This is a short post that explains how to write a high-performance matrix multiplication program on modern processors. In this tutorial I will use a single core of the Skylake-client CPU with AVX2, but the principles in this post also apply to other processors with different instruction sets (such as AVX512).
Matrix multiplication is a mathematical operation that defines the product of
These commands were taking from the talk Introduction to Advanced Bash Usage by James Pannacciulli
Updated 21 Jan 2017 06:54:53
FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.
| { | |
| "LAYOUTS": "----------------------", | |
| "layouts": [ | |
| "tall", | |
| "wide", | |
| "fullscreen", | |
| "column" | |
| ], | |
| "MODIFIERS": "----------------------", |
Google Chrome Developers says:
The new WOFF 2.0 Web Font compression format offers a 30% average gain over WOFF 1.0 (up to 50%+ in some cases). WOFF 2.0 is available since Chrome 36 and Opera 23.
Some examples of file size differences: WOFF vs. WOFF2
⇐ back to the gist-blog at jrw.fi
Or, 16 cool things you may not have known your stylesheets could do. I'd rather have kept it to a nice round number like 10, but they just kept coming. Sorry.
I've been using SCSS/SASS for most of my styling work since 2009, and I'm a huge fan of Compass (by the great @chriseppstein). It really helped many of us through the darkest cross-browser crap. Even though browsers are increasingly playing nice with CSS, another problem has become very topical: managing the complexity in stylesheets as our in-browser apps get larger and larger. SCSS is an indispensable tool for dealing with this.
This isn't an introduction to the language by a long shot; many things probably won't make sense unless you have some SCSS under your belt already. That said, if you're not yet comfy with the basics, check out the aweso
| Cannon.include('lib/math.js'); | |
| Cannon.include('lib/display.js'); | |
| Cannon.include('lib/misc.js'); | |
| Cannon.include('lib/SAT.js'); | |
| var canvas, cue; | |
| var shooting = false, shootStart; | |
| var rails = [], balls = [], pockets = []; | |
| var WALL_SIZE = 10, BALL_SIZE = 10, POCKET_SIZE = BALL_SIZE*1.7; |
| Latency Comparison Numbers (~2012) | |
| ---------------------------------- | |
| L1 cache reference 0.5 ns | |
| Branch mispredict 5 ns | |
| L2 cache reference 7 ns 14x L1 cache | |
| Mutex lock/unlock 25 ns | |
| Main memory reference 100 ns 20x L2 cache, 200x L1 cache | |
| Compress 1K bytes with Zippy 3,000 ns 3 us | |
| Send 1K bytes over 1 Gbps network 10,000 ns 10 us | |
| Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD |
