

However if rest of the columns within matches are unique, then the question shifts to 'which row to preserve'. To remove duplicate rows from a Pandas DataFrame, use the dropduplicates() method. We may want to preserve one copy of the duplicated data. Removing all the duplicates may be extreme.
Pandas remove duplicate rows how to#
Hopefully this article has been beneficial for you to understand how to use the pandas drop_duplicates() function to remove duplicate rows in your data in Python. All the duplicated data is removed due to the 'keepFalse' directive. Pandas dropduplicates() returns only the dataframes unique values, optionally only considering certain columns. We can find all of the duplicates based on the “Name” column by passing ‘subset=’ to the drop_duplicates() function. Let’s say we have the same DataFrame as above. We can remove duplicate rows based on just one column or multiple columns using the “subset” parameter. I have a Pandas dataframe that have duplicate names but with different values, and I want to remove the duplicate names but keep the rows. print(df.drop_duplicates(keep=False, ignore_index=True))ģ Larry 200 Drop Duplicate Rows based on Column Using Pandasīy default, the drop_duplicates() function removes duplicates based on all columns of a DataFrame. Additionally, you can remove duplicates ‘inplace’ like many other pandas functions. The pandas drop_duplicates() function returns a DataFrame, and if you want to reset the index, you can do this with the ‘ignore_index’ option. df. With the argument inplace True, duplicate rows are removed from the original DataFrame. We can drop all duplicates except the last occurrence, or drop all duplicates by passing ‘keep=”last”‘ or ‘keep=False’ respectively. By default, a new DataFrame with duplicate rows removed is returned. The default setting for drop_duplicates() is to drop all duplicates except the first. Parameters subsetcolumn label or sequence of labels, optional Only consider certain columns for identifying duplicates, by default use all of the columns.
Pandas remove duplicate rows series#
If we want to remove these duplicate rows, we can use the pandas drop_duplicates() function like in the following Python code: print(df.drop_duplicates()) DataFrame.duplicated(subsetNone, keep'first') source Return boolean Series denoting duplicate rows. We see above that we have 2 duplicate rows. By default, it marks all duplicates as True except the first occurrence. The duplicated() function returns a Series with boolean values denoting where we have duplicate rows. We can do this easily using the pandas duplicated() function. Let’s find the duplicate rows in this DataFrame. Let’s say we have the following DataFrame: df = pd.DataFrame() With Python, we can find and remove duplicate rows in data very easily using the pandas package and the pandas drop_duplicates() function.

Finding and removing duplicate records in our data is one such situation where we may have to fix our data. When working with data, it’s important to be able to find any problems with our data. Steps to Remove Duplicates from Pandas DataFrame Step 1: Gather the data that contains the duplicatesįirstly, you’ll need to gather the data that contains the duplicates.įor example, let’s say that you have the following data about boxes, where each box may have a different color or shape: ColorĪs you can see, there are duplicates under both columns.īefore you remove those duplicates, you’ll need to create Pandas DataFrame to capture that data in Python.To drop duplicate rows in a DataFrame or Series in pandas, the easiest way is to use the pandas drop_duplicates() function. df.sortvalues('var2', ascendingFalse).dropduplicates('var1').sortindex() Method 2: Remove Duplicates in Multiple Columns and Keep.

In the next section, you’ll see the steps to apply this syntax in practice. You can use the following methods to remove duplicates in a pandas DataFrame but keep the row that contains the max value in a particular column: Method 1: Remove Duplicates in One Column and Keep Row with Max. Pandas dropduplicates() Function Syntax subset: Subset takes a column or list of column label for identifying duplicate rows. If so, you can apply the following syntax to remove duplicates from your DataFrame: df.drop_duplicates() Need to remove duplicates from Pandas DataFrame?
