The First Cry of Atom Today is the first day of the rest of my life.

Welcome to Jekyll!

I updated the site powered by Jekyll from Octopress. Hello Jekyll! Read more

Remind for INSERT INTO with psycopg2

The most famous library to connect PostgreSQL from Python might be psycopg2. psycopg2 is a simple and easy to use library for who want to manipulate SQL simply. When I want to put a record into a table, I wrote a query like this. conn = psycopg2.connect(host=pg_credential.hostname, port=pg_credential.port, ... Read more

Deleting unused files in Chef cookbook

When you use Chef cookbook, a lot of files might be installed in you machine, configuration, script and so on. Chef provides very useful resource for putting a file called template. You can put any type of text file with this resource. Template Resource But template does not manage a file when it is unused. How can we delete a file once instal... Read more

Optimization for neural network

The other day I read this article. This post was written about the variation of gradient descent algorithm. Gradient descent is an de facto standard algorithm for optimizing deep learning. Iterative optimization algorithm such as gradient descent plays an important role in deep learning because there is no way to find the global solution analyti... Read more

Spark in Production

Finally the book I wrote at the first time in my life has been published today. It is the first chance to write a published book written on paper. I’m amazed at the fact that I can complete to write a book in English though I’m not an native English speaker. Of course it is not totally owe to myself. I cannot say thank you enough to editors and ... Read more