How to make a minimal bootable linux (only with terminal) from kernel source code?
What are the minimum root filesystem applications that are required to fully boot linux?
evaluate $\int_{0}^{\infty}\cos(t) t^{z-1}dt=\Gamma(z)\cos(\frac{\pi z}{2})$ What is the advantage of using sudo apt-get autoremove over a cleaner app? Generate uniformly distributed weights that sum to unity? It is common to use weights in applications like mixture modeling and to linearly combine basis functions. Weights $w_i$ must often obey $w_i ≥$ 0 and $\sum_{i} w_i=1$. I'd like to randomly choose a weight vector $\mathbf{w} = (w_1, w_2, …)$ from a uniform distribution of such vectors.  It may be tempting to use $w_i = \frac{\omega_i}{\sum_{j} \omega_j}$ where $\omega_i \sim$ U(0, 1), however as discussed in the comments below, the distribution of $\mathbf{w}$ is not uniform.  However, given the constraint $\sum_{i} w_i=1$, it seems that the underlying dimensionality of the problem is $n-1$, and that it should be possible to choose a $\mathbf{w}$ by choosing $n-1$ parameters according to some distribution and then computing the corresponding $\mathbf{w}$ from those parameters (because once $n-1$ of the weights are specified, the remaining weight is fully determined).  The problem appears to be similar to the  (but, rather than picking 3-vectors whose $ℓ_2$ norm is unity, I want to pick $n$-vectors whose $ℓ_1$ norm is unity).  Thanks! Current in wire + moving charge next to wire creates magnetic force in the stationary reference frame OR electric force in the moving reference frame from special relativity due to change in charge density etc.... I think I understand this and I think it's super cool. Now here's the rub...  Current in wire + stationary charge next to wire creates no net charge. This is how nature behaves. I get it. My question is why can't I use the same special relativity logic as above, that is, current in wire cause electrons in wire to contract in accordance with special relativity so there has to be a net charge on the wire, which then acts on stationary charge next to wire.  I have been reading and reading and reading and I have come up with the following:  (1) When electrons in wire get accelerated to create current the distance between them actually expands in accordance with special relativity - something to do with bells spaceship paradox - which I am not going to pretend to understand  (2) This expansion from (1) above is exactly opposite and equal in magnitude to the contraction special relativity then causes and the expansion and contraction cancel out to keep the charge density in the wire constant and therefore no net charge on the wire  Here are my questions:  Is the explanation above correct? If so, please elaborate because i dont understand  If not correct, what is going on?  This is driving me absolutely nuts. How to mass delete your photos in your iPhone? I cannot do it in the phone itself, neither in iPhoto.  How can you delete all your photos in iPhone? consider the following subsets of complex plane $$\Omega_1=\left\{c\in\Bbb C:\begin{bmatrix}1&amp;c\\\bar c&amp;1\\ \end{bmatrix}\text{ is non-negative definite } \right\} $$  $$\Omega_2= \left\{c\in\Bbb C:         \begin{bmatrix}         1 &amp; c &amp; c \\         \bar c &amp; 1 &amp; c \\         \bar c &amp; \bar c &amp; 1 \\         \end{bmatrix} \text{ is non-negative definite } \right\}$$  Let $$\bar D=\{z\in\Bbb C:|z|\le1\}$$ Then 1) $\Omega_1=\bar D,\Omega_2=\bar D$  2). $\Omega_1\neq\bar D, \Omega_2=\bar D$  3). $\Omega_1=\bar D, \Omega_2\neq\bar D$  4). $\Omega_1\neq\bar D, \Omega_2\neq\bar D$  How to proceed? Thank you. How to prove $b=c$ if $ab=ac$ (cancellation law in groups)? Javascript Array.sort implementation? Which algorithm does the JavaScript Array#sort() function use?  I understand that it can take all manner of arguments and functions to perform different kinds of sorts, I'm simply interested in which algorithm the vanilla sort uses. convert a html book to a pdf file? How can I convert a html book (consisting of a number of html files linked to each other) to a pdf file on Ubuntu?   Hope the resulting pdf file can have bookmarks according to the structures of the html book.  The html book can be downloaded from . Extract it, and go to help, and the directory manual is the html book. Efficiently reverse the order of the words (not characters) in an array of characters I'm trying to  when I run into this:     "You have already deleted 5 of your own posts today; further deletes are blocked"      I found conflicting information on this very annoying limit:   This post from May 25, 2010: . This is marked . If this is no longer the case, please edit that question and flag it as . Then , indicates that the problem has risen from the dead -- despite :     Each time that I've seen it (pruning subpar answers), it's been a user who is deleting their own redundant zero-upvote answers. Can you tweak the algorithm slightly so answers with less than one upvote don't count towards tripping this flag?     (Emphasis added.) :     I don't mind it when         cleaning up redundant answers on questions that have multiple alternate good answers   cleaning up old, "less awesome" answers that are no longer reflective of the user's current skill level         (Emphasis added.)     So why do we have barriers in place, to making SO answers less, "less awesome"?      Proposed Solution:  Please let us (¿once again?) delete an unlimited number of our own answers, when they have zero up-votes and are not marked as the answer.  Otherwise, please edit the linked questions to clear up the confusion. Inform new users if they can upvote an answer they accepted I surprisingly often stumble upon answers which were accepted but clearly not upvoted by the asker. For example, the answer has not received any upvotes at all or the asker’s vote count is zero. While I acknowledge that , most such cases happen with new users, who have only recently received the privilege to vote and who upvote after a friendly reminder.  Given the anonymity of votes and that I do not check the asker’s profile for every question with an accepted answer I stumbled upon, I assume that there is a huge dark figure for this phenomenon. Also, I naturally most often spot this on my own answers, which makes reminding the asker of their privileges somewhat awkward.  I thus propose that users which accept an answer are reminded by a pop-up that they can upvote it, if:   They haven’t already upvoted it. They have the reputation required for voting. They have cast less than a handful of votes.   I consider the latter criterion to be better than an upper reputation for which the message is displayed, since I know at least one user with several thousand reputation points, who has cast much less upvotes or votes on answers than he has accepted answers on some sites (not that his acceptance rate or general feedback on answers is spectacular). Add a binary to my path I have an executable. I want to execute the executable in terminal with name only like other commands.  I can put my executable in /usr/local/bin or I could add its PATH to ~/.bashrc. Both will work.  What is better?  Is there  any difference? I have already had the same problem before. On that occasion, I found a program that could scan my entire hard drive for string pieces so I could recover it. Unfortunately I don't remember the name of the program. It had to access the hard drive data directly, normal searches won't get any data from the hard drive before formatting. I was browsing through the apt folder to try my proxy settings and I was unable to find the apt.conf file in Ubuntu 11.04. Is there any alternative file for it?  Adding proxy settings to 99-synaptic in apt.conf.d does not help as it gets overwritten everytime I restart the system. Thread Confinement "Specially" vs "especially" When should I use specially and when especially? What is "summoning sickness" and how does it affect my creatures? Note: this is intended to be a canonical question about summoning sickness.  "Summoning sickness", broadly, is the rule that stops you from attacking or paying {T} costs with a creature that you just played. But how exactly does it work? How does it interact with other rules and effects?  For example, if I'm trying to figure out how a creature is affected:   Does the status matter (tapped/untapped, face down/face up, etc.)? What if it came into play, but I didn't cast it? What if it's a token? What if it was on the battlefield when my turn started, but it wasn't a creature? What if it stops being a creature? What if it's a creature and also another card type? What if it's a double-faced card that just transformed? What if it changes control? What if it's a copy of another creature? Which of the creature's activated abilities can I use? Are any of its other abilities affected? Can I tap the creature to pay a cost that is not a {T} cost?   (These examples are primarily taken from questions about summoning sickness that have already been asked on the site) What are the integer solutions to $a^{b^2} = b^a$ with $a, b \ge 2$ There are 'n' candies and 't' boxes. Find the number of ways to place the candies in the boxes for each of the conditions (given in the problem). There are 'n' candies and 't' boxes. Find the number of ways to place the candies in the boxes for each of the conditions (all the candies must be spread out) : (a) candies and boxes are different; (b) candies of the same diiferent boxes should not be empty cartons: (c) candies equally new, boxes are different; Edit :(d) candies are different, the boxes are the same, there should be no empty boxes; (e) candies of different boxes alike.(Edit : candies are different, boxes are equal) Specify the display type that matches the placement, if possible. My Answers : (a) Each layout is encoded with a word of $n$ letters from the alphabet of 't' letters $\implies$ possible $n^t$ variants. (b) Write, $n$ candies in the form of balls ina line, we need to put $(t-1)$ partition in $(n-1)$ place, but we can't put two partitions on one place, so we get : $^{t-1}C_{n-1}$. (c) First we need to choose a candy in a box (in the first box $n$ ways, in the second box $(n-1)$, $\cdots$ in the $t-th$ : $(n-t+1)$ ways $\implies$ total $n!/(n-t)!$ methods, and then we distribute the remaining $(n-t)$ candies into $t$ boxes, this is encoded with owrds from the alphabets (for each candy $t$ variants) $\implies$ $t^{n-t}$. The Answer is : $\frac {n!}{(n-t)!}*t^(n-t)$ Are my answers (a), (b) &amp; (c) are correct? For (d) &amp; (e) I don't know how to proceed? Please help me.