Spectral graph theory

Spectral graph theory

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Transfer learning for collective link prediction

Transfer learningforclp

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Compressing and Decompressing Files

To decompress tar.gz (tgz) do (tar combines multiple files in a directory to a single file and gz compresses it)

• tar xzvf filename

To compress to tar.gz do

• tar czvf filename.tgz directory/

To decompress bz2 files do

• bunzip2 filename.bz2
• if it is tar.bz2 then do tar -xjvf filename.tar.bz2

To compress into tar.bz2 do

• tar cjvf filename.tar.bz2 directory/

How to link external libraries in C/C++

If you want to link /usr/local/lib/liblbfgs.so and compile quadratic.cpp then you have several options.
(include libbfgs.h in quadratic.cpp first)
g++  -Wall quadratic.cpp /usr/local/lib/liblbfgs.so -o quadratic

Or if this library is on your LD_LIBRARY_PATH, then you can simply do the following
g++ -Wall quadratic -llbfgs -o quadratic

Flusing output in Python

When you use "print" statement to output messages to terminal during the execution of a python program, those messages might not get outputted promptly. This is true for time consuming programs that perform a lot of work in between print statements. To promptly flush the text to terminal invoke the python interpreter with "-u" option. For example, if your program is myprogram.py then do the following.

python -u myprogram.py

Alternatively, if you are using sys.stdout.write to print messages to the terminal, then you can do sys.stdout.flush() right after the sys.stdout.write() to do the same. This works even with file I/O.
file.flush() immediately writes the text that is in buffer. This is particularly useful when you are writing log files.

emacs useful commands

Here are some useful tips from this site.

1. C-s incremental search. Once you have reached the end of the buffer it will perform an overlap search from the start.
2. Use fn+left arrow to move to the end of the current line.
3. Use fn+right arrow to move to the start of the current line.
4. Use fn+up arrow to move to the start of the buffer.
5. Use fn+down arrow to move to the end of the buffer. (These are tested on Aquamacs)
6. M-x grep is extremely useful. It will bring the grep -n -e command to which you must append the filename and the 'string to match' and hit return. The grepped results will be shown in a separate buffer which you can click to move to the appropriate position in the source file.
7. M-x shell opens a remote/local shell on a separate buffer.
8. If a file is in version control then emacs shows that in the bottom buffer bar. (e.g. SVN).
9. C-x v = shows the modifications that you have done since the last commit to the current file.
10. C-x v v will perform the next appropriate version control action to the current file. If it is a commit then you will get a buffer to write a commit note and then hit C-c C-c to make the commit.
11. To enter/exit from full screen mode use: command+shift and return.

bash script to convert encoding of all files in a directory

The following bash script calls iconv on each text file in the input directory and converts them from shift-jis (sjis) to Unicode UTF-8 (utf-8).


#! /bin/bash

inputDir="danu-summaries"
outputDir="danu"

for file in ../$inputDir/*; do
    if [ -f $file ]; then
fname=`echo "$file" | cut -d '/' -f3`
echo $fname
iconv -f sjis -t utf-8 ../$inputDir/$fname > ./$outputDir/$fname
    fi
done