UTF-8 form submit in JSF is corrupting data
Unicode input retrieved via PrimeFaces input components become corrupted
How to effectively use the man pages? I am looking forward to mastering linux. I have been repeatedly told to refer to man pages when you are in doubt.   Though I am very comfortable with the commandline, I find it very difficult to quickly and efficiently use man to find help with commands. Hence I end up googling up how to get things done. It is even more painful when the system I am using does not have internet access and I have to walk back to my office to get help from the internet.  How does one master man pages? What are the most common tricks that can be used to quickly get whatever you want from the man page? What are the most commonly used keyboard shortcuts? Capacitor Voltage Rating How to find the voltage rating of a capacitor after knowing the capacitance value.  Example, For a power supply, If the input voltage is 60V and output is 5V. The input capacitor(C1) value is 100uf and output capacitor value is 1000uf.  What is the voltage rating for both the capacitors and how to find them. How to integrate $\frac{1}{\sqrt{1+x^2}}$ using substitution? How you integrate $\frac{1}{\sqrt{1+x^2}}$ using following substitution? $1+x^2=t$ $\Rightarrow$ $x=\sqrt{t-1} \Rightarrow dx = \frac{dt}{2\sqrt{t-1}}dt$... Now I'm stuck. I don't know how to proceed using substitution rule. What diagnostic plots (and perhaps formal tests) do you find most informative for regressions where the outcome is a count variable?  I'm especially interested in Poisson and negative binomial models, as well as zero-inflated and hurdle counterparts of each. Most of the sources I've found simply plot the residuals vs. fitted values without discussion of what these plots "should" look like.  Wisdom and references greatly appreciated. The back story on why I'm asking this, if it's relevant, is .  Related discussions: Does the shape of a containter affect the apparent mass of liquid inside it when measured by a scale? For both containers it is true that:  $p_{bottom}=p_{atm}+\rho gh$ and $F_{bottom}=a*p_{bottom} \iff F_{bottom}=a*p_{atm} + a\rho gh$  I do not know how a scale functions, but I guess that the only force it can count is the force by the liquid on the bottom of each container (the only surface that is in touch with the scale is the bottom of the container). Thus, if we measured the mass of these two masses of water (lets assume that the mass of the containers is negligible) it would appear to be the same in each case. Am I right? Let's say I have the domain johnsmith.com and I want people to reach me via email, what is the best email username to use?  Some examples:   john@johnsmith.com - redundant john.smith@johnsmith.com - redundant and looks kinda stupid mail@johnsmith.com - makes sense, but looks very "technical" me@johnsmith.com root@johnsmith.com - for the geeks among us ;-)   Of course, technically I can simply say that I will be able to receive *@johnsmith.com, however, for a better user experience I still just want one email address for public presence (website, business cards, etc.).  Any suggestions? Quite simply (and similarly to my other questions about previous versions of this feat  and ) I want to know if this feat is balanced and if not then what should be done to improve it? Since the last iteration I have changed the wording as per David Coffron's answer, increased the time and monetary cost as well as added in the action requirement to activate the rune as per Ruse's answer and increased the costs as per linksassin's answer     Rune Caster      Prerequisites: ability to cast at least one spell of 1st level or higher      When you take this feat you can imbue your spells of 1st level or higher into a rune by casting the spell as a rune, this means that you must have the object you want to put the rune on within reach for the entire duration of the casting as well as any tools required to make the rune.      When casting a rune you add the time listed in the cost time table to the casting time and the cost listed in the cost time table to the components of the spell in accordance with the stored spell.      \begin{array}{|l|l|l|} \hline \text{Spell level} &amp; \text{Time (hrs)} &amp; \text{Cost (GP)}\\ \hline 1 &amp; 1 &amp; 50 \\ \hline 2 &amp; 2 &amp; 100\\ \hline 3 &amp; 4 &amp; 500\\ \hline 4 &amp; 6 &amp; 1,000\\ \hline 5 &amp; 8 &amp; 5,000\\ \hline 6 &amp; 12 &amp; 10,000\\ \hline 7 &amp; 16 &amp; 50,000\\ \hline 8 &amp; 18 &amp; 100,000\\ \hline 9 &amp; 24 &amp; 500,000\\ \hline \end{array}      When making a rune you choose a trigger which is touch and/or command word and can be specified to only a group of people/creatures or a body part. When defining creatures that can activate the rune you may be as specific or general as you want. The DM interprets the designated creatures as your character would have interpreted them when you made the rune.      When you store a spell in a rune some of the ranges are altered, a range of touch becomes a range of self, a range and target keeps the same range and the person who activates the rune designates the target and range with an aoe sets the origin to the center of the rune, lastly a range of self stays the same.      When a rune is activated the spell is released acting as if it had just been cast without requiring any components or concentration. The rune then disappears leaving no trace of its presence. To activate a rune you must complete the trigger, this means speaking any command words and physically touching the rune each if applicable, this requires the activator to use the object interaction action while within reach for touch runes and while within 60 ft for command words. If both triggers are used then they must both be fulfilled within the same turn. Relationship between $\operatorname{ord}(ab), \operatorname{ord}(a)$, and $\operatorname{ord}(b)$ Another homework problem from my Group Theory class.  Let $a,b$ be elements of a group, $G$.  Let $\operatorname{ord}(a)=m$ and $\operatorname{ord}(b)=n$. Let $a$ and $b$ commute. Prove: If $m$ and $n$ are relatively prime, then the $\operatorname{ord}(ab)=mn$.  So I am having trouble starting off on this problem.  Here is what I believe I know:  $a^m=e$ and $b^n=e$ [as defined by the order of the elements] which leads $a^m=b^n$  $\operatorname{ord}(ab)=mn=\operatorname{ord}(ba)=nm$ as defined by commuting.  $\gcd(m,n)=1$ as defined by $m,n$ being relatively prime.    I don't know how to start this proof. Do I want to to go the route of $a^mb^n=e$?  Then $(ab)^{mn}=e$?   Any tips to start this would be greatly appreciated!!! How to calculate hash value of a file in Java? I'm trying to install Ubuntu 12.10 alongside Windows 7 on my ASUS laptop and I'm new to all of this.   I'm using  the Ubuntu 12.10 64-bit ISO burned onto a CD.  The first time I tried to install it, Ubuntu said it did not detect any other OS, which meant I only had 4 options:   Erase disk and install Ubuntu (I don't want to do this) Encrypt new Ubuntu. Use LVM. Something else.   If I choose the Something else option, it brings me to the partition menu and says that I have 1 disk with free space of 750516Mb (750Gb), but that's not true because I have Windows 7.  I've already read through several questions and people have mentioned that you could only have 4 primary partitions. So I got hold of partition magic and removed my D: and E:, leaving me with primary C: partition and System reserved partition and a lot of unallocated space.  I restarted the laptop several times and booted the CD again and I got exactly the same as I did previously.  How do fix this problem and install Ubuntu alongside Windows 7?  EDIT 1  Here are my results for   sudo fdisk -l; echo; sudo parted -l; echo; mount; echo; df -h   WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.   Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x90050371     Device Boot      Start         End      Blocks   Id  System /dev/sda1   *        2048      206847      102400    7  HPFS/NTFS/exFAT /dev/sda2          206848   146368214    73080683+   7  HPFS/NTFS/exFAT  Warning: /dev/sda contains GPT signatures, indicating that it has a GPT table. However, it does not have a valid fake msdos partition table, as it should. Perhaps it was corrupted -- possibly by a program that doesn't understand GPT partition tables.  Or perhaps you deleted the GPT table, and are now using an msdos partition table.  Is this a GPT partition table? Yes/No?     After selecting YES  Yes/No? yes                                                                Error: The backup GPT table is corrupt, but the primary appears OK, so that will be used. OK/Cancel? What is the English equivalent of gatasan? Is there a way to give promo/coupon codes for people to download your app for free? Lie bracket for Lie algebra of $SO(n,m)$ How does one show that the bracket of elements in the Lie algebra of $SO(n,m)$ is given by  $$[J_{ab},J_{cd}]  ~=~ i(\eta_{ad} J_{bc} + \eta_{bc} J_{ad} - \eta_{ac} J_{bd} - \eta_{bd}J_{ac}),$$  where $\eta$ has is the definite symmetric form with signature $(n,m)$? If a question is in all-uppercase or all-lowercase, our quality filters should automatically reject it Proposal If a question on an English-language Stack Exchange site does not contain at least one uppercase and one lowercase letter, our quality filter should reject it. (We can make exceptions for sites which don't use a mixed-case alphabet, such as .) Justification The quality filter currently rejects neither all-uppercase nor all-lowercase posts. I've checked. The best Stack Exchange users use mixed case. If an asker is too lazy to use their Shift key, their question tends not to be of very good quality. Don't take my word for it. You can see proof. Sam Saffron helped me write  which lets you see with your very own eyes that what I am saying is true. Single-case askers tend to ask poor-quality questions such as:      In addition, posts which use only uppercase or only lowercase — even if they aren't riddled with typos or grammatical errors — tend to be hard to read. Capitalization aids readability. Why is this proposal not a duplicate? This proposal is not a duplicate of the older proposal . This is because it also deals with all-lowercase questions. All-lowercase questions are 50 times more common than all-caps questions.  Stack Overflow gets only about 100 all-uppercase questions per year; see .  Yet it gets about 5,000 all-lowercase questions per year; see . (These statistics are for Stack Overflow only; the rest of our network wasn't considered.) I suspect that the older proposal was declined for two reasons:  All-uppercase questions are rare.  Therefore, the effort required to block all-uppercase questions is too much.   This proposal is better. For just a bit more effort, the Stack Exchange developers can get a much richer reward. Conclusion What do you think of my proposal? Agree? Disagree? Thoughts? PS: This idea is modified and adapted from  by Stack Exchange user Gilles. My dear sir Gilles, I thank you. Note There's even a  which automatically detects questions with all-caps titles and alerts interested users and moderators. Is  && statement() the same as if() statement()? How to understand a volatility based ETF like VXX The ETF VXX is based on the volatility index VIX. If volatility goes up, VIX goes up and VXX goes up. Similar thing for the downside. Now when I buy an ETF like SPY, I can conceptually understand that I am buying a small portion of each of the underlying companies. So if an underlying company stock makes a move, the ETF SPY makes a move in  the same direction.  But when I buy VXX, what exactly is the underlying? It is VIX. I am unable to grasp the concept of 'volatility' as the underlying. I can visualise only stocks and commodities as the underlying because in my understanding, the unerlying needs to be something physical (let us say stocks are physical commodities for this example).  Can someone explain the concept of 'volatility' as the underlying?  Is the word 'underlying' even appropriate in this case or is the word 'underlying' only to be used for derivative products? Adjust sound notification per chat room At the top right of a chat room, just above the room title, there is a speaker icon. Clicking on this icon brings up the settings for "Sound notifications":    Currently, a change to this setting affects all chat rooms. Selecting "visible room" means that an audio notification is given for any activity in any room that is currently open in a browser tab (regardless of whether that is the active tab).  It would be useful to be able to adjust audio notification settings for individual rooms. For example, The Nineteenth Byte is quite a busy room, so I'd like to be notified only when mentioned. The Cornell Box is a much quieter room, and I'd like to be notified any time there is activity regardless of whether I am mentioned. Currently I can set all rooms to notify me of any activity, or I can set all rooms to notify me only when mentioned, but I can't choose a different setting for each room.  This would also be particularly useful when setting up a room for a very specific purpose, such as discussion of a particular question. I want to do an , then cross-validate model prediction accuracy with 80% data for training and 20% for validation, and calculate  for predictions.  Consider this dataset:    X     Y ----------  2.3    1  3.1    2  3.5    2  10.0   5  6.8    4  5.0    3  5.4    2  3.2    1   I did this:  x=c(2.3,3.1,3.5,10.0,6.8,5.0,5.4,3.2) y=c(1,2,2,5,4,3,2,1) myData=data.frame(cbind(x,y))  library("MASS") reg=polr(as.factor(myData$y)~myData$x,data=myData,method="probit")   I saw , but I couldn't fully understand. Suppose myValidationData contains 20% of data which I want to use for validation. So, I would do:  fit=predict(reg,type="probs") x=c(5.6, 5.1) y=c(3,3) myValidationData=data.frame(cbind(x,y))   This is how I tried to predict, but is it correct, when I want to cross-validate?  fit=predict(reg,data=myValidationData,type="probs")   How should I measure RMSE? And, how can I plot the prediction? The advantages and disadvantages of using Kaiser Rule to select the number of principal components Is the Kaiser rule (choosing only PCs with eigenvalues >1, ) a reasonable method to select the number of principal components to retain? What are its pros and cons? Animating eye texture in a head mesh I'm trying to animate a mesh with different eye textures but it's not working.     This is a texture made by me to animate but I still couldn't figure out how to do it. I've seen tutorials on the internet but they don't work to me.