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The method  describe()  which  returns  a  DataFrame  comprising  the  statistics-  count,  mean,  standard
              deviation, minimum, maximum, and quartiles, about each column in the DataFrame that storenumerical data.
              By specifying include='all' as the keyword argument, the summary information includes count, unique,
              top, and frequency statistics for each non-numeric column.
          42.  Which of the method of Pandas DataFame df can be used to perform the following tasks:

              (i)  Display statistical summary about a DataFrame.
              (ii)  Display first n records of a DataFrame.

              (iii)  Display last n records of a DataFrame.
              (iv)  Set a column as an index

              (v)  Distinct elements in a column.
              (vi)  Count of occurrences of each unique value in a column of the dataframe.

              (vii)  Drop a column or row from the DataFrame.
              (viii) Rename one or more columns in a DataFrame

              (ix)  Writing a DataFrame object to a csv file.
              (x)   Organise the data in a DataFrame into groups, based on specific criteria, such as values stored in one or
                  more columns.

         Ans: (i)  df.describe()
              (ii)  df.head()
              (iii)  df.tail()
              (iv)  df.set_index()
              (v)  df.unique()
              (vi)  df.value_counts()

              (vii)  df.drop()
              (viii) df.rename()
              (ix)  df.to_csv()
              (x)  df.groupby()

          43.  What is the default value of axis in Pandas DataFrame methods?
         Ans. Default axis along which the operation is to be performed is set to 'index' or 0 which denotes that the operation
              is to be applied column-wise across rows. Alternatively, we may apply the operation row-wise across columns by
              setting the axis to 'columns' or 1.
          44.  Explain the  Pandas method that allow us to concatenate a DataFrame with the another DataFrame.

         Ans. Pandas method pd.concat() can be used to concatenate a DataFrame with another DataFrame. By default,
              the method concatenates the two dataframes rows wise (axis = 0). However, we can also concatenate the
              DataFrames columnwise by setting keyword argument axis = 1.

          45.  Determine the aggregate methods supported by Pandas Series for performing the following operations:

              (i)  To compute sum of values in a column or across specified axis in a DataFrame.
              (ii)  To compute average value of a column or across specified axis in a DataFrame.
              (iii)  To find the maximum value in a column or across specified axis in a DataFrame.

              (iv)  To find the minimum value in a column or across specified axis in a DataFrame

          338  Touchpad Informatics Practices-XII
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