Friday, September 18, 2009

Auntie Em gets vertigo:

David has just taken delivery of a 1TB drive at work. We wondered how long it would take to read a TB disk full of (uncompressed ascii) text. Here are our back-of-the-envelope calculations:

1TB =
10^12 bytes =
8 * 10^12 bits =
1.14 * 10 ^12 characters [1] =
1.9 * 10^11 words [2] =
950,000,000 minutes[3] =
1,806.22 years [4]

[1] Assume 7 bits per ascii character (using the basic subset of 128 7 bit characters)
[2] Assume an average of 6 characters per word
[3] Assume a 200 wpm reading speed
[4] That's reading 24*7*364.25 But give yourself an 18 minute break to account for the accumulated leap seconds

As of May '09, the US Library of Congress has accumulated 100 TB of data. I'm assuming that's not all ascii text though

Thursday, September 03, 2009

Just had my mind blown...

by this passage in Numbers are associated with different types of spatial information depending on the task van Dijck, Gevers and Fiasa

"When patients neglecting the left side of perceptual space bisect physical lines, they typically shift the subjective midpoint towards the right. Similarly, when indicating the midpoint of a numerical interval (e.g. what is in the middle between 1 and 9?) they overestimate the midpoint (e.g. 7)."

(Emphasis mine!)