You can manipulate a DataFrame with methods and operators. The DataFrames created using the DataFrame() constructor, or the DataFrame() and DataFrame.from_table() and DataFrame.from_query() functions have the same methods and operators.
DataFrame Methods
A DataFrame method has the basic syntax DataFrame.method(arguments). Using the specified DataFrame and arguments, the method returns a new DataFrame. The specified DataFrame remains unchanged.
| DataFrame Method | Description |
|---|---|
| assign() Method | Assigns new column expressions in a DataFrame. |
| concat() Method | Concatenate two teradataml DataFrame objects along the index axis. |
| describe() Method | Generates statistics for numeric columns. Computes the count, mean, std, min, percentiles, and max for numeric columns. |
| drop() Method | Drops specified labels from rows or columns in a DataFrame. |
| dropna() Method | Removes rows with null values in a DataFrame. |
| filter() Method | Returns only the filtered columns or rows (based on the index) of a DataFrame. Filter is item, like, or regex. Other filters are operators index[] and loc[]. |
| get() Method | Retrieves required columns from a DataFrame using column names as key. |
| get_values() Method | Retrieves all values (only) present in a DataFrame. |
| groupby() Method | Returns all columns of a DataFrame, grouped as specified. |
| head() Method | Returns the first n rows of a DataFrame. |
| join() Method | Joins two different teradataml DataFrames together. |
| map_row() Method | Applies a function to every row in a teradataml DataFrame and returns a teradataml DataFrame. |
| map_partition() Method | Applies a function to a group or partition of rows in a teradataml DataFrame and returns a teradataml DataFrame. |
| merge() Method | Merges two teradataml DataFrames together. |
| sample() Method | Samples rows from a DataFrame, directly or based on conditions. |
| select() Method | Returns only the selected columns of a DataFrame. |
| set_index() Method | Assigns one or more existing columns as the new index to a DataFrame. |
| show_query() Method | Returns underlying SQL for the teradataml DataFrame. |
| sort() Method | Returns all columns of a DataFrame, sorted as specified. |
| sort_index() Method | Returns sorted objects by labels (along an axis) in either ascending or descending order for a DataFrame. |
| squeeze() Method | Squeezes one-dimensional axis objects into a scalar for DataFrames with a single element, or a Series object for a DataFrame with a single column. |
| tail() Method | Returns the last n rows of the sorted DataFrame. |
For a list of regular aggregate functions supported by DataFrame, see Regular Aggregate Functions Supported by DataFrame.
For a list of time series aggregate functions, see Time Series Aggregate Functions.
Operators
- DataFrame.loc[arguments]
- DataFrame.iloc[arguments]
- DataFrame[arguments]
All operators are filters. Another filter is the filter() method.
| DataFrame Operator | Description |
|---|---|
| index[] Operator | Returns only the filtered rows of a DataFrame.
Filter uses logical expressions composed of DataFrame columns and Python literals. |
| loc[] Operator | Returns new DataFrame that has only the filtered columns and rows of a DataFrame accessed by labels. |
| iloc[] Operator | Returns new DataFrame that has only the filtered columns and rows of a DataFrame accessed by integer values. |