Recent Links for 09/21/2007
Friday, September 21, 2007
Newbie - converting csv files to arrays in NumPyGreat message thread on how to convert csv files to numpy arrays. |
Cookbook/InputOutput - Numpy and ScipyFile processing examples using numpy, scipy, and matplotlib. How to read/write a numpy array from/to ascii/binary files. |
Numpy Example ListExamples of Numpy functions such as fromfile(), hsplit(), recarray(), shuffle(), sort(), split(), sqrt(), std(), tofile(), unique(), var(), vsplit(), where(), zeros(), empty(), and many more. |
Introducing Plists: An Erlang module for doing list operations in parallelCould you spawn a trading system process for each stock of a given day's trading (a list)? What if you had 20,000 stocks for a given day? Can plists/erlang handle 20,000 processes without hitting memory constraints? |
Labels: erlang, links, numpy, python
Recent Links for 09/18/2007
Tuesday, September 18, 2007
| Chapter 22. Struct and Array Modules Overview of the python struct and array modules |
Building Skills in Programming Nice python tutorial. |
| Python Grimoire Nice python cookbook. |
Labels: python
Recent Links for 09/17/2007
Monday, September 17, 2007
Labels: investing, links, numpy, python
Recent Links for 09/15/2007
Sunday, September 16, 2007
Links for 2007-09-15 [del.icio.us]
Posted: 16 Sep 2007 12:00 AM CDT
- Practical Common Lisp
Excellent way to get started with Common Lisp. - 9 Things You Simply Must Do
Friend of mine sent me this great post on Dr. Cloud's 9 principles commonly practiced by successful people. My favorites? - Principle #2: Pull the Tooth - face your fears...don't put off today what you can do today.
- Principle #4: Do Something
- ONLamp.com -- An Introduction to Erlang
Great coverage of the Erlang language. - Python Cheat Sheet
Simple little python cheat sheet.
Labels: erlang, links, lisp, python, success
Recent Links 09/05/2007
Wednesday, September 05, 2007
Speed up R, Python, and MATLAB - Going Parallel
Labels: programming, python, rlanguage
Recent Links 09/04/2007
Tuesday, September 04, 2007
World Beta - Engineering Targeted Returns and Risk: More On The Endowment Style Of Investing Annotated
- World Beta shares some links covering the endowment investing side of things...
- A link to Frontier Capital Management- check out their knowledge section for more great papers similar to the ones Faber links to.
- Faber mentions a great upcoming book covering the twelve top endowment CIO's .
- from Alpha Magazine...Highbridge Capital Managment shares its office organization - putting traders and developers together. I've always thought this would be a great idea in any shop. By putting users and developers together - manual taks can be seen and automation can happen.
- A link to
- Great little file compare utility. Graphic front end to the diff program.
note: tested this today against a large file/program (well, not that large in my line of work...but I guess to Google's)...couldn't handle it. But, works great on small files.
- post by taylortree
Google Mondrian: web-based code review and storage
- Online code review that works like a blog/wiki. I wonder...is it possible to create a code review system similar to Mondrian within a source management toolset such as subversion? Seems like most of the backend is there already...would only need to add some front end tools to display the changes being committed and allow comments on those changes.
- post by taylortree
Recent Links 09/03/2007
Monday, September 03, 2007
ONLamp.com -- Numerical Python Basics
- Numpy basics.
- post by taylortree
Finding Duplicate Elements in an Array :: Phil! Gregory Annotated
- Interesting way to find duplicates in an array. Enjoyed the links on the pigeonhold principle and Floyd's cycle-finding algorithm.
- post by taylortree
Now, suppose that the array is of length n and only contains positive
integers less than n. We can be sure (by the pigeonhole principle)
that there is at least one duplicate.
integers less than n. We can be sure (by the pigeonhole principle)
that there is at least one duplicate.
So, how do we find the beginning of the cycle? The easiest approach is to
use Floyd's cycle-finding algorithm. It works roughly like this:
Start at the beginning of the sequence. Keep track of two values (call
them ai and aj). At
each step of the algorithm, move ai one step
along the sequence, but move aj two steps. Stop
when ai = aj.
use Floyd's cycle-finding algorithm. It works roughly like this:
Start at the beginning of the sequence. Keep track of two values (call
them ai and aj). At
each step of the algorithm, move ai one step
along the sequence, but move aj two steps. Stop
when ai = aj.
Labels: programming, python
Reduce runtime of Python, R, and MATLAB applications by 85%? Process 10-100X larger datasets? With just a few code changes? Not quite sure how...but something to explore in the future. Their success story on speeding up MATLAB code for Monte Carlo Analysis looks pretty easy of a code change to me. Read their blog for further insights into HPC...
- Multicore: Why all the Hubbub?
- What is "Productivity" in High Performance Computing?
- post by taylortree