Python: INTRO

• intuitive
• dynamic
• easy to get started
• little/no boilerplate
• "batteries included"
• consistent
• simple tools

#include >stdio.h<
  int main(int argc, char** argv)
  {
    printf("Hello World");
    return 0;
  }

class HelloWorldApp {
  public static void main(String[] args) {
    System.out.println("Hello World!"); // Display the string.
    }
  }

 print('hello world!')

# string / text
"im a string!"
# int / number
24
# float / number with decimal
24.4
# list / a list of somethings (numbers etc)
[12, 14, 4, 524, 5, -240, 50] or ["asdf", "52jgar", "afwefw4"]
# dict / a list of something to something 
{'city': 'la', 'state': 'california'}
# function 
help() # does something

#  Try entering a few strings in your console!
#  type print("im a string!") to print a string to the screen?

{'number_of_people_here': 50, 'number_of_people_paying_attention': 20}vs number_of_people_here = 50number_of_people_paying_attention = 20number_of_people_not_paying_attention = number_of_people_here - number_of_people_paying_attentionvspeople_count = 50people_showing_attention = 20people_not_showing_attention = people_count - people_showing_attention

int(10.0) <- force integerfloat(10) <- force floatstr(10) <- force string
(int)10.0 

def imafunction():
  print 'hi world!'

imafunction()
# calls the function imafunction
# prints hi world.

def add(num1, num2):
    return num1 + num2
def max(num1, num2):
    if (num1 > num2):
        return num1
    else:
        return num2
def min(num1, num2):
    if (num1 < num2):
        return num1
    else:
        return num2
def sub(num1, num2):
    return num1 - num2
def lowest_diff(num1, num2):
    return sub(max(num1, num2), min(num1, num2))
print lowest_diff(20, 90)

import random
# random from 10 to 100
print random.randrange(10, 100)
# random from 0 - 1
print random.random() 

words = ['this', 'makes', 'sentence', 'sense', 'what']
print words
random.shuffle(words)
print words

if (temperature > 50):
    print "it's hot!"

def analyze_temperature(temperature):
    if (temperature > 80):
        print "it's hot!"
    elif (temperature < 60):
        print "it's cold!"
    else:
        print "nice in ca!"
    
analyze_temperature(int(raw_input('What temperature is it?')))
    

python print_the_weather.pyit's a nice ca day!bye!

# file: print_weather_now.py
location = find_my_location()
weather = download_weather_now()
temp = weather.temperature
analyst_string = analyze_temperature(temp)
print 'It's %i today, %s' % (temp, anaylst_string)
print 'bye!'

import antigravity

• imports let you import libraries, functions of collections that can do exciting things easily.
  
• you can install your own libraries, and use the ones included as well
  
• the best way to install new libraries is to use the `pip` tool included with most pythons.
  
• if you don't have pip, use easy_install to install pip `sudo easy_install pip` 
  
• then you're on your way!
  

import urllib2
import json
req = urllib2.urlopen('http://freegeoip.net/json/')
req_str = req.read()
req_json = json.loads(req_str)
my_zip = req_json['zipcode']
print 'Your zipcode is ' + my_zip + ' in ' + req_json['city'] + ' ' + req_json['region_name'] + '.'
# or:
print('Your zipcode is %s in %s %s' % (my_zip, req_json['city'], req_json['region_name']))    

import urllib2
import json

def get_location():
    req = urllib2.urlopen('http://freegeoip.net/json/')
    req_str = req.read()
    return json.loads(req_str)

def get_todays_weather(coords):
    req = urllib2.urlopen('http://api.openweathermap.org/data/2.5/weather?lat=%s&lon=%s' % (coords['latitude'], coords['longitude']))
    req_weather_str = req.read()
    weather_data = json.loads(req_weather_str)
    return weather_data

def convert_to_farenheit(kelvin):
   #(ºK- 273.15)* 1.8000 + 32.00
   return (float(kelvin) - 273.15) * 1.8000 + 32.00

def analyze_weather(temp): print "It's %.2f today" % temp

todays_weather = get_todays_weather(get_location())
temp_in_kelvin = todays_weather['main']['temp']
weather_anaylsis = analyze_weather(convert_to_farenheit(temp_in_kelvin))