Extract Keys from list of dictionnary through function in Python
What does ** (double star/asterisk) and * (star/asterisk) do for parameters?
In Windows 8 I can reset everything and reinstall Windows. I assume this will clear my drive and start from scratch? Is that right? Does this create a Windows.old folder?  I see this dialog, but aren't my settings and preferences saved in the cloud? If I screw up my settings and reset like this, are my settings also refreshed back to defaults?  Since I use SkyDrive to sync my files, my personal files are safe, right?    Also, in Windows 8 I can refresh my PC without affecting files. Are my desktop and/or Windows store apps uninstalled when I refresh my PC?  I see this dialog, but I still am not sure. For example, when it says apps are "kept" does that mean I don't have to buy them again or are they installed after the refresh is over for me? I assume "from disk" means desktop apps? Or maybe corp apps?    What would motivate a user to choose between these two? I have a HP Pavilion dm4-2070us which has an Intel Corporation Centrino Wireless-N 1000 adapter.   The problem is that my computer doesn't show the wireless networks after I upgraded my system to Ubuntu 11.10. Following is my output for sudo lshw -class network:  *-network DISABLED          description: Wireless interface    product: Centrino Wireless-N 1000    vendor: Intel Corporation    physical id: 0    bus info: pci@0000:01:00.0    logical name: wlan0    version: 00    serial: 8c:a9:82:81:5a:30    width: 64 bits    clock: 33MHz    capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless    configuration: broadcast=yes driver=iwlagn driverversion=3.0.0-12-generic firmware=39.31.5.1 build 35138 latency=0 link=no multicast=yes wireless=IEEE 802.11bgn    resources: irq:42 memory:c2500000-c2501fff  *-network    description: Ethernet interface    product: AR8151 v2.0 Gigabit Ethernet    vendor: Atheros Communications    physical id: 0    bus info: pci@0000:08:00.0    logical name: eth0    version: c0    serial: 2c:41:38:07:f3:e3    size: 100Mbit/s    capacity: 1Gbit/s    width: 64 bits    clock: 33MHz    capabilities: pm msi pciexpress vpd bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation    configuration: autonegotiation=on broadcast=yes driver=atl1c driverversion=1.0.1.0-NAPI duplex=full firmware=N/A ip=192.168.1.7 latency=0 link=yes multicast=yes port=twisted pair speed=100Mbit/s    resources: irq:44 memory:c1400000-c143ffff ioport:2000(size=128)   The output for rfkill list all:  0: hp-wifi: Wireless LAN     Soft blocked: no     Hard blocked: no 1: hp-bluetooth: Bluetooth     Soft blocked: no     Hard blocked: no 2: phy0: Wireless LAN     Soft blocked: no     Hard blocked: no 3: hp-wwan: Wireless WAN     Soft blocked: no     Hard blocked: no   I have also searched about the status of the WiFi network being shown as disabled. Somehow everything pointed to the fact that my wireless device is switched off and it can be switched on from Windows only. However, I don't have windows partition and it has just Ubuntu 11.10 so I don't see any point in switching the device on in Windows. I have the following sequences $(a_n)$, $(b_n)=(a_{2n})$, and $(c_n) = (a_{2n-1})$.  I have to show that:   if $(b_n)$ and $(c_n)$ both convergence to $a$, then $(a_n)$ also converges to $a$; if $(a_n)$ converges then $(b_n)$ and $(c_n)$ also converge; there exist $(a_n)$ not converging but with $(b_n)$ and $(c_n)$ converging.   I am not sure how to solve this since I only know that $(b_n)$ > $(c_n)$ > $(a_n)$ on the terms how the sequences are defined. For aer.bst, citations with 3 or more authors are listed using et al. I need to modify the bibliography so that citations with 4 or more authors are listed using et al., but that citations with 3 authors have all the names written out. For example, I want "See Adams, Brown, and Clark (2003)" as opposed to "See Adams et al. (2003)." I'm using natbib with LaTex: \usepackage{natbib,har2nat}  In order to do that, I need to modify the function format.lab.names.abbr.  Might someone know how to do this?  FUNCTION {format.lab.names.abbr} { 'name.list :=   name.list num.names$ 'numnames :=   numnames #1 &gt;     { numnames #2 &gt;         { name.list #1 "{vv~}{ll}" format.name$ " et al." * }         { name.list #2 "{ff }{vv }{ll}{ jj}" format.name$ "others" =             { name.list #1 "{vv~}{ll}" format.name$ " et al." * }             { name.list #1 "{vv~}{ll}" format.name$ " and " *               name.list #2 "{vv~}{ll}" format.name$ *             }           if$         }       if$       field.used editor.field = {", eds" *} {} if$     }     {         name.list #1 "{vv~}{ll}" format.name$         field.used editor.field = {", ed" *} {} if$     }   if$ }   FUNCTION {format.lab.names.full} { 'name.list :=   #1 'nameptr :=   name.list num.names$ 'numnames :=   numnames 'namesleft :=     { namesleft #0 &gt; }     { name.list nameptr "{vv~}{ll}" format.name$ 'temp :=       nameptr #1 &gt;         { namesleft #1 &gt;             { ", " * temp * }             { temp "others" =                 { " et~al." * }                 { " and " * temp * }               if$             }           if$         }         'temp       if$       nameptr #1 + 'nameptr :=       namesleft #1 - 'namesleft :=     }   while$   numnames #1 &gt; field.used editor.field = and {", eds" *} {} if$   numnames #1 = field.used editor.field = and {", ed" *} {} if$ } So basically this proof centers around proving that (S,*) is a group, as it's quite easy to see that it's abelian as both addition and multiplication are commutative. My issue is finding an identity element, other than 0. Because if 0 is the identity element, then this group won't have inverses.  The set explicitly excludes -1, which I found to be its identity element, which makes going about proving that this is a group mighty difficult. InputStream returning NullPointerException (Java) I want to insert text at the top of an already existing file. How can I achieve this. I tried echo and tee but was not successful.  I was trying to insert repo line at the top of sources.list file from terminal.  Note  I need an one line quick solution, because another answer's method was known to me already I am trying get an unused server up and running, it booted fine but i was greeted with the login window and none of the known passwords seem to work. The server I am trying to get to work is not a Domain Controller and has not been used in a long time.  OS: Windows 2003 Server R2 Enterprise Edition  I tried Ophcrack XP (there is no WinServer version of Ophcrack) - it couldn't locate the partitions with hashes. I tried mounting the partitions myself (#mount /dev/hda*x* /mnt/ntfs), but it gave me an error saying /dev/hda*x* didn't exist.  Next I tried booting into a Ubuntu 10.04.3 LiveCD so that I could install and use chntpw - no go, Ubuntu Live wouldn't boot.  Based on what I've read up the following tools may be of help:   Windows Password recovery Petter Nordahl-Hagen's Offline NT Password &amp; Registry Editor Openwall's John the Ripper EBCD – Emergency Boot CD - Bootable CD (R)ecovery (I)s (P)ossible Linux rescue system   I am hoping that someone here has prior experience with Win2k3 Administrator password resets so that I don't end up having to try all of the above to find out which one works. Put a where clause around a stored procedure I cannot edit recursive statistics on file types in directory? I did a website scrape for a conversion project. I'd like to do some statistics on the types of files in there -- for instance, 400 .html files, 100 .gif, etc. What's an easy way to do this? It has to be recursive.   Edit: With the script that maxschelpzig posted, I'm having some problems due to the architecture of the site I've scraped. Some of the files are of the name *.php?blah=blah&amp;foo=bar with various arguments, so it counts them all as unique. So the solution needs to consider *.php* to be all of the same type, so to speak. Drawing Mechanical Systems in LaTeX I really like CircuiTikZ for drawing diagrams in my LaTeX documents. However I mostly draw mechanical and not electronic systems, which is why I'm looking for some similar way to draw mechanical systems. What I want is something to draw masses, springs, dampers and ground (boundary condition).  are typical examples:     Anybody got some suggestions or am I out of luck? When a holomorphy ring is a PID? I will use the notation and language of Stichtenoth, Algebraic Function Fields and Codes.  Let $F$ be a function field over a finite field $\mathbb F_q$, $S$ a non empty set of places (possibly infinite) and $O_S$ the holomorphy ring of $S$, i.e., $O_S:=\bigcap_{P\in S} O_P$ (being $O_P$ the valuation ring of the place $P$).  Give necessary and sufficient conditions for $O_S$ to be a Principal Ideal Domain.  Many thanks in advance!  G. How to compact VirtualBox's VDI file size? I've a VirtualBox VM which configured a very large hard disk size (bigger than host). By my mistake, a program on the VM generated lots of log files and the VDI file size keeps growing until there is no space on the host.   Now I've deleted the log files but the VDI file size are not getting smaller after using VBoxManage.exe modifyhd "C:\Virts\mybox-i386.vdi" compact  Is there a way to really compact the VDI file size? Thanks! This option seems to have gone away after upgrading from Ubuntu 16.04. I tried installing nautilus-open-terminal but it is unable to locate the package for 18.04. Also trying to install nautilus-actions gives:  Package nautilus-actions is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source     How to fix this? Seeking documentation for {z}/{x}/{y} syntax in tilesource urls? Speaking of tilesource urls such as   http://{s}.tile.stamen.com/watercolor/{z}/{x}/{y}.png  is there any technical documentation or canonical reference for the curly braces syntax?  I'd specifically like to know what other things can be used in curly braces, and in which places, and how they work. Global and local variables in R How would you go about finding out how much memory is being used by an object? I know it is possible to find out how much is used by a block of code, but not by an instantiated object (anytime during its life), which is what I want. Is everything in the physical world composite? In philosophy there is a principle that anything composite cannot have existed eternally, since it is preceded by its parts and whatever forces assembled it.  Is everything in the physical world composite in one sense or another or is there something not composite? How can there be a directory named `~`? I was trying to test out this buggy/new tool to see how it works, and it prompted me to choose a directory to use for stuff I am doing. From the directory ~/Code/indep, I typed in ~/Code/indep/tarbell. (Stupid, I could have just typed 'tarbell', but whatever.) It prompted me to create it because it didn't exist, I said yes. When I inspected the contents of this directory, here is what I see:  brian@navis:~/Code/indep$ ls ~ project1 project2 project3 ...   I thought "oh, weird, it created a symlink to ~". However:  brian@navis:~/Code/indep$ file ./~ ./~: directory   file thinks it's a directory.   brian@navis:~/Code/indep$ ls -l drwxr-xr-x 3 brian brian 4096 Nov  8 16:50 ~ drwxr-xr-x 8 brian brian 4096 Oct 14 18:42 project1 drwxr-xr-x 3 brian brian 4096 Sep 10 21:15 project2 drwxr-xr-x 5 brian brian 4096 Oct 14 19:33 project3 ...   And so does ls -l.   I thought, "oh, ... is it a hard link? I've never really used those." But I tried to reproduce, and it's impossible to create a hard link to a directory. So... I guess I've narrowed this down to things I don't understand. Did I mount my home directory in this other directory somehow?   My main goal at this point is to remove the reference to my home directory in this folder (rm doesn't seem like the answer), but I'm also curious to know what's going on.  EDIT:   In retrospect, I understand exactly what happened. As was answered below, the program created a directory called "~" inside my current directory. The only really obfuscating fact about this is that I wasn't consistent with how I was actually viewing what the directory was. Sometimes I referred to it as  "~" and sometimes as "./~". It's only if you do the latter that you can actually see what's going on, but until I understood this, I was conflating what I was seeing from using the absolute path of "~" to to what was in fact a local directory. Patching commands to remove surrounding whitespace I'm using the todonotes package to add little margin notes to my text, however writing  Hello\todo{test} World!   removes the interword space as is already pointed out in . So I tried  \pretocmd{\todo}{\@bsphack}{}{} \apptocmd{\todo}{\@esphack}{}{}   and this adds the interword space but simply outputs all parameters instead of passing them to \todo.  Full MWE:  \documentclass{article}  \usepackage{etoolbox} \usepackage{todonotes}  \makeatletter \pretocmd{\todo}{\@bsphack}{}{} \apptocmd{\todo}{\@esphack}{}{} \makeatother  \begin{document} Hello\todo{test} World! \end{document}