How do I get the row count of a Pandas DataFrame?

For a DataFrame df, one can use any of the following:

• len(df.index)
• df.shape[0]

count_row = df.shape[0] # Gives number of rows
count_col = df.shape[1] # Gives number of columns

• df[df.columns[0]].count() (slowest, but avoids counting NaN values in the first column)