City FEA:PrimaryFunctions

Jane Jacobs claimed that having multiple Primary Functions was one of her four so called Ingredients Essential to Diversity.
 * "The district, and indeed as many of its internal parts as possible, must serve more than one primary function; preferably more than two. These must insure the presence of people who go outdoors on different schedules and are in the place fordifferent purposes, but who are able to use many facilities in common." - Jacobs p.150

Discussion
Jacobs is arguing that mixed uses leads to increased diversity and health. Particularly she is saying that designating exclusively corporate, industrial or residential neighborhoods are detrimental to the health of that neighborhood.

Mathematical Form
To formalize her theory we will characterize this quality with a parameter of value between 0 and 1. For any given location this parameter will be defined as a function of the following:


 * 1) Number of daytime businesses on that block
 * 2) Need to find a measure of differing schedules