[Tutor] selecting elements from a list that do not meet selection criteria

[Kent Johnson]

ted b wrote:
> Is there a way i can select all elements from a list
> that do not meet selection criteria. I want to be able
> to select elements that have values of, say, < 1 but
> only if at least one of the elements has a value of >
> 0.

I'm not sure if you mean > 0 or >1, you seem to say both at different times.

> I don't want to just use something like "if x.value()
> != 0" or "if x.value() < 1" since those would give
> results if all elements were less than 1, and i only
> want to select elements of the list that are less than
> 1 if at least one of the elements is > 1.

Use any():
   if any(x.value() > 0 for x in a):
     for x in a:
      if x.value() > 0:
        print x
        x.otherStuff()

> Here's the sample code:
> 
> class One:
>    def value(self):
>       return 0

BTW this style of programming - using getter methods to access values - 
is not idiomatic Python. Better would be to use a value attribute directly:

class One:
   def __init__(self):
     self.value = 0

Then refer to One().value instead of One().value()

Kent