Method Name:
subtract
Method Signature:
subtract(iterableObjectOrMappingObject)
Method Overview:
- subtract() subtracts the counts of elements present in an iterable object or a mapping object from the counter object.
- subtract() method returns None.
- subtract() changes the counts of elements in the counter object on which the method was called.
- If the iterable object or mapping object does not have all the elements of the counter object only the counts of common elements present in the iterable/mapping object are subtracted from the counts of counter object.
Example 1:
|
import collections
# create two boxes box1 = collections.Counter({"pen":4,"pencil":6,"eraser":3,"coins":4}) box2 = collections.Counter({"pen":2,"pencil":2,"eraser":1,"coins":2})
# subtract box2 from box1 ret = box1.subtract(box2)
#print box1 contents print(box1) |
Output:
|
Counter({'pencil': 4, 'pen': 2, 'eraser': 2, 'coins': 2}) |
Example 2:
|
import collections
# Create a counter of few alphabets and their counts c1 = collections.Counter({"a":4,"b":6,"c":3,"d":4})
# Create a tuple with few alphabets iterableObject = ("a","b")
# Subtract the counts of iterable(tuple) elements from the element counts of counter ret = c1.subtract(iterableObject)
# print the counter print(c1) |
Output:
|
Counter({'b': 5, 'd': 4, 'a': 3, 'c': 3}) |