How to generate new log files with every new run
How do I make log4j clear a log at startup?
Why does HDD activity slow the whole System down (on Windows 7)? If I copy a large amount of data from on drive to another (physical) drive my whole system is running slow.  I am using Windows 7 64bit version on an Intel Core 2 Duo 3 GHz.  This is the situation:   Very fast copying between two SATA disks.  Resource Monitor shows 80MB/s read, 70MB/s writes and 150MB/s total The total CPU load is about 3% There is plenty (>2GB) of free physical RAM left All partitions have enough (>10gb, >10%) of free space left and show low fragmentation Anti-Virus software is not active   This is the problem: No matter what I want to do while copying, it takes forever. Even tasks that do not need a lot of disk access (as they should work from RAM only), are extremely slow. The moment I stop the copying process, all the unfinished tasks finish at once. For example trying to open a new browser windows or explorer window will not work. If the copying is stopped 5 explorer windows popup at once.  My question is: why? What resource is exhausted, if CPU and memory are idle? And what part of my computer hardware I need to upgrade to get better behavior? Also read Psycogeek's comment for further questions in this direction.  If your answer is, that everything needs HDD Access, which is blocked by such an activity, then my question is: Is there a way to copy something on your system without rendering it unusable until its done? (which can be hours, if >500g have to be copied). Does GTA V Online Network Merge Xbox 360 and PS3 players? Foreign words reborrowed back into English Wikipedia mentions several English words that have been :   Anime comes from animation and has been reborrowed into English to mean Japanese-style animation. Puroresu comes from professional wrestling and is a term for Japanese-style professional wrestling. Kosupure comes from cosplay (an abbreviation of costume play) and refers to the practice of dressing in costumes of anime and video game characters.    Do you know other examples of word reborrowings from Japanese or other languages back into English, or vice versa? How do you turn off developer mode on an s5? I turned developer options 'off', but is there anything else that needs to be done? Not my phone so don't want to mess anything up :-) Is there an idiom that means "revealing a secret unintentionally"? I am thinking there could be an idiom that states that you or someone revealed a secret unintentionally? Can you think of an idiom like that? I am looking for an idiom I can use to write a blog post about the recent incident where Secretary Pompeo unintentionally revealed the dirty secrets behind the CIA. Remove impossible badges from per-site metas Per-site metas lists some badges that are impossible to get. For example  lists:         But these are impossibly to get because per-site metas do not support bounties, were not in a beta stage or Area 51 proposals. I therefore suggest that these badges are removed from the per-site metas. They have no function and they are confusing. There are already badges that are unavailable on per-site metas but available on the main sites:    Convention Quorum  This seems to suggest that per-site metas should only contain badges that can be possibly awarded. Why is the shape of lightning or an electric spark a zig-zag line? Why is the shape of the  (or an electric spark) always of a zig-zag nature? Why is it never just a straight line?     . Valid references on origins of Machine Learning, Statistical Learning and Data Mining Center of mass in n dimension, possible? Is it possible to calculate the center of mass for some 20-dimension ($x_i, i=1,\ldots,20$) particles? If it is possible, how can I do that? Is the word "management" singular or plural? Almost sure convergence of the Poisson process Let $N = \{N(t) \}_{t\geq 0 }$ be a Poisson process. I already know that $N(t)- \lambda t$ is a martingale where $\mathbb{E} [ N(t) ] = \lambda t$.   I want to prove that $$ \frac{N(t)}{t} \rightarrow \lambda, \quad t \rightarrow \infty \quad \text{ a.s.}. $$  To prove this I received a hint that I should use the martingale law of large numbers which states that:  Theorem: (Martingale LLN)  Let $S= (S_n = \sum_{k=1}^n X_k)_{n=1,2,\ldots}$ be a martingale with respect to the filtration $(\mathcal{F}_n)_{n=1,2,\ldots}$. Then $\sum_{k=1}^n X_k/k$ converges almost surely on the set $\left\{ \sum_{k=1}^\infty k^{-2} \mathbb{E}\left[ X_k^2 \mid \mathcal{F}_{k-1} \right] &lt; \infty \right\}$. Hence $S_n/n \rightarrow 0$ a.s. on the same set.  Now to use this theorem I think I need to use Doob-Meyer to decompose $N(t)$ as the sum of a martingale and an increasing process. Which would be the martingale $M(t) = N(t) - \lambda t$ and increasing process $A(t) = \lambda t$. But how is $M(t)$ the sum of a martingale? And I do not know how this exactly relates to the thing I have to prove. Thanks for any help. root of an odd degree polynomial Im asked to prove that a polynomial of an odd degree has a root. Im going to use IVT to prove this, but I'm wondering if I can use the assumption that an odd degree polynomial has either two cases:  $$ \lim_{x\to\infty}h(x)=+\infty \\ \lim_{x\to-\infty}h(x)=-\infty \\ $$ $$and$$ $$ \lim_{x\to\infty}h(x)=-\infty \\ \lim_{x\to-\infty}h(x)=+\infty \\ $$ Then by this there exists numbers $a,b$ such that $$ h(a)&lt;0&lt;h(b) $$ $$or$$ $$ h(b)&lt;0&lt;h(a) $$ Which I think would prove that odd degreed $h(x)$ has at least a root. Or is there a more convincing way to show that there are numbers in $h(X)$ greater than zero and less than zero?  edit: (sorry about the bad limit notation) Where to post questions asking for expert opinion? After my lie down, I posted  on SO. As I suspected would happen, it got moved to programmers. Unfortunately, the kind of people I'm interested in getting answers from (litb,skeet et al - the top SO programmers in their respective disciplines) don't frequent Programmers much. So my question is, where to ask somewhat non-specific questions of high-powered users? Difference between $\Delta$, $d$ and $\delta$ I have read the thread regarding , but it does not answer my question.  I am confused about the notation for change in Physics. In Mathematics, $\delta$ and $\Delta$ essentially refer to the same thing, i.e., change. This means that $\Delta x = x_1 - x_2 = \delta x$. The difference between $\delta$ and $d$ is also clear and distinct in differential calculus. We know that $\frac{dy}{dx}$ is always an operator and not a fraction, whereas $\frac{\delta y}{\delta x}$ is an infinitesimal change.   In Physics, however, the distinction is not as clear. Can anyone offer a clearer picture? Pokemon Go login issues after update I downloaded the July 30th update for Pokemon Go and when I open the app I'm prompted to login, But once I login, it redirects me to this page on Cookies::     If I click "Done" in the top left, it prompts me to login again! I've tried reinstalling the game, restarting my phone, etc. I can't much enable Cookies on the inline Safari browser. It doesn't make sense, and cookies are on in Safari (because I don't use Safari and they're enabled by default).  How can I fix this? IBM Slack links broken Waiting for user input with a timeout I have searched but apparently my google foo is weak. What I need is a way to prompt for user input in the console and have the request time out after a period of time and continue executing the script if no input comes in. As near as I can tell, Read-Host does not provide this functionality. Neither does $host.UI.PromptForChoice() nor does $host.UI.RawUI.ReadKey(). Thanks in advance for any pointers.  EDIT: Much thanks to Lars Truijens for finding the answer. I have taken the code that he pointed out and encapsulated it into a function. Note that the way that I have implemented it means there could be up to one second of delay between when the user hits a key and when script execution continues.  function Pause-Host {     param(             $Delay = 1          )     $counter = 0;     While(!$host.UI.RawUI.KeyAvailable -and ($counter++ -lt $Delay))     {         [Threading.Thread]::Sleep(1000)     } } How resilient is Ubuntu to repeated "power-off" shutdowns? My company is considering the use of Ubuntu as an OS for use on a hardware device.     It would be installed on compact flash drive - apparently this is not standard flash drive but a specific type of memory that is supposed to "cope" with immediate power shutdown (I am not sure how this is achieved but they are supposedly a "high end" card).    The units that would be run using Ubuntu are the type of units that will not be gracefully shutdown - the power cable would be removed and that is that.     Can anybody give me some advice on the potential problems that can occur? Is Ubuntu a good system that can deal with this kind of power outage and reboot successfully on next startup?     I realise that nothing is unbreakable, but is it a commonly used OS for an embedded setup? Is it asking for trouble to use Ubuntu in this kind of environment? I have an independent variable called "quality"; this variable has 3 modalities of response (bad quality; medium quality; high quality). I want to introduce this independent variable into my multiple linear regression. When I have a binary independent variable (dummy variable, I can code 0 / 1) it is easy to introduce it into a multiple linear regression model.  But with 3 modalities of response, I have tried to code this variable like this :  Bad quality      Medium quality      High quality       0                1                  0      1                0                  0      0                0                  1      0                1                  0   But there is a problem when I try to do my multiple linear regression: the modality Medium quality gives me NA:    Coefficients: (1 not defined because of singularities)    How can I code this variable "quality" with 3 modalities? Do I have to create a variable as a factor (factor in R) but then can I introduce this factor in a multiple linear regression? Blender is saving as a blend1 file, not blend I teach Blender to classes of game design students in the University of California and a student came to me yesterday with a problem I haven't seen before. She's created a very simple file, but when it's saved Blender puts a .blend1 extension on it every time, not the normal .blend. This means that after it's saved twice there are two .blend1 files in the directory, and no .blend file. I have no idea why this is happening. What has she done? Anyone seen this before?  thanks - Chris