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I have a list of lists: [word, good freq, bad freq, change_status]
list_1 = [['good',100, 20, 0.2],['bad', 10, 0, 0.0],['change', 1, 2, 2]] I would like to delete from the list all elements which don't satisfy a condition.
So if change_status > 0.3 and bad_freq < 5 then I would like to delete that the elements corresponding to it.
So the list_1 would be modified as,
list_1 = [['good',100, 20, 0.2],['bad', 10, 0, 0.0]] How do I selective do that?
509
To remove elements from ArrayList based on a condition or predicate or filter, use removeIf() method. You can call removeIf() method on the ArrayList, with the predicate (filter) passed as argument. All the elements that satisfy the filter (predicate) will be removed from the ArrayList.
How to Remove an Element from a List Using the remove() Method in Python. To remove an element from a list using the remove() method, specify the value of that element and pass it as an argument to the method. remove() will search the list to find it and remove it.
list_1 = [['good',100, 20, 0.2],['bad', 10, 0, 0.0],['change', 1, 2, 2]] list_1 = [item for item in list_1 if item[2] >= 5 or item[3] >= 0.3] You can also use if not (item[2] < 5 and item[3] < 0.3) for the condition if you want.
104
Use the filter function with an appropriate function.
list_1 = filter(lambda x: x[3] <= 0.3 and x[2] < 5, list_1) Demo:
In [1]: list_1 = [['good',100, 20, 0.2],['bad', 10, 0, 0.0],['change', 1, 2, 2]] In [2]: filter(lambda x: x[3] <= 0.3 and x[2] < 5, list_1) Out[2]: [['bad', 10, 0, 0.0]] Note that good doesn't satisfy your condition (20 < 5 is false) even though you said so in your question!
If you have many elements you might want to use the equivalent function from itertools:
from itertools import ifilter filtered = ifilter(lambda x: x[3] <= 0.3 and x[2] < 5, list_1) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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