Plone email out errors from error_log
Error notification on plone 4
What's the significance of conditional and absolute convergence? I know how to find if a series is conditional or absolute convergence by taking the absolute value and seeing if that absolute sum converges (then the original sum is absolute). If the absolute diverges but the original converges, then that's conditional.   But my question is: is there a significance? Is absolute convergence series bigger than absolute? Does a series being absolute or conditional affect rate of convergence, or radius? Does it affect symmetry?   Looking at Google, I only found tests on how to find if it's absolute or conditional. But I want to find meaning or significance. Or at least more mathematical properties. How to uninstall a package installed from snapcraft? I used this command line  sudo snap install pwgen-tyhicks   to install pwgen but I can't findout how to use it. So I want to uninstall it. How to  uninstall it? So, I have about 7 actions users may need in my app, and I have to use text instead of icons because it is a customer requirement.  I can add only 3 actions to my toolbar on iPhone 6. On Android you have the hamburger menu (see image), but I have never seen it in iOS.       So, what is the appropriate concept in iOS to add many actions into a menu? I'm creating a color object using the following code.  curView.backgroundColor = [[UIColor alloc] initWithHue:229 saturation:40 brightness:75 alpha:1];   How can I retrieve RGB values from the created color object? Prove that for any piecewise smooth curve it is possible to find the parametrisation I can see by manipulating the expression why $\mathbb{E}X$ works out to be $\int_0^\infty 1-F(x)\,dx$, where $F$ is the distribution function of $X$, but what is an intuitive explanation for why that is true? If at each point we sum the probability $\mathbb{P}(X&gt;x)$, why should we end up with the expectation?  Thanks , to correct a misspelled library enum in an answer. Since the edit was only one character, I also had to add a superfluous sentence to get over the character limit required to edit a post.  I've hit this problem before in other edits, always in code snippets. Since the edit limit exists to prevent trivial edits, and since there are many cases where one character code edits are not trivial (= to == etc), would it make sense to have a lower edit minimum inside code snippets? Determiners: anyone versus someone The brightness of my laptop is reset to max on every restart. I tried the solution provided at  but had no luck.   This command   cat /sys/class/backlight/acpi_video0/max_brightness   Returns   cat: /sys/class/backlight/acpi_video0/max_brightness: No such file or directory   Then I found that I don't have a folder named acpi_video0, but a folder called intel_backlight:    Every time I increase or decrease the brightness using the brightness control keys, the values in brightness and actual_brightness get updated.  Is there any method I could follow to set the brightness to a fixed value on every boot and vary it as and when I need it using the brightness control keys? I have a quick question about updating my references from Bibtex.  I am using TexStudio as my Latex editor.  I have to make changes to some of the references.  I put the changes in the "references.bib" file.  I then compile the Bibtex and the main document I'm working on.  Sometimes the changes show up, and sometimes they don't, and I haven't figured out why. I have even gone as far as trying to delete the references by changing the filename, but the original references still appear.  Here's what I put in my main document:   \newpage %Puts in References  \bibliographystyle{unsrt}  \bibliography{references}   My references.bib file shows all the changes I have made.  Any suggestions are appreciated! No cycle containing edges $e$ and $g$ implies there is a vertex $u$ so that every path sharing one end with $e$ and another with $g$ contains $u$ There is a proof in my textbook for the following claim, which doesn't make a whole lot of sense to me.  My annotations are in bold.  Could someone perhaps elaborate on what's going on?  Claim.  If there does not exist a cycle containing edges $e$ and $g$ then there exists a vertex $u \in V (G)$ such that every path in $G$ sharing one end with e and another with $g$ contains $u$.  Proof: The claim trivially holds if $e$ or $g$ is a loop OK, so we assume that neither is. Let $P$ with vertex set $v_1, v_2, . . . , v_k,$ in order, be a path with $e$ joining $v_1$ to $v_2$ and $g$ joining $v_{k−1}$ and $v_k$. Let $f_i \in E(P_i)$ be the edge with ends $v_i$ and $v_{i+1}$. Let $j$ be chosen minimum so that no cycle in $G$ contains $e$ and $f_j$ We can do this because we know that at least the edge $g$ will not create a cycle by assumption, right?. We will show that $u = v_j$ satisfies the claim.  Suppose not. Let $C$ be a cycle containing $e$ and $f_{j−1}$ What if $f_j = e$?  then what cycle? a single vertex? and let $P′$ be a path from an end of $e$ to an end of $f$ Not sure what the book meant by $f$ here, any guesses? avoiding $u$. Choose a subpath $Q$ of $P′$ with one end in $V (C)$ and another in ${v_{j+1}, v_{j+2}, . . . , v_k}$ as short as possible. Then $C \cup Q \cup P$ contains a cycle containing both $e$ and $f_j$, a contradiction. (The last statement requires some case checking.) This ending seems a bit abrupt and non-obvious to me  Thanks for the help During Winterbash 2014, there was a hat called , which was earned by giving an answer scoring 5 or better to question that had a score of −3 or worse at the time of answering and later rose to a score of +3 or better.  I’ve already shared the . Those cases give me a great deal of confidence that this would be a challenging badge trigger that would produce good behavior with a minor tweak. Here are the Red Barons earned on other sites:    (Logan Maingi) Mathematics  (Mike Miller) Mathematics  (Hugo) English Language and Usage  (tchrist) English Language and Usage  (Mr. Shiny and New 安宇) English Language and Usage  (Darth Satan) Science Fiction and Fantasy  (DVK) Science Fiction and Fantasy  (rolfl) Code Review  (Heslacher and Hosch250) Code Review  (Edward) Code Review  (janos and Manny Meng) Code Review  (Mark Mayo, Rory Alsop and MeNoTalk) Travel      (DJClayworth) Christianity  (McMagister) Puzzling   Looking through the timelines, I’m convinced that the answerer’s votes should be excluded from the pre-answer question score calculation. Doing that would have reduced the number of Red Barons to 16 across the network. However, the cost of making a badge harder to obtain is worth the benefit of avoiding giving people an incentive to manipulate question scores¹.  To wrap up, the hat seemed to have encouraged a number of great answers and rescued some questions that would otherwise have been lost to time. My outstanding questions are:   Were there any problems on questions where people were attempting to earn the hat, but failed? (Or any other problems I didn’t observe.) If not, should we  or create a new badge? If we create a new badge, what should it be called?   I’m especially interested in feedback that counters my own bias in favor of this idea. If I’m missing any problems, I’d like to know about them now.    ¹ Several questions were downvoted, answered, edited (sometimes trivially)  and upvoted by the user who earned the hat. Maximum log level exceeded in Developer Console Recently I have regularly been getting the error message below when opening the Developer Console:     The Developer Console didn't set the DEVELOPER_LOG trace flag on your   user. Having an active trace flag triggers debug logging. You have 316   MB of the maximum 250 MB of debug logs. Before you can edit trace   flags, delete some debug logs.   It happens in sandbox and scratch orgs. Haven't tried in production.  This only started happening recently. It goes away after clearing the logs but comes back after a few test runs.  Also: the Debug->Clear->Log Panel action is not working for me -- the logs stay put. I can remove them using the Query Editor as described , but it's pretty tedious.  Two questions:   Does anyone know a way to prevent the logs from exceeding the max level? Perhaps by having old logs cleared out automatically? Is there a known issue with the Clear Log Panel action? I am using Chrome btw.   Thanks! Why can partial derivatives be exchanged? In the   post in this stack exchange, one of the answers to the questions of do partial derivatives commute is: Second order partial derivatives commute if f is $C^2$ (i.e. all the second partial derivatives exist and are continuous). This is sometimes called Schwarz's Theorem or Clairaut's Theorem. This theorem is in my textbooks, yet I cannot seem to find the proof in them. I have tried proving the theorem yet I have gotten stuck. So, what is the proof of Clairaut's Theorem, or why do partial derivatives commute? If the proof is too long, a link to the proof with an intuitive explanation will be sufficient. I'm looking to create a virtual printer that passes data to my .NET application. I want to then create an installer that installs both the printer and the .NET application.  It would we really nice to be able to write it all in C#, but I have a feeling that this will require a printer driver to be written is unmanaged code.  Does anyone know of a fairly clean tutorial or example of how to do this? Foolproof way to ensure Google news pulls the correct image for its thumbnails? Google news results have an acompanying thumbnail next to articles that show up in the results.    If Google's crawler can't find a thumbnail to pull from our site, it uses its next best guess from another site, therefore linking the image to another site but still uses our headline.  Example:  Headline from Reuters, Image from Livemint:   Our pages absolutely have images, they are not massive in file-size or dimensions, yet we are not having them pulled / crawled correctly.  We have read up on the suggestions from Google, and from others around the web and nothing is panning out.  Has anyone had any experience where they can ensure Google news will pull a thumbnail of our choosing? I am aware there are many questions similar to this on MSE but I am having trouble following any of the solutions given.   I have the function given by   $f(x) = \dfrac{xy}{x^2+y^2}\;$ for $(x,y)\neq (0,0)$ and $f(0,0)=0$  I have calculated the partial derivatives and found:   $$\frac{\partial f}{\partial x} = \frac{y(-x^2+y^2)}{(x^2+y^2)^2}, \quad \frac{\partial f}{\partial y} = \frac{x(-y^2+x^2)}{(y^2+x^2)^2}$$  Now I need to show the partial derivatives exist for $(x,y) = (0,0)$.  I am also asked to show it is not continuous at $(x,y)=(0,0)$, based on other answers I've seen it seems like this follows from solving the first part but I fail to see how that follows through as well.   I could just copy the solutions with my function in place as I have seen a lot of answers using the definition of the derivative, but realistically I do want to understand what the thinking behind this is.   Any help would be appreciated. $y'=$ ${-x+\sqrt{(x^2+4y)}}\over 2$ , $y(2)=-1$ Prove that the solutions $y_1$ and $y_2$ for the initial value problem   $y'=$${-x+\sqrt{(x^2+4y)}}\over 2$ , $y(2)=-1$  are:  $y_1=1-x$  $y_2={{-x^2}\over 4}$  And explain why the two solutions not contradiction with the theory of existence and uniqueness.  ( sorry I don't speak English well )  My answer:  For the initial condition :  $y_1=1-x$ Satisfy the initial condition  $y(2)=-1$  $y_1=1-2=-1$   And Satisfy the differential equation  ${y_1}^{\prime}=-1$  ${{-x+\sqrt{x^2+4y}}\over 2}={{-x+\sqrt{x^2+4(1-x)}}\over 2}$  $={{-x+\sqrt{(x-2)^2}}\over 2}$  $={{-x+x-2}\over 2}=-1$  L.h.s.=R.h.s.  $y^{\prime}={{-x+\sqrt{x^2+4y}}\over 2}$  Also $y_2$ Satisfy the initial condition  $y_2={{-x^2}\over4}={-4\over4}=-1$   And satisfy the differential equation.   $y_2^{\prime}={-x\over 2}$  ${{-x+\sqrt{x^2+4y}}\over 2}={{-x+\sqrt{x^2+4({-x^2\over 4})}}\over 2}={-x\over 2}$  And for second part of exercise:  ${\partial f\over \partial y}={1\over \sqrt{x^2+4y}}$  and this not defined when $x=2, \ y=-1$  So $f(x,y)$ no satisfy lipshtize condition in any rectangular has (2,-1), Lipshtize condition including uniqueness of solution, so no contradict with the existence and uniqueness.  True ?  If this also wrong I well be delet it , I answered by the same way of my teacher :( I'm making a trip back home (to the coast) shortly, and I would like to bring back sand from the beach with me as a keepsake or memento. It's just a short weekend trip, and I won't be checking any luggage, so I was wondering if it's even worth bothering trying to bring sand aboard the plane in my carry-on?  If so, what can I do to make the security screening as smooth as possible? I was planning on putting the sand in sandwich-sized plastic bags, enclosed in a larger quart- or gallon-sized bag. Convergence of $\sqrt{n}x_{n}$ where $x_{n+1} = \sin(x_{n})$ Consider the sequence defined as  $x_1 = 1$  $x_{n+1} = \sin x_n$  I think I was able to show that the sequence $\sqrt{n} x_{n}$ converges to $\sqrt{3}$ by a tedious elementary method which I wasn't too happy about.  (I think I did this by showing that $\sqrt{\frac{3}{n+1}} &lt; x_{n} &lt; \sqrt{\frac{3}{n}}$, don't remember exactly)  This looks like it should be a standard problem.   Does anyone know a simple (and preferably elementary) proof for the fact that the sequence $\sqrt{n}x_{n}$ converges to $\sqrt{3}$?