define

[Anton Muhin]

Turhan Ozen wrote:
> in c it is possible to define
> 
> #define PH x[1]
> 
> so PH = 3 means x[1]=3
> 
> how can I do this in python?
> 

Although quite agree with all the previous posters that you shouldn't do 
it (even in C++ there is a better way: something like float &ref = 
x[1]). However, if you are deadly sure what are you doing you can use 
something like above:

 >>> class ListRef:
... 	def __init__(self, l, ind):
... 		self.__list = l
... 		self.__ind = ind
... 	def set(self, val):
... 		self.__list[self.__ind] = val
... 	def get(self):
... 		return self.__list[self.__ind]
...
 >>> lr = ListRef(l, 0)
 >>> lr.get()
3
 >>> l
[3, 5, 5, 5, 5]
 >>> lr.set(5)
 >>> l
[5, 5, 5, 5, 5]
 >>> lr.set(7)
 >>> l
[7, 5, 5, 5, 5]
 >>>

hth,
anton.