# Python function that counts negative integers using arbitrary number of parameters

Python newbie here, I need help with working with function with arbitrary number of parameters.

I want to implement a function that can take an arbitrary number of parameters, and counts negative integers. I want to try the `negative_counter` function on the following list of numbers `4,-3,5,6,-7`

See my attempt (not sure what I am doing wrong)

``````def negative_counter(*args):
# setting the negative count to 0
neg_count = 0
# iterating through the parameters
for x in args:
# negative numbers are less than 0
if args < 0:
# adding 1 to negative number
neg_count = neg_count + 1
return neg_count

# driver code
negative_counter([4,-3,5,6,-7])

#Desired output should return 2 since -3 and -7 are the negative integers
``````

Asked by: Lily345 | Posted: 30-11-2021

There are 2 problems with your code. First, it should be `if x < 0` instead of `if args < 0` because x is an element in args. Second, you have a return inside the loop, so it ends the function after increasing the `neg_count` by one.

This code may be better and shorter ;)

``````only_neg = [num for num in args if num < 0]
neg_count = len(only_neg)
``````

or

``````neg_count = sum(1 for i in args if i < 0)
``````

Answered by: Vivian480 | Posted: 01-01-2022

There are a couple issues with your code:

• You've specified that the function take a single variadic argument, as discussed in the Arbitrary Arguments List documentation. So, `args` ends up being a list with one element, the list you're passing in your driver.
• You need to perform a comparison against `x` instead of `args`.

Here are examples that show demonstrate working with variadic arguments as well as unpacking argument lists, along with a simplified implementation:

``````def negative_counter(*args):
neg_count = 0
for x in args:
if x < 0:
neg_count = neg_count + 1
return neg_count

def negative_counter_list(num_list):
neg_count = 0
for x in num_list:
if x < 0:
neg_count = neg_count + 1
return neg_count

def negative_counter_simplified(*args):
return len([x for x in args if x < 0])

numbers = [4, -3, 5, 6, -7]

# use "*numbers" to unpack the list
print(negative_counter(*numbers))

# use the function that actually expects the list
print(negative_counter_list(numbers))

# use the simplified implementation, once again unpacking the list
print(negative_counter_simplified(*numbers)
``````

Output:

``````\$ python3 test.py
2
2
2
``````

Answered by: Aldus729 | Posted: 01-01-2022

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