Equivalent of pandas .append() method, which allows method chaining Question: Now that append() is removed in pandas 2.0, what is a short alternative to append() allowing method chaining? The "What’s new in 2.0.0" section of pandas says: Removed deprecated Series.append(), DataFrame.append(), use concat() instead (GH 35407) I am looking for something like below to add …
How to method-chain `ffill(axis=1)` in a dataframe Question: I would like to fill column b of a dataframe with values from a in case b is nan, and I would like to do it in a method chain, but I cannot figure out how to do this. The following works import numpy as np import …
Can I use method chaining to delete rows with a if-else condition? Question: Right now my df looks like this (I shorten it cause there are 20 rows). import pandas as pd df=pd.DataFrame({‘Country’: ["Uruguay", "Italy", "France"], ‘Winner’: ["Uruguay", "Italy", "France"]}) def f(row): if row[‘Country’] in row[‘Winner’]: val = False else: val = True return val …
How to chain Python's set.add() while updating dictionary values being sets? Question: Let’s create dictionary dctD entries with values being set()s: dctD = {‘key0’:set([‘value0’])} # static constant (key, value) pair dctD[‘key1’] = set([‘value1’]) # static constant (key, value) pair Now the dictionary has to be updated with a new value which should extend its set() …
Python: PyCharm IDE method chaining suggestions not working when using decorators Question: Given below code: def method_friendly_decorator(method_to_decorate): def wrapper(self, *args, **kwargs): print(‘I got args! Look:’.join(*args, **kwargs)) method_to_decorate(self, *args, **kwargs) return self return wrapper class DecorateMe(object): def __init__(self): self.first_name: str = ” self.last_name: str = ” @method_friendly_decorator def print_first_name(self, first_name: str): self.first_name = first_name print(f’My first …
Pandas – using assign and if-else statement in method chaining Question: I come from an R background and I’m trying to replicate the mutate() function from dplyr in pandas. I have a dataframe that looks like this: data = {‘name’: [‘Jason’, ‘Molly’, ‘Tina’, ‘Jake’, ‘Amy’], ‘age’: [42, 52, 36, 24, 73], ‘preTestScore’: [4, 24, 31, …
Basic method chaining Question: I found this method chaining in python, but even with it I couldn’t understand method chaining in Python. Here the goals are two: solve the coding problem and understand method chaining (given that I am still not 100% confident with callables). Down to the problem definition. I want a class that …
Is there a query method or similar for pandas Series (pandas.Series.query())? Question: The pandas.DataFrame.query() method is of great usage for (pre/post)-filtering data when loading or plotting. It comes particularly handy for method chaining. I find myself often wanting to apply the same logic to a pandas.Series, e.g. after having done a method such as df.value_counts …
Return self in python Question: I have a class that represents object. And I have a bunch of methods which modify this object state with no obvious return or obviously without any return. In C# I would declare all these methods as void and see no alternatives. But in Python I am about to make …
method chaining in python Question: (not to be confused with itertools.chain) I was reading the following: http://en.wikipedia.org/wiki/Method_chaining My question is: what is the best way to implement method chaining in python? Here is my attempt: class chain(): def __init__(self, my_object): self.o = my_object def __getattr__(self, attr): x = getattr(self.o, attr) if hasattr(x, ‘__call__’): method = …
