nxcals.api.extraction.data.builders.DataFrame.head

DataFrame.head() → Optional[Row]

DataFrame.head(n: int) → List[Row]

Returns the first n rows.

New in version 1.3.0.

Changed in version 3.4.0: Supports Spark Connect.

Notes

This method should only be used if the resulting array is expected to be small, as all the data is loaded into the driver’s memory.

Parameters:

n (int, optional) – default 1. Number of rows to return.

Returns:

If n is greater than 1, return a list of Row.
If n is 1, return a single Row.

Examples

>>> df = spark.createDataFrame([
...     (2, "Alice"), (5, "Bob")], schema=["age", "name"])
>>> df.head()
Row(age=2, name='Alice')
>>> df.head(1)
[Row(age=2, name='Alice')]