What is the difference between jackknifing and LOOCV?
Jackknife vs. LOOCV
how to reset a lost admin password? How to run both Intel and Nvidia graphics card driver on dual monitor setup? I'm trying to get Intel and Nvidia graphics card working together with two monitors. One monitor should use the Intel card and the other the Nvidia card. Of course, I want to use only one keyboard and one mouse to switch between both screens. Bumblebee didn't work for me.  I don't want to use the xserver-xorg-video-all package because I need the Nvidia card for gaming and I can't use only one graphics card because I need one for KVM virtualisation and the other one for my Linux desktop  So I tried to install the drivers and to configure the Xserver manually. The Nvidia driver is working and I get a video output. But I don't get a video output with the Intel card.  I followed   The config files: Theoretical Proof of Pauli's Exclusion Principle How to find out if an item is present in a std::vector? All I want to do is to check whether an element exists in the vector or not, so I can deal with each case.  if ( item_present )    do_this(); else    do_that(); sudo error, is mode 0777, should be 0440 I've been using the Linksys USB6300 Adapter but when I switched to Ubuntu it stopped working since its only compatible with Windows. I've tried using ndiswrapper and although it says my windows driver is installed, my device isn't showing up. Anyone know how I could get this wireless network adapter working? Thanks.  lsusb  Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 012: ID 05c6:6766 Qualcomm, Inc.  Bus 001 Device 006: ID 0bda:0153 Realtek Semiconductor Corp. Mass Storage Device Bus 001 Device 005: ID 05e3:0608 Genesys Logic, Inc. USB-2.0 4-Port HUB Bus 001 Device 004: ID 04ca:007d Lite-On Technology Corp.  Bus 001 Device 003: ID 04ca:008a Lite-On Technology Corp.  Bus 001 Device 010: ID 13b1:003f Linksys  Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Applying for a Canadian ETA after previous visits without one Why do people buy stocks that pay no dividend? Before recently, Apple Inc. did not give dividend to shareholders.  This makes me curious why people buy Apple Inc. stocks; while it might be due to the expectation of selling stocks at a higher price, this can only be possible if other people are thinking the same, thereby increasing demand. But the stocks themselves do not pay interests - so Apple's amazing revenue/profit records would not matter.... Find subexpression to minimize leafcount after replacment with temporary variable How to create 2D shadows I'd like to create lights and shadows in a 2D environment, like in the image below:    I did several searches but got no results. Do you have any hint? Recommended books for advanced undergraduate electrodynamics On my Windows machine, my main hard drive has the letter C: and the name "Local disk".   To list the drive letters in Java on Windows, the File object has the static listRoots() method. But I can't find a way to acquire the drive names (as opposed to the drive letters) on Windows.  Has anyone tried this before? Displaying and/or searching across thousands of contacts? The Need  Our application has a chat feature that allows our users to chat with other users within their database.   However, we're adding a feature that allows clients to share data between multiple databases as an "Enterprise" configuration, and we've been asked to update the design of the chat feature to allow users to chat with other users within any of those databases.   We've looked at the numbers of possible users in these scenarios, and the number of chat users in these shared database environments can be as many as 5,000.   Users need to be able find people they need to chat with out of these thousands of contacts. However, up til now, we've had a list of contacts the users can browse. Since that is a user expectation, we were hoping to still maintain a browse-able list of contacts. We have ruled out trying to display a list of 5,000 contacts, as this doesn't seem to be anywhere close to useful or usable.   We've come up with three approaches to solve the problem:  Option One  Show a list of contacts from the local database that user's can browse. Have a second tab that allows users to search the "Full Directory", returning results from multiple databases.     Pros:   Allows us to show a browse-able list of relevant contacts  Clearly indicates to users that another source of chat contacts are available   Cons:   Search would be limited to the current tab, meaning users would have to be in the right tab to return the right result Adds a possible source of user confusion: whats the difference between "contacts" and the "full directory"? Adds another tab to what should be a simple chat list     Option Two  Show a list of contacts from the user's local database, but if they search for a contact, include results from other databases as well.     Pros:   Maintains a list of contacts the user can browse Avoids adding adding another tab One search field searches all sources   Cons:   Searching a finite contact list and returning results that weren't in the contact list may defy user's mental model of how the search will work. Not clear that another source of contacts exist. May need to add explanatory text that says "Search to see contacts from the full directory".      Option Three  Add a dropdown that allows a user to select a what to search in: the local database, or the full directory.     Pros:    No additional tab required Indicates to users that another source of chat contacts are available, though not as clearly as option 1   Cons:    Search still isn't universal: the right search category must be selected to return the right result Users may not notice the dropdown or understand intuitively what its function is. May require explanatory text in search results, reminding the user they can expand the search to the full directory     Thoughts?  Right now I'm leaning towards option two, but is there another option I'm not considering here? Is there another alternative worth considering?   Thanks! $A,B,C$ are three $n\times n$ matrices such that $A$ has $n$ distinct eigenvalues, $AB=BA$, and $AC=CA$.   We need to show $BC=CB$.  Let $A$ be diagonalizable with eigenvectors say, $v_1,\dots,v_n$, so there exists $P$ such that $PAP^{-1}=D$. What more I can say from the information? Please help. When is unbalanced data really a problem in Machine Learning? Will Unity allow making custom launcher icons from .desktop files or via menu editing system? (Right now the launcher doesn't give the option to "keep in launcher" on all programs.  For some programs I use, I have to make custom launchers or .desktop files.  For instance, daily blender builds are generally just folders with an executable.  In basic Gnome or KDE, I can make a new menu entry with the menu editing system. Then, I can also add it to Docky either from the menu or by dragging a .desktop file to it. Unity launcher doesn't support drag and drop, so thats not a bug or anything, but when I open a .desktop file, it has unpredictable results. Most time it will not have "keep in launcher". Sometime it will have a pinnable item without the .desktop's icon, and if I pin the item to the launcher, it will not call upon the program again after closing it. I've also gotten it to just work with a .desktop file for celtx. What's the best way to animate an illustration for the web? I have a couple of illustrations done in Illustrator and I am planing to animate it for a website that I am working on, I've heard of  toolkit with flash, but is it the best way to go or is there another "better" way of doing it?  Here's an example of the kind of animations I am aiming for: Finding specific records of US WW2 veterans? Internal keyboard and trackpad stop working after plugging in USB device I got a new MacBook Pro with OS X Mavericks. When connecting my phone via USB, the internal keyboard and the trackpad immediately stop working -- not always but in most cases. The bluetooth mouse and an external USB keyboard are not affected. Everything else works also fine. The power button of the internal keyboard still works. Reboot helps. Any ideas? Some proof question about Fibonacci sequence