[python] get numbers from user & print maximum and minimum (w/o using built-in function)
I'm reviewing a python exercise which does the following :

 - reads list of numbers til "done" gets
   entered. 
   
 - When "done" is inputted, **print
   largest and smallest of the
   numbers**.
   
 - And it should be **without directly
   using** the built-in functions, max()
   and min().

Here is my source.
Traceback says, "'float' object is not iterable"

I think my errors are coming from not using the list properly to calculate smallest and largest. 
Any tips and help will be greatly appreciated!


    while True:
        inp = raw_input('Enter a number: ')
        if inp == 'done' : 
            break
            
        try:
            num = float(inp)
        except:
            print 'Invalid input'
            continue                            
      
    numbers = list(num)
    minimum = None       
    maximum = None
    
    for num in numbers :                          
        if minimum == None or num < minimum :
            minimum = num
    
    for num in numbers :        
        if maximum == None or maximum < num :
            maximum = num
      
    print 'Maximum:', maximum
    print 'Minimum:', minimum

Thank you!

[python] get numbers from user & print maximum and minimum (w/o using built-in function)
===

I'm reviewing a python exercise which does the following :

 - reads list of numbers til "done" gets
   entered. 
   
 - When "done" is inputted, **print
   largest and smallest of the
   numbers**.
   
 - And it should be **without directly
   using** the built-in functions, max()
   and min().

Here is my source.
Traceback says, "'float' object is not iterable"

I think my errors are coming from not using the list properly to calculate smallest and largest. 
Any tips and help will be greatly appreciated!


    while True:
        inp = raw_input('Enter a number: ')
        if inp == 'done' : 
            break
            
        try:
            num = float(inp)
        except:
            print 'Invalid input'
            continue                            
      
    numbers = list(num)
    minimum = None       
    maximum = None
    
    for num in numbers :                          
        if minimum == None or num < minimum :
            minimum = num
    
    for num in numbers :        
        if maximum == None or maximum < num :
            maximum = num
      
    print 'Maximum:', maximum
    print 'Minimum:', minimum

Thank you!
