CHAPTER 3
"PyLadies and Code Freaks"
p. 22
hence the lower prices [in Marin]: Jan, who had lived in the Bay Area before, urges me to point out that we were at the border of west Marin, acknowledging that many parts of the county, especially those closest to the Golden Gate, are far from cheap.
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a fabulously engaging tome called Python Crash Course: One of the happiest aspects of my first PyCon is that Eric Matthes and I meet and become friends, later attend a conference (reported in this book) together. I==m now in a much better position to understand just how hard it is to write books like his, and what skill it takes. Python Crash Course remains the best route into Python that I==ve come across, by far. Naomi Ceder's The Quick Python Book is also excellent, as clearly articulated and exampled reference, once you're up and running. As elsewhere, freeCodeCamp is also a great place to get a feel for the task.
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to_celsius: for comparison, what would the same function look like in JavaScript? JavaScript (JS) was designed as the web expanded in the mid-1990s, to work inside a browser. HMTL and CSS make pages that are static, where JS enables the creation of algorithms to make them active—say by offering a slideshow of images or ability to process user input in useful ways. A weather app might benefit from a Fahrenheit to Celsius converter, for instance. Examples of this basic algorithm are all over the internet and studying them provides a first window into how JS works. The first thing I learn is the centrality to programming of the function, a block of code containing a reusable algorithm that automates a chosen task. freeCodeCamp's version looks so:
| JavaScript | |
|---|---|
In JS, the guts of the algorithm are given within curly brackets, which in this case open at the end of line one and close at the start of line three, with the algorithmic work described in between. "Return" means "return the result of the following calculation," which is based on the classic formula for Fahrenheit-to-Celsius conversion—subtract 32, then multiply by five ninths. Again, the word "Fahrenheit" is a placeholder for the specific temperature we will feed the function whenever we call it. Per mathematical convention, operations contained within parentheses are carried out first, so in line two we are telling the machine, "Take the given Fahrenheit number, subtract 32 from it, then multiply the result by five ninths." In computing, an asterisk ( * ) is used to denote multiplication because the "x" symbol has other uses.
Having written the toCelsius function, we may now call it whenever we need a conversion, enclosing the temperature to be converted within the parentheses reserved for them. Output appears in the "post" window usually located below or the right of the editor screen.
toCelsius(77);
will generate output of:
25.0
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the disproportionate number of musicians in the fold: A partial thought on this. An aquaintance who happens to be trained in Indian and European classical music once explained the extraordinary system of Indian ragas to me, which consists of hundreds of complex melodic frameworks within which to compose and improvise, each with an emotional hue and resonance of its own. In the Hindu tradition ragas are considered part of the spiritual physics of existence: musicians discover rather than invent them. With such mathematical complexity woven into the fabric of everyday life, I never again wondered why India produces so many great mathematicians and physicists. And programmers? I make a mental note to chase down precisely what programmers mean by \"abstraction\" when I get home; if and how it relates to music or anything else.
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"You'll get used to it," Nicholas grins: Perhaps more iodiosyncratic was the man who sat next to me at the Great Lakes Science Center dinner the next might. He was tall and built like a mountain—clearly spent time in gyms or on special ops—and if you saw him on a sidewalk in Williamsburg you might think him stylish in Johnny Cash black, asymmetric hairdo, neat urban beard and expensive headphones . . . headphones he didn't take off through the entire course of the event—except once, to order a drink at the bar, which is how I know he could speak. Shortly after arriving, with the rest of us waiting to be invited to collect our first course from the canteen-style service, he stalked off and returned with a piece of cheesecake, presumably wrested from the hands of a bewildered server, which he ate on his own, staring into a middle distance that in truth wasn't there thanks to a wall, neither making eye contact nor uttering a single, solitary word over a space of two hours. The funny thing is you learn to enjoy these eccentricities around coders. I would feel poorer without them now.