Bejegyzések

Bejegyzések megjelenítése ebből a hónapból: július, 2016

CUDA accelerated linear algebra with Python and Theano

Theano is a Python module that enables one to construct mathematical expressions with matrices and/or tensors (basically more than 2 dimensional "matrices"). These expressions are than can be evaluated using Python, but Theano can translate the expression into a C program and compile it to binary. This way it can achieve respectable performance. But wait, there's more! Theano can build the program so certain - or all - parts of it run on a GPU. Yes, on your video card. Modern cards can do calculations in a way that makes them especially fit for doing linear algebra and similar operations. In "similar" I mean the execution of simple operation on lots of data in parallel. A GPU-s can be several (tens or hundreds of) times better, than your CPU. I'm going to show you how to exploit an NVIDIA GPU, using Python.

Building a radiation detector from scratch 2 - the first detector

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The detector will consist of a tin can, two transistors and a DVM. I will also show how to improve and stabilize the basic circuit by adding an extra transistor and an identical "dummy" circuit to cancel leakage current and temperature dependence.

Musings on the ADIF file format

The ADIF file format is a simple way to store and organize Amateur Radio (or HAM Radio) log data. It is a way amateur radio operators most frequently store their records on the contacts they make (probably after paper). (For fellow HAMs, my callsign is HA5FTL, see my QRZ.com page for a description of my station and yours truly, and for contact information, if you wish to express your objections and/or approval of one or several of my points made in this article.) I have to start with a disclaimer.