How to get the empty list?

[psbasha]

Hi,

I would like to clear /delete all the list data.How to procees without assigning empty data.Is there any method available?.

Say:

list1 = [1,2,3]

I dont want to do list1 =[]

-PSB

[psbasha]

Hi ,

Below is the sample code,where I am expecting the list should return empty [],but it is returning the [1,2].

Whether " listData = []" is taking in function Func1() as local variable because of the declaration.

How to overcome this issue?

Sample
 
def Func1(Flag,listData):
    if Flag:
        listData = []
    else:
        listData.append(1)
        listData.append(2)
 
 
if __name__ == '__main__':
 
    listData = []
    Func1(True,listData)
 
    Func1(False,listData)
 
    Func1(True,listData)
 
    print listData 
 
>>> [1, 2]
 
 

-PSB

[ilikepython]

Hi ,

Below is the sample code,where I am expecting the list should return empty [],but it is returning the [1,2].

Whether " listData = []" is taking in function Func1() as local variable because of the declaration.

How to overcome this issue?

Sample
 
def Func1(Flag,listData):
    if Flag:
        listData = []
    else:
        listData.append(1)
        listData.append(2)
 
 
if __name__ == '__main__':
 
    listData = []
    Func1(True,listData)
 
    Func1(False,listData)
 
    Func1(True,listData)
 
    print listData 
 
>>> [1, 2]
 
 

-PSB

Well you can have the function return a value. LIke this:

def func1(Flag, listData):        //can also work w/o second arguement
    if Flag:                             
        listData = []
        return listData
    else:
        listData.append(1)
        listData.append(2)
        return listData
 

Not sure if that's the best way though.

[psbasha]

This is a sample piece of code.But I have some more statements to be executed.I cannot return the values.

-PSB

[psbasha]

But in this case call by reference approach is broken.How to handle this situation?

-PSB

[bartonc]

This is a sample piece of code.But I have some more statements to be executed.I cannot return the values.

-PSB

>>> aList = [1, 2, 3]
>>> del aList[:]
>>> aList
[]
>>>

[bartonc]

Hi,

I would like to clear /delete all the list data.How to procees without assigning empty data.Is there any method available?.

Say:

list1 = [1,2,3]

I dont want to do list1 =[]

-PSB

see below -- try not to double post you questions.

Thanks.

[psbasha]

Hi Barton,

Thanks for the solution.It really helped me.I was trying to do the code modularity,where for some reason in my code ,I need to assign the empty list , .

I almost spend more time by trying to get the solution,finally I thought I will post in the forum.

Thanks once again Barton

PSB

[bartonc]

Hi Barton,

Thanks for the solution.It really helped me.I was trying to do the code modularity,where for some reason in my code ,I need to assign the empty list , .

I almost spend more time by trying to get the solution,finally I thought I will post in the forum.

Thanks once again Barton

PSB

That's what we're here for. You are welcome.