Background I have a 1TB portable usb hard drive which I want to host mongodb data. The OS is ubuntu 15.04 Procedure stop your mongodb service sudo service mongod stop edit `/etc/fstab` so that the computer automatically mounts your portable drive under “mongodb” user everytime the OS boots up: UUID=018483db-1b1c-4dd2-a373-58a6aa5a10be / ext4 errors=remount-ro …
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Important prerequisites: Confirm connectivity between machines you want to set as replica set Confirm the same version of Mongodb is installed on each machine. I tried one with mongo 2.6 and another with mongo 3.0 and totally failed. Then I installed mongo 3.0 on every machine. Don’t set authentication for all the machines before you …
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Tips again. This time is for Microsoft Word. 1. Ctrl+Shift+8 Show non-printing characters. You can also toggle it on manually in the menu. 2. Pay attention to the extension symbol in ribbon. It contains more options. Or you can see paragraph settings in Page Layout in ribbon: 3. Sometimes, you will find …
1. Install TexLive. This is the latex environment. https://www.tug.org/texlive/quickinstall.html We recommend to use .install-tl script to install TexLive. TexLive is usually installed at “/usr/local/texlive/year/bin/x86_64-linux/….” Although you can install vanilla TexLive via sudo apt-get install texlive, we often observe it misses advanced accessories such as fonts. 2. Install Texmaker http://www.xm1math.net/texmaker/ *** Note: On Ubuntu, Texmaker can …
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It’s been half year since last time I studied LDA (Latent Dirichlet Allocation) model. I found learning something without writing them down can be frustrating when you start to review them after some while. Sometimes it is a bit embarrassing that you feel you didn’t learn that at all. Back to the topic, this post …
This post is a collection of hypothesis test methodologies. The full collection is listed here: http://www.biostathandbook.com/testchoice.html. My post just goes over several hypothesis tests that are relevant to my research. One-way ANOVA: http://www.biostathandbook.com/onewayanova.html If you have one measurement variable and one nominal variable, and the nominal variable separates subjects into multiple groups, you want to test …
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I’ve been scratching my head for a day (06/24/2015) but it ended up that I am still baffled by the concept of Factor Analysis. So first of all, let me list what I’ve learned so far today. PCA and Factor Analysis can be deemed similar from the perspective that they are both dimension reduction technologies. …
Whether you realize or not, fcitx, a popular input method, if not properly uninstalled, can cause the notorious login loop issue on Ubuntu (i.e., every time you type your password and enter, you get asked to type your password again on the same login window). Here is the post talking about how to fully uninstall …
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http://askubuntu.com/questions/280566/my-headphones-mute-alsamixer-when-i-plug-them-in-hp-dv6-12-04 http://askubuntu.com/questions/541847/is-there-any-way-to-save-alsamixer-settings-other-than-alsactl-store The two links above are two popular links about dealing with the auto-mute problem of alsamixer. However, the two don’t help my situation. My solution 1. Type the following command: sudo alsamixer 2. Use `RightArrow` key to navigate to right until you see “auto-mute” 3. Use `UpArrow` or `DownArrow` key to set …
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Long Short Term Memory is claimed to be capable of predicting time series when there are long time lags of unknown sizes between important events. However, as to 2015.6, not many clear tutorials have been found on the Internet. I am going to list a collection of materials I came across. Probably I will write …