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Lists & loops

Iterate, transform, and combine sequences with readable loop patterns.

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Lists & loops easy

Replace Negative Values in a List with Python

This code defines a function that replaces every negative number in a list with a replacement value, defaulting to zero, using a list comprehension.

list-comprehension data-cleaning list-transformation
Python 
def replace_if_negative(values, replacement=0):
    return [replacement if value < 0 else value for value in values]

if __name__ == "__main__":
    numbers = [5, -3, 8, -1, 0, -7, 2]
    result = replace_if_negative(numbers)
    print(f"Original: {numbers}")
    print(f"Replaced: {result}")
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