Python | Pandas Series.select ()
Серия Pandas - это одномерный массив ndarray с метками осей. Этикетки не обязательно должны быть уникальными, но должны быть хешируемого типа. Объект поддерживает индексирование как на основе целых чисел, так и на основе меток и предоставляет множество методов для выполнения операций, связанных с индексом.
Pandas Series.select()
function return data corresponding to axis labels matching criteria. We pass the name of the function as an argument to this function which is applied on all the index labels. The index labels satisfying the criteria are selected.
Syntax: Series.select(crit, axis=0)
Parameter :
crit : called on each index (label). Should return True or False
axis : int valueReturns : selection : same type as caller
Example #1: Use Series.select()
function to select the names of all those cities from the given Series object for which it’s index labels has even ending.
# importing pandas as pd import pandas as pd # Creating the Series sr = pd.Series([ "New York" , "Chicago" , "Toronto" , "Lisbon" , "Rio" , "Moscow" ]) # Create the Datetime Index index_ = [ "City 1" , "City 2" , "City 3" , "City 4" , "City 5" , "City 6" ] # set the index sr.index = index_ # Print the series print (sr) |
Выход :
Now we will use Series.select()
function to select the names of all those cities, whose index label ends with even integer value.
# Define a function to Select those cities whose index # label"s last character is an even integer def city_even(city): # if last character is even if int (city[ - 1 ]) % 2 = = 0 : return True else : return False # Call the function and select the values selected_cities = sr.select(city_even, axis = 0 ) # Print the returned Series object print (selected_cities) |
Выход :
As we can see in the output, the Series.select()
function has successfully returned all those cities which satisfies the given criteria.
Example #2: Use Series.select()
function to select the sales of the ‘Coca Cola’ and ‘Sprite’ from the given Series object.
Выход :
Now we will use Series.select()
function to select the sales of the listed beverages from the given Series object.
# Function to select the sales of # Coca Cola and Sprite def show_sales(x): if x = = "Sprite" or x = = "Coca Cola" : return True else : return False # Call the function and select the values selected_cities = sr.select(show_sales, axis = 0 ) # Print the returned Series object print (selected_cities) |
Выход :
As we can see in the output, the Series.select()
function has successfully returned the sales data of the desired beverages from the given Series object.
Внимание компьютерщик! Укрепите свои основы с помощью базового курса программирования Python и изучите основы.
Для начала подготовьтесь к собеседованию. Расширьте свои концепции структур данных с помощью курса Python DS. А чтобы начать свое путешествие по машинному обучению, присоединяйтесь к курсу Машинное обучение - базовый уровень.