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To know the number of rows or the number of columns in a DataFrame, we use the len() function:

         >>> nRows = len(groceryDF.index)
         >>> nCols = len(groceryDF.columns)
         >>> print("Number of rows:", nRows)
              Number of rows: 8
         >>> print("Number of columns:", nCols)
              Number of columns: 4


               index attribute yields row labels.
               columns attribute yields column attributes.
               len() function yields the number of rows/columns.


        Alternatively, we can use the size attribute of the DataFrame to retrieve the number of rows or the number of
        columns in a DataFrame, as shown below:
         >>> nRows = groceryDF.index.size
         >>> nCols = groceryDF.columns.size
         >>> print("Number of rows:", nRows)
              Number of rows: 8
         >>> print("Number of columns:", nCols)
              Number of columns: 4
        2.5 Summary Information about a DataFrame

        The info() method of a DataFrame provides the following summary information about a DataFrame:
        •  The number of rows, and the row indexes.
        •  The names of columns, the number of non-null entries in each column, and the type objects in each column, as
            shown below:

         >>> groceryDF.info()
              <class 'pandas.core.frame.DataFrame'>
              RangeIndex: 8 entries, 0 to 7
              Data columns (total 4 columns):
               #   Column    Non-Null Count  Dtype
              ---  ------    --------------  -----
               0   Product   8 non-null      object
               1   Category  8 non-null      object
               2   Price     8 non-null      int64
               3   Quantity  8 non-null      int64
              dtypes: int64(2), object(2)
              memory usage: 384.0+ bytes

        Note that the above DataFrame has 8 entries, which is the same as the number of rows. The total of 4 columns is given
        in the "Data columns" section.

               Attribute ndim of Pandas DataFrame: Yields the number of dimensions of a DataFrame.
               Attribute shape of the DataFrame: Returns a tuple of the form (n_rows, n_cols).
               Attributes index: Labels along the rows (row labels).

               Attributes columns: Labels used across columns (column names) of the dataframe.
               info() method of a DataFrame: Returns the number of rows, and the row indexes, the names of columns, the
               number of non-null entries in each column, and the type objects in each column.







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