How to use Scrapy to scrape and save to sqlite

I am currently working on a project, which needs some backpack images and information. After spending some time googling, I found a handy tool called Scrapy--a python module which helps me crawl easily and neatly. In this post, I want to write down how I implemented this. Since I am a newbie in Scrapy, … Continue reading How to use Scrapy to scrape and save to sqlite

How to create a progressbar in Django

In my latest project, I created a Django website and use it to process long tasks for users, a problem is that the process time is loooong and we need a progress bar so that the users won't think the website is dead or so. After some googling, I found [Celery](, which is an asynchronous task queue/job queue based on distributed message passing. Thus, I was able to achieve these functionalities for my website:

Using Computation Graph to Understand and Implement Backpropagation

Recently, by hacking on Assignment2 of the awesome open class [cs231n](, I finally stop bumping my head to the wall every time I came across backpropagation, now I even feel a little bit enjoy when hacking the backpropagation process! In this post, I will show how to use computation graph to implement both forward and backward process of Batch Normalization, Convolution and Pooling.