Time complexity of nested loops?
Big O, how do you calculate/approximate it?
Can not start Chrome via command line I have a script that needs to run on multiple machines. The problem is, if I open a command line and type in chrome or chrome.exe, I get the same error message that it is not recognized as an internal or external command... I have already added it to my paths (as per screen shot below, see bottom entry in the paths) . It works this way on other computers.  The command prompt has been restarted (as has the computer) since updating the paths. Why does it not open Chrome as it does on my other machine(s)? Whilst entering C:\Program Files (x86)\Google\Chrome\Application\chrome.exe directly into the command line and pressing enter does make Chrome launch, I don't see why the path is not working. What are the limitations of healing magic? While reading Sorcerer's Stone, I just finished the chapter where Harry walks in on Snape and Filch bandaging Snape's leg.  In a previous chapter Neville falls off of his broom and we see that magic can easily heal his broken wrist.  If magic can heal an injury like broken bones, why wouldn't Snape heal his leg, which was just torn up by a 3-headed dog?  My initial thought was that only certain people specialize in healing magic, but while poking around this site I came across this question:   This shows that Snape had at least some healing abilities.  So why didn't he heal his own leg?  Are there limitations that prevented Snape from healing his own wounds? The situation is as below:  -------|----------------------------        |  stump |batsmen2   broken|batsmen1  here  |  -------|----------------------------   Is it a runout in the above situation? Example of a finite non-commutative ring without a unity Give an example of a finite, non-commutative ring, which does not have a unity.    I can't think of any thing which fits this question. I was thinking $M_2(\mathbb{R})$ but it has the identity. Any help is appreciated. How to be granted root rights while browsing files/directories with Nautilus I'd like to know if there a way to be granted root rights while using Nautilus 2.30 ?   For example I'd like to move some old folders of long unused users from the home directory - remains of previous distros (Debian).   Of course I can open a terminal, but I want to know if it is possible to do that with a mouse in Nautilus. SINGLE_EMAIL_LIMIT_EXCEEDED. What does it mean? To my knowledge there are three types of acceleration when a body (e.g. a rod) is moving in a circle about an axis. These are:   Angular acceleration : this is the rate of change of angular velocity. Tangential acceleration : this is the linear acceleration of the system in a tangential direction to the circle and equals the radius times the angular acceleration. Radial/centripetal acceleration : this is the linear acceleration of the system that is directed inwards towards the center of the circle.   I also think there are two types of velocity:   Linear velocity: this is its velocity in the tangential direction and is constantly changing Angular velocity or angular frequency: this is the rate of change of angle.   Is the above correct? And have I missed anything? Almost all passports I have seen have a place of birth field on them. For instance, on the US Passport,    Is there a specific reason to this? Are answers that just contain links elsewhere really "good answers"? I have often wondered at the practice on Stack&nbsp;Overflow, Server&nbsp;Fault, and the other sites where someone will ask a question and an answer will come in that says Look here: http://link elsewhere. Rarely will the link have exactly the answer necessary -- often it's an entire article -- yet these answers get voted up.  Why is that, exactly? I realize this is subjective, but my own thoughts are that one should try and give the answer (even if the answer is 'no, it can't be done' or 'no, I don't think it can be done' -- very different answers) and then if you have a link that explains it, go ahead and post it within the answer.  What does the community think about this?     For more information, see  in the . 'Thank you for taking your time writing' or 'Thank you for taking your time to write' ? A person gave me an answer on English.SE and I commented:     Thank you for taking your time writing this wonderful answer!   Now, looking at the sentence in retrospect, even though I am not a native English speaker (duh, otherwise I wouldn't be asking a question on ELL.SE), I find the sentence a bit odd.  To get my point across, let me rephrase the sentence:     Thank you for taking your time to write this wonderful answer!   With my relatively little knowledge and understanding of English, I feel that using 'writing' (as I did in the original sentence) emphasizes the very process of writing the answer, whereas using 'to write' emphasizes the mere fact that an answer has been given, and a wonderful one at that.  This is exactly why I feel the original sentence is a little bit awkward and the second, revised one would have been more apt.  Am I correct or are the quoted sentences virtually synonymous? Explaining to an 8-year-old why nothing can travel faster than light Present tense for future events Why does it sound perfectly natural to say Our flight leaves tomorrow at 6pm but weird to say It rains tomorrow at 6pm? What kind of scenario, if any, could make the rain sentence sound natural? Same update keeps showing up everyday Why are my SVG imports so small? I'm definitely a newbie with blender still, as I've dipped my toe in a bit being a video editor.  My issue is importing .svg saved from illustrator.  Just simple vectors with not too many paths.  Just a thick text company logo.  I want to bring in and extrude, light, etc.  I've done it before in older versions of blender with no problem.  Am I not doing something right? Can someone tell me how to get an eps saved as an svg from illustrator to size correctly? How does Newtonian mechanics explain why orbiting objects do not fall to the object they are orbiting? The force of gravity is constantly being applied to an orbiting object.  And therefore the object is constantly accelerating.  Why doesn't gravity eventually "win" over the object's momentum, like a force such as friction eventually slows down a car that runs out of gas?  I understand (I think) how relativity explains it, but how does Newtonian mechanics explain it? Interesting topics to research in mathematical physics for undergraduates How do I get whole and fractional parts from double in JSP/Java? How do I get whole and fractional parts from double in JSP/Java ? If the value is 3.25 then I want to get fractional =.25, whole = 3  How can we do this in Java? What is AC actually? What is actually alternating current (AC)? And direct current (DC)? I've been reading several books about basic electric circuits analysis and they are contradictory.   Some books say that AC is the same as the sinusoidal stationary state. That is, a sine or cosine function (actually, they are the same only shifted horizontally). For instance, \$v(t) = A \sin(\omega t + \phi)\$. Acording to these books, DC is totally stationary (static), that is, the voltage and current are not time-dependant (\$v(t) = k\$, where \$k = \mathrm{const.}\$). Currents have the same form as voltages on each of these cases. According to other books, AC is any current that is changing (that is alternating) his sign over time (\$t\$). With maths notation: \$i(t_1) &lt; 0\$ and \$i(t_2) &gt; 0\$ for some \$t_1\$ and \$t_2\$ where \$t_1 \neq t_2\$. It could have any shape as long as it's alternating his sign.   I'm inclined to think that in practice wins the first option but maybe it's better the etymology of the second option.  Some other cuestions have relation to this:   Is AC a voltage that is the sum of a sinusoidal stationary state and a constant voltage? For instance, \$v(t) = A \sin(\omega t + \phi) + k\$. Is AC a shawtooth wave? Intuition behind why order of a subgroup divides order of a group. Is AES in CBC mode secure if a known and/or fixed IV is used? I have a need to encrypt credentials for a third-party app used by a secured internal app. Over on ITSec.SE, I was helpfully shown a scheme to encrypt the third-party credentials based on a hash of the credentials for the internal app.   I picked AES as the encryption algorithm, but the problem is that the password-based scheme doesn't produce a "secret" IV. So, the IV must at least be known to an attacker (stored alongside the encrypted data). A hash value used for password verification could work, or I could just generate a pseudorandom byte array and drop it in the DB as a new column. I was further considering, for simplicity, to use a constant IV.   What adverse effect will either of these choices have on the security of the encryption? Does AES depend, as many block ciphers do, on an unpredictable IV? Does it matter if the IV is stored as unencrypted plaintext?