Dataframe get index of last row
WebFeb 4, 2013 · Use DataFrameGroupBy.agg: df = df.index.to_series ().groupby (df ['id']).first ().reset_index (name='x') print (df) id x 0 1 0 1 2 2 2 3 7 3 4 13 If want also last index values: df = df.index.to_series ().groupby (df ['id']).agg ( ['first','last']).reset_index () print (df) id first last 0 1 0 1 1 2 2 6 2 3 7 12 3 4 13 13 Share WebWe can also access it by indexing df.index and at:. df.at[df.index[-1], 'e'] It's faster than iloc but slower than without indexing.. If we decide to assign a value to the last element in column "e", the above method is much faster than the other two options (9-11 times faster):
Dataframe get index of last row
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WebFor a DataFrame with a sorted DatetimeIndex, this function selects the last few rows based on a date offset. Parameters offsetstr, DateOffset, dateutil.relativedelta The offset length of the data that will be selected. For instance, ‘3D’ will display all the rows having their index within the last 3 days. Returns Series or DataFrame WebOct 24, 2016 · This is applicable for any number of rows you want to extract and not just the last row. For example, if you want last n number of rows of a dataframe, where n is any integer less than or equal to the number of columns present in the dataframe, then you can easily do the following: y = df.iloc [:,n:] Replace n by the number of columns you want.
WebTo select the last row of dataframe using iloc [], we can just skip the column section and in row section pass the -1 as row number. Based on negative indexing, it will select the last row of the dataframe, Advertisements Copy to clipboard df.iloc[-1] We got the last row of dataframe as a series object. WebRemove Rows with Infinite Values from pandas DataFrame in Python (Example Code) Set datetime Object to Local Time Zone in Python (Example) Accessing Last Element Index of pandas DataFrame in Python (4 Examples)
WebSep 13, 2024 · 4 Answers Sorted by: 15 Use last_valid_index: s = pd.Series ( [False, False, True, True, False, False]) s.where (s).last_valid_index () Output: 3 Using @user3483203 example s = pd.Series ( ['dog', 'cat', 'fish', 'cat', 'dog', 'horse'], index= [*'abcdef']) s.where (s=='cat').last_valid_index () Output 'd' Share Follow edited Feb 12, 2024 at 18:51 WebJan 30, 2024 · Using the Pandas iloc [-1] attribute you can select the last row of the DataFrame. iloc [] is used to select the single row or column by using an index. iloc [-1] property return the last row of DataFrame in the form of Pandas Series.
WebJun 22, 2024 · A Computer Science portal for geeks. It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions.
WebJul 15, 2024 · Method 1: Using for loop. In Python, we can easily get the index or rows of a pandas DataFrame object using a for loop. In this method, we will create a pandas … increase size of clipboard windows 10WebIn this tutorial, I’ll illustrate how to get access to the last element of a pandas DataFrame in the Python programming language. The tutorial consists of the following contents: 1) … increase size of applocker logsWebGet last row of pandas dataframe as a series. To select the last row of dataframe using iloc [], we can just skip the column section and in row section pass the -1 as row number. … increase size of background image cssWebAug 25, 2024 · Then use the apply function to perform one operation on the entire column as follows. def get_filename (path): temp_str = path.split ('/') return temp_str [-1] df ["filename"] = df ["filename"].apply (get_filename) In addition to the above answers you could also use the string methods: Not sure which is fastest. increase size of c drive without formattingWebAug 3, 2024 · Both methods return the value of 1.2. Another way of getting the first row and preserving the index: x = df.first ('d') # Returns the first day. '3d' gives first three days. According to pandas docs, at is the fastest way to access a scalar value such as the use case in the OP (already suggested by Alex on this page). increase size of bars in excel chartWebMar 26, 2024 · df.iloc[-2] will get you the penultimate row info for all columns. If you want a specific column only, df.loc doesn't like the minus sign, so one way you could do it would be: df.loc[(df.shape[0]-2), 'your_column_name'] Where df.shape[0] gets your row count, and -2 removes 2 from it to give you the index number for your penultimate row. Then ... increase size of carpets in sims 4WebFeb 5, 2024 · df ['Salary'].iloc [-1] df.Salary.iloc [-1] are synonymous. Iloc is the way to retrieve items in a pandas df by their index. df ['Salary'].values [-1] creates a list of the Salary column and returns the last items df ['Salary'].tail (1) df.Salary.tail (1) returns the last row of the salary column. increase size of checkbox