How to install Scala from the official Scala distribution? This is needed on a Linux release with older version of Scala in the repository, e.g. Fedora 12. Use the install-scala.sh script: # wget https://raw2.github.com/zma/usefulscripts/master/script/install-scala.sh # sh ./install-scala.sh VER where VER is the scala version that you want to install. First step, install and configure the…
This tutorial introduces how to install Scala 2.9.2 on 64-bit Fedora Linux 17. There are some changes needed to make scala work on Fedora Linux 17. Please check it out in the answer. Install Java Scala depends on Java, so please install Java first. In this tutorial, we installed JDK to: /usr/java/jdk1.6.0_24/lib/. Install Scala from…
This tutorial introduces how to exclude certain repositories in yum. Excluding certain repositories is needed usually. One example may be when you have several repositories that have the same package and you only want the one from a certain repository. For my situation, I choose to exclude the google-chrome and other repositories from Google when…
How to get the native assembly code (e.g. x86-64 asm) for OCaml code generated by the native ocamlopt compiler? To get the assembly code for an OCaml program, add these parameters to ocamlopt: -S -inline 20 -nodynlink An example is as follows. The OCaml program: $ cat not.ml let not x = ((x – 1)…
This is a tutorial on “how to delete all topics and posts from a user/spammer in myBB”. Please check out the answer. I use the Goodbye Spammer plugin for MyBB. First, install it after downloading the plugin form its homepage: Upload ./inc/plugins/goodbyespammer.php to ./inc/plugins/ Upload ./inc/languages/english/goodbyespammer.lang.php to ./inc/languages/english/ Go to ACP > Plugins > Activate…
There is a “Include full text in feeds:” option in the “RSS feeds” configuration panel but no options/method to only show excerpt instead of the “full text” or nothing for RSS feeds. This need to hack the question2answer source code. Details are in the answer. The changes based on Question2asnwer 1.5.4: diff –git a/qa-include/qa-index.php b/qa-include/qa-index.php…
After a server crash and restarting, MyBB reports a SQL Error as follows: MyBB SQL Error MyBB has experienced an internal SQL error and cannot continue. SQL Error: 145 – Table ‘./mybb/mybb_sessions’ is marked as crashed and should be repaired Query: SELECT * FROM mybb_sessions WHERE sid=’40021925bd0494ea31…’ AND ip=’x.x.x.x’ LIMIT 1 The dababase is MySQL….
How to save a Word document to be a PDF in Office 2007? I find this add-on for Office 2007 from Microsoft: 2007 Microsoft Office Add-in: Microsoft Save as PDF or XPS. It works very well for me. After installing this plugin, I can open a Word document and save it as a PDF file.
How to use OCaml as a script language like bash and python? It will be good that I can write a script in OCaml and directly invoke it. For example, I write a script named “script.ml” and then I can invoke it directly by $ ./script.ml Thanks! Three helloworld scripts: script3.ml #! /usr/bin/env ocaml print_string…
I can list all local branches by git branch How to list a git repository’s all branches on the remote server? You need the -r option: git branch -r From the man page of git-branch. -r List or delete (if used with -d) the remote-tracking branches.
After setting the font sizes for Gnuplot, they fonts look good. However, the y labels is too far away from the y-axis. How to change the position of y-axis label in Gnuplot? You can make use of the {offset <offset>} option. For example: set ylabel “Y Label” offset 3,0,0 which moves the ylabel 3 characters…
I backup my iPhone with iTune to my local computer. Where can I find out the backup files of my iPhone by iTune? And how to get the real files (like songs, notes, etc.) from the backup files? The location of the backup files from iTune It depends on the computer’s operating system: Mac: ~/Library/Application…
How to efficiently print a webpage? E.g. I want to only print the text for some pages but with figures for some other pages. I tried to copy the webpage to a document, but the format turns to be just terrible. One good tool that I use is PrinterFriendly which can convert a webpage to…
Grub2: How to boot Fedora to an old kernel? The old kernel is a submenu under “Advanced options for Fedora”. It is not shown if I follow the instruction that # grep menuentry /boot/grub2/grub.cfg | cut -d “‘” -f2. The old kernel in grub2 is in a submenu entry in a menu. The key is…
How to set Chrome RSS Subscription Extension so that I can subscribe to RSS feed using Feedly? Both tools are great and it will be better to combine them together. The link in feedly to subscribe a RSS feed (e.g. https://www.systutorials.com/b/feed/ ) is: http://www.feedly.com/home#subscription/feed/https://www.systutorials.com/b/feed/ We can replace the RSS feed URL with a %s in…
How to change the font sizes of labels (x and y axis) and keys for Gnuplot? The default fonts turn to be too small when I shrink the images in my paper. Several methods are available for Gnuplot: Set the global fonts size for the terminal: set terminal enhanced font ‘Verdana,10’ Here, 10 is the…
Which tools to mange OCaml packages in my system (Linux)? I use OPAM to manage OCaml packages: http://opam.ocamlpro.com/index.html To install it: $ wget https://raw.githubusercontent.com/ocaml/opam/master/shell/opam_installer.sh $ sh ./opam_installer.sh /usr/local/bin More options are available here. To make opam settings take effect, append this to ~/.bashrc: eval `opam config env` Some frequent usages: opam list # List all…
I frequently hear that cin is significantly slower than scanf in C++. Is this true? And how to improve the efficiency of cin? It is really nice to use most of time. One discussion about that cin is very slow is here: http://apps.topcoder.com/forums/?module=Thread&threadID=508058&start=0&mc=7 In short: cin is not always slower (can be faster actually, see…
How to import a source file to OCaml’s toplevel? Say, I want to use a function implemented in a source file in the toplevel. #use “file-name”;; Read, compile and execute source phrases from the given file. This is textual inclusion: phrases are processed just as if they were typed on standard input. The reading of…
I am writing a OCaml program but want to call some C functions provided in some source code or library. How to achieve this? Is there any good tutorials on this? A very good tutorial that is easy to follow and understand: How to wrap C functions to OCaml. A comprehensive reference manual: Chapter 19…