Does this carbon fork have a crack in it that would make you replace it?

Question:
Hello, I dropped the bike from standing and also had a front end collision later. The damage is from dropping the bike from standing because I can see the crack in a much older photo from after the collision. It has not changed much. However, I get worried it is suddenly going to bust on me and I am not very experienced with carbon fiber. Thanks. A bike shop has looked at it and ok'd it, but I am still concerned when going down hills.
Comment: It is so funny that the damage is right next to the label urging you to watch for damage! Reminds me of the "No moleste los signalos" signs in Baja California that had been clearly shot at.
Comment: Would a bicycle manufacturer ship product that a fall from a stand would cause structural failure and instant death to its riders?  Apart from the bad press, imagine the class action law suits. Any guesses how many bikes fall on the ground each day?
Comment: Unless the crack is clearly visible on the outside, it's hard to tell if there's one without an ultrasound scan. I very much doubt the bike shop had an US setup.
Comment: Looks like it's just paint damage and it doesn't extend to the underlying carbon fibers. I'd remove the sticker to make sure there is no crack below it. Generally this shouldn't be a sensitive/weak area.
Answer: What is visible in the photo is a paint scratch. Letting the bike simply fall over will not structurally damage carbon fiber composite. People seem to think CFC is fragile but it's really quite robust.
The fact that you had a collision is much more worrying. How hard? At what angle?
Hard, head-on collisions can certainly damage the frame or fork. The stresses are higher in the head tube or steerer area as the fork acts like a lever. Often damage to the head tube can occur but the fork is un- (or less) damaged.
Answer: It looks like just a paint scrape to me. You should be ok. That said, some stranger over the Internet can't make this judgment call for you - do you feel secure riding it?
Answer: Strangers on the internet, no matter how knowledgeable or well intentioned, will not be able to diagnose internal damage to any part, no matter what it's made of.
Your local bike shop may be able to diagnose it.
For real confidence, find a local frame builder, preferably one who works in carbon fiber and pay to have it inspected. Yes, pay. He's a professional and makes her living this way, and you want quality advice, since it's your neck on the line. The advice in this answer I wrote a while ago, though addressing a steel frame and head-tube damage, applies equally to your potential fork damage.
See also this and this.
No, I'm not a frame builder, but I did know one when I was a kid. He spent many years in school and many, many years perfecting his craft. He took immense pride in his work and letting something out of his shop that he felt was dangerous was something he would not do. After finding that same attitude and level of pride with the builder who examined my frame after my wreck in college, I can't imagine a single frame builder who would do different.
Comment: My objection to this answer is that most frame builders will work with metal, and most of those will tend to just buy carbon forks from established vendors. Frame builders would generally lack imaging equipment designed for carbon (e.g. ultrasonic), so the answer you get might be no better than the answer at a bike store. There are some carbon builders who also do carbon repair (in my city, Appleman Bicycles, or Calfee more generally), as well as some people specializing in carbon repair (e.g. Ruckus Composites).
Comment: Fair point, @WeiwenNg. However, I _did_ specify "preferably one who works in carbon fiber". That may be more difficult to find.


XAMPP terminating worker thread 0

Question: Am running PHP applications using XAMPP server in Windows XP. It was working fine just yesterday, but suddenly it started showing the error: "Terminating worker thread 0 and Terminating worker thread 1". Does anybody know what went wrong? Can you suggest the steps I have to do to fix it?
My cmd prompt is also disappearing when I open it.
Thanks in advance.
Answer: It means you have another web server open....
In my case when I faced that issue, I had the Skype opened using port 80.
To solve this issue, you can try closing Skype and try or go to Skype settings, connection, and disable the checkbox that says: "Use port 80 and 443 as an alternatives for incoming connections"  See this thread: http://www.mydigitallife.info/2008/12/03/disable-skype-from-using-opening-and-listening-on-port-80-and-443-on-local-computer/
Answer: Click the button on the xampp control panel "check ports",
this will show you whats running through port 80, the same port that apache uses by default. I had Skype running through port 80 as soon as I quite Skype apache ran normally.
Thanks
Comment: I see Port80 is process :system, and I don't open skype!! how to solve this??
Answer: Find this file in your apache conf folder : httpd-vhosts
Check this :
<code><VirtualHost *:80>
ServerName localhost
DocumentRoot "C:/xampp/htdocs"
<Directory "C:/xampp/htdocs">
    Allowoverride All
    order deny,allow
    allow from all
</Directory>
</code>

maybe you have wrong code here ;) This is corect code in my file

XAMPP terminating worker thread 0


Can I bring a suitcase aboard the riverboat Koln-Dusseldorfer (K-D) Line, traveling from St. Goare to Mainz, Germany?

Question: I want to experience traveling up the Rhine River in Germany but do not want to do a reverse trip in order to get my luggage. Can I take my luggage aboard The Koln-Dusseldorfer (K-D) Line?
Answer: According to their FAQ (see "Bicycles & Luggage"):

There is no luggage office on board or at the wharf, therefore large baggage cannot be transported (max. hand baggage size). The passenger is responsible for transporting their luggage and other items brought on board to and from the ship. The carrier accepts no liability for luggage and other items brought on board.

However, the german version is muss less specific, saying:

Eine separate Gepäckaufbewahrung ist weder an Bord noch an der Anlegestelle vorhanden, daher sollte kein großes Gepäck (bis max. Handgepäckgröße) mitgeführt werden. Für die Beförderung des Gepäcks und der an Bord gebrachten Gegenstände zum/vom Schiff hat der Fahrgast selbst zu sorgen. Eine Haftung für Gepäck oder an Bord gebrachte Gegenstände wird ausgeschlossen.

with the relevant part saying that no large baggage should be brought aboard. So maybe you can take it with you, but I wouldn't bet on it.
If you want to be sure, you should write to them at email@example.com.
Note however, that if they don't allow it, a train trip back will be much shorter than going by boat.
Comment: I think _less restrictive_ is a better way to describe the difference than _less specific_. It is very specific in German. It means _we don't have a place for you to store the luggage and then walk around on the boat. You always have to keep your huge suitcase with you, which is probably inconvenient. And if someone steals your stuff, bad luck. So we suggest you don't bring luggage, but we don't really care._
Comment: @GayotFow: Thanks, I'll try. I agree with you. If it was strict in any way, there would be a better way to phrase it in a formal tone (and I hope, they'd have chosen it then).
Comment: +1, so wonderful to see some expertise on Father Rhine; I do hope you will continue here.  And for me "sollte" is used as a modal in keeping with the formal tone of the advisory, sietzen, and hence relentlessly ambiguous. Thanks again for a great answer.
Comment: @simbabque I guess you're right, but I guess I'm also right. Note the english version is easy to understand for the traveler, because it just means that you have to leave large bags somewhere else, but the german version could mean a.) bring it and we will transport it, but you have to take care of it yourself, or b.) we cannot guarantee that there is enough space, because there might be many passengers.
This, of course, doesn't really help the passenger, so they better ask beforehand to have a definitive answer.


How to quickly setup a developer machine?

Question: I know this can be done and i have seen it done using some front end gui tool (using robocopy internally) I am just not able to lay my hands on this stuff tried google but wasn't able to get to it.
I am about to start a new project and i have finished setting up a desktop with all the tools required on that machine. what i want now is a tool or utility...to which i can say here is one folder , (and some other folders..) take this and prepare some sort of setup program which when run on any machine (winxp sp3) will copy/install all those programs onto that machine.
To add to this, I have the build server virtualized and i am not talking about virtualization and ghost images. i have some software utilities that make a programmers life easier (such as IDE's with varoious plugins (with correct configuration and versions), Small Software tools (tcp monitors), etc.) which I want to add to a developer machine.

Update:
I don't think anyone is reading the question entirely. I said I have seen this thing get done, by some front end gui program which generates a setup program i am not able to find the program which does this and it uses robocopy internally, which you can copy in a redistributable location (pendrive/networkdrive/ftp/http...the list goes on)...upon execution of which that program will copy all the programs and files to the target machine on which this setup is run...and i am not talking about simple file copy...that would be an easy batch/powershell script...i think that can be done very easily...and if nothing comes up i will do exactly that....but robocopy might skip the programs like launchy and shell extensions...

Update:
Ok...I gave it another thought (for now i have done a workaround...)...does anybody know of a program that can generate setup programs like installshield etc...and which come for free...

Update:
The persistent bastard that i am... nullsoft scriptable install system blew my horn. and thanks to that i now have a setup.exe which i can run on any system and make that system feel like home to any good java developer.
Answer: Try http://www.symantec.com/norton/ghost
Comment: but i don't want to install the entire OS Image. the developer machines already have some software...I just want to add some stuff to it.
Answer: I have a couple of different base development environment configurations hosted on virtual machines (Virtual Server 2005). Once I was happy with them I sysprep'd them. Now when I need an environment for a specific project type I clone the VM with the config I require, start it up and and off I go to work. The great thing is that if I wreck the VM all I need to do is start afresh from one of the sysprep images. It's such a timesaver.
Answer: NSIS is the answer to this sort of Magic trick.
Answer: Acronis Trueimage is a good way if you have performance/memory issues for your machine! (if you want a full reinstall).
We use VMWare to supply a full image from the network or from a portable hard disk.
You benefit from the same (custom) host environment which project depending guest changes.
For bigger projects we think about VMWare view, because we have an already delopyed ESX Cluster running.
If you only search for software distribution utilities, you should have a look at Microsoft SMS
Comment: i have the build server virtualized already..and is available via ftp/smb...but these are some programming libraries and utilities (like eclipse with some plugins, launchy, copy path shell extension..etc)which make programmers life easy..i want to create a setup program when run will copy all of thm
Comment: Think about creating development VMs and put the tools into them. Thats the way we handle this issues!
Answer: If you happen to be developing ASP.NET in the Windows environment, the Microsoft Web Platform Installer is a good bet for getting a new workstation up and running quickly.
Answer: Maybe you are talking about the Robocopy GUI. I haven't tried it myself, so I don't know if it's what you're looking for.
Otherwise, Ghost should be able to just pick some folders and files and not only complete OS's so that might be a better choice, not sure if you can deploy the software in other directories than the one on the master machine though.
Or, if you actually are going to do it to a lot of machines, then maybe a deployment software like Microsofts SMS would work.
Answer: Using an installer of a virtualization package is the obvious technical answer, but you should also think about some written processes as well.
One of the things that always happens to me, is I keep thinking that "I'm just doing this once, or if I have to do it again, I'll remember what I loaded, where I got it from, and how I configured it."
...and I'm usually wrong. I almost always end up duplicating one environment because I got another machine, or I'm working from another location, or something failed, etc.
So, I strongly recommend keeping a written record, but nothing too sophisticated, at first. Something simple like: name of package, current version, and why you loaded it.
If you start doing something again and again, you might want to start putting down the steps, especially if it is a shared resource. If you need to do it a lot, you might keep all the software images in one place, like a shared folder or a USB flash drive.
(In the brave, new Web 2.0 world, you could use a ticket tracker like Fogbugz online to keep track of this stuff, one ticket per system type...)
The main thing to remember is that, these configurations often take a life of their own, and live far beyond your expectations. You will probably need to support new operating systems, new releases, etc.


Minimum sample size for Spearman's correlation and Kendall's Tau b

Question: I've tried looking for scholarly articles to determine the minimum sample size that is required to perform either the Spearman's correlation and Kendall's Tau b hypothesis tests. However, I can't seem to find any documentation that strongly suggest the minimum sample size one should use. By any chance, would any of you know how many sample size is ideal?
Comment: The minimum possible size is 2 pairs, but it's not very useful at that sample size (since on continuous variates such correlations will always be $\pm 1$). 3 pairs will give 4 different possible correlations for each, and 4 pairs will give 11 and 7 possible values for Spearman and Kendall respectively, in every case assuming no ties. On what basis are you choosing a minimum sample size? Do you want the smallest size that can reach some significance level? Some power for a given alternative? The last question is even less clear, but again, on what basis are you choosing an ideal sample size?
Answer: For the purposes of a hypothesis test, there are two related approaches to finding an optimal sample size that are viable if you're willing to assume bivariate normality.
Power
To estimate minimal sample size at a given confidence level ($1-\alpha$) and power ($1-\beta$), we can use a modification of the equation for calculating the power of a Pearson correlation ($r$):
$$n=3+\bigg(\frac{z_{\alpha/2}+z_{\beta}}{z(r_{1})-z(r_{0})}\bigg)^2$$
Where the numerator represents the boundaries of a normal distribution at a specified $\alpha$ and $\beta$, respectively. The denominator takes the Fisher Z transformed estimated values of the expected ($r_1$) and null ($r_0$) correlation (Bonett, 2016). For a null hypothesis of no correlation $r_0 = 0$, though this need not be the case as the formula accommodates different values for a more specific null.
For the Kendall coefficient ($\tau$), we use a monotonic transform as per Fieller, Hartley, & Pearson (1957) to modify the formula slightly and solve for n:
$$n=4+.437\bigg(\frac{z_{\alpha/2}+z_{\beta}}{z(\tau_{b1})-z(\tau_{b0})}\bigg)^2$$
For the Spearman coefficient ($\rho$), following the transform in Bonett & Wright (2000), the formula is:
$$n=3+\bigg(1+\frac{\rho^2_{s1}}{2}\bigg)\bigg(\frac{z_{\alpha/2}+z_{\beta}}{z(\rho_{s1})-z(\rho_{s0})}\bigg)^2$$
The minimum sample size will therefore depend upon the expected level of $\tau$ or $\rho$ to reject the null, at a specified confidence level and power. More details on power can be found in Looney (2018).
Precision
Say you have a reasonable idea what range of values your $\tau$ or $\rho$ 'should' be in. In this case, you may want to estimate the sample size to achieve a particular confidence interval (CI) width (e.g. $\rho=.3\pm.1$) for precision. Provided the CI width ($w$) specified does not cross zero, you've effectively guaranteed sufficient power for a standard null hypothesis significance test as well.
Bonett & Wright (2000) established a two-step method to achieve this, again using a monotonic transform assuming bivariate normality. They provide a handy table of minimum sample sizes required across a range of different correlation values, CI widths, and alphas on page 26. But I'll outline the rough approach below.
First, calculate an initial imprecise approximation of the required sample size ($n_0$) at a given estimate of the Pearson, Spearman, or Kendall correlation (denoted more generally below as $\hat{r}$) and a desired confidence interval width (set at $w$). This given by:
$$n_0 = b+4c^2 (1-\hat{r}^2)^2 \bigg( \frac{z_{\alpha/2}}{w}\bigg)^2$$
Where

$b$ is equal to 3 for the Pearson and Spearman correlations and 4 for the Kendall; and
$c$ is equal to $1$ for the Pearson, $\sqrt{(1+\hat{r}^2)/2}$ for the Spearman, and $\sqrt{.437}$ for the Kendall.

Second, use a Fisher Z type transform to find the confidence intervals of $\hat{r}$ given the initial sample size approximation of $n_0$
$$\text{Lower Limit}=\frac{[\exp(2L_1)-1]}{[\exp(2L_1)+1]}$$
$$\text{Upper Limit}=\frac{[\exp(2L_2)-1]}{[\exp(2L_2)+1]}$$
Where
$$L_1=.5[\ln(1+\hat{r})-\ln(1-\hat{r})]-\frac{c(z_{\alpha/2})}{\sqrt{n_0-b}}$$
$$L_2=.5[\ln(1+\hat{r})-\ln(1-\hat{r})]+\frac{c(z_{\alpha/2})}{\sqrt{n_0-b}}$$
The idea is to now subtract the lower limit from the upper limit to find the estimated width ($w_0$) of the confidence interval of $\hat{r}$ given the initial sample size estimate $n_0$. This $n_0$ sample size will typically not be exactly correct, but we can use this information to adjust to find a better estimate by:
$$n = (n_0-b)\bigg(\frac{w_0}{w}\bigg)^2+b$$
Note however that this estimate may perform poorly at the upper ends of the correlation (say, $\hat{r}>.8$). In this case, a more conservative estimate is given in Doug Bonett's lecture notes as:
$$n = n_0\bigg(\frac{w_0^2}{w^2}\bigg)$$
In practice, I've found this gives approximately the same values at the lower ends of possible $\hat{r}$ values too, so maybe just default to that.
Problems
As stated a couple of times here - the critical assumption to all of these theoretical estimates is that both variables are normally distributed. This may be problematic. Frequently researchers will want to use $\tau$ and $\rho$ specifically because their variables are not normally distributed (but are instead skewed, ordinal, etc). The extent to which these methods will work in those circumstances is uncertain. Simulating data that resemble your own to empirically estimate power or precision across a range of possible sample sizes may be a reasonable work-around, but I'm not sure.

References
Bonett, D.G. (2016).Sample Size Planning for Behavioral Science Research.  Retrieved from http://people.ucsc.edu/~dgbonett/sample.html.
Bonett, D. G., & Wright, T. A. (2000). Sample size requirements for estimating Pearson, Kendall and Spearman correlations. Psychometrika, 65(1), 23-28.
Fieller, E. C., Hartley, H. O., & Pearson, E. S. (1957). Tests for rank correlation coefficients. I. Biometrika, 44(3/4), 470-481.
Looney, S. W. (2018). Practical Issues in Sample Size Determination for Correlation Coefficient Inference. SM Journal of Biometrics & Biostatistics, 3(1), 1027.
Comment: Can you elaborate a little bit on the tau b1 and tau b0 when determining the sample size for the Kendall rank in the Power section. What are tau b1 and tau b0. Thank you very much
Comment: Excellent answer.  Precision is usually the more appropriate criterion.  See also the `plotCorrPrecision` function in the R `Hmisc` package.
Comment: @KhoiBoo Certainly. The $\tau_{b1}$ represents the expected Kendall's Tau-b correlation, and $\tau_{b0}$ represents the null Tau-b correlation. Often $\tau_{b0}$ is simply zero, corresponding to a null hypothesis of no correlation, but you can set this differently if desired. The value of $\tau_{b1}$ depends upon your research question and is up to you.


What happens to surface tension upon increasing surface area

Question: Pretty self explanatory title. But I just read in a book that the surface tension remains same even if the surface area is increased. What could be a possible explanation for that?
Comment: Note that this is in the absence (or alternatively with a saturating bulk density) of surfactants, else there'll be a dependence.
Answer: The surface tension is a consequence of the interfacial energy. If you consider some area of the liquid surface $A$ then there is an interfacial energy proportional to the area:
$$ E = kA $$
for some constant $k$ that is dependent on the forces between the atoms/molecules in the liquid. If we increase the area of the liquid surface we increase its energy, and that means we have to do work on it. If we do work we must have been exerting a force on the boundaries of the surface, and the force per unit length of the boundary is what we call the surface tension.
The interfacial energy is a consequence of the atomic/molecular interactions in the liquid so the interfacial energy per unit area is a constant and not dependent on the total area. That means the surface tension is also dependent only on the interactions within the liquid and not on the total area.
Answer: In liquids, when the surface area is increased, molecules are allowed to move from the bulk phase to the interface. As a result, the number of molecules per unit area (i.e. the distance between the molecules at the interface) remains the same. Therefore, the surface tension does not change.
In solids, I am not sure about the change in the surface tension. I read in an article that the surface tension of a solid still remains the same and the solid molecules can travel to the interface. However, since it is difficult for them to travel, you need to apply a much larger force to bring the molecules to the interface and increase the surface area of a solid.
Just imagine that you want to stretch a copper wire. Isn't it easier to do so when the wire is hot? This is because

The mobility of the molecules is better at high temperatures so that they can go to the interface more easily, and

The surface tension of the solid is lower at higher temperatures so that the traveling molecules can be accommodated in the interface more easily.


How to use multiplayer over Bluetooth

Question: I have seen videos that say that you can use other apps that have a Bluetooth connection to play, but I guess it doesn't work on iOS 9. Is there any way to use local multiplayer over Bluetooth?
Answer: 2 players max per server.

Get any game which supports Bluetooth multiplayer eg Lightbike 2 (because it holds 4 people).
Enable Bluetooth in Settings.
Host room and wait people to join.
After clicking home button you'll see at the top that people are paired.
Go to MCPE.
Launch server.
Wait a person to join.

See This for more

How to use multiplayer over Bluetooth


How do I open images in Preview at full size?

Question: Is there a way I can get Preview to open images in Actual Size by default and not have it fit to screen? I vaguely remember this as an option in previous versions of Preview, but am unable to find anything in the current version. System is 10.7.3 with Preview Version 5.5.1 (719.11).
Comment: I think the most bothersome issue is when you Command + 0 (zero) and turn to the next page, it reverts to Fit to Screen and then you have to change it again; very annoying for reading many pages.
Answer: View>Actual Size or Command + 0 (zero):
Comment: Thanks, but I know how to do that. I am asking about having it default to opening at full size. Not opening, then changing size.


What is the modern equivalent of Soviet tire size 65-405 (2.50-16)?

Question: The title question says it all. My Goggle-Fu isn't strong enough to find any conversion charts. The only size-related markings on the current tires are 65-405 (2.50-16). I believe they are motorcycle or motorcycle-sidecar tires with a tube.
Answer: From what I'm seeing, the 2.50-16 is the current size. Doesn't look like there's a large selection out there but you can find them. They are shown as a front tire. A Google search for "motorcycle tire 2.50-16" gave me a pretty good list of things.
EDIT: To clarify, the 2.50-16 is 2.5" x 16". This is imperial sizing for the tire. Also, if your rim requires a tube for the tire, you can get a tubeless tire and still put a tube in it to keep the air in. Either kind of tire will work.
Comment: OK, I finally found them in local shops too. I think it was the rarity that threw me off, because I tried searching for that "2.50-16" and came up empty handed. Thanks!
Comment: A local shop just replied to me that they don't have the 16x2.5 that I ordered 3 weeks ago, but that they do have 16x1,75-2,1. It's close... do you think it would still work?
Comment: @Vilx- That'd be 30% skinnier tires. I mean, they'll fit, but that's a LOT smaller than stock. I wouldn't run them, but that's up to you.
Comment: OK, I'll keep looking. Thanks!


how to find the .class file after running a .java project on vscode for macOS?

Question: I'm trying to find the .class file after running a java project in VScode on macOS, I searched Google but there is only a path for Windows OS. Can anyone help to figure out the .class file?
This is the java project's name: testSearch.java

I want to find the testSearch.class file after running.
Answer: Explanation
By default, VSCode outputs '.class' files into different locations depending on the type of file you're working with:-

If you run a single '.java' file, it'll output the '.class' file into a path that looks like this: /private/var/folders/ys/rgjr_wyd0d715dz546hydfrr0000gn/T/vscodesws_6d2aa/jdt_ws/jdt.ls-java-project/bin

If you open a folder that contains '.java' files and run them, the '.class' files will be inside of a path that looks like this: /Users/YourUserNameHere/Library/Application Support/Code/User/workspaceStorage/e358195aec7543686cb2440051c91f82/redhat.java/jdt_ws/SplayTree Project_d551e7d6/bin

Solutions

To find the output path for your own project, just look for it inside VSCode's terminal after running.

To change the default output directory for compiled '.class' files:
Go to VSCode settings -> Search for "java project output path" -> Click on "Edit in settings.json" -> Add the desired path inside the quotation marks (Note: this will only work with Workspace projects. It won't work with Maven/Gradle).


Why Seven Principal Tones?

Question: Why are there seven principal tones (A-G)? Just tradition? In the same vein, why are various sounds (of differing pitches) said to represent the same principal tone?
Comment: Can you please elaborate? Your second sentence is unclear, and I don't see how the first is not answered by many questions [already asked](http://music.stackexchange.com/questions/8173/the-major-scale-why-and-how?rq=1) on this site.
Comment: Second question might be about octaves, why A1 and A4 are both A for example. They are all multiples of the lowest frequency: A2 is 110Hz, A3 is 220Hz, and A4 is 440Hz.
Answer: Why are there seven principal notes?
The short answer is: We don't know. Some music traditions (Western, Middle Eastern, Indian...) prefer heptatonic (seven-note) scales. We are not sure if these traditions are connected or not. There are attempts to explain the major scale based on harmonics but they can't explain other heptatonic scales used by these traditions.
But heptatonic scales are in no way universal. Other musical traditions (African, Chinese, Japanese...) prefer pentatonic (five-note) scales. We also don't know why pentatonic scales are so widespread.

The second part of your question is not very clear.
If you're asking "Why C# ≠ Db?" take a look here. It's basically about the context.
If you're asking about why 220 Hz and 440 Hz (notes one octave apart) have the same name (octave equivalence), it appears to be related to the neurology of hearing.
If you're asking about why 440 Hz and 420 Hz are both called A in different tuning standards, it's mostly about tradition and standardization.
Answer: There are a couple of ways to look at it. Usually people look at the theoretical aspects, and talk about how its constructed from the overtone series. There is some truth to this. Once polyphony was invented (multiple voices sounding different parts at once) it was important that the notes we had were tuned largely to consonant intervals, which have a basis in the physics of acoustics, and the overtone series.
However, there is also the historical aspect to your question (which you allude to by asking if it is tradition). Historically, early western music was patterned after ancient Greek music. The ancient Greeks knew about ratios of string lengths, and as such, were well-familiar with the consonant intervals known as the octave, perfect fifth, and perfect fourth. They built scales using a system of two adjoining "tetrachords". A tetrachord is a four-note descending scale fragment in which the outer two notes are fixed an interval of a fourth apart, and the inner two notes could be tuned in various relations to one another (called the tetrachord's "genus"). Tetrchord-based systems were used to tune the strings of their lyres.
There were three genera of tetrachords (diatonic, chromatic, and enharmonic). The enharmonic genus used what we would call microtonal intervals, and the choromatic genus used two adjacent semitones; both of them then had a large gap in order to reach the fourth note. However, it was the diatonic genus (consisting of two steps and a half step) that would later be adopted into Western music. This was considered the most natural genus, as it filled the fourth relatively evenly, without as much contrast between tiny intervals and large intervals.
When two tetrachords were combined, it fell just short of an octave, by one step. This step could either be added to the bottom of the scale, or placed in between the two tetrachords (so the second one began a step lower than where the previous one ended).
Ultimately, the Greek developed a two-octave scale system consisting of four tetrachords called the Greater Perfect System. It roughly began at what we would call the A above middle C, and descended two octaves. Using the diatonic genus (a descending pattern of WWH), the notes would approximately correspond to (I'll surround tetrachords in parenthesis):
(a g f (e) d c B) (A G F (E) D C B,) A,
Answer: Here is a conjecture: It's about what is considered the smallest useful interval.
In Pythagorean tuning, intervals are built up from octaves and fifths.  Suppose we start from C 256 (and C 512) and go up some fifths, wrapping to the first octave where necessary.

G 384 introduces two intervals, 2:3 (702 cents) and 3:4 (498 cents).
D 288 — C:D = 8:9 (204 cents) and D:G = 3:4.
A 432 — G:A = 8:9 and A:C = 27:32 (294 cents).
E 324 — D:E = 8:9 and E:G = 27:32.
B 486 — A:B = 8:9 and B:C = 243:256 (90 cents).

Notice that A and E introduce no interval smaller than the smallest among C:D:G:C, but B:C is less than half that width, so B might be considered redundant.  This could be part of why pentatonic scales are so common.  Interestingly, if you keep this up, you get 12 notes before the next smaller interval (24 cents) appears.
Later, the Meantone scale made the fifths slightly flat, to shift the major third C:E from 64:81 to the more harmonious 4:5 (64:80).  That gives a slightly different picture.

With 2 notes per octave, the smallest interval is 503 cents.
With 3~5 notes, 193 cents.
With 6~7 notes, 117 cents.
With 8~12 notes, 76 cents.
With 13~19 notes, 41 cents.

This time, the interval introduced by the sixth note (B) is not so small; but that introduced by the eighth (C♯) is even smaller than the one rejected by the pentatonic scale above.  Hence, seven notes may be a natural cutoff in a scale with just thirds.
I know this is, at best, only one aspect of a more complex picture.

Why Seven Principal Tones?


Is there any review books for beginners in philosophy?

Question: I would like to gain some knowledge of the most famous philosophers' ideas. I have only read Plato's dialogues and have some general idea of Western philosophical tradition thanks to youtube lectures on various philosophers. What should I do next? I have tried to read Aristotle's "Metaphysics" but it was too hard to understand. Should I still continue reading original texts or are there any review books that could help me? (I have tried Cambridge Companion series and Bertrand Russell's "History of Western Philosophy" but none of them turned out what I was looking for).
Comment: Does this answer your question? [How to get started with philosophy without getting overwhelmed quickly?](https://philosophy.stackexchange.com/questions/2115/how-to-get-started-with-philosophy-without-getting-overwhelmed-quickly)
Comment: See [this post](https://philosophy.stackexchange.com/questions/4248/what-are-some-good-introductions-to-philosophy)
Comment: What do you mean with "review" in your question? Based on your QA description it seems you want to know something else then your question (in title) asks for. Making your question hard to answer correctly. I think what you're essentially asking for is a duplicate of this: https://philosophy.stackexchange.com/questions/2115/how-to-get-started-with-philosophy-without-getting-overwhelmed-quickly
Comment: By "review books" I meant some kind of material (like Cambridge companion series) that would help me understand philosophical texts and make complex subjects a bit clear.
Comment: "like Cambridge companion series" There are many: Aristotle, Plato, Descartes, Kant,... Why not use them?
Comment: We recently had the question  'learning philosophy without guidance' https://philosophy.stackexchange.com/questions/93941/learning-philosophy-without-guidance/93949#93949 It's really helpful to get background about what kind of thing a thinker or school of thought is doing, before reading original texts. If helps take more in when you then read them
Answer: There are innumerable books of the type you're looking for. The problem is that philosophy really can't be taught neutrally. Each individual philosopher is arguing for their own, radically different ways of looking at the world. So even the process of selecting philosophers to include (or omit), and deciding how to present, interpret or summarize their work is going to be opinionated in ways that end up offering very different views of the discipline of philosophy as a whole. In essence, you simply end up studying the philosophy of the editor.
Given that, you might be best sticking with primary sources, some of which can be surprisingly easy to read directly. Plato's early dialogs and the Meditations of Descartes are two of the most influential works in all of Western philosophy, and they are both very easy and quick to read and understand --at least on a superficial level. Some other influential but accessible philosophical works include Ecclesiastes and the Tao Te Ching.
You can also find encyclopedia-style works with capsule summaries of each philosopher, but the value of those is questionable.
Answer: Four Ages of Understanding: The First Postmodern Survey of Philosophy From Ancient Times to the Turn of the Twenty-first Century by semiotician John N. Deely is very good. It quotes original sources like Plato's Meno and will enable you to appreciate and understand the original writings of Aristotle, Aquinas, et al.
Deely's PhD student Brian Kemple's free Introduction to Philosophical Principles is also very good.


UITableViewCell image load from url

Question: I have a problem with loading an image from an url to display in a table. I currently have the following code to handle the image loading in a class that extends UITableViewCell:
- (void) initWithData:(NSDictionary *) data{

     NSDictionary *images = [data objectForKey:@"images"];
    __block NSString *poster = [images objectForKey:@"poster"];

        dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
        dispatch_async(queue, ^{

            NSURL *posterURL = [[NSURL alloc] initWithString:poster];
            NSData *imageData = [NSData dataWithContentsOfURL:posterURL];

            if (imageData != nil) {
                dispatch_async(dispatch_get_main_queue(), ^{
                    // 4. Set image in cell
                    self.backgroundImage.image = [UIImage imageWithData:imageData];
                    [self setNeedsLayout];
                });
            }
        });

    self.backgroundImage.image = [UIImage imageNamed:@"static"];
}

The initWithData method is called from the ViewController in the tableView:cellForRowAtIndexPath: delegate. Everything works as expected until i scroll. From what i read, the TableView cells are recycled and because the images are being loaded async, i get rows with wrong images. Also, the images are not cached and are loaded again whenever the cell is displayed.
Eg: Scroll to the middle and immediately scroll back up. The first cell will have the image that's corresponding to the middle cell that didn't get to finish loading.
Any help or suggestions? Thank you very much :)
Comment: You can use SDWebImage https://github.com/rs/SDWebImage
Comment: If you want caching of image then best to go with SDWebImageView. Yes this is not the problem. If you don't want to use it, then first check whether Image is downloaded or not, then only allow download request. You current implementation is not doing that.
Comment: Thanks i'll try using SDWebImage. But this might not be the real problem...
Answer: First of all as the comment mentioned, I would definitely recommend using an existing framework/component to do this job.
The best candidates are probably:
https://github.com/rs/SDWebImage
https://github.com/enormego/EGOImageLoading
OR if you also want a general networking library
https://github.com/AFNetworking/AFNetworking
That said, if you still want to try it on your own, you would probably want to implement caching with an NSMutableDictionary using the indexPath as the key, and the image as the value.
Assuming you have an initialized instance variable NSMutableDictionary *imageCache
In your cellForRowAtIndexPath method, before attempting to do any image loading, you would check to see if your cache already has an image for this index by doing something like this
if(! imageCache[indexPath])
{
  // do your web loading here, then once complete you do
  imageCache[indexPath] = // the new loaded image
}
else
{
  self.backgroundImage.image = imageCache[indexPath];
}

Comment: No, it should be an instance variable declared in the containing class and initialized before the table begins loading (so in `init` or `viewDidLoad` or something like that).
Comment: You can modify your `initWithData` method to also pass in the `indexPath` and the `imageCache` and then this will still work as it should. So the method declaration would be `initWithData:indexPath:imageCache:`
Comment: just pass in the pointer as you normally would. it is mutable and can be modified by whatever you're passing it to. So `initWithData:(NSDictionary *)data indexPath:(NSIndexPath *)indexPath imageCache:(NSMutableDictionary *)imageCache`

UITableViewCell image load from url


Does "upgrading" to digital special edition for Hotline Miami 2 give you Jacket in Payday 2

Question: So I already own Hotline Miami 2 but not the "digital special edition". In Payday 2 if you own the digital special edition you get Jacket as a playable character. If I just pay $5 to upgrade to digital special edition will I still get Jacket as a character?
Answer: From Overkills Website:

Upon buying Hotline Miami 2: Wrong Number Digital Special Edition on Steam, you get the following:

Acquired when a player buys the Digital Special Edition of Hotline Miami 2: Wrong Number
Introduces 6 new Hotline Miami masks in PAYDAY 2
Adds 10 gallons of Hype Fuel to the Hype Train event
Introduces Jacket of Hotline Miami fame as a playable character in PAYDAY 2
Introduces an additional mask called "Richard Returns" in PAYDAY 2
Adds the Sociopath perk deck in PAYDAY 2
Adds the Carpenter's Delight hammer melee weapon in PAYDAY 2
Adds Jacket's Piece, a Submachine gun with accompanying weapon modifications in PAYDAY 2

The Payday Wiki also says that:

Requires "Hotline Miami 2: Wrong Number - Digital Special Edition" to be purchased on your Steam account.

Upgrading your copy would mean you have it on your steam account, and should unlock Jacket for you.  I've found nothing saying this doesn't work, and it wouldn't make sense for it not to.


Illustrator: How to scale shapes to exact dimensions including stroke?

Question: Is there a way to scale the combined size of the fill and the stroke to certain dimensions without affecting the thickness of the stroke?
Answer: Subtract the stroke width from your desired measurement.
So 500px - 15px = enlarge to 485px with the 15px stroke, the final dimension would be 500px (assuming stroke is aligned to center).
The bigger issue may be that scaling is always relative and never absolute. You can alter an object's dimensions easily (Via the Transform Panel or Control bar), but you can only scale by percentages.
As @Joojaa points out in comments the value fields will do the math for you. So, you can merely enter 500px-15px in the w field and AI will calculate that for you.
Comment: Thanks a lot, thought about subtracting myself, but it seems to complex for a simple task. But nevertheless, thank you for your answer!
Comment: @Lex, Hard to imagine it being much simpler. You can even do the subtraction directly in the Transform panel.
Comment: @Lex you probably arent aware of this but many design software allow you to type the calculation into the input boxes. It even does unit conversions for you so you can go 10 mm - 0.1inch and it calculates for you. See computers are calculators.
Answer: Actually there is a way to make Illustrator include the stroke in the bounding box.
Open Edit > Preferences > General (Ctrl /Cmd + K) and tick on Use Preview Bounds.
Now the size of the object can be set including the stroke.
But, it seems to behave a bit strangely. If I change the dimensions using the mouse while holding down Shift it seems to constrain proportions like expected, but if I enter a dimension, the object doesn't constrain proportions properly. This seems like a bug or perhaps I misunderstand something.

For that reason I prefer leaving Use Preview Bounds unchecked and subtract the stroke width manually like @Scott suggests.
Funny thing is that InDesign by default includes the stroke width in the bounding box and doesn't seem to have an option to change it. But in InDesign there is no problem with constraining proportions when entering values for the dimensions.
Answer: Well, there's an option you have to check. Go to the Edit > preferences > General or just hit the shortcut, Ctrl + K.
Then find the option which says, Scale Stroke and Effects and just check the box.
Now every time you scale an object, the stroke and the effects will also change with it.
(See the below two images for reference.)
Comment: This has basically already been answered, although you explain in more detail. I don't think this is what the OP means though. But we'll see what the OP says if they ever come back.
Answer: Preferences > General > Uncheck Stroke and Effects
One way is to keep the stroke aligned inside of the object and scale through transform panel.
If align to inside provides a shape that is not required then, it is difficult to create a generic scenario that could be work for anyone, I have two ideas that can be used individually or mixed and match as required.
Manually resize the object considering that the final size of the object depends on the stroke alignment.
1) Aligned Center: Stroke Size would be added.
2) Aligned Inside: Twice the Stroke Size would be reduced.
3) Aligned Outside: Twice the Stroke Size would be added.

Use Path Offet.
1) Scale the Object to the desired size - stroke size.
2) Effects > Path > Offset Path
2) Add the Path Size
3) Object > Expand Appearance.

If none of the above works, then I would need sample files to create a script.
Comment: Why downvotes? Read the Question again and that's a reasonable answer. Did you guys actually try it?
Comment: The OP wants to scale an object to certain dimensions *including* the stroke width. See the OP's drawings. Your solution makes sure the stroke isn't scaled but it doesn't help to get exact dimensions. After scaling the stroke width will make the object larger than what you enter in the transform field.


What are sectional views and cutting plane lines?

Question: I am a student in a Drafting 1 class and we are going over all of the section views (full, half, revolved, offset, etc.) and also all about the cutting planes and different ways for that and how to do them in Autocad. Anyways I'm reading from the book and I still don't understand it very well.  Could someone here explain it well?
Comment: Could you expand on what specific doubts you are having? As-is, this question is far too broad to be answered here.
Comment: @Wasabi According to the title, he's just looking for explanations of the views and lines themselves.
Comment: What about this is too broad @Wasabi ? There are multiple section views he's enquiring about, but none of them are that complex and could be fairly easily summed up.
Comment: @TrevorArchibald, I think the question would be improved if he explains what he means by "don't understand it very well." I personally am unclear as to whether he is asking about how to do them in AutoCAD or about the concepts themselves.
Comment: What is "the book," and if it's just the manual,  why doesn't your class have a basic text on drafting and/or a glossary/cheatsheet with all those terms?
Answer: Imagine you wanted to show a drawing of a car. You can show the exterior features just fine, but how do you show the interior features? If, for instance, you wanted to show where the steering wheel was with respect to the driver's seat, how could you do that?
There are a number of different ways to do it, but the most straightforward is with a section view. In a section view, you take an imaginary saw and cut the object along a section plane. Now you have a cut-open car! Now, if you were to look at the side of the car, the passenger's door, passenger seat, ... the entire passenger's half of the car is gone!
Now all that is left is the driver's side of the car, and in looking at it in profile with the passenger's half removed you can now clearly see where the steering wheel lies with respect to the driver's seat.
I put together a crude drawing for you to follow along with below. Note the arrows on the section view - the dashed line shows the person viewing the drawing where the object was cut, and then the arrows show which half you're going to look at. If the arrows pointed down instead of up then you would be looking at the passenger's half of the (American) car.

Lastly, notice that hatching /////// or \\\ or XXXXXX that exists in the section view. This shows you which surfaces were cut. Surfaces that are not hatched were not cut. So, in the example above, you could infer that the back seat is maybe a bench seat that spans the width of the car, where the driver's seat is a bucket seat that is not attached.
They're kind of awkward to look at in the beginning, but once you get the concept (cut the object open, then look at the cut surface), then it becomes a lot easier. Section views can show lots of things, but internal features that are otherwise hard to display would be the most common reason I would use a section view.


Can I pigtail another 240V circuit from a circuit supplying a double oven

Question: For a total of three units being serviced by a 60 amp breaker.  Right now the double oven is run from 240V, and I need to add a 240V circuit for the microwave oven (there is only a 110V there now)
Comment: Your microwave runs on 240? Also, what's to stop someone from using the oven and the microwave at the same time?
Comment: Also what country?
Comment: Commercial microwave?
Comment: A 240v microwave must be over the pond? If in us it may be possible but we would need the listed values of all 3, 240v devices
Comment: Where are you on this planet?  Can you provide the make and model of all three appliances?
Answer: No. Ovens should be on their own circuit.  While you can put them on the same circuit and only use one at a time, having multiple High Amperage Draw Appliances on a circuit is not a good idea!
Just think about it...cake in one oven turkey in the other, then heating the gravy in the microwave would result in a trip to the circuit breaker panel to reset the breaker.
If the breaker and wiring match Gauge and Amperage(i.e. 12 gauge and 20 Amp Breaker) then having multiple Appliances of 20 Amp is fine....the breaker will do its Job and protect the wiring!  If multiple draws are going on at same time...breaker might trip thereby preventing a house fire!
Always a better idea to have the Appliances on their own circuit...even if it is not required by code.  Especially these days with heater coils in dishwashers to heat and sanitize the dishes.....and large 36 inch double ovens!
Comment: While this is technically an answer, it doesn't really explain why not. Expanding this would help the answer
Comment: This *completely* disregards the *explicit NEC language* permitting multiple cooking appliances on a single circuit -- see NEC 210.19(A)(3) Exception 1 for details, as well as Table 220.55 including the footnotes...


What are the full details of the Kurta Clan's destruction and what was Kurapika's role during it? Was he present?

Question: Kurapika was the only member of the Kurta Clan to survive. How? What happened to him? Did he watch his clan die? I know his past life and motive for getting revenge on the Phantom Troupe is mostly just for the story plot, but I still don't understand the full thing.
Answer: The circumstances of the slaughter of the Kurta clan are described in the special two-chapter volume Kurapika's Memories by Yoshihiro Togashi ( https://hunterxhunter.fandom.com/wiki/Volume_0 ), specifically at the end of part 2.
The clan was slaughtered some time in the 6 weeks following Kurapika's departure (so no, he wasn't there). Details about signs of torture and eyeballs having been removed from the bodies, along with a message left by unnamed culprits, were reported in the news. Unbeknownst to all the members but Kurapika and his late friend Pairo, Kurapika's actions before leaving had prompted information about their otherwise secretive clan to be leaked to a nearby community, presumably allowing what we know is the Phantom Troupe to find them.
Comment: thank you, that helped.


Any keyboard shortcut to trigger DDMS screen capture

Question: Most of the time, when I want to capture screen shot of a debugging app, I will use the following button in DDMS.

However, I was wondering, is there any quick keyboard shortcut to do so, instead of using mouse? This is because in certain situation, I need a screen shot, where the app's UI component is being pressed. I already use up my only mouse to perform the pressed action. Hence, there isn't 2nd mouse for me to press the DDMS capture screen button. :)
I do not want to use Windows OS screen capture function. This is because I need an exact color code used in the app sometimes. Using Windows screen capture will not produce accurate image to represent the color used in the app.
Answer: How to take emulator screenshots using Eclipse?

In DDMS, press Ctrl+S to take a screenshot.


Is there a standard on this site to put proper names in italics?

Question: I've been reading through a few of the questions on The Lord of the Rings and The Hobbit, and in many of them character and place names are rendered in italic type. I've never seen this usage anywhere else, but it's so common here it seems to be some kind of standard.
Comment: Wow, and I thought I was pretty much the only one to do that.
Comment: Its a way to differentiating a quote or film title or Important text from the remaining text. Its more an OP's or editors prefrense rather then standard. Some even use Bold for the same reason too.
Comment: @AnkitSharma, I'm not talking about titles, I'm talking about people's names. It's weird, but strangely common on this site.
Comment: @TRiG *Important text* covers character name too. Oops i also used italic here ;)
Answer: No, its just something that a few users do by their own personal preference.
Comment: It seems very weird, and most distracting, but huh, each to his own, I suppose.
Comment: @TRiG Yet it is much better than either not being able to differetiate movie titles from running text or putting ugly "s in there. Yet I guess my way of using it for every kind of proper name might be a bit overkill. Still I like to recognize proper names easily. But like you said, to each his own and I don't usually change an OP's way of doing it when editing a post (apart from movie titles).
Comment: Italicising names of works is normal, @ChristianRau. Standard practise. Italicising names of people and places within those works is *weird*. (But you're definitely not the only person I've seen doing it.)
Comment: True, but you also italicise words or names that you would like to emphasize, not just titles


Only one Honeywell Home thermostat visible in Google home integration

Question: We recently installed a split system with 4 indoor units, and added 4 honeywell wifi thermostats for remote temperature control.  I then wanted to connect the thermostats to Google Home app.  but I found out that no matter what I don, only one of the 4 thermostats is visible to Google Home app.  Is there something I can do to make all 4 thermostats visible in the Google Home app?
Comment: Do you need to set the names on the 'stats so they are different?
Comment: The thermostats all have different names.
Answer: Two things happened since I posted the question.

A few months after the post, the thermostats suddenly all started appearing in the integration.
Sadly it turns out that the Honeywell thermostats don't really work: they don't measure the temperature reliably, nor do they control the AC reliably.  Digging a bit deeper found dozens of people complaining of the thermostats not working.

I ended up throwing the Honeywell smart thermostats away and buying Cielo devices instead.  They work much more reliably and predictably. With that, the issue went away.
Comment: Are you sure they were real Honeywell thermostats and not cheap knock offs from China?   I'm intimately familiar with Honeywell thermostats and how they develop and test them...Honeywell doesn't produce garbage.
Comment: Their serial numbers check out and the devices take firmware updates from Honeywell. I think this is about as sure as one can get.


Disfunctioning songs on Apple music

Question: Some songs in apple music can't be played. It is very weird cause in the start I could listen to these songs, and then suddenly they became unable to play. They just turned grey and it isn't possible to play them. It is very frustrating and I know that it hasn't something to do with my internet connection. It is like this at both my macbook and my iPhone. Have anyone else experienced this? And does anyone know if there is a way of fixing it?
Answer: Sometimes songs are removed from Apple Music at the request of the artist/ publisher.
If you do Get Info on a track you have a problem with, go to the File tab and see what it says for iCloud Status.
If it says No Longer Available then it is as I have described above and is shown in the screenshot I have attached.

Disfunctioning songs on Apple music


What are the url parameters naming convention or standards to follow

Question: Are there any naming conventions or standards for Url parameters to be followed. I generally use camel casing like userId or itemNumber. As I am about to start off a new project, I was searching whether there is anything for this, and could not find anything. I am not looking at this from a perspective of language or framework but more as a general web standard.
Comment: The general trend is to remove technology details from the URL such as `.php`. Besides that people come up with all kinds of "semantic" URL structures. It does not matter much.
Answer: I recommend reading Cool URI's Don't Change by Tim Berners-Lee for an insight into this question.  If you're using parameters in your URI, it might be better to rewrite them to reflect what the data actually means.
So instead of having the following:
/index.jsp?isbn=1234567890
/author-details.jsp?isbn=1234567890
/related.jsp?isbn=1234567890

You'd have
/isbn/1234567890/index
/isbn/1234567890/author-details
/isbn/1234567890/related

It creates a more obvious data structure, and means that if you change the platform architecture, your URI's don't change.  Without the above structure,
/index.jsp?isbn=1234567890

becomes
/index.aspx?isbn=1234567890

which means all the links on your site are now broken.
In general, you should only use query strings when the user could reasonably expect the data they're retrieving to be generated, e.g. with a search.  If you're using a query string to retrieve an unchanging resource from a database, then use URL-rewriting.
Comment: This doesn't answer the question at all. The original post was asking if there was a naming convention for query string parameters. As you mentioned yourself, query strings are appropriate when you are searching through or filtering the data (http://stackoverflow.com/a/17999251/1424734), so why the tangent on their proper use?
Comment: Please answer the question on camel case vs hyphenated naming of querystring parameters instead
Answer: Standard for URI are defined by RFC2396.
Anything after the standardized portion of the URL is left to you.
You probably only want to follow a particular convention on your parameters based on the framework you use.
Most of the time you wouldn't even really care because these are not under your control, but when they are, you probably want to at least be consistent and try to generate user-friendly bits:

that are short,
if they are meant to be directly accessible by users, they should be easy to remember,
case-insensitive (may be hard depending on the server OS).
follow some SEO guidelines and best practices, they may help you a lot.

I would say that cleanliness and user-friendliness are laudable goals to strive for when presenting URLs.
StackOverflow does a fairly good job of it.
Comment: @MartijnBurger because a end-user manually entering the URL may not expect that a string be case-sensitive. Principle of Least Surprise and all.
Comment: I agree with you on the style of urls, and avoiding the parameters, i was interested in this style first when i saw Atlassians's Jira and Bamboo have it, made url's look simple. On Apache it can be set up with some rewrite rules. Do you know anything similar for IIS and .NET
Comment: According to [RFC 3986, 22.214.171.124](http://www.ietf.org/rfc/rfc3986.txt): *other generic syntax components are assumed to be case-sensitive*. So why generate case-insensitive bits?
Answer: There are no standards that I'm aware of. Just be mindful of IE's URL length limit of 2,083 characters.
Answer: I use lowercase. Depending on the technology you use, QS is either threated as case-sensitive (eg. PHP) or not (eg. ASP). Using lowercase avoids possible confusion.
Answer: Like the other answers I've not heard about any conventions.
The only "standard" I would adhere to is to use the more search engine friendly practice of using a URL rewriter.
Answer: There are no standards that I know of, and case shouldn't matter.
However within your application (website), you should stick to your own standards. For your own sanity if nothing else.


Why would Capitol protest at all?

Question: Clearly I haven't read the books. People from the Capitol seem to be doing a pretty well living, they even have luxury and stuff. Why would they want to protest against the regime? Or is it only districts 2 to 12 fighting against the dictatorial regimen on the third movie?
Comment: Why do people from first world countries help people from third world countries? "People from the First world seem to be doing a pretty well living"
Comment: Distict 1 isn't the capitol, it's another district. There are districts 1-12
Comment: To find out, you can read the book, or wait until the 3rd movie comes out. Or if you really have no time to read the books, I suggest reading a wiki or just google for the answer. Refer to the "Search, and research" section from this page: http://scifi.stackexchange.com/help/how-to-ask
Comment: @Kevin: You're saying the people of Capitol had "white guilt?" A bunch of them were black!
Answer: By and large the population of the Capitol don't protest against Snow's regime. They've very indoctrinated that the Hunger Games are a vital part of their history and often turn a blind eye to the poverty in some of the outlying districts (it's widely agreed that the situation gets worse as the district numbers increase).
An example of this is at one of the feasts where they provide a drink which makes the consumer sick so they can eat more... a concept Katniss (from District 12) finds astonishing.
However there are sympathisers, people who are willing to go out on a limb for the districts. I don't want to go into too much detail if you've not read the books on who these are but as evidenced by their actions in both Catching Fire and Mockingjay there are indeed people in the Capitol who feel the system has to change.

Why would Capitol protest at all?


Failing to pair Samsung Gear Iconx earbuds with macOS Sierra

Question: I am trying to pair my Samsung Gear Iconx earbuds with my MacBook Pro via the Bluetooth UI. I put the earbuds very close to the MacBook Pro, but it seems the Mac is not able to discover them. Any ideas how I can get them to pair?
Answer: Actually after trial and error I had to press the button on the back of the case for  some time until it starts to light up blue and red thats when it will show up on other devices
Comment: I have not found a way to quickly switch between a phone and the MacBook yet. It seems you would need to newly pair with the respective device on every switch. If anybody has a solution for that, that would be great.
Answer: Apparently those earbuds don't go into discoverable mode unless you take them out of their special case and put them in your ears when the thing they were previously paired to is not around. And then they only stay discoverable for 3 minutes.
So put them in their case, make sure anything they've been paired with before is completely switched off or far far away, then take the earbuds out of the case, put them in your ears, and use macOS's Bluetooth UI to try to discover them.


Texturing a wall with Joint Compound

Question:
How can I fix this problem of the joint compound cracking on me, without starting all over?
I am using a Premixed Ready to use. What am I doing wrong?
Comment: did you moisten the wall before applying?
Comment: **No I did not.If I were to apply a another coat over it that a lot thinner, would that help my problem some? How thin do I need it to be to finish the rest of the wall?**
Answer: It looks like the mix was a bit dry and a heavy knock down, if there is not enough moisture in the mud or the wall was not prepped well this happens. It is hard to tell is this a patch? If doing an entire area after taping and sanding I usually wipe the wall with a damp towel to remove dust, when I have large jobs done my mud slinger says why wast the time just add water (he is way faster than I am and his work looks good) so I would guess your pre mix is a bit dry you might be able to flake it off with a putty knife but it will need to be removed. Pre mix separates when sitting on the shelf so it needs to be mixed in most cases and for texture I usually add a fair amount of water, for heavy knock down about a cup to a box, for spray knockdown 2 or more cups let it sit then knock down. So to get back on track remove the material that is cracking add some water to your mud and give it another try. Texture is a bit of an art and the amount of water varies with the conditions both humidity and temperature.
Comment: **No it is not a patch, I am covering up the walls in my bathroom (not tub) it was painted over wallpaper and looks like crap. I do not know what you mean by throwback. ( Just a House Wife ) The mud is thick. I hate to waste any thing and I would like to find a way to fix instead of tear down. Any suggestions?**
Comment: I never said throwback but if a painted surface it still needs to be clean, I have textured over paint many times but the surface needs to be roughed up a bit and clean. In my opinion a heavy knock down is a mistake in a bathroom because it will have more surface to hold moisture , mold and have many more problems than looking more ugly than the wall paper that is easily removed.
Comment: ** Okay so I was wrong in thinking that buying Semi-Gloss paint that repels against mold and moister was fine for the walls in my bathroom ? Is there another way to texture the walls in the bathroom without starting over and peeling the wallpaper that seems like a lot more work. I would like to do something different and not common. I am sorry it was Kick Back and not throwback. ( LOL)**
Comment: Wet it down and scrape it off. Strip the wallpaper if you can let it dry prime with flat oil based primer  the do your skip coating with mud let dry then paint 2 coats satin or egg shell sheen

Texturing a wall with Joint Compound


I have a Broan-NuTone AER110LK Bathroom Fan with LED Light that I am installing to a single pole switch. Need help with wiring

Question: I have a Broan-NuTone AER110LK Bathroom Fan with LED Light that I am installing to a single pole switch. Not 100% on wiring because instructions only show wiring for a two function switch. Wire from switch is black,white and copper. Wires from bath fan and light are black, green and white.
Answer: Take the black wires from the light and the fan and connect them to the black wire from the switch. Take the white wires from the light and fan and connect them to the white wire from the switch. Take the green wires from the light and fan and connect them to the bare copper wire from the switch.
With this configuration, the light and fan will operate when the switch is turned on. They cannot be operated independently unless you add another switch and add to or replace the existing wire from the switch
Comment: Greatly appreciated
Answer: Since you are controlling all fan functionality with a single switch, you will splice both the light feed and fan feed to the black wire. In your case this will provide voltage to both components when you turn on the switch. (IF you had 2 switches or a dual control switch, the fan black would go to switch black and the light's black would go to the other switch or dual switch red).
Summary:
Splice the 3 white wires together (1 from switch, 1 from light, 1 from fan)
Splice the 3 greens together (switch/feed ground, light ground, fan ground)
Splice the 3 blacks together (switch black, light's black, fan black)


Complete Codes and Kraft Inequality

Question: Li and Vitanyi define a complete code as a uniquely decodable code to which no codeword can be added while keeping it uniquely decodable. They claim that this is easily seen to be equivalent to equality holding in the Kraft inequality. I can see that equality in the Kraft inequality is clearly a necessary condition, and the other direction is obvious to me for prefix codes, but otherwise it does not seem so easy to me.
Comment: It seems like you need McMillan's theorem (which says that the Kraft inequality also holds for uniquely decodable codes; this is why sometimes this is called the Kraft-McMillan inequality instead). Cover and Thomas have a proof of McMillan's theorem, and the [pertinent wikipedia page](https://en.wikipedia.org/wiki/Kraft%E2%80%93McMillan_inequality) also gives most of the same (see the section on "proof of the general case." The only thing they miss is when the input alphabet is infinite, which is not too hard to get from the finite alphabet case by truncating the code and then taking a limit).
Comment: I know that. Perhaps I'm not seeing something, but I still don't see where this gets me. Just because there is "space" for a codeword which does not start the same way as any other codeword doesn't seem to mean you can just add it to the uniquely decodable code.
Answer: A late but detailed answer to your question. In this answer, "code" means
"uniquely decodable code".
Short answer. If you consider only finite codes (prefix or not) or even regular codes, then
equality in the Kraft inequality implies maximality. It is no longer true for non-regular codes, although it holds for a large family of non-regular codes, the thin codes. See details below.
Long answer. This answer is entirely based on [1], the bible on this topic. Let me first slightly modify your terminology. A code is maximal if it is not properly contained in another code. As you will see below, the term complete is used for a related, but different property. However, for finite codes, maximal and complete are two equivalent notions.
Notation. Let $A$ be an alphabet. The length of a word $u$ is denoted by $|u|$. If $a$ is a letter of $A$, the number of occurrences of $a$ in $u$ is denoted by $|u|_a$. Thus $|u| = \sum_{a \in A} |u|_a$.
Definition 1. A Bernoulli distribution on $A^*$ is a monoid morphism $\pi: A^* \to [0,1]$ such that $\sum_{a \in A} \pi(a) = 1$. It is positive if $\pi(a) > 0$ for all $a \in A$. If $A$ is a $k$-letter alphabet, the uniform distribution is defined by $\pi(a) = k^{-1}$ for each letter $a$, and hence by $\pi(x) = k^{-|x|}$ for each word $x$.
The first result is true without any assumption on the code, which can be finite or infinite.
Proposition 1. If $X$ is a code over $A$, then $\pi(X) \leqslant 1$ for every Bernoulli distribution $\pi$ over $A$.
Corollary (Kraft). If $X$ is a code over a $k$-letter alphabet, then
$$
\sum_{x \in X} k^{-|x|} \leqslant 1
$$
The following result gives a first partial answer to your question:
Proposition 2. Let $X$ be a code over $A$. If there exists a positive Bernoulli distribution $\pi$ on $A^*$ such that $\pi(X) = 1$, then $X$ is maximal.
Example 1. Let $\pi:\{a, b\}^* \to \Bbb Z$ be the monoid morphism defined by $\pi(u) = |u|_a - |u|_b$. Then $\pi^{-1}(0)$ is a submonoid of $A^*$. The base of this submonoid is a prefix code denoted by $D$, called the Dyck code. Let $\pi$ is a Bernoulli distribution $\pi$ on $\{a, b\}^*$. Setting $p = \pi(a)$ and $q = \pi(b)$, one can show that $\pi(D) = 1 - |p-q|$. In particular, if $p = q = 1/2$, then $\pi(D) = 1$. It follows from Proposition 2 that $D$ is maximal, but it is interesting to note that $\pi(D) < 1$ for every non-uniform distribution.
A few definitions are required to give a more detailed answer to your question.
Definition. A subset $X$ of $A^*$ is dense if every word of $A^*$ is a factor of some word of $X$. A non-dense set is called thin.
A code $C$ of $A^*$ is complete if $C^*$ is dense, that is, if every word of $A^*$ is a factor of some word of $C^*$.
Thin codes form a rather large class of codes, which includes in particular all regular codes (and hence, all finite ones).
Proposition 3. Every regular code is thin.
The converse is not true. The code $X = \{a^nb^n \mid n > 0\}$ is thin (for example, $ba$ is not a factor of $X$), but is not regular.
The next result summarizes the connections between maximal and complete codes.
Theorem 1.

Every maximal code is complete.
Every thin and complete code is maximal.
A code is complete if and only if it is dense or maximal.

The following theorem shows that, for thin codes, your question admits a positive answer.
Theorem 2. Let $X$ be a thin code. The following conditions are equivalent:

$X$ is a maximal code.
There exists a positive Bernoulli distribution $\pi$ with $\pi(X) = 1$.
For each positive Bernoulli distribution $\pi$, one has $\pi(X) = 1$.
$X$ is complete.

Let me finish with two examples, which explain why it might be difficult to go beyond Theorem 2.
Example 2. The dense code $$\bigcup_{n \geqslant 0}a^nb\{a,b\}^n$$ also satisfies the four conditions of Theorem 2.
Example 3. The Dyck code $D_2$ over two letters is defined as follows.
Let $F_2$ be the free group on two letters $a$ and $b$ and let $\delta: \{ a,b, \bar a, \bar b\} \to F_2$ be the monoid morphism defined by $\delta(a) = a$, $\delta(b) = b$, $\delta(\bar a) = a^{-1}$ and $\delta(\bar b) = b^{-1}$. Then $\delta^{-1}(1)$ is a submonoid of $\{ a,b, \bar a, \bar b\}^*$ whose basis is a prefix code, denoted by $D_2$.
One can show that $D_2$ is a dense maximal code. However, one has $\pi(D) < 1$ for every Bernouilli distribution and in particular $\pi(D) = 1/3$ for the uniform distribution.
[1] J. Berstel, D. Perrin and C. Reutenauer, Codes and automata. Encyclopedia of Mathematics and its Applications, 129. Cambridge University Press, Cambridge, 2010. xiv+619 pp. ISBN: 978-0-521-88831-8

Complete Codes and Kraft Inequality


Nvidia Graphics Card and 4 monitors

Question: Hi I am using a Nvidia Quadro NVs 420 on a HP desktop. When I put the card in I can see the BIOS screen but I do not see anything after that. If I put the card in my Windows XP computer I get all 4 monitors working. How can I get this graphics card to work with my Ubuntu computer. I am using Ubuntu 10.04.3 LTS btw
Answer: I've not configured 4 displays with a single card but some of the things you will need to have would be:

Native nvidia driver.  Preferably the latest which is 290.10
You will need to enable TwinView and you can see the options here: http://us.download.nvidia.com/XFree86/Linux-x86_64/290.10/README/index.html

Normally for Twinview you would set up Metamode for 2 displays, but general I don't see any reason why you wouldn't be able to do the same for 4.
Once Twinview is set up if you are running 2 pair of displays you would also need to enable Xinerama in /etc/X11/xorg.conf
Option Xinerama "on"

Nvidia Graphics Card and 4 monitors


State Prosecutorial Power

Question: According to Article 5 Section 21 of the Texas Constitution & Chapter 20 of the Code of Criminal Procedure says, "a "city attorney" is not a public officer; He is not granted "state prosecutorial power" & there should be no confusion, as for even the legislature CAN NOT delegate them the power, for it's a NON delegable power." Then why is the "city attorney" doing this in our municipal court?
Comment: Doing what in you municipal court?
Answer: The authorities cited mean that the city attorney can't prosecute cases arising under state criminal laws.
Cases in municipal court are prosecuted under municipal ordinances rather than state criminal laws, in the name of the  city, rather than the People of the State of Texas. Therefore, a city attorney may prosecute ordinance violations in municipal court.

State Prosecutorial Power


Replaced car door speaker, question about connecting the wires

Question: I had to cut the wires and connect the copper strands together, I basically just twisted it together and put electrical tape to hold it. My question is that I cut some of the copper strands of wire when trying to peel off the protective rubber on the wire. Will that affect the performance of the speaker and should I open it up and redo it?
Answer: Most of the speaker wires have more strands or bigger wire diameter than it requires.
But sometimes there is cheaper speaker wire with less strand than it should be so when you cut let's say 3 strands of it, it could make a difference.
Redo the process with the better and more precise procedure is better than you left at it and still thinking it could be better :)
If you think the speaker wire diameter is too small, you could replace the wire with a bigger gauge. (i mean bigger diameter because bigger gauge = less diameter)
For calculation and standard size of speaker wire / watt you can check in this link:

Soundcertified.com
crutchfield.com

:)
Comment: Replacing the existing wire with one of a larger diameter tends to make it less flexible, and given it is in the car door then it will break sooner due to the repeated opening / closing of the door.
Comment: if it has fewer strands then yes it will less flexible. and again like i said : "If you think the speaker wire diameter is too small". and last i stated the calculation link for speaker wire. so he can calculate himself.
Answer: I've made that mistake countless times over 35 years and never had it affect electrical conductivity.  You'd have to cut away like more than half the strands before you'd have a problem, or if the speaker is very powerful and draws high amperage.
What is much more of a concern is the use of electrical tape alone.  The tape tends to unravel when wrapped around a thin wire, unless you melt the tape a little with a cigarette lighter and squeeze it.  I have had wires jiggle themselves loose due to vibration inside the tape, causing tiny amounts of arcing and poor performance.  I've also had problems with corrosion in dry twists, especially if the wire is copper.
Next time, use insulated wire connectors that you crimp with pliers.


How to write recursive formula as explicit (specifically, exponential)?

Question: I recall learning in school how to convert arithmetic and geometric sequence formulas between recursive and explicit, but I don't remember learning a systematic method to approach it. For example, let $a_n=2a_{n-1}+2$ where $a_0=5$. How would I convert this to an explicit form defined in terms of $n$? Beyond this specific example, is there a generalized method to do so?
Answer: There is a systematic way of solving something like $a_n=2a_{n-1}+2a_{n-2}$, which is called a linear recurrence relation. For example this pdf shows you how to do it.
But for your specific example you have a constant $2$, so it's not a linear recurrence. However you can rewrite it as $a_n+2=2(a_{n-1}+2),a_0+2=7$ where it's obvious that $a_n+2=7\cdot 2^n$ so $a_n=7\cdot 2^n-2$.
For a completely general recurrence there isn't really a systematic way to convert it to a formula, but you can always try tricks like the above (linear recurrence, substitution) to see if they work.
Answer: It's equivalent to $\left(~\mbox{with}\ a_{0} = 5~\right)$:
\begin{align}
a_{n} + 2 & = 2\left(a_{n - 1} + 2\right) = 2^{2}\left(a_{n - 2} + 2\right) =
2^{3}\left(a_{n - 3} + 2\right) = \cdots =  2^{n}\left(a_{0} + 2\right) = 7 \times 2^{n}
\\[5mm] \implies & \bbox[15px,border:1px solid navy]{a_{n} = 7 \times 2^{n} - 2}
\end{align}
Answer: Leu us consider the general case of $$a_n=\alpha\, a_{n-1}+\beta$$ Let first $a_n=b_n+\gamma$ which makes
$$b_n+\gamma=\alpha\,(b_{n-1}+\gamma)+\beta\implies b_n=\alpha\,b_{n-1}+(\alpha\gamma+\beta-\gamma)$$ To come back to something simple, let (assuming $\alpha\neq 1$)
$$\alpha\gamma+\beta-\gamma=0 \implies \gamma=\frac \beta {1-\alpha}$$ So, we are left with
$$ b_n=\alpha\,b_{n-1} \implies b_n=c \,\alpha^{n-1}\implies a_n=c\, \alpha^{n-1}+\frac \beta {1-\alpha}$$


Finding wordpress file in theme editor using the theme name

Question: In the wordpress admin dashboard, on the pages tab, when you edit the page, there's a section called "Page Attributes". One of the options is "Templates", which opens a drop-down list of templates available.
Is it actually possible to find which template name corresponds to which file in the theme editor without looking through every single file in the theme editor?
Answer: I'm not entirely certain I understand what you mean but whenever a Page Template is set WordPress also sets postmeta with a specific key and value. The key is called _wp_page_template and the value holds the template location relative to the theme. So you could do this:
$pages_with_templates = new WP_Query( array(
    'post_type'         => 'page',
    'posts_per_page'    => 20,
    'meta_key'          => '_wp_page_template',
) );

This will return a list of pages that have templates, you could narrow it down even more by supplying a value:
$pages_with_this_template = new WP_Query( array(
    'post_type'         => 'page',
    'posts_per_page'    => 20,
    'meta_key'          => '_wp_page_template',
    'meta_value'        => 'template-fullwidth.php',
) );

Now, when I said relative to the theme I mean that if you are using a sub-directory such as: theme-name/page-templates/template-fullwidth.php the postmeta value will hold: pages-templates/template-fullwidth.php.
There's also a conditional to test if the current page is using a specific template:
if( is_page_template( 'template-fullwidth.php' ) ) { ... }

Finally, if you're using the body_class() function - WordPress will assign a specific class based on the template to the body tag which you could target if you feel so inclined.


How do I add a wireless hotspot to my project?

Question: I just read on the description of a YouTube vid that Parrot AR Drone creates its own wifi hotspot. How does it do that? Is it possible to do a similar thing for a UAV project I've been thinking about?
Answer: It has hardware inside that allows it to act just like a wireless router.
If you wanted to add a wifi hot spot to the UAV project you would effectively need to add a wireless router inside your device. If you had a PC connect you could them give it special drives so what it sends over wifi is what your device needs to be controlled.
To keep it simple, this will not be an easy task.
Simpler methods
Roving Networks has some great solutions if you have a connection point. Your microcontoller interfaces through serial and it can act as a bluetooth hotspot. They also have modules that connect to wifi and then you can connect through sockets. This is relatively easy to do with C or java, as they have examples. The microcontroller will still just pipe serial data.
 Past Experience with Roving Networks
In my senior design project we used a roving networks bluetooth module to get a bluetooth signal from a sensor connected to the OBD-1 Connector on a car. We placed the device underneath the dash and with a dongle from 40 feet (no line of sight as it was under the dash) still had a signal without a problem. This allowed easy debugging.
When you pick bluetooth the class determines the maximum range, you can get a class one radiator and they can actually use what could be licensed as class three. They just paid the licensing fee to go higher, but chose not to. The roving networks module actually used the maximum power of a class one bluetooth device and coupled that with good receiver sensitivity. The range was very well done.
Comment: Thanks! I guess I'll have to use *less* advanced methods (bluetooth?) for now.
Comment: @gomek, I added more information.
Answer: I would buy a DD-WRT compatible router and flash DD-WRT on it, so you can get features like attached storage and hotspot management. Add ethernet to your device with whatever module you can get and connect them with a patch cable. Then on the software side, you could use Zerconf to let your client know what services it can access, e.g. video and control streams. I believe that many of these routers also support adding an RS232 serial port, and maybe you can communicate to the network via that, but I'm not sure, so you wouldn't have to add an ethernet module.
Comment: Interesting approach, It seems like it would not feasible for a real project, but for tinkering, very good idea.
Comment: yeah, probably, would at the least be rather large for a uav
Comment: The size would probably be prohibitive on a plane.
Answer: As an alternative to putting an access point onboard, there are some cellphones and PDA's that might have this functionality. They might be smaller and carry their own batteries but might add weight.


Experience of including checksum in all emails

Question: I would be interested to hear any advice or experience of including a checksum link in all emails sent to our various newsletter lists.
We're interested in doing this because we have quite a variety of email lists on different topics. This means an opt-out link (which we obviously include as well) is quite a blunt tool for controlling what sort of content people receive. We would rather regularly offer them the option of updating their preferences if they're not getting the email newsletters they want from us.
Does anyone include a regular email checksum link in their emails? Have you run into any problems doing so?
Answer: I've run checksum on all emails to over 160K recipients without issue. Just make a profile or respective CMS form (Drupal webform / Caldera Form) that allows them to select the public email groups you want them to opt into or out of.
I like to extend the checksum expiration to say 30 days.
Comment: good point re checksum life - it often gets overlooked


Can I avoid free writing?

Question: We write the best way, not when trying to perfect every sentence as we write our first draft, but when writing down our thoughts and not revising them till we finish that draft. Now in some books I have read, the authors advises their readers to use free writing to come up with material for their works. But I cannot imagine myself to use free writing, because it is not easy for me to write without stopping. I think I need to write more slowly, setting down only those thoughts that are meaningful, and revising those thoughts that are not what I intended them to be, not to make them clear or graceful, but to make their meaning precise.
Answer: I shall go against the flow and say that some people do not work well with free-writing.
Ggiaquin does a great job explaining why it is a helpful technique and, especially when trying to get over a writer's block, I'd quickly suggest it.
However, I understand the OP's point. My writing is very much driven by the character's emotional state (whether they're cool headed or in the throes of melodrama). The narrator's voice must always strike the right voice. If, for some reason, the sentences come off slightly out of character or if the emotion conveyed isn't quite right, then that is an equivalent to someone interruptiong me. It kills the flow.
What I do, in order to get the right voice in my head so the writing flows quickly and in character and also in order to get the right emotion, is to stop writing and to play the scene in my head a number of times. I go over the emotion, the actions, the words. I become the main character of the scene and repeat it over and over (doing so while doing a completely physical activity, like vacuuming, can help). Then I get inside the other characters and make sure their actions and reactions are also in character. Finally I can sit down and write because the voices and the emotions are just right. I have written over five thousand words in a sitting after doing this preparation. The later editing comes down much more to just spelling and getting a few synonyms, because the events and the emotions usually come out right from the start.
In a way, it's also a form or free writing in ggiaqin's sense - it allows to write without being interrupted, whether by your inner editor or by a feeling that something is off which kills your progression. Just prepare yourself until you've got the right tone for your thoughts. Or perhaps just go over your thoughts without writing them in order to improve them, to help them evolve into the right idea. Once you feel the right idea booming inside you, you'll be able to write non-stop, fed by that feeling.
Comment: @SF: This is why the old saying "know thyself" is so important. One must understand what works for oneself and *why* in order to improve one's process in a way that holds true to what comes naturally.
Comment: Myself, I write "in bursts". The story lasts in my head uninterrupted, but it's way too broad to be put down. Focus on unimportant details, distant events, echoes of the past, logistics of some technologies, the whole world coming to life. It's way too broad - and most of it is unimportant. So, after a bit has played out, I jot down the main events, dialogues, catch general landscape etc. When editing, I supply detail from memory. But there's just no way to get that.
Comment: I write "I took a ride up the enormous screw pump to the crest of the dam in a tiny boat", which is irrelevant to the story but just what occupied time of a secondary cast character. And in the background there's the lore of rafters who transport goods all over the city with tiny boats, through a grid of underground canals, and take their boats up the screw pumps after each circuit. Infrastructure to keep water flow and level constant, strict regulations of cleanliness as that's drinking water, taverns and legends of that folk, but that's not relevant! Just that one sentence makes it in.
Comment: I do exactly what you do. Especially with dialogue, I'll think it all out in my head - including all pauses, stutters, gestures, facial expressions, etc. Then once I've got the wording and flow working I can sit down and write that all without stopping, adding in the finer detail after. Then again, I do write a lot of dialogue.
Answer: You are still missing the point of free writing and many of our suggestions in your previous questions.  The whole point of free writing is not to kill your flow.  Think of it this way... you are watching a movie... someone comes in and talks to you so you pause it.  Play it for another 5 minutes, someone else comes in and talks to you so you pause it.  Then you play again.  Again someone interrupts you and you got to pause the movie again.  You can't enjoy the flow and pacing of the movie if you are having to pause it every 10 minutes.  You also have to spend time trying to remember where even you left off and what just happened.
I understand you want to slow yourself down.  This still causes the main issue of stopping yourself after every sentence.  Free writing does not necessarily mean  you rush through your writing with every first thought in your head.  It simply means that you allow yourself to turn off the editor/revision mode in your mind and allow thoughts to be put to paper without critique.  You can do this as fast or slow as you want, but the key is to not allow yourself to go back and edit or think if the sentence needs to be changed before writing.
That seems to be your biggest struggle because you want to control and force your words a certain way.  It is hard to build rhythm and flow and elegance if you are trying to take your foot and jam it in.  That's what it feels like you are trying to do to me.  You need to let go and relax and stop looking for perfection with your first try.
I feel like, in your situation based on the questions you have asked, you would really benefit from free-writing and it should not be avoided.  Especially if you want to learn how to build rhythm.
It's like playing an instrument.  Just let it flow man, if you make a mistake keep going, you don't see musicians stop if they make a mistake.  Often it is hard to hear mistakes when it is live because they keep the flow going.  Imagine if you were listening to a live concert and every time someone in the band messed up, they would stop and redo the song.  Concerts would be the whole day.  Some times, you need to look past the minor mistakes, the minor issues, to build the overall flow and then go back and change the couple of words you feel are out of place.
Answer: For most, that sort of deliberation is best done later, in edits or second drafts. However, if you'd like a way to force yourself to maintain a slower pace and think over words more before the first time you write them down, I've found that writing by hand is very valuable for that. It slows down the pace of your writing so that your mind can think of more different permutations of the words you have yet to write down.
Answer: There is story development and there is narration. You need to compose a story before you can narrate it. Some people are naturals at story development. For them the story flows so naturally that they can focus on narration from the moment they start writing.
Some people struggle with story development. Some address this with planning and outlines. Some do the story development in their heads before they start narrating. And some start scribbling down whatever comes into their heads and hope a story thread will emerge from it. This is what so called free writing is about.
Some people are naturals at narration. For them, the narrative flow emerges more or less intact in the first draft. For others, constructing a working narrative is a laborious process of many revisions. Don't expect your free writing story development to produce a great narrative. And don't confuse that process with the behavior of people who are both naturals at story and naturals at narration and can get a good first draft done first time out.
If free writing is your method for story generation, then don't worry about the writing details because this is not you first draft of the narrative, it is merely story generation. Be prepared (indeed, work with the full intention) to throw the entire thing away once you have found your story shape, and then begin the task of narration over from the beginning.

Can I avoid free writing?


Problem in deriving elements of Lorentz Group

Question: I am following a lecture series for Classical Field Theory in which they the lecturer uses the invariance of the length of a vector during a Lorentz transformation to derive the equation $$O^{T}\eta~O=\eta. $$
He derives this equation by the following these steps: Taking a vector $v$ and taking its length $$|v|^{2}=v^{T}\eta~v$$to be constant in a transformation we would get $$|v'|^{2}=v'^{T}\eta~v'$$
where $v'=O~v$, $O$ being the Lorentz transformation matrix. Further he writes $$|v'|^{2}=(v^{T}~O^{T})\eta~(O~v)$$ and then $$O^{T}\eta~O=\eta$$ for the length of the vector to be constant. Now my question is shouldn't the metric tensor $\eta$ itself not change under coordinate transformation and the equation should be $$O^{T}\eta'~O=\eta?$$ Because he then moves forth to derive some properties of $O$ using the equation $$O^{T}\eta~O=\eta.$$
Comment: possible duplicate: [Lorentz invariance of the Minkowski metric](https://physics.stackexchange.com/q/230495/84967).
Answer: This is a common confusion and it's just due to some tricky notation.

Every rank 2 tensor $A$ transforms as $A' = O^T A O$.
Your book has shown that for Lorentz transformations, the metric $\eta$ satisfies $\eta = O^T \eta O$.
Therefore, the metric transforms as $\eta' = \eta$ under Lorentz transformations. This is a very special condition that isn't true for a general rank 2 tensor.
Comment: where does this condition of  $\eta=\eta'$ come from?
Comment: @NamanAgarwal Just combine the first two equations.
Comment: I have learnt the general way in which tensors transform but have never heard of the in variance of the metric tensor...so i am asking why is it so?
Answer: Let's start with 3-dimensional euclidian world. Consider 3D rotations represented by matrices R. This should be demonstrative enough to show that the length of a 3-dim. vector is invariant under rotations.
$ |v|^2 =v^T v$ is the length of a 3D arbitrary vector. In the rotated system the length is $ |v'|^2 =v'^T v' = (v^T R^T)(Rv) = v^T v = |v|^2 $ since  the rotation matrices fulfill $R^T R = id \equiv 1$  It can be also be written like   $R_{ij}\delta_{jk}R_{kl}= \delta_{il}$  with $\delta$ as Kronecker symbol which now has the role of the metric, i.e. in component-free language we would write for it : $R^T\delta R=\delta$. Of course one can imagine a coordinate transformation to polar coordinates, then the corresponding transformation matrices P no longer fulfill  $P^T P = id$. But of course the length of an arbitrary vector is the same in polar coordinates than in cartesian coordinates.
Now we'll consider Minkowski space.  Actually the Lorentz-transformations $O$ are those types of coordinate transformations which fulfill $\eta = O^T \eta O$. The Minkowski metric is not changed by the Lorentztransformation is another phrasing of this fact. And as in euclidian 3D space we can carry out a coordinate transformation $C$ where $\eta' = C^T \eta C$.  But imagine a transformation which would only change the diagonal elements in $\eta$.
Normally:
$\eta = \left( \begin{array}{cccc} 1 & 0 & 0 & 0 \\  0 & -1 & 0 & 0 \\ 0 & 0 &-1 & 0\\ 0 & 0& 0 & -1 \end{array} \right)$
Imagine the matrix element $\eta'_{00}=1.2$  after the coordinate transformation instead of $\eta_{00}=1$. Then the invariant line element would  be   $ds^2 = 1.2 c^2 dt'^2 -dx'^2 -dy'^2 -dz'^2$.
In these coordinates the speed of light would be no longer $c$.  Actually such kind of coordinate transformations exist, but evidently these are no longer Lorentz transformations.


Can I take a bike on trains from Schiphol?

Question: I want to ride my bike from Ijmuiden to Schiphol railway station and take it on the train to Groningen - any problem with this?
Answer: You can take your bike on Dutch trains. Folding bikes that don't take more space than a normal piece of luggage travel for free, but they must be fully folded during the trip. However, for normal sized bikes you need to buy a bicycle day ticket ("dagkaart fiets") which costs 6,- and can be bought from the ticket vending machines. You will of course also need a ticket for yourself.
You need to load the bike in the special bicycle section of the train (marked by bicycle decals on the outside) and you are not permitted to take your bike with you during rush hour. (7:30 - 9:00 and 16:30 - 18:00).
BTW, if you want to get from IJmuiden to Groningen, why not board the train in Haarlem?
Comment: Thank you very much. We would prefer a direct train, but will think about your suggestion as Haarlem would be a nicer place to be than Schiphol!