Starting Deep Learning Course

I met up with some of my old team from BNP Paribas last week. I found it striking that everyone who was there is now working directly with Machine Learning. It was quite inspiring!

For the last few years I’ve been building Trading Execution Algorithms for Westpac. Time to do something different!

I decided to enroll in Coursera’s Deep Learning Specialization. I’ve just finished the first week, and I am really enjoying it. Andrew Ng is a fantastic teacher. I did his previous course on Machine Learning and loved it.

Installing PostgreSQL from source on my Mac

In order to build PostgreSQL from source on my MacBook Pro running El Capitan, I first downloaded the git repo:

git clone git://

I then built it:

cd postgresql
sudo make install

This will install the binaries to the default location of “/usr/local/pgsql”.

I already had a user called “_postgres” in my /etc/passwd file, so I configured to run PostgreSQL as this user:
Continue reading “Installing PostgreSQL from source on my Mac”

Python OAuth2 failing with X509 error

I’ve just spent about 20 minutes trying to authenticate with Twitter using the Python OAuth2 module. I kept on getting an X509 error, specifically:

ssl.SSLError: [Errno 185090050] _ssl.c:343: error:0B084002:x509 certificate routines:X509_load_cert_crl_file:system lib

The solution to this is that the cacerts.txt file in the Python installation is only readable to the root user / wheel group. In order to fix that up, first find the cacerts.txt file:

find /Library/Python/ -name cacerts.txt

Then modify the permissions on the file:

sudo chmod 644 /Library/Python//2.7/site-packages/httplib2-0.7.7-py2.7.egg/httplib2/cacerts.txt

Note that the URL endpoints for twitter on the python-oauth2 Github page are currently wrong. To use the “Twitter Three-legged OAuth Example” change to, etc.

Productivity for 29th May, 2013

I coded up a script to output a chart of what my productivity looks like for the day. It is based on my Pomodoro software that logs all the time-boxes to my calendar on Mac OS/X. My program extracts all the information and constructs a nice looking chart. The idea is that I track what things are making me more productive.

You can find the script over in my GitHub repository

Pomodoro Daily Chart 2013-05-29

Renaming XCode Projects

It turns out that renaming XCode projects is easy! This StackOverflow thread showed me the trick. All you need to do is double-click slowly on the Project Name in the project hierarchy tree. This allows you to change the name. You then get a dialog showing the refactoring of everything related to the new project name.