Post tagged: algorithm

128-bits multiply with NumPy

128-bits multiply

For another on-going project, I needed to do 64-bits x 64-bits to 128-bits multiply, and I needed it in Python. When doing numerical work with Python, I always use NumPy which is a really awesome library. Unfortunately NumPy is heavily biased towards hardware native types, which makes sense …

Amazon Interview Coding Challenge

My Amazon interview

Quite some time ago, I was contacted by Amazon for a position in the AWS DNS team. I was curious to hear more about it and agreed to enter their recruitment process. The 1st step was a coding challenge.

In this post I will described the challenge …

Non-square matrix in-place transpose

Saving memory through in-place transpose

I recently came across an interesting problem at work: how to efficiently transpose a non-square matrix in-place?

One of my colleague is working on optimizing a six-steps FFT on our manycore processor, the MPPA-256. The six-steps FFT algorithm has a lot of nice properties, especially …