Notes on codes, projects and everything
To test our understanding in RSA public key cryptosystem, we were being asked to develop a computer program to demonstrate the cryptosystem. The whole system consists of a random number generator, an encoding module that is able to encode characters into numbers, an encryption module as well as decryption module and finally an RSA cryptosystem cracking module.
The program is written in Microsoft® Visual C6, the reason why Visual C6 is being selected is because we wanted to do something simple. There is no GUI being implemented as we wanted to spend more time in enhancing the program.
To generate random number, we used Blum-Blum-Shub random number generator as we found it to be the easiest to implement.
I happened to find a general solution suggestion on a Wikipedia entry when I was browsing the internet around to find a solution to modular exponential problem. The code snippet posted on the wikipedia entry claimed that it came from …
RSA is a cryptosystem …
Implementing RSA with Visual C
array_map function is a function that I use the most in my php scripts recently. However, there are times where I want to pass some non-array into it, therefore often times I have code like the snippet shown below:
$result = array_map(
'some_callback',
array_fill(0, count($some_array), 'some_string'),
array_fill(0, count($some_array), 'some_other_string'),
$some_array
)
It doesn’t look good IMO, as it makes the code looks complicated. Hence, after seeing how the code may vary in all different scenarios, I created some functions to clean up the array_map call as seen above. Code snippet after the jump
I was thinking whether it is possible to avoid exposing PDO and PDOStatement objects to the users of my database library (mainly just me). While I was working on my project I sort of notice that there is a almost fixed pattern whenever I work with the database. With this in mind, I added in some new functions to the library, and decided to make a quick release for this.
Just happened to see this post a few months ago, and the author created another cloud that uses almost the same technique to ‘visualize’ a list of countries. The author uses PHP to generate the cloud originally and I thought I may be able to do in javascript. After some quick coding I managed to produce something similar to the first example, source code after the jump.
While working on a text classification task, I spent quite some time preparing the training set for a given document collection. The project is supposed to be a pure golang implementation, so after some quick searching I found some libraries that are either a wrapper to libsvm, or a re-implementation. So I happily started to prepare my training set in the libsvm format.
With most of my stuff more or less set, I guess it is time to start documenting the steps before I forget. So I heard a lot of good things about docker for quite some time, but haven’t really have the time to do it due to laziness (plus my relatively n00b-ness in the field of dev-ops). Just a few months ago, I decided to finally migrate away from webfaction (thanks for all the superb support) to a VPS so I can run more things on it.