Detecting Change with Pandas
Recently, I was working with an investment management company who had an interesting problem to solve.
They had 10 years' of historical data on approximately 1500 companies. This was stored in a spreadsheet and, each month, for 10 years, they would copy the current sheet of companies, record any changes and add any new companies to the bottom. This spreadsheet had 120 worksheets - one for each month for the last 10 years - and each sheet had a at least 1000 rows - one for each company of interest at the time.
more ...Dutch Apple Pie Recipe
After visiting Amsterdam and sampling the stunningly good apple pie at Cafe Papeneiland, I had to make it myself when I returned home. There are many recipes online and, after trying them out, here's what I've settled on.
Ingredients
For the filling
- 1 kg apples, Goudrenet is the traditional dutch …
My Conference Attendance Guidelines
I regularly attend technical conferences in order to learn, make new contacts and generally participate in whatever community that conference represents.
Over the years, I have found that the best way to increase my chances of making new friends and contacts is to speak at the conference - people are far …
more ...Scouts and Facebook Groups
The views expressed in this article are my own and do not represent the views of any part of the UK Scout Association, including Mersey Weaver Scout District.
Over they last few years, many Scout Groups, Explorer Units and other parts of the Scout movement in the UK have used …
more ...Open Response to Graham Evans MP
This is an open response to a letter from Graham Evans MP, a copy of which is available on this site: http://www.owencampbell.me.uk/docs/GrahamEvansLetter.pdf
The letter was prompted by a tweet of mine which criticised his vote against an amendment to the immigration bill: https …
more ...Process
One vital role of the leader is to define and enforce the processes that the team will follow. I've seen more projects fail as result of getting this wrong than any other single cause.
Do I have the definitive answer as to the process you should follow? No, I do …
more ...Leading Technical Teams
Over the years, I've led, and been a member of, numerous technical teams on a wide variety of projects. Based on that experience, this series of articles documents my observations on the role of the leader in that sort of team.
Firstly, some thoughts on authority...
Says Who?
How did …
more ...DjAxelrod Project Sprint at DjangoCon Europe 2015
If you're at DjangoCon Europe in Cardiff next week, you should come and join in with the DjAxelrod project sprints on Thursday and Friday.
DjAxelrod is a project to build a Django based web application that will allow anyone to create Axelrod tournaments and to study their results.
But what …
more ...Rescue Project - New ERP System Implementation
The client for this project was a UK PLC with over 150 multi-national subsidiary companies.
They were replacing their ERP system for the whole Group and required full historical data migration at the transactional level - the new system should look like it had always been in place since the company …
more ...Why I use LaTeX
When I tell people that I don't use Microsoft Word, they are generally somewhat taken aback and then assume that, because I own a Mac rather than a Windows PC, that I just use Apple's Pages instead.
I don't!
In fact, I don't use any kind of conventional word processor …
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