First Use Of The Word “Computer”

English author Richard Braithwaite in his 1613 book, The Yong Mans Gleanings, is reputed to have used the first instance of the word “computer” as describing a human who’s good at maths:

WHat art thou (O Man) and from whence hadst thou thy beginning? What matter art thou made of, that thou promisest to thy selfe length of daies: or to thy posterity continuance. I haue read the truest computer of Times, and the best Arithmetician that euer breathed, and he reduceth thy dayes into a short number: The daies of Man are threescore and ten.

where Braithwaite is describing someone who’s good at arithmetic as a “computer.”

Winifred “Tim” Asprey

When the young men joined, they became fun too. A lot of the faculty didn’t like them, but I liked them. And I loved the fact that the women stood up so brilliantly against them. The men, as I told you, had some trouble because they hadn’t been studying, but it was terribly nice to see. It worries me now that the men tend to take over the math and science.

—Professor Winifred Asprey, Vassar
Continue reading “Winifred “Tim” Asprey”

Orders of Complexity

I wish I had this table back in 1984 when I was trying to understand this stuff.

Big O Notation Name Example(s)
O(1) Constant # Odd or Even number,
# Look-up table (on average)
O(log n) Logarithmic # Finding element on sorted array with binary search
O(n) Linear # Find max element in unsorted array,
# Duplicate elements in array with Hash Map
O(n log n) Linearithmic # Sorting elements in array with merge sort
O(n2) Quadratic # Duplicate elements in array (naïve),
# Sorting array with bubble sort
O(n3) Cubic # 3 variables equation solver
O(2n) Exponential # Find all subsets
O(n!) Factorial # Find all permutations of a given set/string

and I now can firmly feel the difference between polynomial and exponential well worth this example:

n = 10 | 100 | 1000

n^2 = 100 | 10000 | 1000000

k^n = k^10 | k^100 | k^1000

Paul Baran: Distributed Networks

In 1962, U.S. authorities considered ways to communicate in the aftermath of a nuclear attack. How could any sort of “command and control network” survive? Paul Baran, a researcher at RAND, offered a solution: design a more robust communications network using “redundancy” and “digital” technology.

Rand Corp
Continue reading “Paul Baran: Distributed Networks”