular those on the low end of the regular range. These strings aren't already at the very limit of what the resonator can do, like they are on many other pianos, but still in the range of what it can comfortably do, so thundering octaves actually thunder and don't just "clank".
The low strings give a denser sympathetic-resonance spectrum, when the pedal is pushed. As a result, a Bösendorfer has a richer sound even in high, soft, legato passages.
Comment: Plus to a pianist, a Bosendorfer is like a 2-ton pickup to a Texan :-)
Answer: These extended Bösendorfer ranges go back to Busoni's day. He wanted to match the range of pipe organs, as he was making transcriptions of J. S. Bach's organ works at the time.
Comment: @CarlWitthoft It only makes sense that they continue to make them because people buy them.
Comment: And then somebody built an organ with a 64' stop...
Answer: Yep.  There's of course another reason than cannot be underestimated: bling.
Comment: Hey, I live in Bösendorfer's home town.  You can't tell me that they don't sell their image.
Comment: I don't doubt that they promote their own image, but on the other hand, have you ever tried playing one?
Comment: @DavidK - can't say I have.  I'm sure they sound great.  But honestly- how often do we need these notes?
Comment: I believe the one I tried had just the usual 88 notes. But they all sounded great from one end of the keyboard to the other. That makes an astoundingly good-sounding piano. Also an astoundingly high price.
Comment: Oh, I thought you meant one with extended bass.  I've played the normal 88 keyed ones.  Yes, they are very nice modern pianos, and beautifully made too.


Are questions about industrial optics on topic?

Question: Recently I saw two questions pop up that didn't jump out as photography themed: What does "distortion <XX%" mean in lens specs? and How to read a lens spot diagram?. After a response from the poster, it looks like they are on lenses that are used for machine vision. I am unfamiliar with this, but this brings up the discussion point - are questions about lenses uses for industrial applications on topic?
Answer: I think we should apply the same rule as for video:

Can I use this information in still photography?

If it's very specific to machine vision — about optics, techniques, or terminology not applicable to still photography? Then it's probably not right for here.
I don't know about theses particular questions, but I'd love to see them answered in a way that relates these technical diagrams to those more typically used in photography. That way, I'd learn something.
Comment: I think it's reasonable to ask for a lot more background than these questions have.
Comment: I think when it comes to answering questions about optics, the results can always edify photographers. The lens in question was used for machine vision, however the question was not about machine vision...it was about the nature of optics and a photographic lens (i.e. something that projects a virtual image, with the ability to adjust aperture, focus, and maybe zoom. The lens design looked VERY similar to a DSLR lens.) If the question had been about how to use the lens for machine vision processing, I would agree, its off topic...that was not the case. Machine vision only came up in a comment.
Comment: I agree. I don't know enough about machine vision, and the poster hasn't given enough supporting details - for me to really decide if  these relate to photography at all. We will see I guess.
Answer: My thought process is this:

If we consider a question like this on topic, would we not be inviting any and all questions about optic and optical devices to be asked and answered here?
Wouldn't the questions given as examples fit better on a physics or engineering stack exchange site?

If we open up to all optics questions, are we prepared and willing to answer questions about microscopes, telescopes, etc? I only have a general understanding(if that) of machine vision, so I could be way off, but I am leaning towards off topic.
Comment: Questions about microscopes and telescopes should indeed be on-topic, as people use both devices to do photography quite frequently. I myself am a huge fan of astrophotography, and if I had the time and money, photographing the microscopic world would probably also be a hobby. I don't think either of those should be off topic when the questions are about optics or photography in relation to them. If people cannot come to PhotoSe with questions about optics, even when its marginally related to photography (machine vision is on the border), where else can they go?
Comment: How lenses project images is something the people on this forum seem well qualified to answer. Discussions about the virtual image projected by a lens, be it for machine vision, a DSLR, or a telescope, are all discussions about the same exact thing, and all the same physics apply.
Comment: I think the [Pee-Wee Herman Rule](http://blog.stackoverflow.com/2010/11/the-pee-wee-herman-rule/) might apply here as well. The asker of that question came to this site hoping it would be a place he could get an answer, and while he may be the nerdy suit, he isn't playing way, way out of bounds. I feel inclined to give him the benefit of the doubt for now, rather than chase him off right away and eliminate any chance he could become a welcome, contributing member of our community, particularly given that his question is something we are qualified to answer.
Comment: "where else can they go" I was suggesting either the physics site or an engineering SE site. I haven't looked to far into it, but I think we have some of these. I don't want to chase off contributing members either.. but keep in mind I tried asking him a question yesterday on one of the questions and still haven't heard a response. The other, as you already agreed with - we are left with open questions still. If we are following mr. hermans rules - I don't see a large potential for contribution. Maybe the user has great knowledge that no one else here does though, so there could be that too.
Comment: It doesn't need to be a "large" potential, just a potential. We could close and migrate the question to either the physics or engineering site, however before we do, I think we should at least give it a chance here. I guess my point is, when it comes to *marginally* off-topic questions, we should give askers the benefit of the doubt first, rather than just closing without a chance. We have had a variety of "science of optics and image processing" questions here on PhotoSE, from color theory to aspects of human sight. I think such questions are beneficial in small amounts.


Why can't pure water conduct electricity since it can be reduced at cathode and oxidised at anode?

Question: We all know that pure water can't conduct electricity. But during electrolysis, if add a small amount of $\ce{HCl}$ acid inside, water could be decomposed to hydrogen gas and oxygen gas, as it is reduced at the cathode and oxidised at the anode. So why can't pure water just conduct electricity by electrolysis?
Answer: Indeed, water can conduct electricity by electrolysis. But this is hampered by the fact that water has very high resistance. From Electrolysis of water:

Electrolysis of pure water requires excess energy in the form of
  overpotential to overcome various activation barriers. Without the
  excess energy the electrolysis of pure water occurs very slowly or not
  at all. This is in part due to the limited self-ionization of water.
  Pure water has an electrical conductivity about one millionth that of
  seawater.

And from Self-ionization of water we can see how small it is:

Water molecules dissociate into equal amounts of $\ce{H3O+}$ and $\ce{OH-}$, so their concentrations
  are equal to 1.00×10−7 mol∙dm-3 at 25 °C
Answer: Pure water has a very high resistivity, on the order of 18 MOhm/cm.  This effectively means that any applied potential is going to be converted into thermal energy.
A side note, oxidation of an $\ce{HCl}$ (or any salt with chloride ions) solution will produce $\ce{Cl_2}$ gas, so electrolysis of these solutions should be performed in a well ventilated area.
Answer:
Pure water cannot conduct electricity fundamentally because of lack of rapid ion transport inside bulk solution.
In fact, pure water electrolysis has been achieved, by using nanogap electrochemical cells, where the distance between two electrodes less than Debye-length of water (less than 100nm!). But the fundamental mechanism has been changed significantly.

===============

Lack of rapid ion transport in traditional electrolyzer.

We take cathode and H3O+ ions as an example. Initially near the cathode surface water molecules can be dissociated into H3O+ and OH- ions. H3O+ ions obtain electrons from cathode leading to hydrogen evolution; while newly-generated OH- ions can only transport very slowly through the bulk solution by slow diffusion or hopping process. These lead to local OH- ions accumulation (so that the solution near cathode turns alkaline) especially at the cathode surface, reducing the reaction rate of hydrogen evolution and thus water splitting. In other words, the reaction becomes very slow or even self-limited, showing a large equivalent resistance between the cathode and the anode. That is why pure water in macrosystem cannot be split efficiently.

Pure water electrolysis in Nanogap cells

In pure water, when the counter-electrode is placed within the Debye-length, double layer regions of the cathode and the anode are overlapping with each other so that high electric field exists in the entire gap. Still at cathode, newly-generated OH- ions can be migrated rapidly from cathode towards anode due to large electric field in the entire gap. When the gap distance is small enough, initially the transport rate can be even higher than the electron-transfer rate. Once OH- ions are generated, they are immediately drawn from cathode to anode, leading to such OH- ions waiting for electron-transfer at the anode, rather than accumulated at the cathode. In this way, the whole reactions would continue even in pure water, but now are limited by electron-transfer.
https://pubs.acs.org/doi/abs/10.1021/acsnano.7b04038
Answer: A solution conducts current when positive and negative ions are randomly dissolved in it. Pure water doesn't have enough ions but when you add $\ce{HCl}$ you add a strong electrolyte so, after the addition, solution can conduct electricity very well. However you can perform an electrolysis even without $\ce{HCl}$ but this is a very slow process because even if there are positive and negatives ions (and this could induce you to think that the pure water will conduct current!) the positive ions are near the negative electrode (the cathode) to be reduce on the other hand the negative ions are near the positive electrode (the anode) to be oxidise. So in fact you mustn't imagine a solution of positive and negative ions like in a solution of a true strong electrolyte but two bunch of ions, positive in the anode and negative near the cathode, so the current can't flow very well. This is why pure water can't conduct electricity even during the electrolysis when there are many ions in the solution.
Answer: IN pure water there is no chance for electricity conduction as it has no free ions.It contains only $\ce{H2O}$ molecules. For electricity conductance, there should be ions present. In the case you are talking about some drops of $\ce{H2SO4}$ is added for the conduction of electricity.
Answer: Pure water does not conduct electricity because there are no suspended particles of metals such as Iron and Copper. Pure water also has lack of zinc. Ions are even not present in pure water. We can make water conductive by adding drops of Sulphuric Acid.
Comment: Welcome to Chemistry.SE! Take the [tour] to get familiar with this site. Mathematical expressions and equations can be [formatted](http://meta.chemistry.stackexchange.com/q/86/4945) using $\LaTeX$ syntax. For more information in general have a look at the [help]. At the moment this reads more like a comment than an actual answer - could you elaborate a little more. With a bit more rep, [you will be able to post comments](http://chemistry.stackexchange.com/privileges/comment) on any question/answer.
Comment: It is quite uncommon for water to contain suspended solid metallic particles. Metallic elements in a sample of water are almost always present in the form of dissolved ions.
Answer: Pure Water can't conduct electricity because it has no free ions. But when water is contaminated, it increases the ionic level of it(then its no longer a pure water)-that's why you see waters conducting electric current and you got electrocuted by it.


Basic Relation save

Question: I have two sections:

Drinks
Ingredients

I have a relation/entry field set on the drinks. So for example, two entries in the ingredients section are related to a specific drink.
My question:
I have a guest entries form, which submits new ingredients and I want to relate this (or these..) ingredient(s) to the current drink. How would I go about doing this?
Creating the ingredient itself is not the problem. The problem is relating it to the drink.
For example, is there a hidden input where I can pass along a new array?
Thanks in advance,
Steve
Answer: You'd use this syntax:
<code><input type="hidden" name="fields[fieldHandle][]" value="123" />
</code>
Note the value should be the ID of the entry you want related. There's a handy guide here for the front-end syntax for all of Craft's field types: https://straightupcraft.com/articles/craft-cms-field-guide-twig?view=input

Basic Relation save


How do I beat someone taller with longer legs?

Question: I train taekwondo and I don't know what to do.
I have to fight against someone taller, with longer legs than me.
If I get too close, they either hit me or push me away.
They can still kick me when I'm too far away to kick them.
Do you know some kind of trick I could use.
Answer: They will continue to be able to stop you with a lead leg sidekick if they control your range. You can bait them to kick by footwork, faking, or by offering a target (i.e. Squaring your body to them) then evading (stepping out at an angle) and countering (round kick to body, crescent kick to head).You will need good footwork to avoid their technique and get inside their range- hit them- then get back out. When I get inside a taller person's range I use a lot of quick punching before pulling back.
Answer: If you limit yourself to kicking, you're in trouble unless you're really fast.
Against a person who depends on long range kicks, i would normally try to get inside their range, or parry a kick nage-ashe to turn them around, come in close for kidney shots, then get out of range again before they recover their balance.
As ksp08 says, you need to have good footwork and be able to bait them effectively.


What is the history of the use of "foo" and "bar" in source code examples?

Question: Why do many code examples, especially tutorials, use the names "Foo" and "Bar" so often? It is almost a standard.
For example:
<code>void foo(char* bar) {
  printf("%s", bar);
}
</code>
Answer: Foo and bar come from the US Army WWII acronym FUBAR, "F-ed Up Beyond All Recognition".  A whole family of these terms came into widespread use during the North African and Sicilian campaigns (1942-43).  Rick Atkinson's excellent Day of Battle: The War in Sicily and Italy, 1943-1944 gives a list of these.  For instance a JANFU is a "Joint Army Navy F Up", such as the incident on 11 July 1943 when the invasion fleet for Operation Husky shot down 23 Army Air Force C-47 transports carrying paratroopers to reinforce the beachhead.
Update: Wikipedia has a list of related acronyms that includes some the original WWII ones listed by Atkinson.
Any programmer will understand the motivation for using foo and bar to name variables.  They certainly have been part of the C/UNIX culture from the start, and as @Walter Mitty points out, predated it.
Update (10/5/2009): Here's Atkinson's description:

Their pervasive "civilianness" made them wary of martial zeal.  "We were not romantics filled with cape-and-sword twaddle," wrote John Mason Brown, a Navy Reserve lieutenant headed to Sicily. "The last war was too near for that." Military life inflamed their ironic sensibilities and their skepticism.  A single crude acronym that captured the soldier's lowered expectations -- SNAFU, "situation normal, all fucked up" -- had expanded into a vocabulary of GI cynicism: SUSFU (situation unchanged, still fucked up); FUMTU (fucked up more than usual); JANFU (joint Army-Navy fuck-up); JAAFU (joint Anglo-American fuck-up); FUAFUP (fucked up and fucked up proper); and FUBAR (fucked up beyond all recognition) [Atkinson, p. 36].

Update (11/23/2011): @Hugo has a fantastic list of the non-military antecedents.
Comment: @Mark, The German Wikipedia (de.wikipedia.org/wiki/Fubar), suggests this might be a pseudoetymology. It also points to antecedents like the "SILENCE IS FOO" sign in Warner Brother's 1938 cartoon "The Daffy Doc".
Comment: @Jim Ferrans: While FUBAR probably influenced the use of "bar" with "foo", there is strong evidence that "foo" by itself well predates WWII, with references at least back to the 1930s, as your comment indicates.  It might be good to mention that in the body of your answer.
Comment: To add to the etymology: "FUBAR may have been influenced by the German word furchtbar, meaning terrible. It is pronounced with a soft cht, and probably made the transition during World War II"
Comment: Yes, foo definitely predates WWII. In fact, I've found an MIT newspaper piece from 1938 that tells us how common it was: "As an expletive, of course, "foo!" has a definite and probably irreplaceable position in our language, although we fear that the excessive use to which it is currently subjected may well result in its falling into an early (and, alas, a dark) oblivion." See my answer for more and a 1937 reference in the same newspaper: http://programmers.stackexchange.com/questions/69788/using-foo-and-bar-in-examples/80609#80609
Answer: I think it's the phonetic pronouncation of fubar.
Which stands for:

F*cked
Up
Beyond
All
Repair
Comment: repair? nah .. recognition
Comment: Repair or Recognition ;P
Comment: "Fouled" is often used when needing to be polite.
Comment: Just a note that there's strong evidence (see RFC 3092, the Jargon File, and other answers here) that "foo" was used as a placeholder nonsense word in the 1930s, well before FUBAR came into military slang in the WWII era.
Comment: It's "recognition".  See quote from Rick Atkinson's Day of Battle here: http://stackoverflow.com/questions/262271/where-did-foo-and-bar-come-from/934884#934884
Comment: Sometimes "Fouled Up Beyond All Recovery" (Or f*cked)
Comment: @Daniel Pryden, I agree, see my answer for plenty of references: http://programmers.stackexchange.com/questions/69788/using-foo-and-bar-in-examples/80609#80609
Answer: The New Hacker's Dictionary has a very good entry on this - and I consider it to be a better resource for this kind of thing than Wikipedia:

metasyntactic variable /n./
A name used in examples and understood to stand for whatever thing is under discussion, or any random member of a class of things under discussion. The word foo is the canonical example. To avoid confusion, hackers never (well, hardly ever) use `foo' or other words like it as permanent names for anything. In filenames, a common convention is that any filename beginning with a metasyntactic-variable name is a scratch file that may be deleted at any time.
To some extent, the list of one's preferred metasyntactic variables is a cultural signature. They occur both in series (used for related groups of variables or objects) and as singletons. Here are a few common signatures:
foo, bar, baz, quux, quuux, quuuux...:
          MIT/Stanford usage, now found everywhere (thanks largely to early versions of this lexicon!). At MIT (but not at Stanford), baz dropped out of use for a while in the 1970s and '80s. A common recent mutation of this sequence inserts qux before quux.
bazola, ztesch:
          Stanford (from mid-'70s on).
foo, bar, thud, grunt:
          This series was popular at CMU. Other CMU-associated variables include gorp.
foo, bar, fum:
          This series is reported to be common at XEROX PARC.
fred, barney:
          See the entry for fred. These tend to be Britishisms.
corge, grault, flarp:
          Popular at Rutgers University and among GOSMACS hackers.
zxc, spqr, wombat:
          Cambridge University (England).
shme
          Berkeley, GeoWorks, Ingres. Pronounced /shme/ with a short /e/.
snork
          Brown University, early 1970s.
foo, bar, zot
          Helsinki University of Technology, Finland.
blarg, wibble
          New Zealand.
toto, titi, tata, tutu
          France.
pippo, pluto, paperino
          Italy. Pippo /pee'po/ and Paperino /pa-per-ee'-no/ are the Italian names for Goofy and Donald Duck.
aap, noot, mies
          The Netherlands. These are the first words a child used to learn to spell on a Dutch spelling board.
Of all these, only 'foo' and 'bar' are universal (and baz nearly so). The compounds foobar and `foobaz' also enjoy very wide currency.
Some jargon terms are also used as metasyntactic names; barf and mumble, for example. See also Commonwealth Hackish for discussion of numerous metasyntactic variables found in Great Britain and the Commonwealth.
Comment: Have to say, I'm from NZ and I've never heard of 'blarg' OR 'wibble'.
Comment: That was one pretty good. It's elaborate.Thanks dude.
Comment: OMG, my QL account is qux. Shocked...
Comment: @Colin - I altered the link to a different site, since the existing one was offline.
Comment: I found some other interesting metasyntactic variables from an MIT 1964 paper about LISP (that of course also had foo): chi / boston new york / spinach butter steak / foo crock glitch / poot toop / toot toot / isthisatrivialexcercise / ploop flot top / snap crackle pop / one two three / plane sub thresher. See my answer for more info: http://programmers.stackexchange.com/questions/69788/using-foo-and-bar-in-examples/80609#80609
Answer: Wikipedia gives this definition of Metasyntactic Variable :

In computer science, programmers use metasyntactic variables to
  describe a placeholder name or an alias term commonly used to denote
  the subject matter under discussion or an arbitrary member of a class
  of things under discussion. The use of a metasyntactic variable is
  helpful in freeing a programmer from creating a logically named
  variable, which is often useful when creating or teaching examples of
  an algorithm. The word foo is the principal example.
  The term
  "metasyntactic variable" is primarily found in informal literature. It
  is sometimes also used as a synonym for metavariable.
  Any symbol or
  word which does not violate the rules of the language can be used as a
  metasyntactic variable, but nonsense words are commonly used. The same
  concept is employed in other fields where it is expressed by terms
  such as schematic variable (see logical form).
  By mathematical
  analogy: A metasyntactic variable is a word that is a variable for
  other words, just as in algebra letters are used as variables for
  numbers.

The article also gives common examples of such variables in different programming languages :

C
  In the following example of the C programming language the
  function name foo and the variable name bar are both metasyntactic
  variables. Lines beginning with // are comments.

<code>// The function named foo
int foo(void)
{
   // Declare the variable bar and set the value to 1
   int bar = 1;

   return bar;
}
</code>

Python
Spam, ham, and eggs are the principal metasyntactic
  variables used in the Python programming language.[5] This is a
  reference to the famous comedy sketch, Spam, by Monty Python, the
  eponym of the language.[6] In the following example spam, ham, and
  eggs are metasyntactic variables and lines beginning with # are
  comments.

<code># Define a function named spam
def spam():

    # define the variable ham
    ham = "Hello World!"

    #define the variable eggs
    eggs = 1

    return
</code>

Ruby
In the following example the baz, foo, and bar are metasyntactic
  variables and lines beginning with # are comments.

<code># Declare the variable foo and set equal to 1
foo = 1

# Declare the variable bar and set equal to 2
bar = 2

# Declare the method (function) named baz, which prints the text 'Hello world'
def baz
   puts 'Hello world'
end
</code>
Answer: Here is wikipedia's answer:

The terms foobar, foo, bar, and baz,
  are common placeholder names (also
  referred to as metasyntactic
  variables) used in computer
  programming or computer-related
  documentation. They are commonly used
  to represent unknown values, typically
  when describing a scenario where the
  purpose of the unknown values are
  understood, but their precise values
  are arbitrary and unimportant. The
  terms can be used to represent any
  part of a complicated system or idea,
  including the data, variables,
  functions, and commands. The words
  themselves have no meaning in this
  usage, and are merely logical
  representations, much like the letters
  x and y are used in algebra. Foobar is
  often used alone; foo, bar, and baz
  are usually used in that order, when
  multiple entities are needed.
Foo has entered the English language
  as a neologism and is considered by
  many to be the canonical example of a
  metasyntactic variable.[citation
  needed] It is used extensively in
  computer programming examples
  (sometimes expressed as "for once
  only") and pseudocode. Eric S. Raymond
  has called it an "important hackerism"
  alongside kludge and cruft.[1]

http://en.wikipedia.org/wiki/Foo
And from RFC 3092:

When used in connection with 'bar' it is generally traced to the
        WW II era Army slang acronym FUBAR ('Fucked Up Beyond All
        Repair'), later modified to foobar.  Early versions of the Jargon
        File [JARGON] interpreted this change as a post-war
        bowdlerization, but it now seems more likely that FUBAR was itself
        a derivative of 'foo' perhaps influenced by German 'furchtbar'
        (terrible) - 'foobar' may actually have been the original form.
For, it seems, the word 'foo' itself had an immediate prewar
        history in comic strips and cartoons.  In the 1938 Warner Brothers
        cartoon directed by Robert Clampett, "The Daffy Doc", a very early
        version of Daffy Duck holds up a sign saying "SILENCE IS FOO!"...(snip)

http://www.faqs.org/rfcs/rfc3092.html
Comment: or you could just admit it comes from fubar = '"f" up beyond all recognition'
Comment: @Jonathan Fingland: No it doesn't.  (In fact, "foo" probably predates both "foobar" and "FUBAR".)  See RFC 3092 and the Jargon File entry for "foo".
Comment: @Daniel, Excellent reference. Added
Answer: tl;dr

"Foo" and "bar" as metasyntactic variables were popularised by MIT and DEC, the first references are in work on LISP and PDP-1 and Project MAC from 1964 onwards.

Many of these people were in MIT's Tech Model Railroad Club, where we find the first documented use of "foo" in tech circles in 1959 (and a variant in 1958).

Both "foo" and "bar" (and even "baz") were well known in popular culture, especially from Smokey Stover and Pogo comics, which will have been read by many TMRC members.

Also, it seems likely the military FUBAR contributed to their popularity.

The use of lone "foo" as a nonsense word is pretty well documented in popular culture in the early 20th century, as is the military FUBAR. (Some background reading:
FOLDOC
FOLDOC
Jargon File
Jargon File
Wikipedia
RFC3092)

OK, so let's find some references.
STOP PRESS! After posting this answer, I discovered this perfect article about "foo" in the Friday 14th January 1938 edition of The Tech ("MIT's oldest and largest
newspaper & the first newspaper published on the web"), Volume LVII. No. 57, Price Three Cents:

On Foo-ism
The Lounger thinks that this business of Foo-ism has been carried too far by its misguided proponents, and does hereby and forthwith take his stand against its abuse.
It may be that there's no foo like an old foo, and we're it, but anyway, a foo and his money are some party. (Voice from the bleachers- "Don't be foo-lish!")
As an expletive, of course, "foo!" has a definite and probably irreplaceable position in our language, although we fear that the excessive use to which it is currently subjected may well result in its falling into an early (and, alas, a dark) oblivion. We say alas because proper use of the word may result in such happy incidents as the following.
It was an 8.50 Thermodynamics lecture by Professor Slater in Room 6-120. The professor, having covered the front side of the blackboard, set the handle that operates the lift mechanism, turning meanwhile to the class to continue his discussion. The front board slowly, majestically, lifted itself, revealing the board behind it, and on that board, writ large, the symbols that spelled "FOO"!

The Tech newspaper, a year earlier, the Letter to the Editor, September 1937:

By the time  the  train  has  reached  the station  the  neophytes  are  so  filled with  the  stories  of  the  glory  of  Phi Omicron  Omicron,  usually  referred  to as  Foo,  that  they  are  easy  prey.
...
It  is  not  that  I  mind  having  lost my  first  four  sons  to  the  Grand  and Universal  Brotherhood  of  Phi  Omicron  Omicron,  but  I  do  wish  that  my fifth  son,  my  baby,  should  at least  be warned  in  advance.
Hopefully  yours,
Indignant  Mother  of  Five.

And The Tech in December 1938:

General  trend  of  thought  might  be best  interpreted  from  the  remarks
made  at  the  end  of  the  ballots.  One vote  said,  '"I don't  think  what  I  do  is any  of  Pulver's  business,"  while another  merely  added  a  curt  "Foo."

The first documented "foo" in tech circles is probably 1959's Dictionary of the TMRC Language:

FOO:  the sacred syllable (FOO MANI PADME HUM); to be spoken only when under inspiration to commune with the Deity. Our first obligation is to keep the Foo Counters turning.

These are explained at FOLDOC. The dictionary's compiler Pete Samson said in 2005:

Use of this word at TMRC antedates my coming there. A foo counter could simply have randomly flashing lights, or could be a real counter with an obscure input.

And from 1996's Jargon File 4.0.0:

Earlier versions of this lexicon derived 'baz' as a Stanford corruption of bar. However, Pete Samson (compiler of the TMRC lexicon) reports it was already current when he joined TMRC in 1958. He says "It came from "Pogo". Albert the Alligator, when vexed or outraged, would shout 'Bazz Fazz!' or 'Rowrbazzle!' The club layout was said to model the (mythical) New England counties of Rowrfolk and Bassex (Rowrbazzle mingled with (Norfolk/Suffolk/Middlesex/Essex)."

A year before the TMRC dictionary, 1958's MIT Voo Doo Gazette ("Humor suplement of the MIT Deans' office") (PDF) mentions Foocom, in "The Laws of Murphy and Finagle" by John Banzhaf (an electrical engineering student):

Further research under a joint Foocom and Anarcom grant expanded the law to be all embracing and universally applicable: If anything can go wrong, it will!

Also 1964's MIT Voo Doo (PDF) references the TMRC usage:

Yes! I want to be an instant success and snow customers. Send me a degree in:
...

Foo Counters

Foo Jung

But let's remember this question is about code examples, so let's find "foo", "bar" and "foobar" published in code.
So, Jargon File 4.4.7 says of "foobar":

Probably originally propagated through DECsystem manuals by Digital Equipment Corporation (DEC) in 1960s and early 1970s; confirmed sightings there go back to 1972.

The first published reference I can find is from February 1964, but written in June 1963, The Programming Language LISP: its Operation and Applications by Information International, Inc., with many authors, but including Timothy P. Hart and Michael Levin:

Thus, since "FOO" is a name for itself, "COMITRIN" will treat both "FOO" and "(FOO)" in exactly the same way.

Also includes other metasyntactic variables such as: FOO CROCK GLITCH / POOT TOOR / ON YOU / SNAP CRACKLE POP / X Y Z
I expect this is much the same as this next reference of "foo" from MIT's Project MAC in January 1964's AIM-064, or LISP Exercises by Timothy P. Hart and Michael Levin:

car[((FOO . CROCK) . GLITCH)]

It shares many other metasyntactic variables like: CHI / BOSTON NEW YORK / SPINACH BUTTER STEAK / FOO CROCK GLITCH / POOT TOOP / TOOT TOOT / ISTHISATRIVIALEXCERCISE / PLOOP FLOT TOP / SNAP CRACKLE POP / ONE TWO THREE / PLANE SUB THRESHER
For both "foo" and "bar" together, the earliest reference I could find is from MIT's Project MAC in June 1966's AIM-098, or PDP-6 LISP by none other than Peter Samson:

EXPLODE, like PRIN1, inserts slashes, so (EXPLODE (QUOTE FOO/ BAR)) PRIN1's as (F O O // /  B A R) or PRINC's as (F O O /   B A R).

Some more recallations.
@Walter Mitty recalled on this site in 2008:

I second the jargon file regarding Foo Bar. I can trace it back at least to 1963, and PDP-1 serial number 2, which was on the second floor of Building 26 at MIT. Foo and Foo Bar were used there, and after 1964 at the PDP-6 room at project MAC.

John V. Everett recalls in 1996:

When I joined DEC in 1966, foobar was already being commonly used as a throw-away file name. I believe fubar became foobar because the PDP-6 supported six character names, although I always assumed the term migrated to DEC from MIT. There were many MIT types at DEC in those days, some of whom had worked with the 7090/7094 CTSS. Since the 709x was also a 36 bit machine, foobar may have been used as a common file name there.
Foo and bar were also commonly used as file extensions. Since the text editors of the day operated on an input file and produced an output file, it was common to edit from a .foo file to a .bar file, and back again.
It was also common to use foo to fill a buffer when editing with TECO. The text string to exactly fill one disk block was IFOO$HXA127GA$$. Almost all of the PDP-6/10 programmers I worked with used this same command string.

Daniel P. B. Smith in 1998:

Dick Gruen had a device in his dorm room, the usual assemblage of B-battery, resistors, capacitors, and NE-2 neon tubes, which he called a "foo counter."  This would have been circa 1964 or so.

Robert Schuldenfrei in 1996:

The use of FOO and BAR as example variable names goes back at least to 1964 and the IBM 7070.  This too may be older, but that is where I first saw it.  This was in Assembler.  What would be the FORTRAN integer equivalent? IFOO and IBAR?

Paul M. Wexelblat in 1992:

The earliest PDP-1 Assembler used two characters for symbols (18 bit machine) programmers always left a few words as patch space to fix problems. (Jump to patch space, do new code, jump back)  That space conventionally was named  FU: which stood for Fxxx Up, the place where you fixed Fxxx Ups.  When spoken, it was known as FU space. Later Assemblers ( e.g. MIDAS allowed three char tags so FU became FOO, and as ALL PDP-1 programmers will tell you that was FOO space.

Bruce B. Reynolds in 1996:

On the IBM side of FOO(FU)BAR is the use of the BAR side as Base Address Register; in the middle 1970's CICS programmers had to worry out the various xxxBARs...I think one of those was FRACTBAR...

Here's a straight IBM "BAR" from 1955.

Other early references:

1967 foo bar MIT AIM-127

1967 foo bar MIT AIM-127a

1965 foo MIT Tech Engineering News

1968 foo baz DEC

1971 FOO BAR UCLA-NMC RFC269

1972 FOO MIT AI

1972 FOO MIT AI HAKMEM (PDF scan)

1972 FOO DEC

1973 FOO DEC

1973 foo bar International Joint Council on Artificial Intelligence

1975 foo bar International Joint Council on Artificial Intelligence

1977 Foobar

1978 Foobar

1978 Moby Foobar in Software Wars

I haven't been able to find any references to foo bar as "inverted foo signal" as suggested in RFC3092 and elsewhere.
Here are a some of even earlier F00s but I think they're coincidences/false positives:

1959 "FOO 31 IBM-704 Bettis Plant Uses a least squares technique" U.S. Atomic Energy Commission

1960 FOO (FO Out, F1, F2, FOO, FOI) "Digital computer and control engineering"

1967 FOO?
Answer: using words like "foo" and "bar" make you focus on the concept not on what you can grasp based on the terms you know.  For example:
<code>public abstract class Animal
{
    public abstract void speak();
}

public class Cat
    extends Animal
{
    public abstract void speak()
    {
        System.out.println("meow");
    }
}

public class Dog
    extends Animal
{
    public abstract void speak()
    {
        System.out.println("bark");
    }
}
</code>
The above code lets you fall back on your knowledge of real world things.
If you are trying to explain a concept where the important part is not what is being done (printing meow or bark for example) but on how it is being done then removing the parts that you are familiar help:
<code>public abstract class Foo
{
    public abstract void star();
}

public class Bar
    extends Foo
{
    public abstract void star()
    {
        System.out.println("A");
    }
}

public class Car
    extends Foo
{
    public abstract void star()
    {
        System.out.println("b");
    }
}
</code>
Now you have to focus on what is really happening, you are no longer able to guess at what is going to happen.
So, the short version is, that foo, bar, and the like, are used to stress concepts where the content doesn't really matter but the idea does.
Comment: Yes, but why Foo and Bar specifically? Why not Lorum and Ipsum?
Comment: ah, a real answer!
Comment: http://en.wikipedia.org/wiki/Foo could be accurate...
Comment: @TofuBeer Yep, they're "metasyntactic variables". @masher see my answer with loads of references as to why Foo and Bar and not Lorem and Ipsum. http://programmers.stackexchange.com/questions/69788/using-foo-and-bar-in-examples/80609#80609 In fact, there are loads of different metasyntactic variables that have been used over the years, and in different places.
Answer: From http://en.wikipedia.org/wiki/Foobar
In technology, the word was probably originally propagated through system manuals by Digital Equipment Corporation in 1960s and early 1970s. Another possibility is that foobar evolved from electronics, as an inverted foo signal. This is because if a digital signal is active low (so a negative or zero-voltage condition represents a "1") then a horizontal bar is commonly placed over the signal label. The Jargon File makes a case that foo possibly predates FUBAR
Comment: this does not explain the why
Comment: I've found plenty of references of first "foo" and later "bar" from MIT and also DEC (both in Massachusetts), in their work on LISP and the PDP-1 and Project MAC from 1964 onwards. It's a nice idea, but I couldn't find any reference to an "inverted foo signal". More here: http://programmers.stackexchange.com/questions/69788/using-foo-and-bar-in-examples/80609#80609
Answer: From the Jargon Files http://www.catb.org/jargon/html/F/foo.html
foo: /foo/

interj. Term of disgust.
[very common] Used very generally as a sample name for absolutely anything, esp. programs and files (esp. scratch files).
First on the standard list of metasyntactic variables used in syntax examples. See also bar, baz, qux, quux, garply, waldo, fred, plugh, xyzzy, thud.

bar: /bar/, n.

[very common] The second metasyntactic variable, after foo and before baz. "Suppose we have two functions: FOO and BAR. FOO calls BAR...."
Often appended to foo to produce foobar.
Answer: According to http://en.wikipedia.org/wiki/Foo:

The terms' origins are not known with certainty, and several anecdotal
  theories have been advanced to identify them. Foobar may derive from
  the vulgar military acronym FUBAR, or it may have gained popularity
  due to the fact that it is pronounced the same.
Answer: I second the jargon file regarding Foo Bar.
I can trace it back at least to 1963, and PDP-1 serial number 2, which was on the second floor of Building 26 at MIT.  Foo and Foo Bar were used there, and after 1964 at the PDP-6 room at project MAC.
Comment: +1 for witnessing one of the earliest uses of Foo Bar :) How exactly were Foo and Foo Bar actually used there?
Comment: PS I've included your quote in my big answer: http://programmers.stackexchange.com/questions/69788/using-foo-and-bar-in-examples/80609#80609
Answer: As far as I know, foo comes from foobar which is an alteration of "fubar", a military catch phraase that stands for "F***ed up beyond all recognition."
Then again, there may be other sources.
http://en.wikipedia.org/wiki/Foo
Answer: Foo and Bar (otherwise known as FUBAR...F***ed Up Beyond All Recognition) has just been used as standard generic names for things like classes, properties, method names, etc.
Basically the idea is to convey your code without as much extraneous information that could possibly get away from how the code works (i.e. we don't need to know your function is named AddUser to see the code and understand what it does if we rename it to Foo() ).
Answer: These are nonsense words that in most cases can be substituted with more relevant example words.  The words "foo" and "bar" are frequently used in programming when someone can't think of a good example.
If "foo" and "bar" are derived from FUBAR, why is it they are used by so many professionals in instruction examples when the examples resemble nothing being f'd up beyond recognition?
To me, the common use of these words inappropriately is what's so f'd up beyond recognition.
Comment: Note that just below the question is a banner: *We're looking for long answers that provide some explanation and context. Don't just give a one-line answer; explain why your answer is right, ideally with citations. Answers that don't include explanations may be removed.* Your answer offers little in the way of an explanation; currently it is merely an opinion.
Comment: There are many other short answers.  Why not provide an argument if you don't agree with what I'm saying instead of pointing out a technicality that doesn't apply?
Comment: edit in rev 2 made this answer even worse than it was before (though it was hard to imagine what could be worse): now it is just a repeats [another answer](http://programmers.stackexchange.com/a/69811/31260 "'stands for "F***ed up beyond all recognition."'") that has been posted 4 years ago


What are the transmutation circles in Fullmetal Alchemist based on, if anything?

Question: The transmutation circles in Fullmetal Alchemist always looked familiar to me, but I could never place my finger on why. What, if anything, are they based on?
Answer: This site has a note about "Squaring the circle", describing a utilization of circles:

Attributed to Michael Maier, a German alchemist from the 17th century. That gives you the generalized "simple" transmutation circle:

The symbols used in some of the more complex circles are old alchemic symbols or variations of them. I don't know of a complete list of them but some of them can be seen in Annibal Barlet's works or other symbols from the 17th century. The inscriptions themselves seem to mostly come from George Ripley's 12 Gates.
Answer: Circles are a relatively major thing in alchemy. Ouroboros symbols were sigils in alchemy dating back to Cleopatra, and they depict a serpent or dragon eating its own tail.

The symbols in the circle are mostly alchemic symbols. The one on the the bottom left on the outside looks like the symbol for iron ore or the symbol for male. Going clockwise from that is what looks like either copper ore or female, a symbol I can't identify, one of the symbols for regulus, another symbol I can't identify, and sal-ammoniac. (Source)
Some Renaissance alchemic images have circles with words in them.

Squaring the circle was another major part of Renaissance alchemic ideas. It was believed that this symbol plus a man and a woman in the circle was all that was needed to create a philosopher's stone. A full explanation can be seen here.

The Seal of Solomon is another similar image.
According to here:

In alchemy, the combination of the fire and water symbols (up and down triangles) is known as the Seal of Solomon. The symbol is representative of the combination of opposites and transmutation. By combining the alchemical symbols for fire (upwards triangle) and water (downwards triangle), the alchemical symbols for earth and air are also created. The downwards facing triangle is divided along the center by the base line of the opposite triangle. This is the alchemical symbol for earth. Conversely, the upwards triangle divided by the base line of the downwards triangle is the alchemical symbol for air. The Seal of Solomon is all that is unified in perfect balance; the Spirit Wheel.

It's seems to be pretty much a compilation of different alchemic elements.
Answer: Yes, those are the symbols for the four base elements. But there are also two more very important parts to the circle. The center point which represents origin, time and growth, as well as an outer circle that represents the womb, the ether and protection. There are many more aspects and details to Solomon's circle than that. In fact, for such a simple symbol it is quite complex.
Comment: This answer is relatively low on actual content and doesn't have any references. If you have a lot more to say which is relevant to the series, you're welcome to add another answer, but right now this looks like it's more intended as a comment on one of the existing answers.
Answer: I always thought it looked like the Seal of the Seven Archangels which is a protection symbol.  Seal Image
Comment: Please elaborate on your answer. One-line answers are discouraged, unless it fully answers the OP's question.
Answer: Based on information I read at another source, some of the circles utilize the elemental symbols. Take colonel mustangs, for example. Two triangles intersect, one representing air and one representing earth, two things necessary for a successful fire. Within these triangles is the triangle representing fire. The bigger triangles push past the boundaries of the circle that's attempting to contain it, symbolizing fires expansive nature. To accompany this are images of a fire and a salamander. There's a reason for the salamander but I didn't understand that as well as the other things I mentioned.
Answer: The seals in fma are based on the King Solomon seals of Kabbalah as we see the Sephirotic tree of life in the show. The Soloman seals are said to have magical properties such bringing wealth or repelling demons (there are like 50 different seals). These seals can only be activated by people who know how to use them (at least in the show). My theory is the people of Amestres mix alchemist symbols with magic (prayer) to produce energy using holy power.
Assuming the fma world acts mostly as ours we know something cannot be made from nothing i.e the conservation of mass. The way to go against this worldly law is by using a stone. The philosophers stone grants godlike ability but at a cost of a soul, bringing up the whole idea of how much is a soul really worth?
Father and the seven deadly sins are powered by souls like batteries but humans have only 1 such battery. This is where the series gets paranormal. It is through the literal power of God that alchemist can manipulate objects but the objects can never change their chemical properties or add mass to them "for creating something from nothing is God's work" and impossible. The 2nd laws of thermodynamics basically states that energy needs to be consumed for anything to happen, it could never be an endless stream of energy, it needs a source. There is an irreversibility towards natural processes. No human could go against God and cheat death.
We can further deduce this by looking at the people who opened the portal of truth. Once opened you are granted the ability to do alchemy with no seal and by simply clapping your hands together which kind of looks like praying (Ed even mentions it in the last episode). They cant ignore the conservation of mass but they can manipulate it without having to use any seals. Even this needs energy to do. They claim in the show it is the tectonic energy that is harvested through the earth which produces the energy needed. But they also claim one is all and all is one. This is a prerequisite to alchemy training. In theory if you are one with all, you are one with God because God is everything (we see this is most religions especially Hinduism) you are using the power of the world to force energy into mass.
The whole Dragon or Snake eating itself is a great analogy for the search for immorality, the holy grail, the power of God, the fountain of youth, etc. The whole FMA series is based off the idea that nothing last forever and death can be a beautiful thing. it is something we have to fight and accept at the same time.

The Gamer Psyche


Does Magnussen have any disorders?

Question: People here and on the Web generally have established that Sherlock is not a sociopath and that Moriarty most likely is a psychopath.
Can we say that Magnussen from Sherlock season 3 has any disorders of that kind? If we can, what'd be the grounds?
Answer: Magnussen is by far the least desirable characters, from the entire Sherlock series. I don't think he suffers from any disorder but he is definitely a megalomaniac. He loves to hog the limelight and is a complete totalitarian. Example, peeing in the fireplace:

MAGNUSSEN: ... you're so domesticated. All standing around, apologizing ...
  (He nods to Sherlock and then walks in between him and John towards the fireplace.)
MAGNUSSEN: ... keeping your little heads down.
  (He stands in front of the fireplace, facing it. The sound of him unzipping his trousers can be heard.)
MAGNUSSEN: You can do what you like here. No-one's ever going to stop you.
  (He looks down and the sound of him urinating into the fireplace can be heard. John blinks as if appalled and half-turns his head towards him. Sherlock keeps his head facing forward, his eyes fixed on the opposite wall.)
MAGNUSSEN: I've interests all over the world but, er, everything starts in England.(He looks down again as the last of his urine splashes on the grate in front of the fire.)
MAGNUSSEN: If it works here ...
  (He jiggles up and down as he 'shakes off' and then zips up his trousers.)

Though Sherlock acknowledges himself as a high functioning sociopath, Magnussen on the contrary acknowledges himself as a businessman. This is evident from the scene where armed police marksmen run towards Sherlock, John and Magnussen outside the appledore.

JOHN (looking round to his friend): Sherlock, what do we do?
  (He turns to look at the helicopter again.)
MAGNUSSEN (over his shoulder): Nothing! (He looks round at them.) There's nothing to be done! Oh, I'm not a villain. I have no evil plan. I'm a businessman, acquiring assets. You happen to be one of them!

On the whole, I thing Magnussen is just a malicious mogul who uses the mind mapping technique.
Source for transcript: Arianedevere

Does Magnussen have any disorders?


MapReduce on AWS

Question: Anybody played around with MapReduce on AWS yet? Any thoughts? How's the implementation?
Comment: How come when I asked questions like this they die in 4 secs with `not a real question` buls**it
Answer: It's easy to get started.
Here's a FAQ: http://aws.amazon.com/elasticmapreduce/faqs/
And here's the Getting Started Guide: http://docs.amazonwebservices.com/ElasticMapReduce/latest/GettingStartedGuide/
If you have an EC2 account already, you can enable MapReduce and have a sample application up and running in less than 10 minutes using the AWS Management Console.
I did the pre-packaged Word Count sample application, which returns a count of each word contained in about 20 MB of text.  You can provision up to 20 instances to run concurrently, though I just used 2 instances and the job completed in about 3 minutes.
The job returns a 300 KB alphabetized list of words and how often each word appears in the sample corpus.
I really like that MapReduce jobs can be written in my choice of Perl, Python, Ruby, PHP, C++, R, or Java.  The process was painless and straightforward, and the interface gives good feedback on the status of your instances and the job flow.
Be aware that, since AWS charges for a full hour when an instance is created, and since the MapReduce instances are automatically terminated at the end of the job flow, the cost of multiple fast-running job flows can add up quickly.
For example, if I create a job flow that uses 20 instances and returns results in 15 minutes, and then re-run the job flow 3 more times, I'll be charged for 80 hours of machine time even though I only had 20 instances running for 1 hour.
Comment: Our experiences as well, plus the slow start up time. It's only worth it if you have jobs that are likely to run for several hours.
Comment: The cluster is not necessarily automatically terminated, you can leave it running.
Answer: You also have the possibility to run MapReduce (Hadoop) on AWS with StarCluster. This tool configures the cluster for you and has the advantage that you don´t have to pay the extra Amazon Elastic MapReduce Price (if you want to reduce your costs) and you could create your own Image (AMI) with your tools (this could be good if the installation of the tools can´t be done by a bootstrap script).
Answer: It is very convenient because you don't have to administer your own cluster. You just pay per use so I think it is a good idea if you have a job that needs to run once in a while. We are running Amazon MapReduce just once a month so, for our usage, it is worth it.
However, as far as I can tell, a drawback of Amazon Map Reduce is that you can't tell which Operating System is running, or even its version. This caused me problems running c++ code that compiled with g++ 4.44, some of the OS images does not support cUrl library, etc.
If you don't need any special libraries for your use case, I would say go for it.
Answer: Good answer by MB.
To be clear: you can run Hadoop clusters in two ways:
1) Run it on Amazon EC2 instances. This means that you have to install it, configure it, terminate it, etc.
2) Run it using Elastic MapReduce, or EMR: this is an automated way to run an Hadoop cluster on Amazon Web Services. You pay a little extra on top of the basic cost for EC2, but you don't need to manage anything: just upload your data, then your algorithm, then crunch. EMR will shut down the instances automatically once your jobs are finished.
Best,
Simone
Answer: EMR is the best way to use available resources with a very little added cost over EC2 however you will how time saving and easy it is. Most of the MR implementation on Cloud are using this model i.e. Apache Hadoop on Windows Azure, Mortar Data etc.. I have worked on both Amazon EMR and Apache Hadoop on Windows Azure and found incredible to use.
Answer: Also, depending on the type / duration of jobs you plan to run, you can use AWS spot instances with EMR to get better pricing.
Answer: I am working with AWS EMR. It is pretty neat. I mean once you start up their cluster and login into their Master node. You can play around with the hadoop directory structure. And do pretty cool things.. If you have a edu account don;t forget to apply for a research grant. They give unto 100$ free credits to use their AWS.
Answer: AWS EMR is a good choice when you use S3 storage for your data.
It provides out of the box integration with S3 for loading files and posting processed files.
In use cases where you need to run the job on demand, you are saved from the cost of running the whole cluster all the time, this really helps you save on instance hours.
Leveraging the above advantage, one can use AWS lambda to spawn event driven clusters.

MapReduce on AWS


Would one have to be more than halfway to the Oort Cloud for the Sun to appear as bright as the full moon?

Question: Is this correct?  If the Sun is 400,000 times brighter than the full moon am I correct in figuring that one would have to be about 632AU from the Sun for it to appear as bright as the full moon.  If the Oort Cloud begins about 1000AU from the Sun, one would have to be more than 60% the way to the Oort Cloud for the Sun to appear as bright as the full moon.
Answer: Yes, brightness is inversely proportional to the square of the distance, and the square of 632 is about 400,000. It's probably appropriate to round the value to 1s.f. to give "600AU".  Of course, at that distance the sun appears point-like.
The distance to the Oort cloud is rather hard to define. It's not like you reach 1000 AU and see a Star Wars like "Asteroid field" of comet nuclei. For example Wikipedia gives a distance of 2000AU.
Comment: 1 significant figure.  We can round the distance figure the to the same degree that the brightness figure has been rounded.
Comment: Thanks.  I did not think of the Oort Cloud as a wall starting a 1000AU (I was using NASA's estimate).  I had pictured it as a few comet nuclei spread out thinly at that distance.  I also assumed getting deeper into the Cloud it was more like the asteroid belt between Mars and Jupiter, than Star Wars weaving and twisting between objects.
Comment: What does 1s.f. mean?
Comment: The Oort cloud actually begins at about 10,000 au.


On the Bitcoin testnet, will transactions with higher fees get mined quicker?

Question: I wonder if anyone here has spent enough time on the Bitcoin testnet to give me some insight on how the market forces there work. I am a teaching assistant in a university blockchain course with ~75 students, and I plan to start an assignment in a few days where students acquire testnet BTC from faucets and start crafting transactions. There are currently about 14,000 unconfirmed transactions in the testnet mempool, and I wonder whether you can avoid waiting long if you increase your fee. Larger fees would obviously help on the Bitcoin mainnet, but I'm less sure about how miners behave on the testnet.
Comment: Another issue people have seen is apparently where the faucet doesn't include a high enough fee, and so you have trouble getting your testnet coins in the first place.  In principle one could work around this with child-pays-for-parent, but this might be tricky for beginners.
Comment: Personally, I'd think twice about this plan.  There's a lot of possibility for frustration caused by issues outside the students' control, and frustration for you as you try to figure out how to address this while still keeping the assignment useful and not unduly penalizing students.  So, a different option would be to create a private testnet just for the class.
Answer: Because the testnet bitcoins have no financial value, the transaction fees aren't really an incentive for miners there. But we assume that miners will run similar software to that on the mainnet and make sensible decisions regarding the fees they put in a block, so higher fees should make the transactions mined faster yes.
Comment: One thing about testnet, though, is it's much easier for one miner or group to effectively take over, either for testing or maliciously.  They might be running non-standard software and decline to mine regular people's transactions.  Likewise, it's also easier for someone to flood the network with high-fee transactions.


Cat pulls his claws off while being transported

Question: My cat hates the car and his travel box (plastic with wire mesh). He claws at the boxes air vents / grill and goes a bit crazy when we drive, which leads to pulled off claw sheaths and a bit of bleeding. How do I stop him from doing this? Is there any solution other than sedating him?
Comment: Kitten mittens?
Comment: Does this only happen when you're driving, or does it happen whenever he's confined to the carrier? Also, when you put him in the carrier, does he seem frightened?
Comment: Only when I'm driving. When I put him in he seems distressed, when I drive he seems to be genuinely frightened
Answer: I would suggest cutting the cat's claws immediately before transporting him.  Make sure to use proper clippers designed for use on cats.  Another suggestion is to get a different cat carrier, one that the cat is less likely to get their claws caught on.  They make tote bag type carriers that are constructed from heavy cloth materials like nylon rather than hard plastics, which may work better for him.  You could also try covering particular problem areas with a towel or something, as long as it doesn't block all the carrier's ventilation.  Cloth is of course porous, so air could get through, but it might become too hot if all openings are completely covered.
Comment: I always cover the carrier with a towel.
Answer: Have you tried using a product called Feliway? It is plugged into the wall and is used for stressful situations. They also have a spray and suggest spraying the carrier a few minutes before you travel. You can read more about it both on the Feliway site and Amazon. It's on cheap.


Can a tourist pre-book and travel with Indre Namdal Trafikk bus line 17-599 Namsskogan – Smalåsen?

Question: According to various travel planners, including Entur, Opentripplanner and Transitfeeds, there is a 03:28 bus from Namsskogan stasjon to Smalåsen, presumably timed to correspond with the arrival of the train from Trondheim.  I can find very little other information on this bus, other than that it is a bestillingsrute, driving only on request.  It is apparently operated by Indre Namdal Trafikk A/S who appear to have no internet presence.  I found a 2012/2013 timetable (6 years old) that does not mention this bus line to Smalåsen, but it does explain that Bestillingstransport består av tilbringertransport og servicetransport. and Tilbringertransport gjelder alle som bor eller
oppholder seg i nevnte kommuner og har lengre avstand til buss og togstopp enn 2 km. and Servicetransport er for deg som trenger transport til
butikk, bank, postkontor eller andre service kontorer.
Transporten kjøres på faste dager til faste tider. which appears to mean it's a pre-order bus (no surprise there) and/or only for residents or for transport to shop, bank, post office, etc (and then only twice a week).  Neither of those apply to me and according to the aforementioned sources the 17-599 appears to run every weekday.  Can I, as a tourist, pre-order transport on this bus 17-599 to travel to Smalåsen (gateway to Børgefjell National Park, in case anyone wonders why) in connection with an arriving train?
Comment: Just as a comment, it is almost as close to the national park to just stay on the train until **Majavatn** and then walk directly from there into the park. There is a trail called "Jengelvegen" - which I never knew had a name, that proceeds directly into the national park. I haven't walked all the way from there myself, but it looks spectacular on the map. Just food for thought!
Comment: @StianYttervik The night train does not call at Majavatn (assuming | in timetable means no stop; see *train from Trondheim* link).  It calls at Trong, Namsskogan (request stop), then Trofors.  However, on my way back I am likely to board the train in Majavatn to catch my flight back from Værnes in the evening.  Thanks for the Jengelvegen pointer though, I should check that out!
Comment: Ah, then I understand. (I think it would be easier to go to Majavatn from Namsskogan though, that is directly on the E6, the main road going north/south - hitch-hiking or by bus). Of course, if you arrive at night you might very well be better off with your original suggestion. I won't try to compel you to change plan, sounds like you have been thorough. Have a good hike!
Answer: I just asked the customer service and there is a bus service operating on demand between Namsskogan station and Smalåsen for every train stopping in Namsskogan.
The service must be ordered in advance, either by contacting customer service by phone +4707417 or +4775771861 (the short service number is not necessarily reachable from outside Norway).
The price for an adult ticket is 60 NOK if paid cash, or 37 NOK if paid with T:kort (an electronic prepaid travel card) or with the Mobilett app.
Comment: About +47 07417: I don't think you can call Norwegian 5-digit phone numbers that easily from abroad. I have tried in the past, and it has not worked. Things may have changed, but I would go for the other phone number to be safe. Also, please use spaces in phone numbers to make them easier to read. The Norwegian standard for 8-digit phone numbers (excluding those beginning with 4 or 9) would make it +47 75 51 18 61.
Comment: @gerrit I didn't ask, but I would very much expect the bus to wait if the train is delayed. Even with 'regular', scheduled transport in Norway, connecting services often wait for delayed incoming transport, at least if the departures are very infrequent.
Comment: Takk!  Being on-demand presumably implies it waits for a delayed train, too.
Comment: @Arthur As I already wrote, it depends on where you are calling from. I am abroad and can call the number from my cell phone, but not from my fixed line. The problem is usually not the number length, but that the five digit numbers are charged at a higher rate, which a foreign phone operator may not be willing to cover.  For the same reason, you may also not be able to call 8-digit numbers starting with 810 or 815 from abroad, as these are also charged at a higher rate.
Comment: @Tor-EinarJarnbjo I would guess that that also goes for 829-numbers. But yes, I was a bit quick there. As we say here in Norway: sorry.
Comment: Looks like the linked website is down.
Comment: @gerrit The web site is moved to a new URL and there does not seem to be possible to contact customer service by chat anymore. I have updated the answer.


"Tu es Français, pourquoi besoin d'un cours?"

Question: Could you please explain the meaning of the phrase "Tu es Français, pourquoi besoin d'un cours?" to me?
I was told that this has a certain zen koan-like quality, and my French isn't enough to understand all the nuances.
Thanks in advance!
Answer: You are French, why do you need a lesson ?
By the way, it is not strictly french. I mean every french would understand what you say, but you should say something like : "Tu es français, pourquoi as-tu besoin d'un cours ?"
Answer: The "zen koan" sense you're searching for may suit a native french speaker.
In a situation where a teacher would ironically tell him to skip lessons to make him learn the difference between knowing and applying rules and practice habits
BTW : I agree both translation and grammatical improve from vekah
Answer: This is a complement on the "zen koan-like quality" of the quote as opposed to its meaning. I was curious since I wasn't familiar with the term koan so I had to check(in French):

Un kōan [...] ou koan est une courte phrase ou une brève anecdote
  absurde, énigmatique ou paradoxale, ne sollicitant pas la logique
  ordinaire,  utilisée dans certaines écoles du bouddhisme chan[...]
Exemples de kōan
  Un disciple ayant demandé au maître Joshu : « Un chien a-t-il la
  nature de Bouddha ? » Maître Joshu répondit : « Mu ! » – Mu ! est le
  wato de ce kōan.
[ Wikipedia ]

This is used as a meditative device. It is rooted in Buddhism, its concepts and the languages involved - it does not appear to be mainly a stylistic device imho - and the examples provided use proper French throughout. My reasoning is to the effect that since I believe the sentence you present feels broken(even somewhat derisive), and certainly not idiomatic, stylish or evocative - once again imho - therefore the koan-like quality someone might have referred to must have been about the meaning itself.1

1. Surely there are challenges with translating such material. Outside of the religious sphere, this is somewhat akin to "proverbes" and "maximes", which may provide insight into "coining" something more idiomatic than what you have. Otherwise standard French along the lines of what other answers suggested should do:

Langue maternelle, dispense du cours (?)
Pourquoi un cours si c'est ta langue maternelle ?
Answer: The possible grammar issues in the original "Tu es Français, pourquoi besoin d'un cours?" could perhaps also be addressed, if absolutely necessary, by simply giving "besoin" a definite article (and maybe by adding "donc"):

Tu es Français, [donc] pourquoi [le] besoin d'un cours?

The literal translation of this variation would be more like

You are French, [so] why the need for a lesson?

Although this version means essentially the same thing as vekah's good translation, there might be just enough of a difference (by depersonalizing/generalizing the "need") to help discover additional koan-like senses/qualities beyond the one already astutely discovered and described by ry81.
Regardless of the accuracy of and possible nuance in my alternate variation and its translation, one additional koan-like sense that comes to my mind (based on my admittedly very weak understanding of Zen and koan) is that this phrase was possibly designed to be studied and analyzed with the goal of helping us reduce our dependence on reason and logic by making us question (and hopefully resist) the tendency to naively jump to seemingly logical conclusions based on stereotypes or other faulty/premature assumptions.