Notes 9/23/13

In [1]:

    

name = raw_input("What's your name? ")
print "Hello", name


    

    




What's your name? ted
Hello ted

In [5]:

    

age = raw_input("How old are you? ")
print float(age)


    

    




How old are you? 5
5.0

In [6]:

    

import math
def area(radius):
    return math.pi * radius**2

print area(5)


    

    




78.5398163397

In [7]:

    

def test2():
    print "hey"
    return

def echo(something):
    return something
    
def bad():
    return echo


    

In [9]:

    

def distance(x1, y1, x2, y2):
    return 0.0

distance(5,6,7,8)


    

    
Out[9]:





0.0

In [10]:

    

def distance(x1, y1, x2, y2):
    dx = x2 - x1
    dy = y2 - y1
    print 'dx is', dx
    print 'dy is', dy
    return 0.0

distance(5,6,7,8)


    

    




dx is 2
dy is 2






    
Out[10]:





0.0

In [11]:

    

def distance(x1, y1, x2, y2):
    dx = x2 - x1
    dy = y2 - y1
    dsquared = dx**2 + dy**2
    print 'dsquared is: ', dsquared
    return 0.0
distance(5,6,7,8)


    

    




dsquared is:  8






    
Out[11]:





0.0

In [13]:

    

import math
def distance(x1, y1, x2, y2):
    dx = x2 - x1
    dy = y2 - y1
    dsquared = dx**2 + dy**2
    result = math.sqrt(dsquared)
    return result
distance(1,4,17,19)


    

    
Out[13]:





21.93171219946131

In [14]:

    

def factorial(n):
    space = ' ' * (4 * n)
    print space, 'factorial', n
    if n == 0:
        print space, 'returning 1'
        return 1
    else:
        recurse = factorial(n-1)
        result = n * recurse
        print space, 'returning', result
        return result
factorial(6)


    

    




                         factorial 6
                     factorial 5
                 factorial 4
             factorial 3
         factorial 2
     factorial 1
 factorial 0
 returning 1
     returning 1
         returning 2
             returning 6
                 returning 24
                     returning 120
                         returning 720






    
Out[14]:





720