I want a simple way to exclude the system folder from the searches in PowerShell.  I use the following script:  $mysys = 'c:\windows'     PS C:\&gt; Get-ChildItem -path . -Include *.txt -Exclude '$mysys' -Recurse   I basically want anything under c:\windows to be completely ignored, however, when I run the search, i continuously get errors as it searches under c:\windows; and in some cases also gives out results that it found.  Error: (why is it even going under c:\windows when I excluded it)   Get-ChildItem : Access to the path 'C:\Windows\System32\LogFiles\WMI\RtBackup' is denied. At line:1       char:1   + Get-ChildItem -path . -Include *.txt -Exclude '$mysys' -Recurse -Dept ...   + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~       + CategoryInfo          : PermissionDenied: (C:\Windows\Syst...es\WMI\RtBackup:String) [Get-ChildItem],   UnauthorizedAccessExcept     ion       + FullyQualifiedErrorId : DirUnauthorizedAccessError,Microsoft.PowerShell.Commands.GetChildItemCommand   For example, it includes: (this should all be excluded) (basically anything under c:\windows)  &gt; &gt;     Directory: C:\Windows\WinSxS\amd64_microsoft-windows-c..iser-inboxdatafiles_31bf3856ad364e35_10.0.14393.0_none_9eeac2cef7a25999 &gt;  &gt;  &gt; Mode                LastWriteTime         Length Name                  &gt;  &gt; ----                -------------         ------ ----                                                                                 &gt; -a----        7/16/2016   6:42 AM         855814 hwcompat_RS1.txt                                                                     &gt; ------        7/16/2016   6:42 AM           1764 hwexclude_RS1.txt                                                                    &gt; ------        7/16/2016   6:42 AM           1327 wucompat.txt   I basically want to do a recursive search under c:\ and then exclude whatever I don't want. Starting with c:\windows and everything under it.
Im trying to run the following code as a powershell script,but I cant get it to work. 1st,the following works with one -Include item but I cant seem to get it to work with multiple ones. 2nd, the -Exclude perimeter doesn't seem to work. I still get files from the C:\Windows and C:\Program Files directorys .  $Include = "*.zip","*.rar","*.tar","*.7zip" $exclude = "C:\Windows","C:\Program Files" Get-ChildItem "C:\" -Include $Include -Exclude $Exclude -Recurse -Force -ErrorAction silentlycontinue | Select-Object -ExpandProperty FullName   Note: The purpose of this script is to find all compressed files on the system. I know this is probably really simple but I just cant seem to get it to work.
How do I disable the screensaver/lock? When I'm watching a film in Mythtv the screen turns to black every 10 - 15 mins and I have to log back into Ubuntu. Very annoying!  How do I disable the black screen / screensaver / logout in Unity?  There no longer seems to be any options to turn the screen saver off as there were in Ubuntu prior to Unity. Equation numbers are shown in reverse parentheses I am using   \begin{equation} a = b \end{equation}   to write the equations in my paper. However, the problem is that the number related to each equation is not shown in the correct format like the picture   How can I fix this?  This is what I have at the first of my code:  \usepackage{graphicx} \usepackage[justification=centering]{caption} \usepackage{float} \usepackage{url}% typeset urls \usepackage{times} \usepackage{url} \usepackage{latexsym} \usepackage{fontspec} \usepackage{multirow} \usepackage{listings} \usepackage{setspace} \usepackage{listings} \usepackage{fontspec} \usepackage{amsmath} \usepackage{polyglossia} \usepackage{color} \usepackage{bidi} \newfontfamily\faFont[Script=Arabic]{Yas}  \newenvironment{Fa}{\begin{RTL}\faFont}{\end{RTL}} \newcommand{\fa}[1]{{\faFont\RL{#1}}} \newcommand\Mark[1]{\textsuperscript#1} \definecolor{backcolour}{rgb}{0.95,0.95,0.92} \definecolor{darkblue}{rgb}{0.95,0.95,0.92} \setmainlanguage{english} \setotherlanguage{farsi} \newfontfamily\farsifont[Script=Arabic]{Yas} Mint 18 will boot only to a black screen Conjugate class in the dihedral group What is the proper way to explain the twin paradox? The paradox in the  is that the situation appears symmetrical so each twin should think the other has aged less, which is of course impossible.  There are a thousand explanations out there for why this doesn't happen, but they all end up saying something vague like it's because one twin is accelerating or you need general relativity to understand it.  Please will someone give a simple and definitive explanation for why both twins agree on which twin is younger when they meet for the second time? Are ideal hashes possible to create? How do I log in to my personal Windows 10 using a FIDO2 key? I'd like to user a FIDO2 key to log into Windows 10. There are various guides explaining how to add a key to a Microsoft web account, or to Windows 10 sign in options, but neither result in showing up as an option when I try logging into Windows.  How can I configure windows to use my FIDO2 key to log in? On the , there is this line:      $p(\mathrm{height}|\mathrm{male}) = 1.5789$ (A probability distribution over 1 is OK. It is the area under the bell curve that is equal to 1.)    How can a value $&gt;1$ be OK? I thought all probability values were expressed in the range $0 \leq p \leq 1$. Furthermore, given that it is possible to have such a value, how is that value obtained in the example shown on the page? Plot $|z - i| + |z + i| = 16$ on the complex plane Plot $|z - i| + |z + i| = 16$ on the complex plane   Conceptually I can see what is going on. I am going to be drawing the set of points who's combine distance between $i$ and $-i = 16$, which will form an ellipse. I was having trouble getting the equation of the ellipse algebraically.  I get to the point:  $x^2 + (y - 1) ^2 + 2\sqrt{x^2 + (y - 1)^2}\sqrt{x^2 + (y + 1)^2} + x^2 + (y+ 1)^2 = 256$  $2x^2 + 2y^2 + 2\sqrt{x^2 + (y - 1)^2}\sqrt{x^2 + (y + 1)^2} = 254$  It seems like I'm and doing something the hard way. How can I use commercial at sign in Objective-C macro? Bijection from $\mathbb R$ to $\mathbb {R^N}$ How does one create an explicit bijection from the reals to the set of all sequences of reals? I know how to make a .  I have an idea but I am not sure if it will work. I will post it as my own answer because I don't want to anchor your answers and I want to see what other possible ways of doing this are. ASP.NET -> WCF concurrency problem How to obtain the sum of the following series? $\sum_{n=1}^\infty{\frac{n^2}{2^n}}$ How can I prevent Overflow for the Gamma function? I have a Dirichlet distribution from which I'm maximizing $\alpha$ by calculating the log likelihood with the following equation  $p\left(s|\alpha\right) = \sum\limits_{i=1}^O\log\left(\frac{n_i!}{\prod\limits_{j=1}^kn_{ij}!}\frac{\Gamma\left(\alpha_0\right)}{\Gamma\left(\sum\limits_{j=1}^k\left(n_{ij}+a_j\right)\right)} \prod\limits_{j=1}^k \frac{\Gamma\left(n_{ij}+\alpha_j\right)}{\Gamma\left(\alpha_j\right)}\right)$  I have a python script to calculate the log likelihood. It works for small values, but when $n_{ij}$ gets high $\Gamma\left(\sum\limits_{j=1}^k\left(n_{ij}+a_j\right)\right)$ and $\Gamma\left(n_{ij}+\alpha_j\right)$ python runs into overflow error (the max for math.gamma is between 171 and 172).   Is there a way to change the likelihood function so that $\Gamma\left(\sum\limits_{j=1}^k\left(n_{ij}+a_j\right)\right)$ and $\Gamma\left(n_{ij}+\alpha_j\right)$ don't run into overflow errors. Can I just divide the values in $\Gamma$ by for example 100, if I then compare the likelihood between $p(s|\alpha)$ with different $\alpha$ values do the best $\alpha$ values still have the highest likelihood? Count the number occurrences of a character in a string Why does this excerpt say that unbiased estimation of standard deviation usually isn't relevant? I was reading on the computation of the unbiased estimation of standard deviation and the source I read stated      (...) except in some important situations, the task has little relevance to   applications of statistics since its need is avoided by standard   procedures, such as the use of significance tests and confidence   intervals, or by using Bayesian analysis.   I was wondering if anyone could elucidate the reasoning behind this statement, for example doesn't the confidence interval use the standard deviation as part of the calculation? Therefore, wouldn't the confidence intervals be affected by a biased standard deviation?  EDIT:  Thanks for the answers so far, but I'm not quite sure I follow some of the reasoning for them so I'll add a very simple example. The point is that if the source is correct, then then something is wrong from my conclusion to the example and I would like someone to point how how the p-value doesn't depend on the standard deviation.  Suppose a researcher wished to test whether the mean score of fifth graders on a test in his or her city differed from the national mean of 76 with a significance level of 0.05. The researcher randomly sampled the scores of 20 students. The sample mean was 80.85 with a sample standard deviation of 8.87. This means: t = (80.85-76)/(8.87/sqrt(20)) = 2.44. A t-table is then used to calculate that the two-tailed probability value of a t of 2.44 with 19 df is 0.025. This is below our significance level of 0.05 so we reject the null hypothesis.  So in this example, wouldn't the p-value (and maybe your conclusion) change depending on how you estimated your sample standard deviation? iPhone 6s with iOS 12.4 not connecting to MacBook Pro mid2015 with macOS 10.14.6 I am using an iPhone 6s with iOS 12.4 and a MacBook Pro mid2015 with macOS 10.14.6. Since recently (I am not exactly sure when it started), I cannot charge the phone with my computer anymore. As soon as I plug the phone in, it will play the charging sound repeatedly. The right-hand side port sometimes works, the lefthand side port never works. When I connect my old iPhone 5 (using the same cable), it charges without any issues. My iPad mini 4 shows the same issue.  Sometimes the "Do you trust this computer" setting flashes on the phone and disappears before I can click anything.   How can I fix this?  Update 1  Sometimes I get the Software Update dialogue in macOS. After approx. 2 minutes it shows the following:     Update 2  For some reason the issue disappeared for a while but is back now. Disabling "Settings" > "Touch ID &amp; Passcode" > "USB Accessoires" seems like it makes the problem a bit less bad, but not go away.  Update 3  This is driving me crazy. I upgraded to Mojave 10.14.3 mostly to get rid of the issue. It persists. Some more random information: Before logging in (Filevault pre-boot authentication), the phone will charge fine. Only when a user account is loaded, the issue appears. The likelihood of a successful connection increases with the battery state of the iPhone. Workaround 2 in my answer below suggest that this a "Trust issue" from the iPhone's side. I suppose the solution will have to be hidden somewhere there...    What I tried so far (will update):   Reset Privacy settings on iPhone Different (original, almost new Apple) lightning cables   Remove and add "iPhone USB" in Network Settings  SMC reset (), PRAM reset Upgrade to latest iOS 12.4 and MacOS 10.14.6 In the movies, the Death Eaters leave a smoky trail behind them as they fly. As the Order arrive in the Ministry of Magic in Order of the Phoenix, they leave a silvery trail behind them. In the books, there’s no mention of how they’re doing this. And J.K. Rowling said in the books that only Voldemort and Snape could fly like this; first seen in the Battle of the Seven Potters.  Please can somebody explain how the Death Eaters are able to fly like this? I am trying to host some static content in an Amazon S3 bucket and to have that content available through my own domain.  The bucket in question is called "e.tl-dr.org" and I have "index.html" set as the index document. I can visit  and I see the contents of index.html (just "test"). This works fine.  I also have added the CNAME entry for "e.tl-dr.org" pointing to "s3.amazonaws.com" from within my registrar's site. (I am not using the AWS Route 53 DNS services, which is what most tutorials about this seemed to be geared at.) So now "" correctly shows the file, but just the bare domain only gives me S3's standard 403 message.  Is there anything else I need to set up to get this working? pgfplots and using axis cs to add points I am trying to mark two inflection points using a foreach loop in a pgfplot, but it isn't working.  \documentclass[tikz]{standalone} \usepackage{pgfplots} \pgfplotsset{compat = 1.10}  \begin{document} \begin{tikzpicture}   \pgfmathsetmacro{\infx}{1/sqrt(2)}   \pgfmathsetmacro{\infy}{exp(-.5)}   \begin{axis}[     xmin = -3,     xmax = 3,     ymin = -0.1,     ymax = 1.05,     domain = -4:4     ]     \addplot[blue, samples = 500, smooth] gnuplot {exp(-x^2)};      \foreach \x/\y in {\infx/\infy, -\infx/\infy}{       \draw[red] (axis cs: \x, \y) circle[radius = .025];     }   \end{axis} \end{tikzpicture} \end{document}   I am being told:  Undefined control sequence.^M &lt;argument&gt; axis cs: \x ^M                        , \y ^M l.34   \end{axis}^M